Added the old repo, refactored it, added the C jit.

27 files changed, 12024 insertions, 0 deletions

diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..de683cd
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use guix -m manifest.scm
\ No newline at end of file
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..1b15d60
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,31 @@
+CC = clang
+
+STATIC_LIB = include/libccdjit.a
+SHARED_LIB = include/libccdjit.so
+
+SRC = src/main.c src/app.c src/render.c src/font.c src/util.c src/buffers.c src/ecex.c src/config.c src/eval.c
+BIN = bin/ecex
+
+PKG_CFLAGS = $(shell pkg-config --cflags glfw3)
+PKG_LIBS   = $(shell pkg-config --libs glfw3)
+
+CFLAGS = -std=c11 -Wall -Wextra -pedantic -Iinclude $(PKG_CFLAGS)
+LDLIBS = $(PKG_LIBS) -lGL -lm
+
+.PHONY: all static shared clean run
+
+all: static
+
+static: $(SRC) $(STATIC_LIB)
+	@mkdir -p bin
+	$(CC) $(CFLAGS) $(SRC) $(STATIC_LIB) -o $(BIN) $(LDLIBS)
+
+shared: $(SRC) $(SHARED_LIB)
+	@mkdir -p bin
+	$(CC) $(CFLAGS) $(SRC) -Linclude -lccdjit -o $(BIN) $(LDLIBS)
+
+run: static
+	LD_LIBRARY_PATH=include ./$(BIN)
+
+clean:
+	rm -f $(BIN)
diff --git a/config/ecexrc.c b/config/ecexrc.c
new file mode 100644
index 0000000..db4b6b9
--- /dev/null
+++ b/config/ecexrc.c
@@ -0,0 +1,142 @@
+#include "ecex.h"
+#include "buffers.h"
+
+#define C(x) ((float)(x) / 255.0f)
+#define RGB(r, g, b) C(r), C(g), C(b)
+
+/* Gruvbox dark palette */
+#define GB_DARK0_HARD  RGB(0x1d, 0x20, 0x21)
+#define GB_DARK0       RGB(0x28, 0x28, 0x28)
+#define GB_DARK1       RGB(0x3c, 0x38, 0x36)
+#define GB_DARK2       RGB(0x50, 0x49, 0x45)
+
+#define GB_LIGHT0      RGB(0xfb, 0xf1, 0xc7)
+#define GB_LIGHT1      RGB(0xeb, 0xdb, 0xb2)
+#define GB_LIGHT2      RGB(0xd5, 0xc4, 0xa1)
+
+#define GB_RED         RGB(0xfb, 0x49, 0x34)
+#define GB_GREEN       RGB(0xb8, 0xbb, 0x26)
+#define GB_YELLOW      RGB(0xfa, 0xbd, 0x2f)
+#define GB_BLUE        RGB(0x83, 0xa5, 0x98)
+#define GB_PURPLE      RGB(0xd3, 0x86, 0x9b)
+#define GB_AQUA        RGB(0x8e, 0xc0, 0x7c)
+#define GB_ORANGE      RGB(0xfe, 0x80, 0x19)
+
+static int hello_command(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    buffer_insert(buf, "Hello from Gruvbox ecex config!\n");
+    return 0;
+}
+
+static int make_notes_command(ecex_t *ed) {
+    buffer_t *notes = ecex_find_buffer(ed, "*notes*");
+
+    if (!notes) {
+        notes = ecex_create_buffer(ed, "*notes*", NULL, 0);
+    }
+
+    if (notes) {
+        buffer_insert(notes, "Created or reused *notes* from command.\n");
+        ecex_switch_buffer(ed, "*notes*");
+    }
+
+    return 0;
+}
+
+
+static int demo_line_action(ecex_t *ed,
+                            buffer_t *buffer,
+                            size_t line,
+                            const char *payload,
+                            void *userdata) {
+    (void)buffer;
+    (void)line;
+    (void)userdata;
+
+    buffer_t *notes = ecex_find_buffer(ed, "*notes*");
+    if (!notes) {
+        notes = ecex_create_buffer(ed, "*notes*", NULL, 0);
+    }
+
+    if (!notes) return -1;
+
+    ecex_switch_buffer(ed, "*notes*");
+    buffer_insert(notes, payload ? payload : "selected an interactive line\n");
+    return 0;
+}
+
+static int demo_interactive_command(ecex_t *ed) {
+    buffer_t *menu = ecex_create_interactive_buffer(ed, "*demo-menu*");
+    if (!menu) return -1;
+
+    buffer_clear(menu);
+    buffer_set_interactive(menu, 1);
+
+    buffer_append(menu, "Demo interactive buffer\n");
+    buffer_append(menu, "Move to a line and press ENTER.\n\n");
+
+    ecex_interactive_append_line(ed,
+                                 menu,
+                                 "Insert hello into *notes*",
+                                 demo_line_action,
+                                 "hello from an interactive config buffer!\n",
+                                 NULL);
+
+    ecex_interactive_append_line(ed,
+                                 menu,
+                                 "Insert gruvbox note into *notes*",
+                                 demo_line_action,
+                                 "gruvbox menu action selected\n",
+                                 NULL);
+
+    ecex_switch_buffer(ed, "*demo-menu*");
+    return 0;
+}
+
+int ecex_config_init(ecex_t *ed) {
+    ecex_set_font_size(ed, 20.0f);
+
+    ecex_set_bg_color(ed, GB_DARK0_HARD);
+    ecex_set_fg_color(ed, GB_LIGHT1);
+
+    ecex_set_status_bg_color(ed, GB_DARK0);
+    ecex_set_status_fg_color(ed, GB_YELLOW);
+    ecex_set_status_border_color(ed, GB_DARK1);
+
+    ecex_set_minibuffer_bg_color(ed, GB_DARK1);
+    ecex_set_minibuffer_fg_color(ed, GB_LIGHT0);
+
+    ecex_set_completion_enabled(ed, 1);
+    ecex_set_completion_fg_color(ed, GB_DARK2);
+
+    ecex_set_interactive_highlight_bg_color(ed, GB_DARK1);
+    ecex_set_interactive_highlight_fg_color(ed, GB_YELLOW);
+
+    ecex_set_cursor_color(ed, GB_AQUA);
+    ecex_set_region_bg_color(ed, GB_DARK2);
+
+    ecex_register_command(ed, "hello", hello_command);
+    ecex_register_command(ed, "make-notes", make_notes_command);
+    ecex_register_command(ed, "demo-interactive", demo_interactive_command);
+
+    ecex_bind_key(ed, "C-h", "hello");
+    ecex_bind_key(ed, "C-m", "make-notes");
+    ecex_bind_key(ed, "F2", "list-commands");
+    ecex_bind_key(ed, "F3", "list-buffers");
+    ecex_bind_key(ed, "F4", "demo-interactive");
+    ecex_bind_key(ed, "C-q", "quit");
+    ecex_bind_key(ed, "C-x h", "beginning-of-buffer");
+
+    ecex_bind_key(ed, "C-x b n", "next-buffer");
+    ecex_bind_key(ed, "C-x b p", "previous-buffer");
+
+    buffer_t *scratch = ecex_current_buffer(ed);
+
+    buffer_insert(scratch, "ecex config loaded with Gruvbox colors!\n");
+    buffer_insert(scratch, "Try F1 M-x, C-x C-f, C-x C-s, F2 commands, F3 buffers, F4 demo menu, C-x b n/p.\n");
+    buffer_insert(scratch, "Eval live C snippets with C-x C-e (line), C-x e r (marked region), C-x e b (buffer), C-x e f (file).\n");
+    buffer_insert(scratch, "Example line to edit then C-x C-e: ecex_set_font_size(ed, 28.0f);\n");
+    buffer_insert(scratch, "Example relative change: ecex_adjust_font_size(ed, 2.0f);\n\n");
+
+    return 0;
+}
diff --git a/include/app.h b/include/app.h
new file mode 100644
index 0000000..cb09b04
--- /dev/null
+++ b/include/app.h
@@ -0,0 +1,95 @@
+#ifndef ECEX_APP_H
+#define ECEX_APP_H
+
+#include "ecex.h"
+#include "font.h"
+
+#include <GLFW/glfw3.h>
+#include <stddef.h>
+
+#define ECEX_MINIBUFFER_SIZE 256
+#define ECEX_PREFIX_SIZE 128
+
+typedef enum app_mode {
+    APP_MODE_EDIT = 0,
+    APP_MODE_MX = 1,
+    APP_MODE_PREFIX = 2,
+    APP_MODE_PROMPT = 3,
+    APP_MODE_ISEARCH = 4,
+} app_mode_t;
+
+typedef struct app {
+    ecex_t *ed;
+    GLFWwindow *window;
+
+    int width;
+    int height;
+    int dirty;
+
+    app_mode_t mode;
+
+    char minibuffer[ECEX_MINIBUFFER_SIZE];
+    size_t minibuffer_len;
+
+    char message[ECEX_MINIBUFFER_SIZE];
+
+    ecex_prompt_request_t prompt_kind;
+    int isearch_backward;
+    char isearch_query[ECEX_MINIBUFFER_SIZE];
+    size_t isearch_len;
+    size_t isearch_origin;
+    size_t isearch_match;
+    int isearch_has_match;
+    char last_search_query[ECEX_MINIBUFFER_SIZE];
+    char prompt_label[128];
+    char prompt_input[1024];
+    size_t prompt_input_len;
+
+    /*
+     * File/path prompt completion state for find-file and write-file.
+     * prompt_completion_query stores the original typed path/query while
+     * prompt_input is temporarily replaced with the selected candidate.
+     */
+    int prompt_completion_active;
+    char prompt_completion_query[1024];
+    size_t prompt_completion_index;
+    size_t prompt_completion_count;
+    char prompt_completion_preview[8][1024];
+    size_t prompt_completion_preview_start;
+    size_t prompt_completion_preview_count;
+
+    /*
+     * M-x completion state.
+     * completion_query is the original user query used to build the candidate
+     * list. This lets the UI replace the minibuffer with a candidate while
+     * Up/Down still cycle through matches for the original query, e.g.
+     * "-buffer" -> next-buffer / previous-buffer / end-of-buffer / ...
+     */
+    int completion_active;
+    char completion_query[ECEX_MINIBUFFER_SIZE];
+    size_t completion_index;
+    size_t completion_count;
+
+    char prefix[ECEX_PREFIX_SIZE];
+    size_t prefix_len;
+
+    int current_mods;
+
+    /*
+     * GLFW sends key events and text events separately. When a printable
+     * key is consumed as part of a command sequence, suppress the matching
+     * char_callback so it does not insert into the buffer after the command
+     * returns to edit mode.
+     */
+    int suppress_next_char;
+
+    font_t font;
+    char font_path[4096];
+} app_t;
+
+void app_init(app_t *app, ecex_t *ed);
+void app_set_window(app_t *app, GLFWwindow *window);
+void app_install_callbacks(app_t *app);
+void app_message(app_t *app, const char *msg);
+
+#endif
diff --git a/include/buffers.h b/include/buffers.h
new file mode 100644
index 0000000..503dfb8
--- /dev/null
+++ b/include/buffers.h
@@ -0,0 +1,78 @@
+#ifndef ECEX_BUFFERS_H
+#define ECEX_BUFFERS_H
+
+#include "types.h"
+
+#include <stddef.h>
+
+buffer_t *buffer_new(const char *name, const char *path, int read_only);
+void buffer_free(buffer_t *buffer);
+
+int buffer_reserve(buffer_t *buffer, size_t needed);
+int buffer_clear(buffer_t *buffer);
+int buffer_set_text(buffer_t *buffer, const char *text);
+
+int buffer_insert_at(buffer_t *buffer, size_t pos, const char *text);
+int buffer_insert(buffer_t *buffer, const char *text);
+int buffer_append(buffer_t *buffer, const char *text);
+int buffer_prepend(buffer_t *buffer, const char *text);
+
+int buffer_insert_char_at(buffer_t *buffer, size_t pos, char c);
+int buffer_insert_char(buffer_t *buffer, char c);
+
+int buffer_delete_range(buffer_t *buffer, size_t start, size_t end);
+int buffer_delete_selection(buffer_t *buffer);
+int buffer_replace_selection(buffer_t *buffer, const char *text);
+int buffer_backspace(buffer_t *buffer);
+int buffer_delete_forward(buffer_t *buffer);
+int buffer_kill_line(buffer_t *buffer);
+int buffer_undo(buffer_t *buffer);
+int buffer_redo(buffer_t *buffer);
+void buffer_clear_undo(buffer_t *buffer);
+
+void buffer_set_point(buffer_t *buffer, size_t point);
+void buffer_move_left(buffer_t *buffer);
+void buffer_move_right(buffer_t *buffer);
+void buffer_move_up(buffer_t *buffer);
+void buffer_move_down(buffer_t *buffer);
+void buffer_move_word_left(buffer_t *buffer);
+void buffer_move_word_right(buffer_t *buffer);
+void buffer_move_beginning_of_line(buffer_t *buffer);
+void buffer_move_end_of_line(buffer_t *buffer);
+void buffer_move_beginning_of_buffer(buffer_t *buffer);
+void buffer_move_end_of_buffer(buffer_t *buffer);
+int buffer_search_forward(buffer_t *buffer, const char *query, size_t start, size_t *out_pos);
+int buffer_search_backward(buffer_t *buffer, const char *query, size_t start, size_t *out_pos);
+
+void buffer_set_mark(buffer_t *buffer, size_t mark);
+void buffer_clear_mark(buffer_t *buffer);
+int buffer_has_selection(buffer_t *buffer);
+void buffer_selection_range(buffer_t *buffer, size_t *out_start, size_t *out_end);
+
+size_t buffer_line_start_at(buffer_t *buffer, size_t pos);
+size_t buffer_line_end_at(buffer_t *buffer, size_t pos);
+size_t buffer_current_line_start(buffer_t *buffer);
+size_t buffer_current_line_end(buffer_t *buffer);
+size_t buffer_current_column(buffer_t *buffer);
+size_t buffer_current_line_number(buffer_t *buffer);
+size_t buffer_line_count(buffer_t *buffer);
+
+char *buffer_substring(buffer_t *buffer, size_t start, size_t end);
+char *buffer_current_line_copy(buffer_t *buffer);
+
+int buffer_load_file(buffer_t *buffer, const char *path);
+int buffer_save(buffer_t *buffer);
+int buffer_save_as(buffer_t *buffer, const char *path);
+
+void buffer_set_interactive(buffer_t *buffer, int interactive);
+int buffer_is_interactive(buffer_t *buffer);
+int buffer_clear_interactive_actions(buffer_t *buffer);
+int buffer_add_interactive_action(buffer_t *buffer,
+                                  size_t line,
+                                  ecex_interactive_line_fn fn,
+                                  const char *payload,
+                                  void *userdata);
+ecex_interactive_line_action_t *buffer_interactive_action_at_line(buffer_t *buffer,
+                                                                  size_t line);
+
+#endif
diff --git a/include/ccdjit.h b/include/ccdjit.h
new file mode 100644
index 0000000..f8a212b
--- /dev/null
+++ b/include/ccdjit.h
@@ -0,0 +1,330 @@
+#ifndef CCDJIT_PUBLIC_H
+#define CCDJIT_PUBLIC_H
+
+/*
+ * CCDJIT public embedding API
+ *
+ * This header is the stable boundary for hosts that want to compile and run C
+ * code at runtime.  The implementation lives in ccdjit.c, but the intended use
+ * should be clear from this file alone.
+ *
+ * Basic use:
+ *
+ *      ccdjit_context *ctx = ccdjit_context_new(NULL);
+ *      ccdjit_module *module = NULL;
+ *
+ *      if (ccdjit_compile_string(ctx, source, "plugin.c", &module) == 0) {
+ *              int result = 0;
+ *              ccdjit_module_call_main(module, 0, NULL, &result);
+ *              ccdjit_module_free(module);
+ *      }
+ *      ccdjit_context_free(ctx);
+ *
+ * Return convention:
+ *      Functions returning int use 0 for success and -1 for failure unless
+ *      documented otherwise.  On failure, call ccdjit_context_last_error().
+ *
+ * Lifetime:
+ *      A context owns options, include paths, registered symbols, and the last
+ *      diagnostic.  A module owns generated code or a loaded CCDJIT binary.
+ *      Modules keep their context state alive, so ccdjit_context_free() may be
+ *      called before ccdjit_module_free(); the context is released when the
+ *      last module using it is freed.
+ *      Function pointers returned by ccdjit_module_symbol() are invalid after
+ *      ccdjit_module_free().
+ *
+ * Threads:
+ *      Independent contexts may compile and run from different threads.  Do
+ *      not mutate or use the same context or module concurrently from multiple
+ *      threads unless the host provides its own synchronization.
+ *
+ * Safety:
+ *      Normal calls run in the host process.  Set sandbox_execution to
+ *      CCDJIT_SANDBOX_PROCESS to run ccdjit_module_call_main() in a child
+ *      process with optional resource, syscall, and filesystem limits.
+ */
+
+#include <stddef.h>
+#include <stdio.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct ccdjit_context ccdjit_context;
+typedef struct ccdjit_module ccdjit_module;
+
+typedef struct {
+	/* Host compiler or linker driver.  NULL uses $CC, then cc. */
+	const char *driver;
+
+	/* Extra linker arguments such as -L, -l, or -Wl options. */
+	const char *const *link_args;
+	size_t link_arg_count;
+
+	/* Print the host linker command to stderr when nonzero. */
+	int verbose;
+} ccdjit_link_options;
+
+/*
+ * Host symbol callback.  Return NULL when the name is unknown.
+ *
+ * The returned pointer is used as an external function or object address by
+ * generated code.  Keep any pointed-to object alive while modules using it may
+ * run.
+ */
+typedef void *(*ccdjit_symbol_resolver)(const char *name, void *userdata);
+
+typedef enum {
+	/* Run generated code directly in the host process. */
+	CCDJIT_SANDBOX_OFF = 0,
+
+	/* Run ccdjit_module_call_main() in a forked child process. */
+	CCDJIT_SANDBOX_PROCESS = 1,
+} ccdjit_sandbox_mode;
+
+typedef enum {
+	/*
+	 * Minimal child profile: enough to write the result pipe, write
+	 * captured output, and exit.  Unexpected syscalls are trapped.
+	 */
+	CCDJIT_SANDBOX_SYSCALL_STRICT = 0,
+
+	/* STRICT plus read/close for simple stdio-style code. */
+	CCDJIT_SANDBOX_SYSCALL_STDIO = 1,
+
+	/* STDIO plus mmap/munmap/mprotect/brk/clock_gettime. */
+	CCDJIT_SANDBOX_SYSCALL_RUNTIME = 2,
+
+	/* Disable the seccomp filter.  Resource limits still apply. */
+	CCDJIT_SANDBOX_SYSCALL_PERMISSIVE = 3,
+} ccdjit_sandbox_syscall_policy;
+
+typedef enum {
+	/* Runtime file syscalls are denied by the syscall policy. */
+	CCDJIT_SANDBOX_FS_NONE = 0,
+
+	/* Permit read-only access under explicitly added roots. */
+	CCDJIT_SANDBOX_FS_READ_ONLY_ROOTS = 1,
+
+	/* Permit writes only for roots added with writable != 0. */
+	CCDJIT_SANDBOX_FS_WRITABLE_ROOTS = 2,
+} ccdjit_sandbox_filesystem_policy;
+
+typedef struct {
+	/* Allow #include to read files from include paths. */
+	int allow_filesystem_includes;
+
+	/* Allow the preprocessor to discover and read host system includes. */
+	int allow_system_includes;
+
+	/* Allow executable mappings for JIT code and loaded CCDJIT binaries. */
+	int allow_executable_memory;
+
+	/* ccdjit_sandbox_mode.  Default is CCDJIT_SANDBOX_OFF. */
+	int sandbox_execution;
+
+	/* ccdjit_sandbox_syscall_policy.  Default is STRICT. */
+	int sandbox_syscalls;
+
+	/* ccdjit_sandbox_filesystem_policy.  Default is FS_NONE. */
+	int sandbox_filesystem;
+
+	/*
+	 * In sandbox mode, default dlsym lookup is disabled unless this is set.
+	 * Prefer explicit ccdjit_context_register_symbol() capabilities.
+	 */
+	int sandbox_allow_implicit_symbols;
+
+	/* Wall-clock timeout for one sandboxed main call.  Zero means no limit.
+	 */
+	unsigned int sandbox_timeout_ms;
+
+	/* RLIMIT_CPU for sandboxed calls, rounded up to seconds by the OS. */
+	unsigned int sandbox_cpu_time_ms;
+
+	/* RLIMIT_AS for sandboxed calls.  Zero means keep the host default. */
+	size_t sandbox_address_space_bytes;
+
+	/* RLIMIT_STACK for sandboxed calls.  Zero means keep the host default.
+	 */
+	size_t sandbox_stack_bytes;
+
+	/* RLIMIT_FSIZE for sandboxed calls.  Zero means keep the host default.
+	 */
+	size_t sandbox_file_size_bytes;
+
+	/* Captured stdout/stderr cap for sandboxed calls.  Zero means 64 KiB.
+	 */
+	size_t sandbox_output_limit_bytes;
+
+	/*
+	 * Preprocessor output byte cap.  Zero uses the default currently 128
+	 * MiB.
+	 */
+	size_t preprocessor_output_limit_bytes;
+
+	/* Macro expansion recursion cap.  Zero uses the default. */
+	unsigned int preprocessor_macro_depth_limit;
+
+	/* Nested include cap.  Zero uses the default. */
+	unsigned int preprocessor_include_depth_limit;
+} ccdjit_options;
+
+typedef struct {
+	/* Compiler phase such as LEXER, PARSER, JIT, API, or SANDBOX. */
+	const char *phase;
+
+	/* Source file, binary path, symbol name, or "<input>". */
+	const char *filename;
+
+	/* Human-readable error text owned by the context. */
+	const char *message;
+
+	/* Optional source excerpt for lexer/parser/type diagnostics. */
+	const char *source_line;
+	const char *caret_line;
+
+	/* One-based line and column when available, otherwise zero. */
+	int line;
+	int column;
+
+	/* Raw child wait status or errno-style value for sandbox/API failures.
+	 */
+	int status;
+
+	/* Signal that terminated the sandbox child, or zero. */
+	int signal_number;
+} ccdjit_diagnostic;
+
+/* Create a compiler context.  Passing NULL uses permissive CLI-like defaults.
+ */
+ccdjit_context *ccdjit_context_new(const ccdjit_options *options);
+
+/* Free the context and all context-owned diagnostics/options/lists. */
+void ccdjit_context_free(ccdjit_context *ctx);
+
+/* Add a preprocessor include search path, like -I. */
+int ccdjit_context_add_include_path(ccdjit_context *ctx, const char *path);
+
+/* Restrict filesystem includes to this root when include roots are used. */
+int ccdjit_context_add_include_root(ccdjit_context *ctx, const char *path);
+
+/* Add a preprocessor definition, like -DNAME or -DNAME=value. */
+int ccdjit_context_add_define(ccdjit_context *ctx, const char *define);
+
+/* Grant generated code an explicit external symbol capability. */
+int ccdjit_context_register_symbol(ccdjit_context *ctx, const char *name,
+    void *addr);
+
+/* Add an explicit shared library path for external symbol lookup. */
+int ccdjit_context_add_library(ccdjit_context *ctx, const char *path);
+
+/* Install a fallback external symbol resolver. */
+void ccdjit_context_set_symbol_resolver(ccdjit_context *ctx,
+    ccdjit_symbol_resolver resolver, void *userdata);
+
+/* Update sandbox mode, syscall policy, filesystem policy, and symbol policy. */
+int ccdjit_context_set_sandbox_options(ccdjit_context *ctx, int mode,
+    int syscall_policy, int filesystem_policy, int allow_implicit_symbols);
+
+/* Update all sandbox resource limits in one call. */
+int ccdjit_context_set_sandbox_limits(ccdjit_context *ctx,
+    unsigned int timeout_ms, unsigned int cpu_time_ms,
+    size_t address_space_bytes, size_t stack_bytes, size_t file_size_bytes,
+    size_t output_limit_bytes);
+
+/* Update preprocessor resource limits.  Passing zero keeps the default. */
+int ccdjit_context_set_preprocessor_limits(ccdjit_context *ctx,
+    size_t output_limit_bytes, unsigned int macro_depth,
+    unsigned int include_depth);
+
+/*
+ * Add a Landlock filesystem root for sandboxed execution.
+ *
+ * writable is only honored when sandbox_filesystem is
+ * CCDJIT_SANDBOX_FS_WRITABLE_ROOTS.  On systems without Landlock, requesting a
+ * root-based filesystem policy fails while entering the sandbox.
+ */
+int ccdjit_context_add_sandbox_filesystem_root(ccdjit_context *ctx,
+    const char *path, int writable);
+
+/* Return the last error for this context.  The pointer is context-owned. */
+const ccdjit_diagnostic *ccdjit_context_last_error(ccdjit_context *ctx);
+
+/* Return captured sandbox stdout/stderr from the last sandboxed main call. */
+const char *ccdjit_context_last_stdout(ccdjit_context *ctx);
+const char *ccdjit_context_last_stderr(ccdjit_context *ctx);
+
+/* Compile a source file into a live JIT module. */
+int ccdjit_compile_file(ccdjit_context *ctx, const char *path,
+    ccdjit_module **out);
+
+/* Compile a source string into a live JIT module. */
+int ccdjit_compile_string(ccdjit_context *ctx, const char *source,
+    const char *filename, ccdjit_module **out);
+
+/*
+ * Compile a source file into a live JIT module without requiring main().
+ * Use ccdjit_module_symbol() to find and call exported config/plugin symbols.
+ */
+int ccdjit_compile_file_module(ccdjit_context *ctx, const char *path,
+    ccdjit_module **out);
+
+/*
+ * Compile a source string into a live JIT module without requiring main().
+ * Use ccdjit_module_symbol() to find and call exported config/plugin symbols.
+ */
+int ccdjit_compile_string_module(ccdjit_context *ctx, const char *source,
+    const char *filename, ccdjit_module **out);
+
+/* Convenience wrapper: compile a source string, call main, free the module. */
+int ccdjit_eval_string(ccdjit_context *ctx, const char *source,
+    const char *filename, int argc, char **argv, int *result_out);
+
+/*
+ * Find a function or object symbol in a module.
+ *
+ * Calling the returned function pointer runs in the host process even when the
+ * context has sandbox_execution enabled.  Use ccdjit_module_call_main() for
+ * sandboxed execution.
+ */
+void *ccdjit_module_symbol(ccdjit_module *module, const char *name);
+
+/* Call module main(argc, argv).  Honors CCDJIT_SANDBOX_PROCESS. */
+int ccdjit_module_call_main(ccdjit_module *module, int argc, char **argv,
+    int *result_out);
+
+/* Emit textual assembly-like bytes for inspection. */
+int ccdjit_module_emit_assembly(ccdjit_module *module, FILE *out);
+
+/* Emit a CCDJITB2 binary image. */
+int ccdjit_module_emit_binary(ccdjit_module *module, FILE *out);
+
+/* Emit an ELF64 relocatable object. */
+int ccdjit_module_emit_object(ccdjit_module *module, FILE *out);
+
+/*
+ * Emit a linked host executable.
+ *
+ * This depends on the host compiler driver.  It is intended for trusted build
+ * paths, not sandboxed execution.
+ */
+int ccdjit_module_emit_executable_file(ccdjit_module *module, const char *path,
+    const ccdjit_link_options *options);
+
+/* Emit a CCDJITB2 binary image directly to a path. */
+int ccdjit_module_emit_binary_file(ccdjit_module *module, const char *path);
+
+/* Load a CCDJITB2 binary image into executable memory. */
+int ccdjit_module_load_binary(ccdjit_context *ctx, const char *path,
+    ccdjit_module **out);
+
+/* Free generated code, loaded binary storage, AST, and module-owned source. */
+void ccdjit_module_free(ccdjit_module *module);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/include/common.h b/include/common.h
new file mode 100644
index 0000000..6fd9820
--- /dev/null
+++ b/include/common.h
@@ -0,0 +1,55 @@
+#ifndef ECEX_COMMON_H
+#define ECEX_COMMON_H
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ECEX_OK 0
+#define ECEX_ERR (-1)
+
+#define ECEX_ARRAY_LEN(a) (sizeof(a) / sizeof((a)[0]))
+#define ECEX_MIN(a, b) ((a) < (b) ? (a) : (b))
+#define ECEX_MAX(a, b) ((a) > (b) ? (a) : (b))
+#define ECEX_CLAMP(v, lo, hi) (ECEX_MAX((lo), ECEX_MIN((v), (hi))))
+
+#define ECEX_RETURN_ERR_IF_NULL(p) \
+    do { \
+        if (!(p)) return ECEX_ERR; \
+    } while (0)
+
+#define ECEX_RETURN_NULL_IF_NULL(p) \
+    do { \
+        if (!(p)) return NULL; \
+    } while (0)
+
+#define ECEX_FREE_AND_NULL(p) \
+    do { \
+        free(p); \
+        (p) = NULL; \
+    } while (0)
+
+#define ECEX_GROW_ARRAY(ptr, count, cap, initial_cap) \
+    ecex_grow_array((void **)&(ptr), sizeof(*(ptr)), (count), &(cap), (initial_cap))
+
+static inline int ecex_grow_array(void **ptr,
+                                  size_t item_size,
+                                  size_t count,
+                                  size_t *cap,
+                                  size_t initial_cap) {
+    if (count < *cap) return ECEX_OK;
+
+    size_t new_cap = *cap ? *cap * 2 : initial_cap;
+    while (new_cap <= count) {
+        new_cap *= 2;
+    }
+
+    void *new_ptr = realloc(*ptr, new_cap * item_size);
+    if (!new_ptr) return ECEX_ERR;
+
+    *ptr = new_ptr;
+    *cap = new_cap;
+    return ECEX_OK;
+}
+
+#endif
diff --git a/include/config.h b/include/config.h
new file mode 100644
index 0000000..e7445d8
--- /dev/null
+++ b/include/config.h
@@ -0,0 +1,14 @@
+#ifndef ECEX_CONFIG_H
+#define ECEX_CONFIG_H
+
+#include "ecex.h"
+#include "ccdjit.h"
+#include <stdio.h>
+
+int ecex_load_c_config(ecex_t *ed, const char *path);
+
+void ecex_print_ccdjit_error(ccdjit_context *ctx);
+int ecex_add_ccdjit_include_paths(ccdjit_context *ctx);
+int ecex_register_host_symbols(ccdjit_context *ctx);
+
+#endif
diff --git a/include/ecex.h b/include/ecex.h
new file mode 100644
index 0000000..cefee9b
--- /dev/null
+++ b/include/ecex.h
@@ -0,0 +1,124 @@
+#ifndef ECEX_H
+#define ECEX_H
+
+#include "types.h"
+#include "buffers.h"
+#include "eval.h"
+
+ecex_t *ecex_new(void);
+void ecex_free(ecex_t *ed);
+
+int ecex_reserve_buffers(ecex_t *ed, size_t needed);
+int ecex_add_buffer(ecex_t *ed, buffer_t *buffer);
+
+buffer_t *ecex_create_buffer(ecex_t *ed,
+                             const char *name,
+                             const char *path,
+                             int read_only);
+
+buffer_t *ecex_find_buffer(ecex_t *ed, const char *name);
+int ecex_switch_buffer(ecex_t *ed, const char *name);
+
+buffer_t *ecex_current_buffer(ecex_t *ed);
+ecex_window_t *ecex_current_window(ecex_t *ed);
+size_t ecex_window_count(ecex_t *ed);
+int ecex_sync_current_buffer(ecex_t *ed);
+
+int ecex_split_window_vertically(ecex_t *ed);
+int ecex_split_window_horizontally(ecex_t *ed);
+int ecex_other_window(ecex_t *ed);
+int ecex_previous_window(ecex_t *ed);
+int ecex_delete_window(ecex_t *ed);
+int ecex_delete_other_windows(ecex_t *ed);
+int ecex_balance_windows(ecex_t *ed);
+
+int ecex_next_buffer(ecex_t *ed);
+int ecex_previous_buffer(ecex_t *ed);
+int ecex_kill_buffer(ecex_t *ed, const char *name);
+
+int ecex_keep_jit_module(ecex_t *ed, void *module);
+
+int ecex_set_config_path(ecex_t *ed, const char *path);
+const char *ecex_config_path(ecex_t *ed);
+int ecex_reload_config(ecex_t *ed);
+
+int ecex_register_command(ecex_t *ed, const char *name, ecex_command_fn fn);
+int ecex_execute_command(ecex_t *ed, const char *name);
+void ecex_set_clipboard_callbacks(ecex_t *ed,
+                                  ecex_clipboard_get_fn get_fn,
+                                  ecex_clipboard_set_fn set_fn,
+                                  void *userdata);
+const char *ecex_clipboard_get(ecex_t *ed);
+int ecex_clipboard_set(ecex_t *ed, const char *text);
+
+int ecex_bind_key(ecex_t *ed, const char *key, const char *command);
+const char *ecex_lookup_key(ecex_t *ed, const char *key);
+
+int ecex_define_major_mode(ecex_t *ed, const char *name);
+int ecex_major_mode_by_name(ecex_t *ed, const char *name);
+const char *ecex_major_mode_name(ecex_t *ed, int mode);
+int ecex_buffer_set_major_mode(buffer_t *buffer, int mode);
+int ecex_buffer_set_major_mode_by_name(ecex_t *ed, buffer_t *buffer, const char *name);
+const char *ecex_buffer_major_mode_name(ecex_t *ed, buffer_t *buffer);
+int ecex_bind_mode_key(ecex_t *ed, const char *mode_name, const char *key, const char *command);
+const char *ecex_lookup_key_for_buffer(ecex_t *ed, buffer_t *buffer, const char *key);
+int ecex_key_sequence_has_prefix_for_buffer(ecex_t *ed, buffer_t *buffer, const char *prefix);
+int ecex_auto_set_major_mode(ecex_t *ed, buffer_t *buffer);
+
+int ecex_list_commands(ecex_t *ed);
+int ecex_list_buffers(ecex_t *ed);
+
+buffer_t *ecex_create_interactive_buffer(ecex_t *ed, const char *name);
+int ecex_interactive_append_line(ecex_t *ed,
+                                 buffer_t *buffer,
+                                 const char *text,
+                                 ecex_interactive_line_fn fn,
+                                 const char *payload,
+                                 void *userdata);
+int ecex_interactive_activate_current_line(ecex_t *ed);
+
+int ecex_find_file(ecex_t *ed, const char *path);
+int ecex_save_current_buffer(ecex_t *ed);
+int ecex_write_current_buffer(ecex_t *ed, const char *path);
+int ecex_compile(ecex_t *ed, const char *command);
+int ecex_grep(ecex_t *ed, const char *command);
+int ecex_rerun_compile(ecex_t *ed);
+int ecex_rerun_grep(ecex_t *ed);
+int ecex_next_interactive_action(ecex_t *ed);
+int ecex_previous_interactive_action(ecex_t *ed);
+int ecex_comment_region(ecex_t *ed);
+int ecex_uncomment_region(ecex_t *ed);
+void ecex_request_prompt(ecex_t *ed, ecex_prompt_request_t request, const char *message);
+void ecex_clear_prompt_request(ecex_t *ed);
+
+const char *ecex_complete_command(ecex_t *ed, const char *query);
+
+int ecex_set_font(ecex_t *ed, const char *path);
+float ecex_get_font_size(ecex_t *ed);
+int ecex_set_font_size(ecex_t *ed, float size);
+int ecex_adjust_font_size(ecex_t *ed, float delta);
+
+void ecex_set_bg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_fg_color(ecex_t *ed, float r, float g, float b);
+
+void ecex_set_status_bg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_status_fg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_status_border_color(ecex_t *ed, float r, float g, float b);
+
+void ecex_set_cursor_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_region_bg_color(ecex_t *ed, float r, float g, float b);
+
+void ecex_set_minibuffer_bg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_minibuffer_fg_color(ecex_t *ed, float r, float g, float b);
+
+void ecex_set_completion_fg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_completion_enabled(ecex_t *ed, int enabled);
+
+void ecex_set_interactive_highlight_bg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_interactive_highlight_fg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_current_line_bg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_search_bg_color(ecex_t *ed, float r, float g, float b);
+void ecex_set_line_numbers_enabled(ecex_t *ed, int enabled);
+void ecex_set_current_line_enabled(ecex_t *ed, int enabled);
+
+#endif
diff --git a/include/eval.h b/include/eval.h
new file mode 100644
index 0000000..ca722c2
--- /dev/null
+++ b/include/eval.h
@@ -0,0 +1,17 @@
+#ifndef ECEX_EVAL_H
+#define ECEX_EVAL_H
+
+#include "types.h"
+
+int ecex_eval_source(ecex_t *ed,
+                     const char *source,
+                     const char *filename,
+                     int wrap_as_statements);
+
+int ecex_eval_current_buffer(ecex_t *ed);
+int ecex_eval_current_line(ecex_t *ed);
+int ecex_eval_current_region(ecex_t *ed);
+int ecex_eval_file(ecex_t *ed, const char *path);
+int ecex_eval_rerun_last(ecex_t *ed);
+
+#endif
diff --git a/include/font.h b/include/font.h
new file mode 100644
index 0000000..a1c3d54
--- /dev/null
+++ b/include/font.h
@@ -0,0 +1,36 @@
+#ifndef ECEX_FONT_H
+#define ECEX_FONT_H
+
+#include <GLFW/glfw3.h>
+#include "stb_truetype.h"
+
+#define ECEX_FONT_BITMAP_W 512
+#define ECEX_FONT_BITMAP_H 512
+#define ECEX_FONT_FIRST_CHAR 32
+#define ECEX_FONT_CHAR_COUNT 96
+
+typedef struct font {
+    GLuint texture;
+    stbtt_bakedchar chars[ECEX_FONT_CHAR_COUNT];
+
+    float size_px;
+
+    /*
+     * draw_text() takes y as a baseline. These metrics let render.c place
+     * baselines, highlights, bars, and cursors from the same font-scaled
+     * coordinate system instead of fixed pixel constants.
+     */
+    float ascent_px;
+    float descent_px;
+    float line_gap_px;
+    float line_height;
+} font_t;
+
+const char *font_choose_path(const char *explicit_font_path);
+int font_load(font_t *font, const char *path, float size_px);
+void font_free(font_t *font);
+
+void draw_text(font_t *font, float x, float y, const char *text);
+float text_width(font_t *font, const char *text);
+
+#endif
diff --git a/include/libccdjit.a b/include/libccdjit.a
new file mode 100644
index 0000000..3045696
--- /dev/null
+++ b/include/libccdjit.a
diff --git a/include/libccdjit.so b/include/libccdjit.so
new file mode 100755
index 0000000..40456db
--- /dev/null
+++ b/include/libccdjit.so
diff --git a/include/render.h b/include/render.h
new file mode 100644
index 0000000..f1a0a8c
--- /dev/null
+++ b/include/render.h
@@ -0,0 +1,8 @@
+#ifndef ECEX_RENDER_H
+#define ECEX_RENDER_H
+
+#include "app.h"
+
+void render(app_t *app);
+
+#endif
diff --git a/include/stb_truetype.h b/include/stb_truetype.h
new file mode 100644
index 0000000..90a5c2e
--- /dev/null
+++ b/include/stb_truetype.h
@@ -0,0 +1,5079 @@
+// stb_truetype.h - v1.26 - public domain
+// authored from 2009-2021 by Sean Barrett / RAD Game Tools
+//
+// =======================================================================
+//
+//    NO SECURITY GUARANTEE -- DO NOT USE THIS ON UNTRUSTED FONT FILES
+//
+// This library does no range checking of the offsets found in the file,
+// meaning an attacker can use it to read arbitrary memory.
+//
+// =======================================================================
+//
+//   This library processes TrueType files:
+//        parse files
+//        extract glyph metrics
+//        extract glyph shapes
+//        render glyphs to one-channel bitmaps with antialiasing (box filter)
+//        render glyphs to one-channel SDF bitmaps (signed-distance field/function)
+//
+//   Todo:
+//        non-MS cmaps
+//        crashproof on bad data
+//        hinting? (no longer patented)
+//        cleartype-style AA?
+//        optimize: use simple memory allocator for intermediates
+//        optimize: build edge-list directly from curves
+//        optimize: rasterize directly from curves?
+//
+// ADDITIONAL CONTRIBUTORS
+//
+//   Mikko Mononen: compound shape support, more cmap formats
+//   Tor Andersson: kerning, subpixel rendering
+//   Dougall Johnson: OpenType / Type 2 font handling
+//   Daniel Ribeiro Maciel: basic GPOS-based kerning
+//
+//   Misc other:
+//       Ryan Gordon
+//       Simon Glass
+//       github:IntellectualKitty
+//       Imanol Celaya
+//       Daniel Ribeiro Maciel
+//
+//   Bug/warning reports/fixes:
+//       "Zer" on mollyrocket       Fabian "ryg" Giesen   github:NiLuJe
+//       Cass Everitt               Martins Mozeiko       github:aloucks
+//       stoiko (Haemimont Games)   Cap Petschulat        github:oyvindjam
+//       Brian Hook                 Omar Cornut           github:vassvik
+//       Walter van Niftrik         Ryan Griege
+//       David Gow                  Peter LaValle
+//       David Given                Sergey Popov
+//       Ivan-Assen Ivanov          Giumo X. Clanjor
+//       Anthony Pesch              Higor Euripedes
+//       Johan Duparc               Thomas Fields
+//       Hou Qiming                 Derek Vinyard
+//       Rob Loach                  Cort Stratton
+//       Kenney Phillis Jr.         Brian Costabile
+//       Ken Voskuil (kaesve)       Yakov Galka
+//
+// VERSION HISTORY
+//
+//   1.26 (2021-08-28) fix broken rasterizer
+//   1.25 (2021-07-11) many fixes
+//   1.24 (2020-02-05) fix warning
+//   1.23 (2020-02-02) query SVG data for glyphs; query whole kerning table (but only kern not GPOS)
+//   1.22 (2019-08-11) minimize missing-glyph duplication; fix kerning if both 'GPOS' and 'kern' are defined
+//   1.21 (2019-02-25) fix warning
+//   1.20 (2019-02-07) PackFontRange skips missing codepoints; GetScaleFontVMetrics()
+//   1.19 (2018-02-11) GPOS kerning, STBTT_fmod
+//   1.18 (2018-01-29) add missing function
+//   1.17 (2017-07-23) make more arguments const; doc fix
+//   1.16 (2017-07-12) SDF support
+//   1.15 (2017-03-03) make more arguments const
+//   1.14 (2017-01-16) num-fonts-in-TTC function
+//   1.13 (2017-01-02) support OpenType fonts, certain Apple fonts
+//   1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual
+//   1.11 (2016-04-02) fix unused-variable warning
+//   1.10 (2016-04-02) user-defined fabs(); rare memory leak; remove duplicate typedef
+//   1.09 (2016-01-16) warning fix; avoid crash on outofmem; use allocation userdata properly
+//   1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges
+//   1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints;
+//                     variant PackFontRanges to pack and render in separate phases;
+//                     fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?);
+//                     fixed an assert() bug in the new rasterizer
+//                     replace assert() with STBTT_assert() in new rasterizer
+//
+//   Full history can be found at the end of this file.
+//
+// LICENSE
+//
+//   See end of file for license information.
+//
+// USAGE
+//
+//   Include this file in whatever places need to refer to it. In ONE C/C++
+//   file, write:
+//      #define STB_TRUETYPE_IMPLEMENTATION
+//   before the #include of this file. This expands out the actual
+//   implementation into that C/C++ file.
+//
+//   To make the implementation private to the file that generates the implementation,
+//      #define STBTT_STATIC
+//
+//   Simple 3D API (don't ship this, but it's fine for tools and quick start)
+//           stbtt_BakeFontBitmap()               -- bake a font to a bitmap for use as texture
+//           stbtt_GetBakedQuad()                 -- compute quad to draw for a given char
+//
+//   Improved 3D API (more shippable):
+//           #include "stb_rect_pack.h"           -- optional, but you really want it
+//           stbtt_PackBegin()
+//           stbtt_PackSetOversampling()          -- for improved quality on small fonts
+//           stbtt_PackFontRanges()               -- pack and renders
+//           stbtt_PackEnd()
+//           stbtt_GetPackedQuad()
+//
+//   "Load" a font file from a memory buffer (you have to keep the buffer loaded)
+//           stbtt_InitFont()
+//           stbtt_GetFontOffsetForIndex()        -- indexing for TTC font collections
+//           stbtt_GetNumberOfFonts()             -- number of fonts for TTC font collections
+//
+//   Render a unicode codepoint to a bitmap
+//           stbtt_GetCodepointBitmap()           -- allocates and returns a bitmap
+//           stbtt_MakeCodepointBitmap()          -- renders into bitmap you provide
+//           stbtt_GetCodepointBitmapBox()        -- how big the bitmap must be
+//
+//   Character advance/positioning
+//           stbtt_GetCodepointHMetrics()
+//           stbtt_GetFontVMetrics()
+//           stbtt_GetFontVMetricsOS2()
+//           stbtt_GetCodepointKernAdvance()
+//
+//   Starting with version 1.06, the rasterizer was replaced with a new,
+//   faster and generally-more-precise rasterizer. The new rasterizer more
+//   accurately measures pixel coverage for anti-aliasing, except in the case
+//   where multiple shapes overlap, in which case it overestimates the AA pixel
+//   coverage. Thus, anti-aliasing of intersecting shapes may look wrong. If
+//   this turns out to be a problem, you can re-enable the old rasterizer with
+//        #define STBTT_RASTERIZER_VERSION 1
+//   which will incur about a 15% speed hit.
+//
+// ADDITIONAL DOCUMENTATION
+//
+//   Immediately after this block comment are a series of sample programs.
+//
+//   After the sample programs is the "header file" section. This section
+//   includes documentation for each API function.
+//
+//   Some important concepts to understand to use this library:
+//
+//      Codepoint
+//         Characters are defined by unicode codepoints, e.g. 65 is
+//         uppercase A, 231 is lowercase c with a cedilla, 0x7e30 is
+//         the hiragana for "ma".
+//
+//      Glyph
+//         A visual character shape (every codepoint is rendered as
+//         some glyph)
+//
+//      Glyph index
+//         A font-specific integer ID representing a glyph
+//
+//      Baseline
+//         Glyph shapes are defined relative to a baseline, which is the
+//         bottom of uppercase characters. Characters extend both above
+//         and below the baseline.
+//
+//      Current Point
+//         As you draw text to the screen, you keep track of a "current point"
+//         which is the origin of each character. The current point's vertical
+//         position is the baseline. Even "baked fonts" use this model.
+//
+//      Vertical Font Metrics
+//         The vertical qualities of the font, used to vertically position
+//         and space the characters. See docs for stbtt_GetFontVMetrics.
+//
+//      Font Size in Pixels or Points
+//         The preferred interface for specifying font sizes in stb_truetype
+//         is to specify how tall the font's vertical extent should be in pixels.
+//         If that sounds good enough, skip the next paragraph.
+//
+//         Most font APIs instead use "points", which are a common typographic
+//         measurement for describing font size, defined as 72 points per inch.
+//         stb_truetype provides a point API for compatibility. However, true
+//         "per inch" conventions don't make much sense on computer displays
+//         since different monitors have different number of pixels per
+//         inch. For example, Windows traditionally uses a convention that
+//         there are 96 pixels per inch, thus making 'inch' measurements have
+//         nothing to do with inches, and thus effectively defining a point to
+//         be 1.333 pixels. Additionally, the TrueType font data provides
+//         an explicit scale factor to scale a given font's glyphs to points,
+//         but the author has observed that this scale factor is often wrong
+//         for non-commercial fonts, thus making fonts scaled in points
+//         according to the TrueType spec incoherently sized in practice.
+//
+// DETAILED USAGE:
+//
+//  Scale:
+//    Select how high you want the font to be, in points or pixels.
+//    Call ScaleForPixelHeight or ScaleForMappingEmToPixels to compute
+//    a scale factor SF that will be used by all other functions.
+//
+//  Baseline:
+//    You need to select a y-coordinate that is the baseline of where
+//    your text will appear. Call GetFontBoundingBox to get the baseline-relative
+//    bounding box for all characters. SF*-y0 will be the distance in pixels
+//    that the worst-case character could extend above the baseline, so if
+//    you want the top edge of characters to appear at the top of the
+//    screen where y=0, then you would set the baseline to SF*-y0.
+//
+//  Current point:
+//    Set the current point where the first character will appear. The
+//    first character could extend left of the current point; this is font
+//    dependent. You can either choose a current point that is the leftmost
+//    point and hope, or add some padding, or check the bounding box or
+//    left-side-bearing of the first character to be displayed and set
+//    the current point based on that.
+//
+//  Displaying a character:
+//    Compute the bounding box of the character. It will contain signed values
+//    relative to <current_point, baseline>. I.e. if it returns x0,y0,x1,y1,
+//    then the character should be displayed in the rectangle from
+//    <current_point+SF*x0, baseline+SF*y0> to <current_point+SF*x1,baseline+SF*y1).
+//
+//  Advancing for the next character:
+//    Call GlyphHMetrics, and compute 'current_point += SF * advance'.
+//
+//
+// ADVANCED USAGE
+//
+//   Quality:
+//
+//    - Use the functions with Subpixel at the end to allow your characters
+//      to have subpixel positioning. Since the font is anti-aliased, not
+//      hinted, this is very import for quality. (This is not possible with
+//      baked fonts.)
+//
+//    - Kerning is now supported, and if you're supporting subpixel rendering
+//      then kerning is worth using to give your text a polished look.
+//
+//   Performance:
+//
+//    - Convert Unicode codepoints to glyph indexes and operate on the glyphs;
+//      if you don't do this, stb_truetype is forced to do the conversion on
+//      every call.
+//
+//    - There are a lot of memory allocations. We should modify it to take
+//      a temp buffer and allocate from the temp buffer (without freeing),
+//      should help performance a lot.
+//
+// NOTES
+//
+//   The system uses the raw data found in the .ttf file without changing it
+//   and without building auxiliary data structures. This is a bit inefficient
+//   on little-endian systems (the data is big-endian), but assuming you're
+//   caching the bitmaps or glyph shapes this shouldn't be a big deal.
+//
+//   It appears to be very hard to programmatically determine what font a
+//   given file is in a general way. I provide an API for this, but I don't
+//   recommend it.
+//
+//
+// PERFORMANCE MEASUREMENTS FOR 1.06:
+//
+//                      32-bit     64-bit
+//   Previous release:  8.83 s     7.68 s
+//   Pool allocations:  7.72 s     6.34 s
+//   Inline sort     :  6.54 s     5.65 s
+//   New rasterizer  :  5.63 s     5.00 s
+
+//////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
+////
+////  SAMPLE PROGRAMS
+////
+//
+//  Incomplete text-in-3d-api example, which draws quads properly aligned to be lossless.
+//  See "tests/truetype_demo_win32.c" for a complete version.
+#if 0
+#define STB_TRUETYPE_IMPLEMENTATION  // force following include to generate implementation
+#include "stb_truetype.h"
+
+unsigned char ttf_buffer[1<<20];
+unsigned char temp_bitmap[512*512];
+
+stbtt_bakedchar cdata[96]; // ASCII 32..126 is 95 glyphs
+GLuint ftex;
+
+void my_stbtt_initfont(void)
+{
+   fread(ttf_buffer, 1, 1<<20, fopen("c:/windows/fonts/times.ttf", "rb"));
+   stbtt_BakeFontBitmap(ttf_buffer,0, 32.0, temp_bitmap,512,512, 32,96, cdata); // no guarantee this fits!
+   // can free ttf_buffer at this point
+   glGenTextures(1, &ftex);
+   glBindTexture(GL_TEXTURE_2D, ftex);
+   glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, 512,512, 0, GL_ALPHA, GL_UNSIGNED_BYTE, temp_bitmap);
+   // can free temp_bitmap at this point
+   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+}
+
+void my_stbtt_print(float x, float y, char *text)
+{
+   // assume orthographic projection with units = screen pixels, origin at top left
+   glEnable(GL_BLEND);
+   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+   glEnable(GL_TEXTURE_2D);
+   glBindTexture(GL_TEXTURE_2D, ftex);
+   glBegin(GL_QUADS);
+   while (*text) {
+      if (*text >= 32 && *text < 128) {
+         stbtt_aligned_quad q;
+         stbtt_GetBakedQuad(cdata, 512,512, *text-32, &x,&y,&q,1);//1=opengl & d3d10+,0=d3d9
+         glTexCoord2f(q.s0,q.t0); glVertex2f(q.x0,q.y0);
+         glTexCoord2f(q.s1,q.t0); glVertex2f(q.x1,q.y0);
+         glTexCoord2f(q.s1,q.t1); glVertex2f(q.x1,q.y1);
+         glTexCoord2f(q.s0,q.t1); glVertex2f(q.x0,q.y1);
+      }
+      ++text;
+   }
+   glEnd();
+}
+#endif
+//
+//
+//////////////////////////////////////////////////////////////////////////////
+//
+// Complete program (this compiles): get a single bitmap, print as ASCII art
+//
+#if 0
+#include <stdio.h>
+#define STB_TRUETYPE_IMPLEMENTATION  // force following include to generate implementation
+#include "stb_truetype.h"
+
+char ttf_buffer[1<<25];
+
+int main(int argc, char **argv)
+{
+   stbtt_fontinfo font;
+   unsigned char *bitmap;
+   int w,h,i,j,c = (argc > 1 ? atoi(argv[1]) : 'a'), s = (argc > 2 ? atoi(argv[2]) : 20);
+
+   fread(ttf_buffer, 1, 1<<25, fopen(argc > 3 ? argv[3] : "c:/windows/fonts/arialbd.ttf", "rb"));
+
+   stbtt_InitFont(&font, ttf_buffer, stbtt_GetFontOffsetForIndex(ttf_buffer,0));
+   bitmap = stbtt_GetCodepointBitmap(&font, 0,stbtt_ScaleForPixelHeight(&font, s), c, &w, &h, 0,0);
+
+   for (j=0; j < h; ++j) {
+      for (i=0; i < w; ++i)
+         putchar(" .:ioVM@"[bitmap[j*w+i]>>5]);
+      putchar('\n');
+   }
+   return 0;
+}
+#endif
+//
+// Output:
+//
+//     .ii.
+//    @@@@@@.
+//   V@Mio@@o
+//   :i.  V@V
+//     :oM@@M
+//   :@@@MM@M
+//   @@o  o@M
+//  :@@.  M@M
+//   @@@o@@@@
+//   :M@@V:@@.
+//
+//////////////////////////////////////////////////////////////////////////////
+//
+// Complete program: print "Hello World!" banner, with bugs
+//
+#if 0
+char buffer[24<<20];
+unsigned char screen[20][79];
+
+int main(int arg, char **argv)
+{
+   stbtt_fontinfo font;
+   int i,j,ascent,baseline,ch=0;
+   float scale, xpos=2; // leave a little padding in case the character extends left
+   char *text = "Heljo World!"; // intentionally misspelled to show 'lj' brokenness
+
+   fread(buffer, 1, 1000000, fopen("c:/windows/fonts/arialbd.ttf", "rb"));
+   stbtt_InitFont(&font, buffer, 0);
+
+   scale = stbtt_ScaleForPixelHeight(&font, 15);
+   stbtt_GetFontVMetrics(&font, &ascent,0,0);
+   baseline = (int) (ascent*scale);
+
+   while (text[ch]) {
+      int advance,lsb,x0,y0,x1,y1;
+      float x_shift = xpos - (float) floor(xpos);
+      stbtt_GetCodepointHMetrics(&font, text[ch], &advance, &lsb);
+      stbtt_GetCodepointBitmapBoxSubpixel(&font, text[ch], scale,scale,x_shift,0, &x0,&y0,&x1,&y1);
+      stbtt_MakeCodepointBitmapSubpixel(&font, &screen[baseline + y0][(int) xpos + x0], x1-x0,y1-y0, 79, scale,scale,x_shift,0, text[ch]);
+      // note that this stomps the old data, so where character boxes overlap (e.g. 'lj') it's wrong
+      // because this API is really for baking character bitmaps into textures. if you want to render
+      // a sequence of characters, you really need to render each bitmap to a temp buffer, then
+      // "alpha blend" that into the working buffer
+      xpos += (advance * scale);
+      if (text[ch+1])
+         xpos += scale*stbtt_GetCodepointKernAdvance(&font, text[ch],text[ch+1]);
+      ++ch;
+   }
+
+   for (j=0; j < 20; ++j) {
+      for (i=0; i < 78; ++i)
+         putchar(" .:ioVM@"[screen[j][i]>>5]);
+      putchar('\n');
+   }
+
+   return 0;
+}
+#endif
+
+
+//////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
+////
+////   INTEGRATION WITH YOUR CODEBASE
+////
+////   The following sections allow you to supply alternate definitions
+////   of C library functions used by stb_truetype, e.g. if you don't
+////   link with the C runtime library.
+
+#ifdef STB_TRUETYPE_IMPLEMENTATION
+   // #define your own (u)stbtt_int8/16/32 before including to override this
+   #ifndef stbtt_uint8
+   typedef unsigned char   stbtt_uint8;
+   typedef signed   char   stbtt_int8;
+   typedef unsigned short  stbtt_uint16;
+   typedef signed   short  stbtt_int16;
+   typedef unsigned int    stbtt_uint32;
+   typedef signed   int    stbtt_int32;
+   #endif
+
+   typedef char stbtt__check_size32[sizeof(stbtt_int32)==4 ? 1 : -1];
+   typedef char stbtt__check_size16[sizeof(stbtt_int16)==2 ? 1 : -1];
+
+   // e.g. #define your own STBTT_ifloor/STBTT_iceil() to avoid math.h
+   #ifndef STBTT_ifloor
+   #include <math.h>
+   #define STBTT_ifloor(x)   ((int) floor(x))
+   #define STBTT_iceil(x)    ((int) ceil(x))
+   #endif
+
+   #ifndef STBTT_sqrt
+   #include <math.h>
+   #define STBTT_sqrt(x)      sqrt(x)
+   #define STBTT_pow(x,y)     pow(x,y)
+   #endif
+
+   #ifndef STBTT_fmod
+   #include <math.h>
+   #define STBTT_fmod(x,y)    fmod(x,y)
+   #endif
+
+   #ifndef STBTT_cos
+   #include <math.h>
+   #define STBTT_cos(x)       cos(x)
+   #define STBTT_acos(x)      acos(x)
+   #endif
+
+   #ifndef STBTT_fabs
+   #include <math.h>
+   #define STBTT_fabs(x)      fabs(x)
+   #endif
+
+   // #define your own functions "STBTT_malloc" / "STBTT_free" to avoid malloc.h
+   #ifndef STBTT_malloc
+   #include <stdlib.h>
+   #define STBTT_malloc(x,u)  ((void)(u),malloc(x))
+   #define STBTT_free(x,u)    ((void)(u),free(x))
+   #endif
+
+   #ifndef STBTT_assert
+   #include <assert.h>
+   #define STBTT_assert(x)    assert(x)
+   #endif
+
+   #ifndef STBTT_strlen
+   #include <string.h>
+   #define STBTT_strlen(x)    strlen(x)
+   #endif
+
+   #ifndef STBTT_memcpy
+   #include <string.h>
+   #define STBTT_memcpy       memcpy
+   #define STBTT_memset       memset
+   #endif
+#endif
+
+///////////////////////////////////////////////////////////////////////////////
+///////////////////////////////////////////////////////////////////////////////
+////
+////   INTERFACE
+////
+////
+
+#ifndef __STB_INCLUDE_STB_TRUETYPE_H__
+#define __STB_INCLUDE_STB_TRUETYPE_H__
+
+#ifdef STBTT_STATIC
+#define STBTT_DEF static
+#else
+#define STBTT_DEF extern
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// private structure
+typedef struct
+{
+   unsigned char *data;
+   int cursor;
+   int size;
+} stbtt__buf;
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// TEXTURE BAKING API
+//
+// If you use this API, you only have to call two functions ever.
+//
+
+typedef struct
+{
+   unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap
+   float xoff,yoff,xadvance;
+} stbtt_bakedchar;
+
+STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset,  // font location (use offset=0 for plain .ttf)
+                                float pixel_height,                     // height of font in pixels
+                                unsigned char *pixels, int pw, int ph,  // bitmap to be filled in
+                                int first_char, int num_chars,          // characters to bake
+                                stbtt_bakedchar *chardata);             // you allocate this, it's num_chars long
+// if return is positive, the first unused row of the bitmap
+// if return is negative, returns the negative of the number of characters that fit
+// if return is 0, no characters fit and no rows were used
+// This uses a very crappy packing.
+
+typedef struct
+{
+   float x0,y0,s0,t0; // top-left
+   float x1,y1,s1,t1; // bottom-right
+} stbtt_aligned_quad;
+
+STBTT_DEF void stbtt_GetBakedQuad(const stbtt_bakedchar *chardata, int pw, int ph,  // same data as above
+                               int char_index,             // character to display
+                               float *xpos, float *ypos,   // pointers to current position in screen pixel space
+                               stbtt_aligned_quad *q,      // output: quad to draw
+                               int opengl_fillrule);       // true if opengl fill rule; false if DX9 or earlier
+// Call GetBakedQuad with char_index = 'character - first_char', and it
+// creates the quad you need to draw and advances the current position.
+//
+// The coordinate system used assumes y increases downwards.
+//
+// Characters will extend both above and below the current position;
+// see discussion of "BASELINE" above.
+//
+// It's inefficient; you might want to c&p it and optimize it.
+
+STBTT_DEF void stbtt_GetScaledFontVMetrics(const unsigned char *fontdata, int index, float size, float *ascent, float *descent, float *lineGap);
+// Query the font vertical metrics without having to create a font first.
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// NEW TEXTURE BAKING API
+//
+// This provides options for packing multiple fonts into one atlas, not
+// perfectly but better than nothing.
+
+typedef struct
+{
+   unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap
+   float xoff,yoff,xadvance;
+   float xoff2,yoff2;
+} stbtt_packedchar;
+
+typedef struct stbtt_pack_context stbtt_pack_context;
+typedef struct stbtt_fontinfo stbtt_fontinfo;
+#ifndef STB_RECT_PACK_VERSION
+typedef struct stbrp_rect stbrp_rect;
+#endif
+
+STBTT_DEF int  stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int width, int height, int stride_in_bytes, int padding, void *alloc_context);
+// Initializes a packing context stored in the passed-in stbtt_pack_context.
+// Future calls using this context will pack characters into the bitmap passed
+// in here: a 1-channel bitmap that is width * height. stride_in_bytes is
+// the distance from one row to the next (or 0 to mean they are packed tightly
+// together). "padding" is the amount of padding to leave between each
+// character (normally you want '1' for bitmaps you'll use as textures with
+// bilinear filtering).
+//
+// Returns 0 on failure, 1 on success.
+
+STBTT_DEF void stbtt_PackEnd  (stbtt_pack_context *spc);
+// Cleans up the packing context and frees all memory.
+
+#define STBTT_POINT_SIZE(x)   (-(x))
+
+STBTT_DEF int  stbtt_PackFontRange(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, float font_size,
+                                int first_unicode_char_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range);
+// Creates character bitmaps from the font_index'th font found in fontdata (use
+// font_index=0 if you don't know what that is). It creates num_chars_in_range
+// bitmaps for characters with unicode values starting at first_unicode_char_in_range
+// and increasing. Data for how to render them is stored in chardata_for_range;
+// pass these to stbtt_GetPackedQuad to get back renderable quads.
+//
+// font_size is the full height of the character from ascender to descender,
+// as computed by stbtt_ScaleForPixelHeight. To use a point size as computed
+// by stbtt_ScaleForMappingEmToPixels, wrap the point size in STBTT_POINT_SIZE()
+// and pass that result as 'font_size':
+//       ...,                  20 , ... // font max minus min y is 20 pixels tall
+//       ..., STBTT_POINT_SIZE(20), ... // 'M' is 20 pixels tall
+
+typedef struct
+{
+   float font_size;
+   int first_unicode_codepoint_in_range;  // if non-zero, then the chars are continuous, and this is the first codepoint
+   int *array_of_unicode_codepoints;       // if non-zero, then this is an array of unicode codepoints
+   int num_chars;
+   stbtt_packedchar *chardata_for_range; // output
+   unsigned char h_oversample, v_oversample; // don't set these, they're used internally
+} stbtt_pack_range;
+
+STBTT_DEF int  stbtt_PackFontRanges(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges);
+// Creates character bitmaps from multiple ranges of characters stored in
+// ranges. This will usually create a better-packed bitmap than multiple
+// calls to stbtt_PackFontRange. Note that you can call this multiple
+// times within a single PackBegin/PackEnd.
+
+STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample);
+// Oversampling a font increases the quality by allowing higher-quality subpixel
+// positioning, and is especially valuable at smaller text sizes.
+//
+// This function sets the amount of oversampling for all following calls to
+// stbtt_PackFontRange(s) or stbtt_PackFontRangesGatherRects for a given
+// pack context. The default (no oversampling) is achieved by h_oversample=1
+// and v_oversample=1. The total number of pixels required is
+// h_oversample*v_oversample larger than the default; for example, 2x2
+// oversampling requires 4x the storage of 1x1. For best results, render
+// oversampled textures with bilinear filtering. Look at the readme in
+// stb/tests/oversample for information about oversampled fonts
+//
+// To use with PackFontRangesGather etc., you must set it before calls
+// call to PackFontRangesGatherRects.
+
+STBTT_DEF void stbtt_PackSetSkipMissingCodepoints(stbtt_pack_context *spc, int skip);
+// If skip != 0, this tells stb_truetype to skip any codepoints for which
+// there is no corresponding glyph. If skip=0, which is the default, then
+// codepoints without a glyph recived the font's "missing character" glyph,
+// typically an empty box by convention.
+
+STBTT_DEF void stbtt_GetPackedQuad(const stbtt_packedchar *chardata, int pw, int ph,  // same data as above
+                               int char_index,             // character to display
+                               float *xpos, float *ypos,   // pointers to current position in screen pixel space
+                               stbtt_aligned_quad *q,      // output: quad to draw
+                               int align_to_integer);
+
+STBTT_DEF int  stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects);
+STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects);
+STBTT_DEF int  stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects);
+// Calling these functions in sequence is roughly equivalent to calling
+// stbtt_PackFontRanges(). If you more control over the packing of multiple
+// fonts, or if you want to pack custom data into a font texture, take a look
+// at the source to of stbtt_PackFontRanges() and create a custom version
+// using these functions, e.g. call GatherRects multiple times,
+// building up a single array of rects, then call PackRects once,
+// then call RenderIntoRects repeatedly. This may result in a
+// better packing than calling PackFontRanges multiple times
+// (or it may not).
+
+// this is an opaque structure that you shouldn't mess with which holds
+// all the context needed from PackBegin to PackEnd.
+struct stbtt_pack_context {
+   void *user_allocator_context;
+   void *pack_info;
+   int   width;
+   int   height;
+   int   stride_in_bytes;
+   int   padding;
+   int   skip_missing;
+   unsigned int   h_oversample, v_oversample;
+   unsigned char *pixels;
+   void  *nodes;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// FONT LOADING
+//
+//
+
+STBTT_DEF int stbtt_GetNumberOfFonts(const unsigned char *data);
+// This function will determine the number of fonts in a font file.  TrueType
+// collection (.ttc) files may contain multiple fonts, while TrueType font
+// (.ttf) files only contain one font. The number of fonts can be used for
+// indexing with the previous function where the index is between zero and one
+// less than the total fonts. If an error occurs, -1 is returned.
+
+STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index);
+// Each .ttf/.ttc file may have more than one font. Each font has a sequential
+// index number starting from 0. Call this function to get the font offset for
+// a given index; it returns -1 if the index is out of range. A regular .ttf
+// file will only define one font and it always be at offset 0, so it will
+// return '0' for index 0, and -1 for all other indices.
+
+// The following structure is defined publicly so you can declare one on
+// the stack or as a global or etc, but you should treat it as opaque.
+struct stbtt_fontinfo
+{
+   void           * userdata;
+   unsigned char  * data;              // pointer to .ttf file
+   int              fontstart;         // offset of start of font
+
+   int numGlyphs;                     // number of glyphs, needed for range checking
+
+   int loca,head,glyf,hhea,hmtx,kern,gpos,svg; // table locations as offset from start of .ttf
+   int index_map;                     // a cmap mapping for our chosen character encoding
+   int indexToLocFormat;              // format needed to map from glyph index to glyph
+
+   stbtt__buf cff;                    // cff font data
+   stbtt__buf charstrings;            // the charstring index
+   stbtt__buf gsubrs;                 // global charstring subroutines index
+   stbtt__buf subrs;                  // private charstring subroutines index
+   stbtt__buf fontdicts;              // array of font dicts
+   stbtt__buf fdselect;               // map from glyph to fontdict
+};
+
+STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset);
+// Given an offset into the file that defines a font, this function builds
+// the necessary cached info for the rest of the system. You must allocate
+// the stbtt_fontinfo yourself, and stbtt_InitFont will fill it out. You don't
+// need to do anything special to free it, because the contents are pure
+// value data with no additional data structures. Returns 0 on failure.
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// CHARACTER TO GLYPH-INDEX CONVERSIOn
+
+STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint);
+// If you're going to perform multiple operations on the same character
+// and you want a speed-up, call this function with the character you're
+// going to process, then use glyph-based functions instead of the
+// codepoint-based functions.
+// Returns 0 if the character codepoint is not defined in the font.
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// CHARACTER PROPERTIES
+//
+
+STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float pixels);
+// computes a scale factor to produce a font whose "height" is 'pixels' tall.
+// Height is measured as the distance from the highest ascender to the lowest
+// descender; in other words, it's equivalent to calling stbtt_GetFontVMetrics
+// and computing:
+//       scale = pixels / (ascent - descent)
+// so if you prefer to measure height by the ascent only, use a similar calculation.
+
+STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels);
+// computes a scale factor to produce a font whose EM size is mapped to
+// 'pixels' tall. This is probably what traditional APIs compute, but
+// I'm not positive.
+
+STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap);
+// ascent is the coordinate above the baseline the font extends; descent
+// is the coordinate below the baseline the font extends (i.e. it is typically negative)
+// lineGap is the spacing between one row's descent and the next row's ascent...
+// so you should advance the vertical position by "*ascent - *descent + *lineGap"
+//   these are expressed in unscaled coordinates, so you must multiply by
+//   the scale factor for a given size
+
+STBTT_DEF int  stbtt_GetFontVMetricsOS2(const stbtt_fontinfo *info, int *typoAscent, int *typoDescent, int *typoLineGap);
+// analogous to GetFontVMetrics, but returns the "typographic" values from the OS/2
+// table (specific to MS/Windows TTF files).
+//
+// Returns 1 on success (table present), 0 on failure.
+
+STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1);
+// the bounding box around all possible characters
+
+STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing);
+// leftSideBearing is the offset from the current horizontal position to the left edge of the character
+// advanceWidth is the offset from the current horizontal position to the next horizontal position
+//   these are expressed in unscaled coordinates
+
+STBTT_DEF int  stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2);
+// an additional amount to add to the 'advance' value between ch1 and ch2
+
+STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1);
+// Gets the bounding box of the visible part of the glyph, in unscaled coordinates
+
+STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing);
+STBTT_DEF int  stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2);
+STBTT_DEF int  stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);
+// as above, but takes one or more glyph indices for greater efficiency
+
+typedef struct stbtt_kerningentry
+{
+   int glyph1; // use stbtt_FindGlyphIndex
+   int glyph2;
+   int advance;
+} stbtt_kerningentry;
+
+STBTT_DEF int  stbtt_GetKerningTableLength(const stbtt_fontinfo *info);
+STBTT_DEF int  stbtt_GetKerningTable(const stbtt_fontinfo *info, stbtt_kerningentry* table, int table_length);
+// Retrieves a complete list of all of the kerning pairs provided by the font
+// stbtt_GetKerningTable never writes more than table_length entries and returns how many entries it did write.
+// The table will be sorted by (a.glyph1 == b.glyph1)?(a.glyph2 < b.glyph2):(a.glyph1 < b.glyph1)
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// GLYPH SHAPES (you probably don't need these, but they have to go before
+// the bitmaps for C declaration-order reasons)
+//
+
+#ifndef STBTT_vmove // you can predefine these to use different values (but why?)
+   enum {
+      STBTT_vmove=1,
+      STBTT_vline,
+      STBTT_vcurve,
+      STBTT_vcubic
+   };
+#endif
+
+#ifndef stbtt_vertex // you can predefine this to use different values
+                   // (we share this with other code at RAD)
+   #define stbtt_vertex_type short // can't use stbtt_int16 because that's not visible in the header file
+   typedef struct
+   {
+      stbtt_vertex_type x,y,cx,cy,cx1,cy1;
+      unsigned char type,padding;
+   } stbtt_vertex;
+#endif
+
+STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index);
+// returns non-zero if nothing is drawn for this glyph
+
+STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices);
+STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **vertices);
+// returns # of vertices and fills *vertices with the pointer to them
+//   these are expressed in "unscaled" coordinates
+//
+// The shape is a series of contours. Each one starts with
+// a STBTT_moveto, then consists of a series of mixed
+// STBTT_lineto and STBTT_curveto segments. A lineto
+// draws a line from previous endpoint to its x,y; a curveto
+// draws a quadratic bezier from previous endpoint to
+// its x,y, using cx,cy as the bezier control point.
+
+STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *vertices);
+// frees the data allocated above
+
+STBTT_DEF unsigned char *stbtt_FindSVGDoc(const stbtt_fontinfo *info, int gl);
+STBTT_DEF int stbtt_GetCodepointSVG(const stbtt_fontinfo *info, int unicode_codepoint, const char **svg);
+STBTT_DEF int stbtt_GetGlyphSVG(const stbtt_fontinfo *info, int gl, const char **svg);
+// fills svg with the character's SVG data.
+// returns data size or 0 if SVG not found.
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// BITMAP RENDERING
+//
+
+STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata);
+// frees the bitmap allocated below
+
+STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
+// allocates a large-enough single-channel 8bpp bitmap and renders the
+// specified character/glyph at the specified scale into it, with
+// antialiasing. 0 is no coverage (transparent), 255 is fully covered (opaque).
+// *width & *height are filled out with the width & height of the bitmap,
+// which is stored left-to-right, top-to-bottom.
+//
+// xoff/yoff are the offset it pixel space from the glyph origin to the top-left of the bitmap
+
+STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
+// the same as stbtt_GetCodepoitnBitmap, but you can specify a subpixel
+// shift for the character
+
+STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint);
+// the same as stbtt_GetCodepointBitmap, but you pass in storage for the bitmap
+// in the form of 'output', with row spacing of 'out_stride' bytes. the bitmap
+// is clipped to out_w/out_h bytes. Call stbtt_GetCodepointBitmapBox to get the
+// width and height and positioning info for it first.
+
+STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint);
+// same as stbtt_MakeCodepointBitmap, but you can specify a subpixel
+// shift for the character
+
+STBTT_DEF void stbtt_MakeCodepointBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int codepoint);
+// same as stbtt_MakeCodepointBitmapSubpixel, but prefiltering
+// is performed (see stbtt_PackSetOversampling)
+
+STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
+// get the bbox of the bitmap centered around the glyph origin; so the
+// bitmap width is ix1-ix0, height is iy1-iy0, and location to place
+// the bitmap top left is (leftSideBearing*scale,iy0).
+// (Note that the bitmap uses y-increases-down, but the shape uses
+// y-increases-up, so CodepointBitmapBox and CodepointBox are inverted.)
+
+STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1);
+// same as stbtt_GetCodepointBitmapBox, but you can specify a subpixel
+// shift for the character
+
+// the following functions are equivalent to the above functions, but operate
+// on glyph indices instead of Unicode codepoints (for efficiency)
+STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff);
+STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff);
+STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph);
+STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph);
+STBTT_DEF void stbtt_MakeGlyphBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int glyph);
+STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
+STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y,float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1);
+
+
+// @TODO: don't expose this structure
+typedef struct
+{
+   int w,h,stride;
+   unsigned char *pixels;
+} stbtt__bitmap;
+
+// rasterize a shape with quadratic beziers into a bitmap
+STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result,        // 1-channel bitmap to draw into
+                               float flatness_in_pixels,     // allowable error of curve in pixels
+                               stbtt_vertex *vertices,       // array of vertices defining shape
+                               int num_verts,                // number of vertices in above array
+                               float scale_x, float scale_y, // scale applied to input vertices
+                               float shift_x, float shift_y, // translation applied to input vertices
+                               int x_off, int y_off,         // another translation applied to input
+                               int invert,                   // if non-zero, vertically flip shape
+                               void *userdata);              // context for to STBTT_MALLOC
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Signed Distance Function (or Field) rendering
+
+STBTT_DEF void stbtt_FreeSDF(unsigned char *bitmap, void *userdata);
+// frees the SDF bitmap allocated below
+
+STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float scale, int glyph, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff);
+STBTT_DEF unsigned char * stbtt_GetCodepointSDF(const stbtt_fontinfo *info, float scale, int codepoint, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff);
+// These functions compute a discretized SDF field for a single character, suitable for storing
+// in a single-channel texture, sampling with bilinear filtering, and testing against
+// larger than some threshold to produce scalable fonts.
+//        info              --  the font
+//        scale             --  controls the size of the resulting SDF bitmap, same as it would be creating a regular bitmap
+//        glyph/codepoint   --  the character to generate the SDF for
+//        padding           --  extra "pixels" around the character which are filled with the distance to the character (not 0),
+//                                 which allows effects like bit outlines
+//        onedge_value      --  value 0-255 to test the SDF against to reconstruct the character (i.e. the isocontour of the character)
+//        pixel_dist_scale  --  what value the SDF should increase by when moving one SDF "pixel" away from the edge (on the 0..255 scale)
+//                                 if positive, > onedge_value is inside; if negative, < onedge_value is inside
+//        width,height      --  output height & width of the SDF bitmap (including padding)
+//        xoff,yoff         --  output origin of the character
+//        return value      --  a 2D array of bytes 0..255, width*height in size
+//
+// pixel_dist_scale & onedge_value are a scale & bias that allows you to make
+// optimal use of the limited 0..255 for your application, trading off precision
+// and special effects. SDF values outside the range 0..255 are clamped to 0..255.
+//
+// Example:
+//      scale = stbtt_ScaleForPixelHeight(22)
+//      padding = 5
+//      onedge_value = 180
+//      pixel_dist_scale = 180/5.0 = 36.0
+//
+//      This will create an SDF bitmap in which the character is about 22 pixels
+//      high but the whole bitmap is about 22+5+5=32 pixels high. To produce a filled
+//      shape, sample the SDF at each pixel and fill the pixel if the SDF value
+//      is greater than or equal to 180/255. (You'll actually want to antialias,
+//      which is beyond the scope of this example.) Additionally, you can compute
+//      offset outlines (e.g. to stroke the character border inside & outside,
+//      or only outside). For example, to fill outside the character up to 3 SDF
+//      pixels, you would compare against (180-36.0*3)/255 = 72/255. The above
+//      choice of variables maps a range from 5 pixels outside the shape to
+//      2 pixels inside the shape to 0..255; this is intended primarily for apply
+//      outside effects only (the interior range is needed to allow proper
+//      antialiasing of the font at *smaller* sizes)
+//
+// The function computes the SDF analytically at each SDF pixel, not by e.g.
+// building a higher-res bitmap and approximating it. In theory the quality
+// should be as high as possible for an SDF of this size & representation, but
+// unclear if this is true in practice (perhaps building a higher-res bitmap
+// and computing from that can allow drop-out prevention).
+//
+// The algorithm has not been optimized at all, so expect it to be slow
+// if computing lots of characters or very large sizes.
+
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Finding the right font...
+//
+// You should really just solve this offline, keep your own tables
+// of what font is what, and don't try to get it out of the .ttf file.
+// That's because getting it out of the .ttf file is really hard, because
+// the names in the file can appear in many possible encodings, in many
+// possible languages, and e.g. if you need a case-insensitive comparison,
+// the details of that depend on the encoding & language in a complex way
+// (actually underspecified in truetype, but also gigantic).
+//
+// But you can use the provided functions in two possible ways:
+//     stbtt_FindMatchingFont() will use *case-sensitive* comparisons on
+//             unicode-encoded names to try to find the font you want;
+//             you can run this before calling stbtt_InitFont()
+//
+//     stbtt_GetFontNameString() lets you get any of the various strings
+//             from the file yourself and do your own comparisons on them.
+//             You have to have called stbtt_InitFont() first.
+
+
+STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags);
+// returns the offset (not index) of the font that matches, or -1 if none
+//   if you use STBTT_MACSTYLE_DONTCARE, use a font name like "Arial Bold".
+//   if you use any other flag, use a font name like "Arial"; this checks
+//     the 'macStyle' header field; i don't know if fonts set this consistently
+#define STBTT_MACSTYLE_DONTCARE     0
+#define STBTT_MACSTYLE_BOLD         1
+#define STBTT_MACSTYLE_ITALIC       2
+#define STBTT_MACSTYLE_UNDERSCORE   4
+#define STBTT_MACSTYLE_NONE         8   // <= not same as 0, this makes us check the bitfield is 0
+
+STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2);
+// returns 1/0 whether the first string interpreted as utf8 is identical to
+// the second string interpreted as big-endian utf16... useful for strings from next func
+
+STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID);
+// returns the string (which may be big-endian double byte, e.g. for unicode)
+// and puts the length in bytes in *length.
+//
+// some of the values for the IDs are below; for more see the truetype spec:
+//     http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6name.html
+//     http://www.microsoft.com/typography/otspec/name.htm
+
+enum { // platformID
+   STBTT_PLATFORM_ID_UNICODE   =0,
+   STBTT_PLATFORM_ID_MAC       =1,
+   STBTT_PLATFORM_ID_ISO       =2,
+   STBTT_PLATFORM_ID_MICROSOFT =3
+};
+
+enum { // encodingID for STBTT_PLATFORM_ID_UNICODE
+   STBTT_UNICODE_EID_UNICODE_1_0    =0,
+   STBTT_UNICODE_EID_UNICODE_1_1    =1,
+   STBTT_UNICODE_EID_ISO_10646      =2,
+   STBTT_UNICODE_EID_UNICODE_2_0_BMP=3,
+   STBTT_UNICODE_EID_UNICODE_2_0_FULL=4
+};
+
+enum { // encodingID for STBTT_PLATFORM_ID_MICROSOFT
+   STBTT_MS_EID_SYMBOL        =0,
+   STBTT_MS_EID_UNICODE_BMP   =1,
+   STBTT_MS_EID_SHIFTJIS      =2,
+   STBTT_MS_EID_UNICODE_FULL  =10
+};
+
+enum { // encodingID for STBTT_PLATFORM_ID_MAC; same as Script Manager codes
+   STBTT_MAC_EID_ROMAN        =0,   STBTT_MAC_EID_ARABIC       =4,
+   STBTT_MAC_EID_JAPANESE     =1,   STBTT_MAC_EID_HEBREW       =5,
+   STBTT_MAC_EID_CHINESE_TRAD =2,   STBTT_MAC_EID_GREEK        =6,
+   STBTT_MAC_EID_KOREAN       =3,   STBTT_MAC_EID_RUSSIAN      =7
+};
+
+enum { // languageID for STBTT_PLATFORM_ID_MICROSOFT; same as LCID...
+       // problematic because there are e.g. 16 english LCIDs and 16 arabic LCIDs
+   STBTT_MS_LANG_ENGLISH     =0x0409,   STBTT_MS_LANG_ITALIAN     =0x0410,
+   STBTT_MS_LANG_CHINESE     =0x0804,   STBTT_MS_LANG_JAPANESE    =0x0411,
+   STBTT_MS_LANG_DUTCH       =0x0413,   STBTT_MS_LANG_KOREAN      =0x0412,
+   STBTT_MS_LANG_FRENCH      =0x040c,   STBTT_MS_LANG_RUSSIAN     =0x0419,
+   STBTT_MS_LANG_GERMAN      =0x0407,   STBTT_MS_LANG_SPANISH     =0x0409,
+   STBTT_MS_LANG_HEBREW      =0x040d,   STBTT_MS_LANG_SWEDISH     =0x041D
+};
+
+enum { // languageID for STBTT_PLATFORM_ID_MAC
+   STBTT_MAC_LANG_ENGLISH      =0 ,   STBTT_MAC_LANG_JAPANESE     =11,
+   STBTT_MAC_LANG_ARABIC       =12,   STBTT_MAC_LANG_KOREAN       =23,
+   STBTT_MAC_LANG_DUTCH        =4 ,   STBTT_MAC_LANG_RUSSIAN      =32,
+   STBTT_MAC_LANG_FRENCH       =1 ,   STBTT_MAC_LANG_SPANISH      =6 ,
+   STBTT_MAC_LANG_GERMAN       =2 ,   STBTT_MAC_LANG_SWEDISH      =5 ,
+   STBTT_MAC_LANG_HEBREW       =10,   STBTT_MAC_LANG_CHINESE_SIMPLIFIED =33,
+   STBTT_MAC_LANG_ITALIAN      =3 ,   STBTT_MAC_LANG_CHINESE_TRAD =19
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // __STB_INCLUDE_STB_TRUETYPE_H__
+
+///////////////////////////////////////////////////////////////////////////////
+///////////////////////////////////////////////////////////////////////////////
+////
+////   IMPLEMENTATION
+////
+////
+
+#ifdef STB_TRUETYPE_IMPLEMENTATION
+
+#ifndef STBTT_MAX_OVERSAMPLE
+#define STBTT_MAX_OVERSAMPLE   8
+#endif
+
+#if STBTT_MAX_OVERSAMPLE > 255
+#error "STBTT_MAX_OVERSAMPLE cannot be > 255"
+#endif
+
+typedef int stbtt__test_oversample_pow2[(STBTT_MAX_OVERSAMPLE & (STBTT_MAX_OVERSAMPLE-1)) == 0 ? 1 : -1];
+
+#ifndef STBTT_RASTERIZER_VERSION
+#define STBTT_RASTERIZER_VERSION 2
+#endif
+
+#ifdef _MSC_VER
+#define STBTT__NOTUSED(v)  (void)(v)
+#else
+#define STBTT__NOTUSED(v)  (void)sizeof(v)
+#endif
+
+//////////////////////////////////////////////////////////////////////////
+//
+// stbtt__buf helpers to parse data from file
+//
+
+static stbtt_uint8 stbtt__buf_get8(stbtt__buf *b)
+{
+   if (b->cursor >= b->size)
+      return 0;
+   return b->data[b->cursor++];
+}
+
+static stbtt_uint8 stbtt__buf_peek8(stbtt__buf *b)
+{
+   if (b->cursor >= b->size)
+      return 0;
+   return b->data[b->cursor];
+}
+
+static void stbtt__buf_seek(stbtt__buf *b, int o)
+{
+   STBTT_assert(!(o > b->size || o < 0));
+   b->cursor = (o > b->size || o < 0) ? b->size : o;
+}
+
+static void stbtt__buf_skip(stbtt__buf *b, int o)
+{
+   stbtt__buf_seek(b, b->cursor + o);
+}
+
+static stbtt_uint32 stbtt__buf_get(stbtt__buf *b, int n)
+{
+   stbtt_uint32 v = 0;
+   int i;
+   STBTT_assert(n >= 1 && n <= 4);
+   for (i = 0; i < n; i++)
+      v = (v << 8) | stbtt__buf_get8(b);
+   return v;
+}
+
+static stbtt__buf stbtt__new_buf(const void *p, size_t size)
+{
+   stbtt__buf r;
+   STBTT_assert(size < 0x40000000);
+   r.data = (stbtt_uint8*) p;
+   r.size = (int) size;
+   r.cursor = 0;
+   return r;
+}
+
+#define stbtt__buf_get16(b)  stbtt__buf_get((b), 2)
+#define stbtt__buf_get32(b)  stbtt__buf_get((b), 4)
+
+static stbtt__buf stbtt__buf_range(const stbtt__buf *b, int o, int s)
+{
+   stbtt__buf r = stbtt__new_buf(NULL, 0);
+   if (o < 0 || s < 0 || o > b->size || s > b->size - o) return r;
+   r.data = b->data + o;
+   r.size = s;
+   return r;
+}
+
+static stbtt__buf stbtt__cff_get_index(stbtt__buf *b)
+{
+   int count, start, offsize;
+   start = b->cursor;
+   count = stbtt__buf_get16(b);
+   if (count) {
+      offsize = stbtt__buf_get8(b);
+      STBTT_assert(offsize >= 1 && offsize <= 4);
+      stbtt__buf_skip(b, offsize * count);
+      stbtt__buf_skip(b, stbtt__buf_get(b, offsize) - 1);
+   }
+   return stbtt__buf_range(b, start, b->cursor - start);
+}
+
+static stbtt_uint32 stbtt__cff_int(stbtt__buf *b)
+{
+   int b0 = stbtt__buf_get8(b);
+   if (b0 >= 32 && b0 <= 246)       return b0 - 139;
+   else if (b0 >= 247 && b0 <= 250) return (b0 - 247)*256 + stbtt__buf_get8(b) + 108;
+   else if (b0 >= 251 && b0 <= 254) return -(b0 - 251)*256 - stbtt__buf_get8(b) - 108;
+   else if (b0 == 28)               return stbtt__buf_get16(b);
+   else if (b0 == 29)               return stbtt__buf_get32(b);
+   STBTT_assert(0);
+   return 0;
+}
+
+static void stbtt__cff_skip_operand(stbtt__buf *b) {
+   int v, b0 = stbtt__buf_peek8(b);
+   STBTT_assert(b0 >= 28);
+   if (b0 == 30) {
+      stbtt__buf_skip(b, 1);
+      while (b->cursor < b->size) {
+         v = stbtt__buf_get8(b);
+         if ((v & 0xF) == 0xF || (v >> 4) == 0xF)
+            break;
+      }
+   } else {
+      stbtt__cff_int(b);
+   }
+}
+
+static stbtt__buf stbtt__dict_get(stbtt__buf *b, int key)
+{
+   stbtt__buf_seek(b, 0);
+   while (b->cursor < b->size) {
+      int start = b->cursor, end, op;
+      while (stbtt__buf_peek8(b) >= 28)
+         stbtt__cff_skip_operand(b);
+      end = b->cursor;
+      op = stbtt__buf_get8(b);
+      if (op == 12)  op = stbtt__buf_get8(b) | 0x100;
+      if (op == key) return stbtt__buf_range(b, start, end-start);
+   }
+   return stbtt__buf_range(b, 0, 0);
+}
+
+static void stbtt__dict_get_ints(stbtt__buf *b, int key, int outcount, stbtt_uint32 *out)
+{
+   int i;
+   stbtt__buf operands = stbtt__dict_get(b, key);
+   for (i = 0; i < outcount && operands.cursor < operands.size; i++)
+      out[i] = stbtt__cff_int(&operands);
+}
+
+static int stbtt__cff_index_count(stbtt__buf *b)
+{
+   stbtt__buf_seek(b, 0);
+   return stbtt__buf_get16(b);
+}
+
+static stbtt__buf stbtt__cff_index_get(stbtt__buf b, int i)
+{
+   int count, offsize, start, end;
+   stbtt__buf_seek(&b, 0);
+   count = stbtt__buf_get16(&b);
+   offsize = stbtt__buf_get8(&b);
+   STBTT_assert(i >= 0 && i < count);
+   STBTT_assert(offsize >= 1 && offsize <= 4);
+   stbtt__buf_skip(&b, i*offsize);
+   start = stbtt__buf_get(&b, offsize);
+   end = stbtt__buf_get(&b, offsize);
+   return stbtt__buf_range(&b, 2+(count+1)*offsize+start, end - start);
+}
+
+//////////////////////////////////////////////////////////////////////////
+//
+// accessors to parse data from file
+//
+
+// on platforms that don't allow misaligned reads, if we want to allow
+// truetype fonts that aren't padded to alignment, define ALLOW_UNALIGNED_TRUETYPE
+
+#define ttBYTE(p)     (* (stbtt_uint8 *) (p))
+#define ttCHAR(p)     (* (stbtt_int8 *) (p))
+#define ttFixed(p)    ttLONG(p)
+
+static stbtt_uint16 ttUSHORT(stbtt_uint8 *p) { return p[0]*256 + p[1]; }
+static stbtt_int16 ttSHORT(stbtt_uint8 *p)   { return p[0]*256 + p[1]; }
+static stbtt_uint32 ttULONG(stbtt_uint8 *p)  { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; }
+static stbtt_int32 ttLONG(stbtt_uint8 *p)    { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; }
+
+#define stbtt_tag4(p,c0,c1,c2,c3) ((p)[0] == (c0) && (p)[1] == (c1) && (p)[2] == (c2) && (p)[3] == (c3))
+#define stbtt_tag(p,str)           stbtt_tag4(p,str[0],str[1],str[2],str[3])
+
+static int stbtt__isfont(stbtt_uint8 *font)
+{
+   // check the version number
+   if (stbtt_tag4(font, '1',0,0,0))  return 1; // TrueType 1
+   if (stbtt_tag(font, "typ1"))   return 1; // TrueType with type 1 font -- we don't support this!
+   if (stbtt_tag(font, "OTTO"))   return 1; // OpenType with CFF
+   if (stbtt_tag4(font, 0,1,0,0)) return 1; // OpenType 1.0
+   if (stbtt_tag(font, "true"))   return 1; // Apple specification for TrueType fonts
+   return 0;
+}
+
+// @OPTIMIZE: binary search
+static stbtt_uint32 stbtt__find_table(stbtt_uint8 *data, stbtt_uint32 fontstart, const char *tag)
+{
+   stbtt_int32 num_tables = ttUSHORT(data+fontstart+4);
+   stbtt_uint32 tabledir = fontstart + 12;
+   stbtt_int32 i;
+   for (i=0; i < num_tables; ++i) {
+      stbtt_uint32 loc = tabledir + 16*i;
+      if (stbtt_tag(data+loc+0, tag))
+         return ttULONG(data+loc+8);
+   }
+   return 0;
+}
+
+static int stbtt_GetFontOffsetForIndex_internal(unsigned char *font_collection, int index)
+{
+   // if it's just a font, there's only one valid index
+   if (stbtt__isfont(font_collection))
+      return index == 0 ? 0 : -1;
+
+   // check if it's a TTC
+   if (stbtt_tag(font_collection, "ttcf")) {
+      // version 1?
+      if (ttULONG(font_collection+4) == 0x00010000 || ttULONG(font_collection+4) == 0x00020000) {
+         stbtt_int32 n = ttLONG(font_collection+8);
+         if (index >= n)
+            return -1;
+         return ttULONG(font_collection+12+index*4);
+      }
+   }
+   return -1;
+}
+
+static int stbtt_GetNumberOfFonts_internal(unsigned char *font_collection)
+{
+   // if it's just a font, there's only one valid font
+   if (stbtt__isfont(font_collection))
+      return 1;
+
+   // check if it's a TTC
+   if (stbtt_tag(font_collection, "ttcf")) {
+      // version 1?
+      if (ttULONG(font_collection+4) == 0x00010000 || ttULONG(font_collection+4) == 0x00020000) {
+         return ttLONG(font_collection+8);
+      }
+   }
+   return 0;
+}
+
+static stbtt__buf stbtt__get_subrs(stbtt__buf cff, stbtt__buf fontdict)
+{
+   stbtt_uint32 subrsoff = 0, private_loc[2] = { 0, 0 };
+   stbtt__buf pdict;
+   stbtt__dict_get_ints(&fontdict, 18, 2, private_loc);
+   if (!private_loc[1] || !private_loc[0]) return stbtt__new_buf(NULL, 0);
+   pdict = stbtt__buf_range(&cff, private_loc[1], private_loc[0]);
+   stbtt__dict_get_ints(&pdict, 19, 1, &subrsoff);
+   if (!subrsoff) return stbtt__new_buf(NULL, 0);
+   stbtt__buf_seek(&cff, private_loc[1]+subrsoff);
+   return stbtt__cff_get_index(&cff);
+}
+
+// since most people won't use this, find this table the first time it's needed
+static int stbtt__get_svg(stbtt_fontinfo *info)
+{
+   stbtt_uint32 t;
+   if (info->svg < 0) {
+      t = stbtt__find_table(info->data, info->fontstart, "SVG ");
+      if (t) {
+         stbtt_uint32 offset = ttULONG(info->data + t + 2);
+         info->svg = t + offset;
+      } else {
+         info->svg = 0;
+      }
+   }
+   return info->svg;
+}
+
+static int stbtt_InitFont_internal(stbtt_fontinfo *info, unsigned char *data, int fontstart)
+{
+   stbtt_uint32 cmap, t;
+   stbtt_int32 i,numTables;
+
+   info->data = data;
+   info->fontstart = fontstart;
+   info->cff = stbtt__new_buf(NULL, 0);
+
+   cmap = stbtt__find_table(data, fontstart, "cmap");       // required
+   info->loca = stbtt__find_table(data, fontstart, "loca"); // required
+   info->head = stbtt__find_table(data, fontstart, "head"); // required
+   info->glyf = stbtt__find_table(data, fontstart, "glyf"); // required
+   info->hhea = stbtt__find_table(data, fontstart, "hhea"); // required
+   info->hmtx = stbtt__find_table(data, fontstart, "hmtx"); // required
+   info->kern = stbtt__find_table(data, fontstart, "kern"); // not required
+   info->gpos = stbtt__find_table(data, fontstart, "GPOS"); // not required
+
+   if (!cmap || !info->head || !info->hhea || !info->hmtx)
+      return 0;
+   if (info->glyf) {
+      // required for truetype
+      if (!info->loca) return 0;
+   } else {
+      // initialization for CFF / Type2 fonts (OTF)
+      stbtt__buf b, topdict, topdictidx;
+      stbtt_uint32 cstype = 2, charstrings = 0, fdarrayoff = 0, fdselectoff = 0;
+      stbtt_uint32 cff;
+
+      cff = stbtt__find_table(data, fontstart, "CFF ");
+      if (!cff) return 0;
+
+      info->fontdicts = stbtt__new_buf(NULL, 0);
+      info->fdselect = stbtt__new_buf(NULL, 0);
+
+      // @TODO this should use size from table (not 512MB)
+      info->cff = stbtt__new_buf(data+cff, 512*1024*1024);
+      b = info->cff;
+
+      // read the header
+      stbtt__buf_skip(&b, 2);
+      stbtt__buf_seek(&b, stbtt__buf_get8(&b)); // hdrsize
+
+      // @TODO the name INDEX could list multiple fonts,
+      // but we just use the first one.
+      stbtt__cff_get_index(&b);  // name INDEX
+      topdictidx = stbtt__cff_get_index(&b);
+      topdict = stbtt__cff_index_get(topdictidx, 0);
+      stbtt__cff_get_index(&b);  // string INDEX
+      info->gsubrs = stbtt__cff_get_index(&b);
+
+      stbtt__dict_get_ints(&topdict, 17, 1, &charstrings);
+      stbtt__dict_get_ints(&topdict, 0x100 | 6, 1, &cstype);
+      stbtt__dict_get_ints(&topdict, 0x100 | 36, 1, &fdarrayoff);
+      stbtt__dict_get_ints(&topdict, 0x100 | 37, 1, &fdselectoff);
+      info->subrs = stbtt__get_subrs(b, topdict);
+
+      // we only support Type 2 charstrings
+      if (cstype != 2) return 0;
+      if (charstrings == 0) return 0;
+
+      if (fdarrayoff) {
+         // looks like a CID font
+         if (!fdselectoff) return 0;
+         stbtt__buf_seek(&b, fdarrayoff);
+         info->fontdicts = stbtt__cff_get_index(&b);
+         info->fdselect = stbtt__buf_range(&b, fdselectoff, b.size-fdselectoff);
+      }
+
+      stbtt__buf_seek(&b, charstrings);
+      info->charstrings = stbtt__cff_get_index(&b);
+   }
+
+   t = stbtt__find_table(data, fontstart, "maxp");
+   if (t)
+      info->numGlyphs = ttUSHORT(data+t+4);
+   else
+      info->numGlyphs = 0xffff;
+
+   info->svg = -1;
+
+   // find a cmap encoding table we understand *now* to avoid searching
+   // later. (todo: could make this installable)
+   // the same regardless of glyph.
+   numTables = ttUSHORT(data + cmap + 2);
+   info->index_map = 0;
+   for (i=0; i < numTables; ++i) {
+      stbtt_uint32 encoding_record = cmap + 4 + 8 * i;
+      // find an encoding we understand:
+      switch(ttUSHORT(data+encoding_record)) {
+         case STBTT_PLATFORM_ID_MICROSOFT:
+            switch (ttUSHORT(data+encoding_record+2)) {
+               case STBTT_MS_EID_UNICODE_BMP:
+               case STBTT_MS_EID_UNICODE_FULL:
+                  // MS/Unicode
+                  info->index_map = cmap + ttULONG(data+encoding_record+4);
+                  break;
+            }
+            break;
+        case STBTT_PLATFORM_ID_UNICODE:
+            // Mac/iOS has these
+            // all the encodingIDs are unicode, so we don't bother to check it
+            info->index_map = cmap + ttULONG(data+encoding_record+4);
+            break;
+      }
+   }
+   if (info->index_map == 0)
+      return 0;
+
+   info->indexToLocFormat = ttUSHORT(data+info->head + 50);
+   return 1;
+}
+
+STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint)
+{
+   stbtt_uint8 *data = info->data;
+   stbtt_uint32 index_map = info->index_map;
+
+   stbtt_uint16 format = ttUSHORT(data + index_map + 0);
+   if (format == 0) { // apple byte encoding
+      stbtt_int32 bytes = ttUSHORT(data + index_map + 2);
+      if (unicode_codepoint < bytes-6)
+         return ttBYTE(data + index_map + 6 + unicode_codepoint);
+      return 0;
+   } else if (format == 6) {
+      stbtt_uint32 first = ttUSHORT(data + index_map + 6);
+      stbtt_uint32 count = ttUSHORT(data + index_map + 8);
+      if ((stbtt_uint32) unicode_codepoint >= first && (stbtt_uint32) unicode_codepoint < first+count)
+         return ttUSHORT(data + index_map + 10 + (unicode_codepoint - first)*2);
+      return 0;
+   } else if (format == 2) {
+      STBTT_assert(0); // @TODO: high-byte mapping for japanese/chinese/korean
+      return 0;
+   } else if (format == 4) { // standard mapping for windows fonts: binary search collection of ranges
+      stbtt_uint16 segcount = ttUSHORT(data+index_map+6) >> 1;
+      stbtt_uint16 searchRange = ttUSHORT(data+index_map+8) >> 1;
+      stbtt_uint16 entrySelector = ttUSHORT(data+index_map+10);
+      stbtt_uint16 rangeShift = ttUSHORT(data+index_map+12) >> 1;
+
+      // do a binary search of the segments
+      stbtt_uint32 endCount = index_map + 14;
+      stbtt_uint32 search = endCount;
+
+      if (unicode_codepoint > 0xffff)
+         return 0;
+
+      // they lie from endCount .. endCount + segCount
+      // but searchRange is the nearest power of two, so...
+      if (unicode_codepoint >= ttUSHORT(data + search + rangeShift*2))
+         search += rangeShift*2;
+
+      // now decrement to bias correctly to find smallest
+      search -= 2;
+      while (entrySelector) {
+         stbtt_uint16 end;
+         searchRange >>= 1;
+         end = ttUSHORT(data + search + searchRange*2);
+         if (unicode_codepoint > end)
+            search += searchRange*2;
+         --entrySelector;
+      }
+      search += 2;
+
+      {
+         stbtt_uint16 offset, start, last;
+         stbtt_uint16 item = (stbtt_uint16) ((search - endCount) >> 1);
+
+         start = ttUSHORT(data + index_map + 14 + segcount*2 + 2 + 2*item);
+         last = ttUSHORT(data + endCount + 2*item);
+         if (unicode_codepoint < start || unicode_codepoint > last)
+            return 0;
+
+         offset = ttUSHORT(data + index_map + 14 + segcount*6 + 2 + 2*item);
+         if (offset == 0)
+            return (stbtt_uint16) (unicode_codepoint + ttSHORT(data + index_map + 14 + segcount*4 + 2 + 2*item));
+
+         return ttUSHORT(data + offset + (unicode_codepoint-start)*2 + index_map + 14 + segcount*6 + 2 + 2*item);
+      }
+   } else if (format == 12 || format == 13) {
+      stbtt_uint32 ngroups = ttULONG(data+index_map+12);
+      stbtt_int32 low,high;
+      low = 0; high = (stbtt_int32)ngroups;
+      // Binary search the right group.
+      while (low < high) {
+         stbtt_int32 mid = low + ((high-low) >> 1); // rounds down, so low <= mid < high
+         stbtt_uint32 start_char = ttULONG(data+index_map+16+mid*12);
+         stbtt_uint32 end_char = ttULONG(data+index_map+16+mid*12+4);
+         if ((stbtt_uint32) unicode_codepoint < start_char)
+            high = mid;
+         else if ((stbtt_uint32) unicode_codepoint > end_char)
+            low = mid+1;
+         else {
+            stbtt_uint32 start_glyph = ttULONG(data+index_map+16+mid*12+8);
+            if (format == 12)
+               return start_glyph + unicode_codepoint-start_char;
+            else // format == 13
+               return start_glyph;
+         }
+      }
+      return 0; // not found
+   }
+   // @TODO
+   STBTT_assert(0);
+   return 0;
+}
+
+STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices)
+{
+   return stbtt_GetGlyphShape(info, stbtt_FindGlyphIndex(info, unicode_codepoint), vertices);
+}
+
+static void stbtt_setvertex(stbtt_vertex *v, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy)
+{
+   v->type = type;
+   v->x = (stbtt_int16) x;
+   v->y = (stbtt_int16) y;
+   v->cx = (stbtt_int16) cx;
+   v->cy = (stbtt_int16) cy;
+}
+
+static int stbtt__GetGlyfOffset(const stbtt_fontinfo *info, int glyph_index)
+{
+   int g1,g2;
+
+   STBTT_assert(!info->cff.size);
+
+   if (glyph_index >= info->numGlyphs) return -1; // glyph index out of range
+   if (info->indexToLocFormat >= 2)    return -1; // unknown index->glyph map format
+
+   if (info->indexToLocFormat == 0) {
+      g1 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2) * 2;
+      g2 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2 + 2) * 2;
+   } else {
+      g1 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4);
+      g2 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4 + 4);
+   }
+
+   return g1==g2 ? -1 : g1; // if length is 0, return -1
+}
+
+static int stbtt__GetGlyphInfoT2(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);
+
+STBTT_DEF int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1)
+{
+   if (info->cff.size) {
+      stbtt__GetGlyphInfoT2(info, glyph_index, x0, y0, x1, y1);
+   } else {
+      int g = stbtt__GetGlyfOffset(info, glyph_index);
+      if (g < 0) return 0;
+
+      if (x0) *x0 = ttSHORT(info->data + g + 2);
+      if (y0) *y0 = ttSHORT(info->data + g + 4);
+      if (x1) *x1 = ttSHORT(info->data + g + 6);
+      if (y1) *y1 = ttSHORT(info->data + g + 8);
+   }
+   return 1;
+}
+
+STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1)
+{
+   return stbtt_GetGlyphBox(info, stbtt_FindGlyphIndex(info,codepoint), x0,y0,x1,y1);
+}
+
+STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index)
+{
+   stbtt_int16 numberOfContours;
+   int g;
+   if (info->cff.size)
+      return stbtt__GetGlyphInfoT2(info, glyph_index, NULL, NULL, NULL, NULL) == 0;
+   g = stbtt__GetGlyfOffset(info, glyph_index);
+   if (g < 0) return 1;
+   numberOfContours = ttSHORT(info->data + g);
+   return numberOfContours == 0;
+}
+
+static int stbtt__close_shape(stbtt_vertex *vertices, int num_vertices, int was_off, int start_off,
+    stbtt_int32 sx, stbtt_int32 sy, stbtt_int32 scx, stbtt_int32 scy, stbtt_int32 cx, stbtt_int32 cy)
+{
+   if (start_off) {
+      if (was_off)
+         stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+scx)>>1, (cy+scy)>>1, cx,cy);
+      stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, sx,sy,scx,scy);
+   } else {
+      if (was_off)
+         stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve,sx,sy,cx,cy);
+      else
+         stbtt_setvertex(&vertices[num_vertices++], STBTT_vline,sx,sy,0,0);
+   }
+   return num_vertices;
+}
+
+static int stbtt__GetGlyphShapeTT(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
+{
+   stbtt_int16 numberOfContours;
+   stbtt_uint8 *endPtsOfContours;
+   stbtt_uint8 *data = info->data;
+   stbtt_vertex *vertices=0;
+   int num_vertices=0;
+   int g = stbtt__GetGlyfOffset(info, glyph_index);
+
+   *pvertices = NULL;
+
+   if (g < 0) return 0;
+
+   numberOfContours = ttSHORT(data + g);
+
+   if (numberOfContours > 0) {
+      stbtt_uint8 flags=0,flagcount;
+      stbtt_int32 ins, i,j=0,m,n, next_move, was_off=0, off, start_off=0;
+      stbtt_int32 x,y,cx,cy,sx,sy, scx,scy;
+      stbtt_uint8 *points;
+      endPtsOfContours = (data + g + 10);
+      ins = ttUSHORT(data + g + 10 + numberOfContours * 2);
+      points = data + g + 10 + numberOfContours * 2 + 2 + ins;
+
+      n = 1+ttUSHORT(endPtsOfContours + numberOfContours*2-2);
+
+      m = n + 2*numberOfContours;  // a loose bound on how many vertices we might need
+      vertices = (stbtt_vertex *) STBTT_malloc(m * sizeof(vertices[0]), info->userdata);
+      if (vertices == 0)
+         return 0;
+
+      next_move = 0;
+      flagcount=0;
+
+      // in first pass, we load uninterpreted data into the allocated array
+      // above, shifted to the end of the array so we won't overwrite it when
+      // we create our final data starting from the front
+
+      off = m - n; // starting offset for uninterpreted data, regardless of how m ends up being calculated
+
+      // first load flags
+
+      for (i=0; i < n; ++i) {
+         if (flagcount == 0) {
+            flags = *points++;
+            if (flags & 8)
+               flagcount = *points++;
+         } else
+            --flagcount;
+         vertices[off+i].type = flags;
+      }
+
+      // now load x coordinates
+      x=0;
+      for (i=0; i < n; ++i) {
+         flags = vertices[off+i].type;
+         if (flags & 2) {
+            stbtt_int16 dx = *points++;
+            x += (flags & 16) ? dx : -dx; // ???
+         } else {
+            if (!(flags & 16)) {
+               x = x + (stbtt_int16) (points[0]*256 + points[1]);
+               points += 2;
+            }
+         }
+         vertices[off+i].x = (stbtt_int16) x;
+      }
+
+      // now load y coordinates
+      y=0;
+      for (i=0; i < n; ++i) {
+         flags = vertices[off+i].type;
+         if (flags & 4) {
+            stbtt_int16 dy = *points++;
+            y += (flags & 32) ? dy : -dy; // ???
+         } else {
+            if (!(flags & 32)) {
+               y = y + (stbtt_int16) (points[0]*256 + points[1]);
+               points += 2;
+            }
+         }
+         vertices[off+i].y = (stbtt_int16) y;
+      }
+
+      // now convert them to our format
+      num_vertices=0;
+      sx = sy = cx = cy = scx = scy = 0;
+      for (i=0; i < n; ++i) {
+         flags = vertices[off+i].type;
+         x     = (stbtt_int16) vertices[off+i].x;
+         y     = (stbtt_int16) vertices[off+i].y;
+
+         if (next_move == i) {
+            if (i != 0)
+               num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy);
+
+            // now start the new one
+            start_off = !(flags & 1);
+            if (start_off) {
+               // if we start off with an off-curve point, then when we need to find a point on the curve
+               // where we can start, and we need to save some state for when we wraparound.
+               scx = x;
+               scy = y;
+               if (!(vertices[off+i+1].type & 1)) {
+                  // next point is also a curve point, so interpolate an on-point curve
+                  sx = (x + (stbtt_int32) vertices[off+i+1].x) >> 1;
+                  sy = (y + (stbtt_int32) vertices[off+i+1].y) >> 1;
+               } else {
+                  // otherwise just use the next point as our start point
+                  sx = (stbtt_int32) vertices[off+i+1].x;
+                  sy = (stbtt_int32) vertices[off+i+1].y;
+                  ++i; // we're using point i+1 as the starting point, so skip it
+               }
+            } else {
+               sx = x;
+               sy = y;
+            }
+            stbtt_setvertex(&vertices[num_vertices++], STBTT_vmove,sx,sy,0,0);
+            was_off = 0;
+            next_move = 1 + ttUSHORT(endPtsOfContours+j*2);
+            ++j;
+         } else {
+            if (!(flags & 1)) { // if it's a curve
+               if (was_off) // two off-curve control points in a row means interpolate an on-curve midpoint
+                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+x)>>1, (cy+y)>>1, cx, cy);
+               cx = x;
+               cy = y;
+               was_off = 1;
+            } else {
+               if (was_off)
+                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, x,y, cx, cy);
+               else
+                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vline, x,y,0,0);
+               was_off = 0;
+            }
+         }
+      }
+      num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy);
+   } else if (numberOfContours < 0) {
+      // Compound shapes.
+      int more = 1;
+      stbtt_uint8 *comp = data + g + 10;
+      num_vertices = 0;
+      vertices = 0;
+      while (more) {
+         stbtt_uint16 flags, gidx;
+         int comp_num_verts = 0, i;
+         stbtt_vertex *comp_verts = 0, *tmp = 0;
+         float mtx[6] = {1,0,0,1,0,0}, m, n;
+
+         flags = ttSHORT(comp); comp+=2;
+         gidx = ttSHORT(comp); comp+=2;
+
+         if (flags & 2) { // XY values
+            if (flags & 1) { // shorts
+               mtx[4] = ttSHORT(comp); comp+=2;
+               mtx[5] = ttSHORT(comp); comp+=2;
+            } else {
+               mtx[4] = ttCHAR(comp); comp+=1;
+               mtx[5] = ttCHAR(comp); comp+=1;
+            }
+         }
+         else {
+            // @TODO handle matching point
+            STBTT_assert(0);
+         }
+         if (flags & (1<<3)) { // WE_HAVE_A_SCALE
+            mtx[0] = mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[1] = mtx[2] = 0;
+         } else if (flags & (1<<6)) { // WE_HAVE_AN_X_AND_YSCALE
+            mtx[0] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[1] = mtx[2] = 0;
+            mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
+         } else if (flags & (1<<7)) { // WE_HAVE_A_TWO_BY_TWO
+            mtx[0] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[1] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[2] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
+         }
+
+         // Find transformation scales.
+         m = (float) STBTT_sqrt(mtx[0]*mtx[0] + mtx[1]*mtx[1]);
+         n = (float) STBTT_sqrt(mtx[2]*mtx[2] + mtx[3]*mtx[3]);
+
+         // Get indexed glyph.
+         comp_num_verts = stbtt_GetGlyphShape(info, gidx, &comp_verts);
+         if (comp_num_verts > 0) {
+            // Transform vertices.
+            for (i = 0; i < comp_num_verts; ++i) {
+               stbtt_vertex* v = &comp_verts[i];
+               stbtt_vertex_type x,y;
+               x=v->x; y=v->y;
+               v->x = (stbtt_vertex_type)(m * (mtx[0]*x + mtx[2]*y + mtx[4]));
+               v->y = (stbtt_vertex_type)(n * (mtx[1]*x + mtx[3]*y + mtx[5]));
+               x=v->cx; y=v->cy;
+               v->cx = (stbtt_vertex_type)(m * (mtx[0]*x + mtx[2]*y + mtx[4]));
+               v->cy = (stbtt_vertex_type)(n * (mtx[1]*x + mtx[3]*y + mtx[5]));
+            }
+            // Append vertices.
+            tmp = (stbtt_vertex*)STBTT_malloc((num_vertices+comp_num_verts)*sizeof(stbtt_vertex), info->userdata);
+            if (!tmp) {
+               if (vertices) STBTT_free(vertices, info->userdata);
+               if (comp_verts) STBTT_free(comp_verts, info->userdata);
+               return 0;
+            }
+            if (num_vertices > 0 && vertices) STBTT_memcpy(tmp, vertices, num_vertices*sizeof(stbtt_vertex));
+            STBTT_memcpy(tmp+num_vertices, comp_verts, comp_num_verts*sizeof(stbtt_vertex));
+            if (vertices) STBTT_free(vertices, info->userdata);
+            vertices = tmp;
+            STBTT_free(comp_verts, info->userdata);
+            num_vertices += comp_num_verts;
+         }
+         // More components ?
+         more = flags & (1<<5);
+      }
+   } else {
+      // numberOfCounters == 0, do nothing
+   }
+
+   *pvertices = vertices;
+   return num_vertices;
+}
+
+typedef struct
+{
+   int bounds;
+   int started;
+   float first_x, first_y;
+   float x, y;
+   stbtt_int32 min_x, max_x, min_y, max_y;
+
+   stbtt_vertex *pvertices;
+   int num_vertices;
+} stbtt__csctx;
+
+#define STBTT__CSCTX_INIT(bounds) {bounds,0, 0,0, 0,0, 0,0,0,0, NULL, 0}
+
+static void stbtt__track_vertex(stbtt__csctx *c, stbtt_int32 x, stbtt_int32 y)
+{
+   if (x > c->max_x || !c->started) c->max_x = x;
+   if (y > c->max_y || !c->started) c->max_y = y;
+   if (x < c->min_x || !c->started) c->min_x = x;
+   if (y < c->min_y || !c->started) c->min_y = y;
+   c->started = 1;
+}
+
+static void stbtt__csctx_v(stbtt__csctx *c, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy, stbtt_int32 cx1, stbtt_int32 cy1)
+{
+   if (c->bounds) {
+      stbtt__track_vertex(c, x, y);
+      if (type == STBTT_vcubic) {
+         stbtt__track_vertex(c, cx, cy);
+         stbtt__track_vertex(c, cx1, cy1);
+      }
+   } else {
+      stbtt_setvertex(&c->pvertices[c->num_vertices], type, x, y, cx, cy);
+      c->pvertices[c->num_vertices].cx1 = (stbtt_int16) cx1;
+      c->pvertices[c->num_vertices].cy1 = (stbtt_int16) cy1;
+   }
+   c->num_vertices++;
+}
+
+static void stbtt__csctx_close_shape(stbtt__csctx *ctx)
+{
+   if (ctx->first_x != ctx->x || ctx->first_y != ctx->y)
+      stbtt__csctx_v(ctx, STBTT_vline, (int)ctx->first_x, (int)ctx->first_y, 0, 0, 0, 0);
+}
+
+static void stbtt__csctx_rmove_to(stbtt__csctx *ctx, float dx, float dy)
+{
+   stbtt__csctx_close_shape(ctx);
+   ctx->first_x = ctx->x = ctx->x + dx;
+   ctx->first_y = ctx->y = ctx->y + dy;
+   stbtt__csctx_v(ctx, STBTT_vmove, (int)ctx->x, (int)ctx->y, 0, 0, 0, 0);
+}
+
+static void stbtt__csctx_rline_to(stbtt__csctx *ctx, float dx, float dy)
+{
+   ctx->x += dx;
+   ctx->y += dy;
+   stbtt__csctx_v(ctx, STBTT_vline, (int)ctx->x, (int)ctx->y, 0, 0, 0, 0);
+}
+
+static void stbtt__csctx_rccurve_to(stbtt__csctx *ctx, float dx1, float dy1, float dx2, float dy2, float dx3, float dy3)
+{
+   float cx1 = ctx->x + dx1;
+   float cy1 = ctx->y + dy1;
+   float cx2 = cx1 + dx2;
+   float cy2 = cy1 + dy2;
+   ctx->x = cx2 + dx3;
+   ctx->y = cy2 + dy3;
+   stbtt__csctx_v(ctx, STBTT_vcubic, (int)ctx->x, (int)ctx->y, (int)cx1, (int)cy1, (int)cx2, (int)cy2);
+}
+
+static stbtt__buf stbtt__get_subr(stbtt__buf idx, int n)
+{
+   int count = stbtt__cff_index_count(&idx);
+   int bias = 107;
+   if (count >= 33900)
+      bias = 32768;
+   else if (count >= 1240)
+      bias = 1131;
+   n += bias;
+   if (n < 0 || n >= count)
+      return stbtt__new_buf(NULL, 0);
+   return stbtt__cff_index_get(idx, n);
+}
+
+static stbtt__buf stbtt__cid_get_glyph_subrs(const stbtt_fontinfo *info, int glyph_index)
+{
+   stbtt__buf fdselect = info->fdselect;
+   int nranges, start, end, v, fmt, fdselector = -1, i;
+
+   stbtt__buf_seek(&fdselect, 0);
+   fmt = stbtt__buf_get8(&fdselect);
+   if (fmt == 0) {
+      // untested
+      stbtt__buf_skip(&fdselect, glyph_index);
+      fdselector = stbtt__buf_get8(&fdselect);
+   } else if (fmt == 3) {
+      nranges = stbtt__buf_get16(&fdselect);
+      start = stbtt__buf_get16(&fdselect);
+      for (i = 0; i < nranges; i++) {
+         v = stbtt__buf_get8(&fdselect);
+         end = stbtt__buf_get16(&fdselect);
+         if (glyph_index >= start && glyph_index < end) {
+            fdselector = v;
+            break;
+         }
+         start = end;
+      }
+   }
+   if (fdselector == -1) stbtt__new_buf(NULL, 0);
+   return stbtt__get_subrs(info->cff, stbtt__cff_index_get(info->fontdicts, fdselector));
+}
+
+static int stbtt__run_charstring(const stbtt_fontinfo *info, int glyph_index, stbtt__csctx *c)
+{
+   int in_header = 1, maskbits = 0, subr_stack_height = 0, sp = 0, v, i, b0;
+   int has_subrs = 0, clear_stack;
+   float s[48];
+   stbtt__buf subr_stack[10], subrs = info->subrs, b;
+   float f;
+
+#define STBTT__CSERR(s) (0)
+
+   // this currently ignores the initial width value, which isn't needed if we have hmtx
+   b = stbtt__cff_index_get(info->charstrings, glyph_index);
+   while (b.cursor < b.size) {
+      i = 0;
+      clear_stack = 1;
+      b0 = stbtt__buf_get8(&b);
+      switch (b0) {
+      // @TODO implement hinting
+      case 0x13: // hintmask
+      case 0x14: // cntrmask
+         if (in_header)
+            maskbits += (sp / 2); // implicit "vstem"
+         in_header = 0;
+         stbtt__buf_skip(&b, (maskbits + 7) / 8);
+         break;
+
+      case 0x01: // hstem
+      case 0x03: // vstem
+      case 0x12: // hstemhm
+      case 0x17: // vstemhm
+         maskbits += (sp / 2);
+         break;
+
+      case 0x15: // rmoveto
+         in_header = 0;
+         if (sp < 2) return STBTT__CSERR("rmoveto stack");
+         stbtt__csctx_rmove_to(c, s[sp-2], s[sp-1]);
+         break;
+      case 0x04: // vmoveto
+         in_header = 0;
+         if (sp < 1) return STBTT__CSERR("vmoveto stack");
+         stbtt__csctx_rmove_to(c, 0, s[sp-1]);
+         break;
+      case 0x16: // hmoveto
+         in_header = 0;
+         if (sp < 1) return STBTT__CSERR("hmoveto stack");
+         stbtt__csctx_rmove_to(c, s[sp-1], 0);
+         break;
+
+      case 0x05: // rlineto
+         if (sp < 2) return STBTT__CSERR("rlineto stack");
+         for (; i + 1 < sp; i += 2)
+            stbtt__csctx_rline_to(c, s[i], s[i+1]);
+         break;
+
+      // hlineto/vlineto and vhcurveto/hvcurveto alternate horizontal and vertical
+      // starting from a different place.
+
+      case 0x07: // vlineto
+         if (sp < 1) return STBTT__CSERR("vlineto stack");
+         goto vlineto;
+      case 0x06: // hlineto
+         if (sp < 1) return STBTT__CSERR("hlineto stack");
+         for (;;) {
+            if (i >= sp) break;
+            stbtt__csctx_rline_to(c, s[i], 0);
+            i++;
+      vlineto:
+            if (i >= sp) break;
+            stbtt__csctx_rline_to(c, 0, s[i]);
+            i++;
+         }
+         break;
+
+      case 0x1F: // hvcurveto
+         if (sp < 4) return STBTT__CSERR("hvcurveto stack");
+         goto hvcurveto;
+      case 0x1E: // vhcurveto
+         if (sp < 4) return STBTT__CSERR("vhcurveto stack");
+         for (;;) {
+            if (i + 3 >= sp) break;
+            stbtt__csctx_rccurve_to(c, 0, s[i], s[i+1], s[i+2], s[i+3], (sp - i == 5) ? s[i + 4] : 0.0f);
+            i += 4;
+      hvcurveto:
+            if (i + 3 >= sp) break;
+            stbtt__csctx_rccurve_to(c, s[i], 0, s[i+1], s[i+2], (sp - i == 5) ? s[i+4] : 0.0f, s[i+3]);
+            i += 4;
+         }
+         break;
+
+      case 0x08: // rrcurveto
+         if (sp < 6) return STBTT__CSERR("rcurveline stack");
+         for (; i + 5 < sp; i += 6)
+            stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]);
+         break;
+
+      case 0x18: // rcurveline
+         if (sp < 8) return STBTT__CSERR("rcurveline stack");
+         for (; i + 5 < sp - 2; i += 6)
+            stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]);
+         if (i + 1 >= sp) return STBTT__CSERR("rcurveline stack");
+         stbtt__csctx_rline_to(c, s[i], s[i+1]);
+         break;
+
+      case 0x19: // rlinecurve
+         if (sp < 8) return STBTT__CSERR("rlinecurve stack");
+         for (; i + 1 < sp - 6; i += 2)
+            stbtt__csctx_rline_to(c, s[i], s[i+1]);
+         if (i + 5 >= sp) return STBTT__CSERR("rlinecurve stack");
+         stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]);
+         break;
+
+      case 0x1A: // vvcurveto
+      case 0x1B: // hhcurveto
+         if (sp < 4) return STBTT__CSERR("(vv|hh)curveto stack");
+         f = 0.0;
+         if (sp & 1) { f = s[i]; i++; }
+         for (; i + 3 < sp; i += 4) {
+            if (b0 == 0x1B)
+               stbtt__csctx_rccurve_to(c, s[i], f, s[i+1], s[i+2], s[i+3], 0.0);
+            else
+               stbtt__csctx_rccurve_to(c, f, s[i], s[i+1], s[i+2], 0.0, s[i+3]);
+            f = 0.0;
+         }
+         break;
+
+      case 0x0A: // callsubr
+         if (!has_subrs) {
+            if (info->fdselect.size)
+               subrs = stbtt__cid_get_glyph_subrs(info, glyph_index);
+            has_subrs = 1;
+         }
+         // FALLTHROUGH
+      case 0x1D: // callgsubr
+         if (sp < 1) return STBTT__CSERR("call(g|)subr stack");
+         v = (int) s[--sp];
+         if (subr_stack_height >= 10) return STBTT__CSERR("recursion limit");
+         subr_stack[subr_stack_height++] = b;
+         b = stbtt__get_subr(b0 == 0x0A ? subrs : info->gsubrs, v);
+         if (b.size == 0) return STBTT__CSERR("subr not found");
+         b.cursor = 0;
+         clear_stack = 0;
+         break;
+
+      case 0x0B: // return
+         if (subr_stack_height <= 0) return STBTT__CSERR("return outside subr");
+         b = subr_stack[--subr_stack_height];
+         clear_stack = 0;
+         break;
+
+      case 0x0E: // endchar
+         stbtt__csctx_close_shape(c);
+         return 1;
+
+      case 0x0C: { // two-byte escape
+         float dx1, dx2, dx3, dx4, dx5, dx6, dy1, dy2, dy3, dy4, dy5, dy6;
+         float dx, dy;
+         int b1 = stbtt__buf_get8(&b);
+         switch (b1) {
+         // @TODO These "flex" implementations ignore the flex-depth and resolution,
+         // and always draw beziers.
+         case 0x22: // hflex
+            if (sp < 7) return STBTT__CSERR("hflex stack");
+            dx1 = s[0];
+            dx2 = s[1];
+            dy2 = s[2];
+            dx3 = s[3];
+            dx4 = s[4];
+            dx5 = s[5];
+            dx6 = s[6];
+            stbtt__csctx_rccurve_to(c, dx1, 0, dx2, dy2, dx3, 0);
+            stbtt__csctx_rccurve_to(c, dx4, 0, dx5, -dy2, dx6, 0);
+            break;
+
+         case 0x23: // flex
+            if (sp < 13) return STBTT__CSERR("flex stack");
+            dx1 = s[0];
+            dy1 = s[1];
+            dx2 = s[2];
+            dy2 = s[3];
+            dx3 = s[4];
+            dy3 = s[5];
+            dx4 = s[6];
+            dy4 = s[7];
+            dx5 = s[8];
+            dy5 = s[9];
+            dx6 = s[10];
+            dy6 = s[11];
+            //fd is s[12]
+            stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, dy3);
+            stbtt__csctx_rccurve_to(c, dx4, dy4, dx5, dy5, dx6, dy6);
+            break;
+
+         case 0x24: // hflex1
+            if (sp < 9) return STBTT__CSERR("hflex1 stack");
+            dx1 = s[0];
+            dy1 = s[1];
+            dx2 = s[2];
+            dy2 = s[3];
+            dx3 = s[4];
+            dx4 = s[5];
+            dx5 = s[6];
+            dy5 = s[7];
+            dx6 = s[8];
+            stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, 0);
+            stbtt__csctx_rccurve_to(c, dx4, 0, dx5, dy5, dx6, -(dy1+dy2+dy5));
+            break;
+
+         case 0x25: // flex1
+            if (sp < 11) return STBTT__CSERR("flex1 stack");
+            dx1 = s[0];
+            dy1 = s[1];
+            dx2 = s[2];
+            dy2 = s[3];
+            dx3 = s[4];
+            dy3 = s[5];
+            dx4 = s[6];
+            dy4 = s[7];
+            dx5 = s[8];
+            dy5 = s[9];
+            dx6 = dy6 = s[10];
+            dx = dx1+dx2+dx3+dx4+dx5;
+            dy = dy1+dy2+dy3+dy4+dy5;
+            if (STBTT_fabs(dx) > STBTT_fabs(dy))
+               dy6 = -dy;
+            else
+               dx6 = -dx;
+            stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, dy3);
+            stbtt__csctx_rccurve_to(c, dx4, dy4, dx5, dy5, dx6, dy6);
+            break;
+
+         default:
+            return STBTT__CSERR("unimplemented");
+         }
+      } break;
+
+      default:
+         if (b0 != 255 && b0 != 28 && b0 < 32)
+            return STBTT__CSERR("reserved operator");
+
+         // push immediate
+         if (b0 == 255) {
+            f = (float)(stbtt_int32)stbtt__buf_get32(&b) / 0x10000;
+         } else {
+            stbtt__buf_skip(&b, -1);
+            f = (float)(stbtt_int16)stbtt__cff_int(&b);
+         }
+         if (sp >= 48) return STBTT__CSERR("push stack overflow");
+         s[sp++] = f;
+         clear_stack = 0;
+         break;
+      }
+      if (clear_stack) sp = 0;
+   }
+   return STBTT__CSERR("no endchar");
+
+#undef STBTT__CSERR
+}
+
+static int stbtt__GetGlyphShapeT2(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
+{
+   // runs the charstring twice, once to count and once to output (to avoid realloc)
+   stbtt__csctx count_ctx = STBTT__CSCTX_INIT(1);
+   stbtt__csctx output_ctx = STBTT__CSCTX_INIT(0);
+   if (stbtt__run_charstring(info, glyph_index, &count_ctx)) {
+      *pvertices = (stbtt_vertex*)STBTT_malloc(count_ctx.num_vertices*sizeof(stbtt_vertex), info->userdata);
+      output_ctx.pvertices = *pvertices;
+      if (stbtt__run_charstring(info, glyph_index, &output_ctx)) {
+         STBTT_assert(output_ctx.num_vertices == count_ctx.num_vertices);
+         return output_ctx.num_vertices;
+      }
+   }
+   *pvertices = NULL;
+   return 0;
+}
+
+static int stbtt__GetGlyphInfoT2(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1)
+{
+   stbtt__csctx c = STBTT__CSCTX_INIT(1);
+   int r = stbtt__run_charstring(info, glyph_index, &c);
+   if (x0)  *x0 = r ? c.min_x : 0;
+   if (y0)  *y0 = r ? c.min_y : 0;
+   if (x1)  *x1 = r ? c.max_x : 0;
+   if (y1)  *y1 = r ? c.max_y : 0;
+   return r ? c.num_vertices : 0;
+}
+
+STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
+{
+   if (!info->cff.size)
+      return stbtt__GetGlyphShapeTT(info, glyph_index, pvertices);
+   else
+      return stbtt__GetGlyphShapeT2(info, glyph_index, pvertices);
+}
+
+STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing)
+{
+   stbtt_uint16 numOfLongHorMetrics = ttUSHORT(info->data+info->hhea + 34);
+   if (glyph_index < numOfLongHorMetrics) {
+      if (advanceWidth)     *advanceWidth    = ttSHORT(info->data + info->hmtx + 4*glyph_index);
+      if (leftSideBearing)  *leftSideBearing = ttSHORT(info->data + info->hmtx + 4*glyph_index + 2);
+   } else {
+      if (advanceWidth)     *advanceWidth    = ttSHORT(info->data + info->hmtx + 4*(numOfLongHorMetrics-1));
+      if (leftSideBearing)  *leftSideBearing = ttSHORT(info->data + info->hmtx + 4*numOfLongHorMetrics + 2*(glyph_index - numOfLongHorMetrics));
+   }
+}
+
+STBTT_DEF int  stbtt_GetKerningTableLength(const stbtt_fontinfo *info)
+{
+   stbtt_uint8 *data = info->data + info->kern;
+
+   // we only look at the first table. it must be 'horizontal' and format 0.
+   if (!info->kern)
+      return 0;
+   if (ttUSHORT(data+2) < 1) // number of tables, need at least 1
+      return 0;
+   if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format
+      return 0;
+
+   return ttUSHORT(data+10);
+}
+
+STBTT_DEF int stbtt_GetKerningTable(const stbtt_fontinfo *info, stbtt_kerningentry* table, int table_length)
+{
+   stbtt_uint8 *data = info->data + info->kern;
+   int k, length;
+
+   // we only look at the first table. it must be 'horizontal' and format 0.
+   if (!info->kern)
+      return 0;
+   if (ttUSHORT(data+2) < 1) // number of tables, need at least 1
+      return 0;
+   if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format
+      return 0;
+
+   length = ttUSHORT(data+10);
+   if (table_length < length)
+      length = table_length;
+
+   for (k = 0; k < length; k++)
+   {
+      table[k].glyph1 = ttUSHORT(data+18+(k*6));
+      table[k].glyph2 = ttUSHORT(data+20+(k*6));
+      table[k].advance = ttSHORT(data+22+(k*6));
+   }
+
+   return length;
+}
+
+static int stbtt__GetGlyphKernInfoAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2)
+{
+   stbtt_uint8 *data = info->data + info->kern;
+   stbtt_uint32 needle, straw;
+   int l, r, m;
+
+   // we only look at the first table. it must be 'horizontal' and format 0.
+   if (!info->kern)
+      return 0;
+   if (ttUSHORT(data+2) < 1) // number of tables, need at least 1
+      return 0;
+   if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format
+      return 0;
+
+   l = 0;
+   r = ttUSHORT(data+10) - 1;
+   needle = glyph1 << 16 | glyph2;
+   while (l <= r) {
+      m = (l + r) >> 1;
+      straw = ttULONG(data+18+(m*6)); // note: unaligned read
+      if (needle < straw)
+         r = m - 1;
+      else if (needle > straw)
+         l = m + 1;
+      else
+         return ttSHORT(data+22+(m*6));
+   }
+   return 0;
+}
+
+static stbtt_int32 stbtt__GetCoverageIndex(stbtt_uint8 *coverageTable, int glyph)
+{
+   stbtt_uint16 coverageFormat = ttUSHORT(coverageTable);
+   switch (coverageFormat) {
+      case 1: {
+         stbtt_uint16 glyphCount = ttUSHORT(coverageTable + 2);
+
+         // Binary search.
+         stbtt_int32 l=0, r=glyphCount-1, m;
+         int straw, needle=glyph;
+         while (l <= r) {
+            stbtt_uint8 *glyphArray = coverageTable + 4;
+            stbtt_uint16 glyphID;
+            m = (l + r) >> 1;
+            glyphID = ttUSHORT(glyphArray + 2 * m);
+            straw = glyphID;
+            if (needle < straw)
+               r = m - 1;
+            else if (needle > straw)
+               l = m + 1;
+            else {
+               return m;
+            }
+         }
+         break;
+      }
+
+      case 2: {
+         stbtt_uint16 rangeCount = ttUSHORT(coverageTable + 2);
+         stbtt_uint8 *rangeArray = coverageTable + 4;
+
+         // Binary search.
+         stbtt_int32 l=0, r=rangeCount-1, m;
+         int strawStart, strawEnd, needle=glyph;
+         while (l <= r) {
+            stbtt_uint8 *rangeRecord;
+            m = (l + r) >> 1;
+            rangeRecord = rangeArray + 6 * m;
+            strawStart = ttUSHORT(rangeRecord);
+            strawEnd = ttUSHORT(rangeRecord + 2);
+            if (needle < strawStart)
+               r = m - 1;
+            else if (needle > strawEnd)
+               l = m + 1;
+            else {
+               stbtt_uint16 startCoverageIndex = ttUSHORT(rangeRecord + 4);
+               return startCoverageIndex + glyph - strawStart;
+            }
+         }
+         break;
+      }
+
+      default: return -1; // unsupported
+   }
+
+   return -1;
+}
+
+static stbtt_int32  stbtt__GetGlyphClass(stbtt_uint8 *classDefTable, int glyph)
+{
+   stbtt_uint16 classDefFormat = ttUSHORT(classDefTable);
+   switch (classDefFormat)
+   {
+      case 1: {
+         stbtt_uint16 startGlyphID = ttUSHORT(classDefTable + 2);
+         stbtt_uint16 glyphCount = ttUSHORT(classDefTable + 4);
+         stbtt_uint8 *classDef1ValueArray = classDefTable + 6;
+
+         if (glyph >= startGlyphID && glyph < startGlyphID + glyphCount)
+            return (stbtt_int32)ttUSHORT(classDef1ValueArray + 2 * (glyph - startGlyphID));
+         break;
+      }
+
+      case 2: {
+         stbtt_uint16 classRangeCount = ttUSHORT(classDefTable + 2);
+         stbtt_uint8 *classRangeRecords = classDefTable + 4;
+
+         // Binary search.
+         stbtt_int32 l=0, r=classRangeCount-1, m;
+         int strawStart, strawEnd, needle=glyph;
+         while (l <= r) {
+            stbtt_uint8 *classRangeRecord;
+            m = (l + r) >> 1;
+            classRangeRecord = classRangeRecords + 6 * m;
+            strawStart = ttUSHORT(classRangeRecord);
+            strawEnd = ttUSHORT(classRangeRecord + 2);
+            if (needle < strawStart)
+               r = m - 1;
+            else if (needle > strawEnd)
+               l = m + 1;
+            else
+               return (stbtt_int32)ttUSHORT(classRangeRecord + 4);
+         }
+         break;
+      }
+
+      default:
+         return -1; // Unsupported definition type, return an error.
+   }
+
+   // "All glyphs not assigned to a class fall into class 0". (OpenType spec)
+   return 0;
+}
+
+// Define to STBTT_assert(x) if you want to break on unimplemented formats.
+#define STBTT_GPOS_TODO_assert(x)
+
+static stbtt_int32 stbtt__GetGlyphGPOSInfoAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2)
+{
+   stbtt_uint16 lookupListOffset;
+   stbtt_uint8 *lookupList;
+   stbtt_uint16 lookupCount;
+   stbtt_uint8 *data;
+   stbtt_int32 i, sti;
+
+   if (!info->gpos) return 0;
+
+   data = info->data + info->gpos;
+
+   if (ttUSHORT(data+0) != 1) return 0; // Major version 1
+   if (ttUSHORT(data+2) != 0) return 0; // Minor version 0
+
+   lookupListOffset = ttUSHORT(data+8);
+   lookupList = data + lookupListOffset;
+   lookupCount = ttUSHORT(lookupList);
+
+   for (i=0; i<lookupCount; ++i) {
+      stbtt_uint16 lookupOffset = ttUSHORT(lookupList + 2 + 2 * i);
+      stbtt_uint8 *lookupTable = lookupList + lookupOffset;
+
+      stbtt_uint16 lookupType = ttUSHORT(lookupTable);
+      stbtt_uint16 subTableCount = ttUSHORT(lookupTable + 4);
+      stbtt_uint8 *subTableOffsets = lookupTable + 6;
+      if (lookupType != 2) // Pair Adjustment Positioning Subtable
+         continue;
+
+      for (sti=0; sti<subTableCount; sti++) {
+         stbtt_uint16 subtableOffset = ttUSHORT(subTableOffsets + 2 * sti);
+         stbtt_uint8 *table = lookupTable + subtableOffset;
+         stbtt_uint16 posFormat = ttUSHORT(table);
+         stbtt_uint16 coverageOffset = ttUSHORT(table + 2);
+         stbtt_int32 coverageIndex = stbtt__GetCoverageIndex(table + coverageOffset, glyph1);
+         if (coverageIndex == -1) continue;
+
+         switch (posFormat) {
+            case 1: {
+               stbtt_int32 l, r, m;
+               int straw, needle;
+               stbtt_uint16 valueFormat1 = ttUSHORT(table + 4);
+               stbtt_uint16 valueFormat2 = ttUSHORT(table + 6);
+               if (valueFormat1 == 4 && valueFormat2 == 0) { // Support more formats?
+                  stbtt_int32 valueRecordPairSizeInBytes = 2;
+                  stbtt_uint16 pairSetCount = ttUSHORT(table + 8);
+                  stbtt_uint16 pairPosOffset = ttUSHORT(table + 10 + 2 * coverageIndex);
+                  stbtt_uint8 *pairValueTable = table + pairPosOffset;
+                  stbtt_uint16 pairValueCount = ttUSHORT(pairValueTable);
+                  stbtt_uint8 *pairValueArray = pairValueTable + 2;
+
+                  if (coverageIndex >= pairSetCount) return 0;
+
+                  needle=glyph2;
+                  r=pairValueCount-1;
+                  l=0;
+
+                  // Binary search.
+                  while (l <= r) {
+                     stbtt_uint16 secondGlyph;
+                     stbtt_uint8 *pairValue;
+                     m = (l + r) >> 1;
+                     pairValue = pairValueArray + (2 + valueRecordPairSizeInBytes) * m;
+                     secondGlyph = ttUSHORT(pairValue);
+                     straw = secondGlyph;
+                     if (needle < straw)
+                        r = m - 1;
+                     else if (needle > straw)
+                        l = m + 1;
+                     else {
+                        stbtt_int16 xAdvance = ttSHORT(pairValue + 2);
+                        return xAdvance;
+                     }
+                  }
+               } else
+                  return 0;
+               break;
+            }
+
+            case 2: {
+               stbtt_uint16 valueFormat1 = ttUSHORT(table + 4);
+               stbtt_uint16 valueFormat2 = ttUSHORT(table + 6);
+               if (valueFormat1 == 4 && valueFormat2 == 0) { // Support more formats?
+                  stbtt_uint16 classDef1Offset = ttUSHORT(table + 8);
+                  stbtt_uint16 classDef2Offset = ttUSHORT(table + 10);
+                  int glyph1class = stbtt__GetGlyphClass(table + classDef1Offset, glyph1);
+                  int glyph2class = stbtt__GetGlyphClass(table + classDef2Offset, glyph2);
+
+                  stbtt_uint16 class1Count = ttUSHORT(table + 12);
+                  stbtt_uint16 class2Count = ttUSHORT(table + 14);
+                  stbtt_uint8 *class1Records, *class2Records;
+                  stbtt_int16 xAdvance;
+
+                  if (glyph1class < 0 || glyph1class >= class1Count) return 0; // malformed
+                  if (glyph2class < 0 || glyph2class >= class2Count) return 0; // malformed
+
+                  class1Records = table + 16;
+                  class2Records = class1Records + 2 * (glyph1class * class2Count);
+                  xAdvance = ttSHORT(class2Records + 2 * glyph2class);
+                  return xAdvance;
+               } else
+                  return 0;
+               break;
+            }
+
+            default:
+               return 0; // Unsupported position format
+         }
+      }
+   }
+
+   return 0;
+}
+
+STBTT_DEF int  stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int g1, int g2)
+{
+   int xAdvance = 0;
+
+   if (info->gpos)
+      xAdvance += stbtt__GetGlyphGPOSInfoAdvance(info, g1, g2);
+   else if (info->kern)
+      xAdvance += stbtt__GetGlyphKernInfoAdvance(info, g1, g2);
+
+   return xAdvance;
+}
+
+STBTT_DEF int  stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2)
+{
+   if (!info->kern && !info->gpos) // if no kerning table, don't waste time looking up both codepoint->glyphs
+      return 0;
+   return stbtt_GetGlyphKernAdvance(info, stbtt_FindGlyphIndex(info,ch1), stbtt_FindGlyphIndex(info,ch2));
+}
+
+STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing)
+{
+   stbtt_GetGlyphHMetrics(info, stbtt_FindGlyphIndex(info,codepoint), advanceWidth, leftSideBearing);
+}
+
+STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap)
+{
+   if (ascent ) *ascent  = ttSHORT(info->data+info->hhea + 4);
+   if (descent) *descent = ttSHORT(info->data+info->hhea + 6);
+   if (lineGap) *lineGap = ttSHORT(info->data+info->hhea + 8);
+}
+
+STBTT_DEF int  stbtt_GetFontVMetricsOS2(const stbtt_fontinfo *info, int *typoAscent, int *typoDescent, int *typoLineGap)
+{
+   int tab = stbtt__find_table(info->data, info->fontstart, "OS/2");
+   if (!tab)
+      return 0;
+   if (typoAscent ) *typoAscent  = ttSHORT(info->data+tab + 68);
+   if (typoDescent) *typoDescent = ttSHORT(info->data+tab + 70);
+   if (typoLineGap) *typoLineGap = ttSHORT(info->data+tab + 72);
+   return 1;
+}
+
+STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1)
+{
+   *x0 = ttSHORT(info->data + info->head + 36);
+   *y0 = ttSHORT(info->data + info->head + 38);
+   *x1 = ttSHORT(info->data + info->head + 40);
+   *y1 = ttSHORT(info->data + info->head + 42);
+}
+
+STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float height)
+{
+   int fheight = ttSHORT(info->data + info->hhea + 4) - ttSHORT(info->data + info->hhea + 6);
+   return (float) height / fheight;
+}
+
+STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels)
+{
+   int unitsPerEm = ttUSHORT(info->data + info->head + 18);
+   return pixels / unitsPerEm;
+}
+
+STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *v)
+{
+   STBTT_free(v, info->userdata);
+}
+
+STBTT_DEF stbtt_uint8 *stbtt_FindSVGDoc(const stbtt_fontinfo *info, int gl)
+{
+   int i;
+   stbtt_uint8 *data = info->data;
+   stbtt_uint8 *svg_doc_list = data + stbtt__get_svg((stbtt_fontinfo *) info);
+
+   int numEntries = ttUSHORT(svg_doc_list);
+   stbtt_uint8 *svg_docs = svg_doc_list + 2;
+
+   for(i=0; i<numEntries; i++) {
+      stbtt_uint8 *svg_doc = svg_docs + (12 * i);
+      if ((gl >= ttUSHORT(svg_doc)) && (gl <= ttUSHORT(svg_doc + 2)))
+         return svg_doc;
+   }
+   return 0;
+}
+
+STBTT_DEF int stbtt_GetGlyphSVG(const stbtt_fontinfo *info, int gl, const char **svg)
+{
+   stbtt_uint8 *data = info->data;
+   stbtt_uint8 *svg_doc;
+
+   if (info->svg == 0)
+      return 0;
+
+   svg_doc = stbtt_FindSVGDoc(info, gl);
+   if (svg_doc != NULL) {
+      *svg = (char *) data + info->svg + ttULONG(svg_doc + 4);
+      return ttULONG(svg_doc + 8);
+   } else {
+      return 0;
+   }
+}
+
+STBTT_DEF int stbtt_GetCodepointSVG(const stbtt_fontinfo *info, int unicode_codepoint, const char **svg)
+{
+   return stbtt_GetGlyphSVG(info, stbtt_FindGlyphIndex(info, unicode_codepoint), svg);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// antialiasing software rasterizer
+//
+
+STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y,float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1)
+{
+   int x0=0,y0=0,x1,y1; // =0 suppresses compiler warning
+   if (!stbtt_GetGlyphBox(font, glyph, &x0,&y0,&x1,&y1)) {
+      // e.g. space character
+      if (ix0) *ix0 = 0;
+      if (iy0) *iy0 = 0;
+      if (ix1) *ix1 = 0;
+      if (iy1) *iy1 = 0;
+   } else {
+      // move to integral bboxes (treating pixels as little squares, what pixels get touched)?
+      if (ix0) *ix0 = STBTT_ifloor( x0 * scale_x + shift_x);
+      if (iy0) *iy0 = STBTT_ifloor(-y1 * scale_y + shift_y);
+      if (ix1) *ix1 = STBTT_iceil ( x1 * scale_x + shift_x);
+      if (iy1) *iy1 = STBTT_iceil (-y0 * scale_y + shift_y);
+   }
+}
+
+STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1)
+{
+   stbtt_GetGlyphBitmapBoxSubpixel(font, glyph, scale_x, scale_y,0.0f,0.0f, ix0, iy0, ix1, iy1);
+}
+
+STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1)
+{
+   stbtt_GetGlyphBitmapBoxSubpixel(font, stbtt_FindGlyphIndex(font,codepoint), scale_x, scale_y,shift_x,shift_y, ix0,iy0,ix1,iy1);
+}
+
+STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1)
+{
+   stbtt_GetCodepointBitmapBoxSubpixel(font, codepoint, scale_x, scale_y,0.0f,0.0f, ix0,iy0,ix1,iy1);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+//  Rasterizer
+
+typedef struct stbtt__hheap_chunk
+{
+   struct stbtt__hheap_chunk *next;
+} stbtt__hheap_chunk;
+
+typedef struct stbtt__hheap
+{
+   struct stbtt__hheap_chunk *head;
+   void   *first_free;
+   int    num_remaining_in_head_chunk;
+} stbtt__hheap;
+
+static void *stbtt__hheap_alloc(stbtt__hheap *hh, size_t size, void *userdata)
+{
+   if (hh->first_free) {
+      void *p = hh->first_free;
+      hh->first_free = * (void **) p;
+      return p;
+   } else {
+      if (hh->num_remaining_in_head_chunk == 0) {
+         int count = (size < 32 ? 2000 : size < 128 ? 800 : 100);
+         stbtt__hheap_chunk *c = (stbtt__hheap_chunk *) STBTT_malloc(sizeof(stbtt__hheap_chunk) + size * count, userdata);
+         if (c == NULL)
+            return NULL;
+         c->next = hh->head;
+         hh->head = c;
+         hh->num_remaining_in_head_chunk = count;
+      }
+      --hh->num_remaining_in_head_chunk;
+      return (char *) (hh->head) + sizeof(stbtt__hheap_chunk) + size * hh->num_remaining_in_head_chunk;
+   }
+}
+
+static void stbtt__hheap_free(stbtt__hheap *hh, void *p)
+{
+   *(void **) p = hh->first_free;
+   hh->first_free = p;
+}
+
+static void stbtt__hheap_cleanup(stbtt__hheap *hh, void *userdata)
+{
+   stbtt__hheap_chunk *c = hh->head;
+   while (c) {
+      stbtt__hheap_chunk *n = c->next;
+      STBTT_free(c, userdata);
+      c = n;
+   }
+}
+
+typedef struct stbtt__edge {
+   float x0,y0, x1,y1;
+   int invert;
+} stbtt__edge;
+
+
+typedef struct stbtt__active_edge
+{
+   struct stbtt__active_edge *next;
+   #if STBTT_RASTERIZER_VERSION==1
+   int x,dx;
+   float ey;
+   int direction;
+   #elif STBTT_RASTERIZER_VERSION==2
+   float fx,fdx,fdy;
+   float direction;
+   float sy;
+   float ey;
+   #else
+   #error "Unrecognized value of STBTT_RASTERIZER_VERSION"
+   #endif
+} stbtt__active_edge;
+
+#if STBTT_RASTERIZER_VERSION == 1
+#define STBTT_FIXSHIFT   10
+#define STBTT_FIX        (1 << STBTT_FIXSHIFT)
+#define STBTT_FIXMASK    (STBTT_FIX-1)
+
+static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata)
+{
+   stbtt__active_edge *z = (stbtt__active_edge *) stbtt__hheap_alloc(hh, sizeof(*z), userdata);
+   float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
+   STBTT_assert(z != NULL);
+   if (!z) return z;
+
+   // round dx down to avoid overshooting
+   if (dxdy < 0)
+      z->dx = -STBTT_ifloor(STBTT_FIX * -dxdy);
+   else
+      z->dx = STBTT_ifloor(STBTT_FIX * dxdy);
+
+   z->x = STBTT_ifloor(STBTT_FIX * e->x0 + z->dx * (start_point - e->y0)); // use z->dx so when we offset later it's by the same amount
+   z->x -= off_x * STBTT_FIX;
+
+   z->ey = e->y1;
+   z->next = 0;
+   z->direction = e->invert ? 1 : -1;
+   return z;
+}
+#elif STBTT_RASTERIZER_VERSION == 2
+static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata)
+{
+   stbtt__active_edge *z = (stbtt__active_edge *) stbtt__hheap_alloc(hh, sizeof(*z), userdata);
+   float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
+   STBTT_assert(z != NULL);
+   //STBTT_assert(e->y0 <= start_point);
+   if (!z) return z;
+   z->fdx = dxdy;
+   z->fdy = dxdy != 0.0f ? (1.0f/dxdy) : 0.0f;
+   z->fx = e->x0 + dxdy * (start_point - e->y0);
+   z->fx -= off_x;
+   z->direction = e->invert ? 1.0f : -1.0f;
+   z->sy = e->y0;
+   z->ey = e->y1;
+   z->next = 0;
+   return z;
+}
+#else
+#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
+#endif
+
+#if STBTT_RASTERIZER_VERSION == 1
+// note: this routine clips fills that extend off the edges... ideally this
+// wouldn't happen, but it could happen if the truetype glyph bounding boxes
+// are wrong, or if the user supplies a too-small bitmap
+static void stbtt__fill_active_edges(unsigned char *scanline, int len, stbtt__active_edge *e, int max_weight)
+{
+   // non-zero winding fill
+   int x0=0, w=0;
+
+   while (e) {
+      if (w == 0) {
+         // if we're currently at zero, we need to record the edge start point
+         x0 = e->x; w += e->direction;
+      } else {
+         int x1 = e->x; w += e->direction;
+         // if we went to zero, we need to draw
+         if (w == 0) {
+            int i = x0 >> STBTT_FIXSHIFT;
+            int j = x1 >> STBTT_FIXSHIFT;
+
+            if (i < len && j >= 0) {
+               if (i == j) {
+                  // x0,x1 are the same pixel, so compute combined coverage
+                  scanline[i] = scanline[i] + (stbtt_uint8) ((x1 - x0) * max_weight >> STBTT_FIXSHIFT);
+               } else {
+                  if (i >= 0) // add antialiasing for x0
+                     scanline[i] = scanline[i] + (stbtt_uint8) (((STBTT_FIX - (x0 & STBTT_FIXMASK)) * max_weight) >> STBTT_FIXSHIFT);
+                  else
+                     i = -1; // clip
+
+                  if (j < len) // add antialiasing for x1
+                     scanline[j] = scanline[j] + (stbtt_uint8) (((x1 & STBTT_FIXMASK) * max_weight) >> STBTT_FIXSHIFT);
+                  else
+                     j = len; // clip
+
+                  for (++i; i < j; ++i) // fill pixels between x0 and x1
+                     scanline[i] = scanline[i] + (stbtt_uint8) max_weight;
+               }
+            }
+         }
+      }
+
+      e = e->next;
+   }
+}
+
+static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata)
+{
+   stbtt__hheap hh = { 0, 0, 0 };
+   stbtt__active_edge *active = NULL;
+   int y,j=0;
+   int max_weight = (255 / vsubsample);  // weight per vertical scanline
+   int s; // vertical subsample index
+   unsigned char scanline_data[512], *scanline;
+
+   if (result->w > 512)
+      scanline = (unsigned char *) STBTT_malloc(result->w, userdata);
+   else
+      scanline = scanline_data;
+
+   y = off_y * vsubsample;
+   e[n].y0 = (off_y + result->h) * (float) vsubsample + 1;
+
+   while (j < result->h) {
+      STBTT_memset(scanline, 0, result->w);
+      for (s=0; s < vsubsample; ++s) {
+         // find center of pixel for this scanline
+         float scan_y = y + 0.5f;
+         stbtt__active_edge **step = &active;
+
+         // update all active edges;
+         // remove all active edges that terminate before the center of this scanline
+         while (*step) {
+            stbtt__active_edge * z = *step;
+            if (z->ey <= scan_y) {
+               *step = z->next; // delete from list
+               STBTT_assert(z->direction);
+               z->direction = 0;
+               stbtt__hheap_free(&hh, z);
+            } else {
+               z->x += z->dx; // advance to position for current scanline
+               step = &((*step)->next); // advance through list
+            }
+         }
+
+         // resort the list if needed
+         for(;;) {
+            int changed=0;
+            step = &active;
+            while (*step && (*step)->next) {
+               if ((*step)->x > (*step)->next->x) {
+                  stbtt__active_edge *t = *step;
+                  stbtt__active_edge *q = t->next;
+
+                  t->next = q->next;
+                  q->next = t;
+                  *step = q;
+                  changed = 1;
+               }
+               step = &(*step)->next;
+            }
+            if (!changed) break;
+         }
+
+         // insert all edges that start before the center of this scanline -- omit ones that also end on this scanline
+         while (e->y0 <= scan_y) {
+            if (e->y1 > scan_y) {
+               stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y, userdata);
+               if (z != NULL) {
+                  // find insertion point
+                  if (active == NULL)
+                     active = z;
+                  else if (z->x < active->x) {
+                     // insert at front
+                     z->next = active;
+                     active = z;
+                  } else {
+                     // find thing to insert AFTER
+                     stbtt__active_edge *p = active;
+                     while (p->next && p->next->x < z->x)
+                        p = p->next;
+                     // at this point, p->next->x is NOT < z->x
+                     z->next = p->next;
+                     p->next = z;
+                  }
+               }
+            }
+            ++e;
+         }
+
+         // now process all active edges in XOR fashion
+         if (active)
+            stbtt__fill_active_edges(scanline, result->w, active, max_weight);
+
+         ++y;
+      }
+      STBTT_memcpy(result->pixels + j * result->stride, scanline, result->w);
+      ++j;
+   }
+
+   stbtt__hheap_cleanup(&hh, userdata);
+
+   if (scanline != scanline_data)
+      STBTT_free(scanline, userdata);
+}
+
+#elif STBTT_RASTERIZER_VERSION == 2
+
+// the edge passed in here does not cross the vertical line at x or the vertical line at x+1
+// (i.e. it has already been clipped to those)
+static void stbtt__handle_clipped_edge(float *scanline, int x, stbtt__active_edge *e, float x0, float y0, float x1, float y1)
+{
+   if (y0 == y1) return;
+   STBTT_assert(y0 < y1);
+   STBTT_assert(e->sy <= e->ey);
+   if (y0 > e->ey) return;
+   if (y1 < e->sy) return;
+   if (y0 < e->sy) {
+      x0 += (x1-x0) * (e->sy - y0) / (y1-y0);
+      y0 = e->sy;
+   }
+   if (y1 > e->ey) {
+      x1 += (x1-x0) * (e->ey - y1) / (y1-y0);
+      y1 = e->ey;
+   }
+
+   if (x0 == x)
+      STBTT_assert(x1 <= x+1);
+   else if (x0 == x+1)
+      STBTT_assert(x1 >= x);
+   else if (x0 <= x)
+      STBTT_assert(x1 <= x);
+   else if (x0 >= x+1)
+      STBTT_assert(x1 >= x+1);
+   else
+      STBTT_assert(x1 >= x && x1 <= x+1);
+
+   if (x0 <= x && x1 <= x)
+      scanline[x] += e->direction * (y1-y0);
+   else if (x0 >= x+1 && x1 >= x+1)
+      ;
+   else {
+      STBTT_assert(x0 >= x && x0 <= x+1 && x1 >= x && x1 <= x+1);
+      scanline[x] += e->direction * (y1-y0) * (1-((x0-x)+(x1-x))/2); // coverage = 1 - average x position
+   }
+}
+
+static float stbtt__sized_trapezoid_area(float height, float top_width, float bottom_width)
+{
+   STBTT_assert(top_width >= 0);
+   STBTT_assert(bottom_width >= 0);
+   return (top_width + bottom_width) / 2.0f * height;
+}
+
+static float stbtt__position_trapezoid_area(float height, float tx0, float tx1, float bx0, float bx1)
+{
+   return stbtt__sized_trapezoid_area(height, tx1 - tx0, bx1 - bx0);
+}
+
+static float stbtt__sized_triangle_area(float height, float width)
+{
+   return height * width / 2;
+}
+
+static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill, int len, stbtt__active_edge *e, float y_top)
+{
+   float y_bottom = y_top+1;
+
+   while (e) {
+      // brute force every pixel
+
+      // compute intersection points with top & bottom
+      STBTT_assert(e->ey >= y_top);
+
+      if (e->fdx == 0) {
+         float x0 = e->fx;
+         if (x0 < len) {
+            if (x0 >= 0) {
+               stbtt__handle_clipped_edge(scanline,(int) x0,e, x0,y_top, x0,y_bottom);
+               stbtt__handle_clipped_edge(scanline_fill-1,(int) x0+1,e, x0,y_top, x0,y_bottom);
+            } else {
+               stbtt__handle_clipped_edge(scanline_fill-1,0,e, x0,y_top, x0,y_bottom);
+            }
+         }
+      } else {
+         float x0 = e->fx;
+         float dx = e->fdx;
+         float xb = x0 + dx;
+         float x_top, x_bottom;
+         float sy0,sy1;
+         float dy = e->fdy;
+         STBTT_assert(e->sy <= y_bottom && e->ey >= y_top);
+
+         // compute endpoints of line segment clipped to this scanline (if the
+         // line segment starts on this scanline. x0 is the intersection of the
+         // line with y_top, but that may be off the line segment.
+         if (e->sy > y_top) {
+            x_top = x0 + dx * (e->sy - y_top);
+            sy0 = e->sy;
+         } else {
+            x_top = x0;
+            sy0 = y_top;
+         }
+         if (e->ey < y_bottom) {
+            x_bottom = x0 + dx * (e->ey - y_top);
+            sy1 = e->ey;
+         } else {
+            x_bottom = xb;
+            sy1 = y_bottom;
+         }
+
+         if (x_top >= 0 && x_bottom >= 0 && x_top < len && x_bottom < len) {
+            // from here on, we don't have to range check x values
+
+            if ((int) x_top == (int) x_bottom) {
+               float height;
+               // simple case, only spans one pixel
+               int x = (int) x_top;
+               height = (sy1 - sy0) * e->direction;
+               STBTT_assert(x >= 0 && x < len);
+               scanline[x]      += stbtt__position_trapezoid_area(height, x_top, x+1.0f, x_bottom, x+1.0f);
+               scanline_fill[x] += height; // everything right of this pixel is filled
+            } else {
+               int x,x1,x2;
+               float y_crossing, y_final, step, sign, area;
+               // covers 2+ pixels
+               if (x_top > x_bottom) {
+                  // flip scanline vertically; signed area is the same
+                  float t;
+                  sy0 = y_bottom - (sy0 - y_top);
+                  sy1 = y_bottom - (sy1 - y_top);
+                  t = sy0, sy0 = sy1, sy1 = t;
+                  t = x_bottom, x_bottom = x_top, x_top = t;
+                  dx = -dx;
+                  dy = -dy;
+                  t = x0, x0 = xb, xb = t;
+               }
+               STBTT_assert(dy >= 0);
+               STBTT_assert(dx >= 0);
+
+               x1 = (int) x_top;
+               x2 = (int) x_bottom;
+               // compute intersection with y axis at x1+1
+               y_crossing = y_top + dy * (x1+1 - x0);
+
+               // compute intersection with y axis at x2
+               y_final = y_top + dy * (x2 - x0);
+
+               //           x1    x_top                            x2    x_bottom
+               //     y_top  +------|-----+------------+------------+--------|---+------------+
+               //            |            |            |            |            |            |
+               //            |            |            |            |            |            |
+               //       sy0  |      Txxxxx|............|............|............|............|
+               // y_crossing |            *xxxxx.......|............|............|............|
+               //            |            |     xxxxx..|............|............|............|
+               //            |            |     /-   xx*xxxx........|............|............|
+               //            |            | dy <       |    xxxxxx..|............|............|
+               //   y_final  |            |     \-     |          xx*xxx.........|............|
+               //       sy1  |            |            |            |   xxxxxB...|............|
+               //            |            |            |            |            |            |
+               //            |            |            |            |            |            |
+               //  y_bottom  +------------+------------+------------+------------+------------+
+               //
+               // goal is to measure the area covered by '.' in each pixel
+
+               // if x2 is right at the right edge of x1, y_crossing can blow up, github #1057
+               // @TODO: maybe test against sy1 rather than y_bottom?
+               if (y_crossing > y_bottom)
+                  y_crossing = y_bottom;
+
+               sign = e->direction;
+
+               // area of the rectangle covered from sy0..y_crossing
+               area = sign * (y_crossing-sy0);
+
+               // area of the triangle (x_top,sy0), (x1+1,sy0), (x1+1,y_crossing)
+               scanline[x1] += stbtt__sized_triangle_area(area, x1+1 - x_top);
+
+               // check if final y_crossing is blown up; no test case for this
+               if (y_final > y_bottom) {
+                  y_final = y_bottom;
+                  dy = (y_final - y_crossing ) / (x2 - (x1+1)); // if denom=0, y_final = y_crossing, so y_final <= y_bottom
+               }
+
+               // in second pixel, area covered by line segment found in first pixel
+               // is always a rectangle 1 wide * the height of that line segment; this
+               // is exactly what the variable 'area' stores. it also gets a contribution
+               // from the line segment within it. the THIRD pixel will get the first
+               // pixel's rectangle contribution, the second pixel's rectangle contribution,
+               // and its own contribution. the 'own contribution' is the same in every pixel except
+               // the leftmost and rightmost, a trapezoid that slides down in each pixel.
+               // the second pixel's contribution to the third pixel will be the
+               // rectangle 1 wide times the height change in the second pixel, which is dy.
+
+               step = sign * dy * 1; // dy is dy/dx, change in y for every 1 change in x,
+               // which multiplied by 1-pixel-width is how much pixel area changes for each step in x
+               // so the area advances by 'step' every time
+
+               for (x = x1+1; x < x2; ++x) {
+                  scanline[x] += area + step/2; // area of trapezoid is 1*step/2
+                  area += step;
+               }
+               STBTT_assert(STBTT_fabs(area) <= 1.01f); // accumulated error from area += step unless we round step down
+               STBTT_assert(sy1 > y_final-0.01f);
+
+               // area covered in the last pixel is the rectangle from all the pixels to the left,
+               // plus the trapezoid filled by the line segment in this pixel all the way to the right edge
+               scanline[x2] += area + sign * stbtt__position_trapezoid_area(sy1-y_final, (float) x2, x2+1.0f, x_bottom, x2+1.0f);
+
+               // the rest of the line is filled based on the total height of the line segment in this pixel
+               scanline_fill[x2] += sign * (sy1-sy0);
+            }
+         } else {
+            // if edge goes outside of box we're drawing, we require
+            // clipping logic. since this does not match the intended use
+            // of this library, we use a different, very slow brute
+            // force implementation
+            // note though that this does happen some of the time because
+            // x_top and x_bottom can be extrapolated at the top & bottom of
+            // the shape and actually lie outside the bounding box
+            int x;
+            for (x=0; x < len; ++x) {
+               // cases:
+               //
+               // there can be up to two intersections with the pixel. any intersection
+               // with left or right edges can be handled by splitting into two (or three)
+               // regions. intersections with top & bottom do not necessitate case-wise logic.
+               //
+               // the old way of doing this found the intersections with the left & right edges,
+               // then used some simple logic to produce up to three segments in sorted order
+               // from top-to-bottom. however, this had a problem: if an x edge was epsilon
+               // across the x border, then the corresponding y position might not be distinct
+               // from the other y segment, and it might ignored as an empty segment. to avoid
+               // that, we need to explicitly produce segments based on x positions.
+
+               // rename variables to clearly-defined pairs
+               float y0 = y_top;
+               float x1 = (float) (x);
+               float x2 = (float) (x+1);
+               float x3 = xb;
+               float y3 = y_bottom;
+
+               // x = e->x + e->dx * (y-y_top)
+               // (y-y_top) = (x - e->x) / e->dx
+               // y = (x - e->x) / e->dx + y_top
+               float y1 = (x - x0) / dx + y_top;
+               float y2 = (x+1 - x0) / dx + y_top;
+
+               if (x0 < x1 && x3 > x2) {         // three segments descending down-right
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
+                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x2,y2);
+                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
+               } else if (x3 < x1 && x0 > x2) {  // three segments descending down-left
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
+                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x1,y1);
+                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
+               } else if (x0 < x1 && x3 > x1) {  // two segments across x, down-right
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
+                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
+               } else if (x3 < x1 && x0 > x1) {  // two segments across x, down-left
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
+                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
+               } else if (x0 < x2 && x3 > x2) {  // two segments across x+1, down-right
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
+                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
+               } else if (x3 < x2 && x0 > x2) {  // two segments across x+1, down-left
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
+                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
+               } else {  // one segment
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x3,y3);
+               }
+            }
+         }
+      }
+      e = e->next;
+   }
+}
+
+// directly AA rasterize edges w/o supersampling
+static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata)
+{
+   stbtt__hheap hh = { 0, 0, 0 };
+   stbtt__active_edge *active = NULL;
+   int y,j=0, i;
+   float scanline_data[129], *scanline, *scanline2;
+
+   STBTT__NOTUSED(vsubsample);
+
+   if (result->w > 64)
+      scanline = (float *) STBTT_malloc((result->w*2+1) * sizeof(float), userdata);
+   else
+      scanline = scanline_data;
+
+   scanline2 = scanline + result->w;
+
+   y = off_y;
+   e[n].y0 = (float) (off_y + result->h) + 1;
+
+   while (j < result->h) {
+      // find center of pixel for this scanline
+      float scan_y_top    = y + 0.0f;
+      float scan_y_bottom = y + 1.0f;
+      stbtt__active_edge **step = &active;
+
+      STBTT_memset(scanline , 0, result->w*sizeof(scanline[0]));
+      STBTT_memset(scanline2, 0, (result->w+1)*sizeof(scanline[0]));
+
+      // update all active edges;
+      // remove all active edges that terminate before the top of this scanline
+      while (*step) {
+         stbtt__active_edge * z = *step;
+         if (z->ey <= scan_y_top) {
+            *step = z->next; // delete from list
+            STBTT_assert(z->direction);
+            z->direction = 0;
+            stbtt__hheap_free(&hh, z);
+         } else {
+            step = &((*step)->next); // advance through list
+         }
+      }
+
+      // insert all edges that start before the bottom of this scanline
+      while (e->y0 <= scan_y_bottom) {
+         if (e->y0 != e->y1) {
+            stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y_top, userdata);
+            if (z != NULL) {
+               if (j == 0 && off_y != 0) {
+                  if (z->ey < scan_y_top) {
+                     // this can happen due to subpixel positioning and some kind of fp rounding error i think
+                     z->ey = scan_y_top;
+                  }
+               }
+               STBTT_assert(z->ey >= scan_y_top); // if we get really unlucky a tiny bit of an edge can be out of bounds
+               // insert at front
+               z->next = active;
+               active = z;
+            }
+         }
+         ++e;
+      }
+
+      // now process all active edges
+      if (active)
+         stbtt__fill_active_edges_new(scanline, scanline2+1, result->w, active, scan_y_top);
+
+      {
+         float sum = 0;
+         for (i=0; i < result->w; ++i) {
+            float k;
+            int m;
+            sum += scanline2[i];
+            k = scanline[i] + sum;
+            k = (float) STBTT_fabs(k)*255 + 0.5f;
+            m = (int) k;
+            if (m > 255) m = 255;
+            result->pixels[j*result->stride + i] = (unsigned char) m;
+         }
+      }
+      // advance all the edges
+      step = &active;
+      while (*step) {
+         stbtt__active_edge *z = *step;
+         z->fx += z->fdx; // advance to position for current scanline
+         step = &((*step)->next); // advance through list
+      }
+
+      ++y;
+      ++j;
+   }
+
+   stbtt__hheap_cleanup(&hh, userdata);
+
+   if (scanline != scanline_data)
+      STBTT_free(scanline, userdata);
+}
+#else
+#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
+#endif
+
+#define STBTT__COMPARE(a,b)  ((a)->y0 < (b)->y0)
+
+static void stbtt__sort_edges_ins_sort(stbtt__edge *p, int n)
+{
+   int i,j;
+   for (i=1; i < n; ++i) {
+      stbtt__edge t = p[i], *a = &t;
+      j = i;
+      while (j > 0) {
+         stbtt__edge *b = &p[j-1];
+         int c = STBTT__COMPARE(a,b);
+         if (!c) break;
+         p[j] = p[j-1];
+         --j;
+      }
+      if (i != j)
+         p[j] = t;
+   }
+}
+
+static void stbtt__sort_edges_quicksort(stbtt__edge *p, int n)
+{
+   /* threshold for transitioning to insertion sort */
+   while (n > 12) {
+      stbtt__edge t;
+      int c01,c12,c,m,i,j;
+
+      /* compute median of three */
+      m = n >> 1;
+      c01 = STBTT__COMPARE(&p[0],&p[m]);
+      c12 = STBTT__COMPARE(&p[m],&p[n-1]);
+      /* if 0 >= mid >= end, or 0 < mid < end, then use mid */
+      if (c01 != c12) {
+         /* otherwise, we'll need to swap something else to middle */
+         int z;
+         c = STBTT__COMPARE(&p[0],&p[n-1]);
+         /* 0>mid && mid<n:  0>n => n; 0<n => 0 */
+         /* 0<mid && mid>n:  0>n => 0; 0<n => n */
+         z = (c == c12) ? 0 : n-1;
+         t = p[z];
+         p[z] = p[m];
+         p[m] = t;
+      }
+      /* now p[m] is the median-of-three */
+      /* swap it to the beginning so it won't move around */
+      t = p[0];
+      p[0] = p[m];
+      p[m] = t;
+
+      /* partition loop */
+      i=1;
+      j=n-1;
+      for(;;) {
+         /* handling of equality is crucial here */
+         /* for sentinels & efficiency with duplicates */
+         for (;;++i) {
+            if (!STBTT__COMPARE(&p[i], &p[0])) break;
+         }
+         for (;;--j) {
+            if (!STBTT__COMPARE(&p[0], &p[j])) break;
+         }
+         /* make sure we haven't crossed */
+         if (i >= j) break;
+         t = p[i];
+         p[i] = p[j];
+         p[j] = t;
+
+         ++i;
+         --j;
+      }
+      /* recurse on smaller side, iterate on larger */
+      if (j < (n-i)) {
+         stbtt__sort_edges_quicksort(p,j);
+         p = p+i;
+         n = n-i;
+      } else {
+         stbtt__sort_edges_quicksort(p+i, n-i);
+         n = j;
+      }
+   }
+}
+
+static void stbtt__sort_edges(stbtt__edge *p, int n)
+{
+   stbtt__sort_edges_quicksort(p, n);
+   stbtt__sort_edges_ins_sort(p, n);
+}
+
+typedef struct
+{
+   float x,y;
+} stbtt__point;
+
+static void stbtt__rasterize(stbtt__bitmap *result, stbtt__point *pts, int *wcount, int windings, float scale_x, float scale_y, float shift_x, float shift_y, int off_x, int off_y, int invert, void *userdata)
+{
+   float y_scale_inv = invert ? -scale_y : scale_y;
+   stbtt__edge *e;
+   int n,i,j,k,m;
+#if STBTT_RASTERIZER_VERSION == 1
+   int vsubsample = result->h < 8 ? 15 : 5;
+#elif STBTT_RASTERIZER_VERSION == 2
+   int vsubsample = 1;
+#else
+   #error "Unrecognized value of STBTT_RASTERIZER_VERSION"
+#endif
+   // vsubsample should divide 255 evenly; otherwise we won't reach full opacity
+
+   // now we have to blow out the windings into explicit edge lists
+   n = 0;
+   for (i=0; i < windings; ++i)
+      n += wcount[i];
+
+   e = (stbtt__edge *) STBTT_malloc(sizeof(*e) * (n+1), userdata); // add an extra one as a sentinel
+   if (e == 0) return;
+   n = 0;
+
+   m=0;
+   for (i=0; i < windings; ++i) {
+      stbtt__point *p = pts + m;
+      m += wcount[i];
+      j = wcount[i]-1;
+      for (k=0; k < wcount[i]; j=k++) {
+         int a=k,b=j;
+         // skip the edge if horizontal
+         if (p[j].y == p[k].y)
+            continue;
+         // add edge from j to k to the list
+         e[n].invert = 0;
+         if (invert ? p[j].y > p[k].y : p[j].y < p[k].y) {
+            e[n].invert = 1;
+            a=j,b=k;
+         }
+         e[n].x0 = p[a].x * scale_x + shift_x;
+         e[n].y0 = (p[a].y * y_scale_inv + shift_y) * vsubsample;
+         e[n].x1 = p[b].x * scale_x + shift_x;
+         e[n].y1 = (p[b].y * y_scale_inv + shift_y) * vsubsample;
+         ++n;
+      }
+   }
+
+   // now sort the edges by their highest point (should snap to integer, and then by x)
+   //STBTT_sort(e, n, sizeof(e[0]), stbtt__edge_compare);
+   stbtt__sort_edges(e, n);
+
+   // now, traverse the scanlines and find the intersections on each scanline, use xor winding rule
+   stbtt__rasterize_sorted_edges(result, e, n, vsubsample, off_x, off_y, userdata);
+
+   STBTT_free(e, userdata);
+}
+
+static void stbtt__add_point(stbtt__point *points, int n, float x, float y)
+{
+   if (!points) return; // during first pass, it's unallocated
+   points[n].x = x;
+   points[n].y = y;
+}
+
+// tessellate until threshold p is happy... @TODO warped to compensate for non-linear stretching
+static int stbtt__tesselate_curve(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float objspace_flatness_squared, int n)
+{
+   // midpoint
+   float mx = (x0 + 2*x1 + x2)/4;
+   float my = (y0 + 2*y1 + y2)/4;
+   // versus directly drawn line
+   float dx = (x0+x2)/2 - mx;
+   float dy = (y0+y2)/2 - my;
+   if (n > 16) // 65536 segments on one curve better be enough!
+      return 1;
+   if (dx*dx+dy*dy > objspace_flatness_squared) { // half-pixel error allowed... need to be smaller if AA
+      stbtt__tesselate_curve(points, num_points, x0,y0, (x0+x1)/2.0f,(y0+y1)/2.0f, mx,my, objspace_flatness_squared,n+1);
+      stbtt__tesselate_curve(points, num_points, mx,my, (x1+x2)/2.0f,(y1+y2)/2.0f, x2,y2, objspace_flatness_squared,n+1);
+   } else {
+      stbtt__add_point(points, *num_points,x2,y2);
+      *num_points = *num_points+1;
+   }
+   return 1;
+}
+
+static void stbtt__tesselate_cubic(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float x3, float y3, float objspace_flatness_squared, int n)
+{
+   // @TODO this "flatness" calculation is just made-up nonsense that seems to work well enough
+   float dx0 = x1-x0;
+   float dy0 = y1-y0;
+   float dx1 = x2-x1;
+   float dy1 = y2-y1;
+   float dx2 = x3-x2;
+   float dy2 = y3-y2;
+   float dx = x3-x0;
+   float dy = y3-y0;
+   float longlen = (float) (STBTT_sqrt(dx0*dx0+dy0*dy0)+STBTT_sqrt(dx1*dx1+dy1*dy1)+STBTT_sqrt(dx2*dx2+dy2*dy2));
+   float shortlen = (float) STBTT_sqrt(dx*dx+dy*dy);
+   float flatness_squared = longlen*longlen-shortlen*shortlen;
+
+   if (n > 16) // 65536 segments on one curve better be enough!
+      return;
+
+   if (flatness_squared > objspace_flatness_squared) {
+      float x01 = (x0+x1)/2;
+      float y01 = (y0+y1)/2;
+      float x12 = (x1+x2)/2;
+      float y12 = (y1+y2)/2;
+      float x23 = (x2+x3)/2;
+      float y23 = (y2+y3)/2;
+
+      float xa = (x01+x12)/2;
+      float ya = (y01+y12)/2;
+      float xb = (x12+x23)/2;
+      float yb = (y12+y23)/2;
+
+      float mx = (xa+xb)/2;
+      float my = (ya+yb)/2;
+
+      stbtt__tesselate_cubic(points, num_points, x0,y0, x01,y01, xa,ya, mx,my, objspace_flatness_squared,n+1);
+      stbtt__tesselate_cubic(points, num_points, mx,my, xb,yb, x23,y23, x3,y3, objspace_flatness_squared,n+1);
+   } else {
+      stbtt__add_point(points, *num_points,x3,y3);
+      *num_points = *num_points+1;
+   }
+}
+
+// returns number of contours
+static stbtt__point *stbtt_FlattenCurves(stbtt_vertex *vertices, int num_verts, float objspace_flatness, int **contour_lengths, int *num_contours, void *userdata)
+{
+   stbtt__point *points=0;
+   int num_points=0;
+
+   float objspace_flatness_squared = objspace_flatness * objspace_flatness;
+   int i,n=0,start=0, pass;
+
+   // count how many "moves" there are to get the contour count
+   for (i=0; i < num_verts; ++i)
+      if (vertices[i].type == STBTT_vmove)
+         ++n;
+
+   *num_contours = n;
+   if (n == 0) return 0;
+
+   *contour_lengths = (int *) STBTT_malloc(sizeof(**contour_lengths) * n, userdata);
+
+   if (*contour_lengths == 0) {
+      *num_contours = 0;
+      return 0;
+   }
+
+   // make two passes through the points so we don't need to realloc
+   for (pass=0; pass < 2; ++pass) {
+      float x=0,y=0;
+      if (pass == 1) {
+         points = (stbtt__point *) STBTT_malloc(num_points * sizeof(points[0]), userdata);
+         if (points == NULL) goto error;
+      }
+      num_points = 0;
+      n= -1;
+      for (i=0; i < num_verts; ++i) {
+         switch (vertices[i].type) {
+            case STBTT_vmove:
+               // start the next contour
+               if (n >= 0)
+                  (*contour_lengths)[n] = num_points - start;
+               ++n;
+               start = num_points;
+
+               x = vertices[i].x, y = vertices[i].y;
+               stbtt__add_point(points, num_points++, x,y);
+               break;
+            case STBTT_vline:
+               x = vertices[i].x, y = vertices[i].y;
+               stbtt__add_point(points, num_points++, x, y);
+               break;
+            case STBTT_vcurve:
+               stbtt__tesselate_curve(points, &num_points, x,y,
+                                        vertices[i].cx, vertices[i].cy,
+                                        vertices[i].x,  vertices[i].y,
+                                        objspace_flatness_squared, 0);
+               x = vertices[i].x, y = vertices[i].y;
+               break;
+            case STBTT_vcubic:
+               stbtt__tesselate_cubic(points, &num_points, x,y,
+                                        vertices[i].cx, vertices[i].cy,
+                                        vertices[i].cx1, vertices[i].cy1,
+                                        vertices[i].x,  vertices[i].y,
+                                        objspace_flatness_squared, 0);
+               x = vertices[i].x, y = vertices[i].y;
+               break;
+         }
+      }
+      (*contour_lengths)[n] = num_points - start;
+   }
+
+   return points;
+error:
+   STBTT_free(points, userdata);
+   STBTT_free(*contour_lengths, userdata);
+   *contour_lengths = 0;
+   *num_contours = 0;
+   return NULL;
+}
+
+STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result, float flatness_in_pixels, stbtt_vertex *vertices, int num_verts, float scale_x, float scale_y, float shift_x, float shift_y, int x_off, int y_off, int invert, void *userdata)
+{
+   float scale            = scale_x > scale_y ? scale_y : scale_x;
+   int winding_count      = 0;
+   int *winding_lengths   = NULL;
+   stbtt__point *windings = stbtt_FlattenCurves(vertices, num_verts, flatness_in_pixels / scale, &winding_lengths, &winding_count, userdata);
+   if (windings) {
+      stbtt__rasterize(result, windings, winding_lengths, winding_count, scale_x, scale_y, shift_x, shift_y, x_off, y_off, invert, userdata);
+      STBTT_free(winding_lengths, userdata);
+      STBTT_free(windings, userdata);
+   }
+}
+
+STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata)
+{
+   STBTT_free(bitmap, userdata);
+}
+
+STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff)
+{
+   int ix0,iy0,ix1,iy1;
+   stbtt__bitmap gbm;
+   stbtt_vertex *vertices;
+   int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices);
+
+   if (scale_x == 0) scale_x = scale_y;
+   if (scale_y == 0) {
+      if (scale_x == 0) {
+         STBTT_free(vertices, info->userdata);
+         return NULL;
+      }
+      scale_y = scale_x;
+   }
+
+   stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0,&iy0,&ix1,&iy1);
+
+   // now we get the size
+   gbm.w = (ix1 - ix0);
+   gbm.h = (iy1 - iy0);
+   gbm.pixels = NULL; // in case we error
+
+   if (width ) *width  = gbm.w;
+   if (height) *height = gbm.h;
+   if (xoff  ) *xoff   = ix0;
+   if (yoff  ) *yoff   = iy0;
+
+   if (gbm.w && gbm.h) {
+      gbm.pixels = (unsigned char *) STBTT_malloc(gbm.w * gbm.h, info->userdata);
+      if (gbm.pixels) {
+         gbm.stride = gbm.w;
+
+         stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0, iy0, 1, info->userdata);
+      }
+   }
+   STBTT_free(vertices, info->userdata);
+   return gbm.pixels;
+}
+
+STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff)
+{
+   return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y, 0.0f, 0.0f, glyph, width, height, xoff, yoff);
+}
+
+STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph)
+{
+   int ix0,iy0;
+   stbtt_vertex *vertices;
+   int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices);
+   stbtt__bitmap gbm;
+
+   stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0,&iy0,0,0);
+   gbm.pixels = output;
+   gbm.w = out_w;
+   gbm.h = out_h;
+   gbm.stride = out_stride;
+
+   if (gbm.w && gbm.h)
+      stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0,iy0, 1, info->userdata);
+
+   STBTT_free(vertices, info->userdata);
+}
+
+STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph)
+{
+   stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f,0.0f, glyph);
+}
+
+STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff)
+{
+   return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y,shift_x,shift_y, stbtt_FindGlyphIndex(info,codepoint), width,height,xoff,yoff);
+}
+
+STBTT_DEF void stbtt_MakeCodepointBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int codepoint)
+{
+   stbtt_MakeGlyphBitmapSubpixelPrefilter(info, output, out_w, out_h, out_stride, scale_x, scale_y, shift_x, shift_y, oversample_x, oversample_y, sub_x, sub_y, stbtt_FindGlyphIndex(info,codepoint));
+}
+
+STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint)
+{
+   stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, shift_x, shift_y, stbtt_FindGlyphIndex(info,codepoint));
+}
+
+STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff)
+{
+   return stbtt_GetCodepointBitmapSubpixel(info, scale_x, scale_y, 0.0f,0.0f, codepoint, width,height,xoff,yoff);
+}
+
+STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint)
+{
+   stbtt_MakeCodepointBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f,0.0f, codepoint);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// bitmap baking
+//
+// This is SUPER-CRAPPY packing to keep source code small
+
+static int stbtt_BakeFontBitmap_internal(unsigned char *data, int offset,  // font location (use offset=0 for plain .ttf)
+                                float pixel_height,                     // height of font in pixels
+                                unsigned char *pixels, int pw, int ph,  // bitmap to be filled in
+                                int first_char, int num_chars,          // characters to bake
+                                stbtt_bakedchar *chardata)
+{
+   float scale;
+   int x,y,bottom_y, i;
+   stbtt_fontinfo f;
+   f.userdata = NULL;
+   if (!stbtt_InitFont(&f, data, offset))
+      return -1;
+   STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels
+   x=y=1;
+   bottom_y = 1;
+
+   scale = stbtt_ScaleForPixelHeight(&f, pixel_height);
+
+   for (i=0; i < num_chars; ++i) {
+      int advance, lsb, x0,y0,x1,y1,gw,gh;
+      int g = stbtt_FindGlyphIndex(&f, first_char + i);
+      stbtt_GetGlyphHMetrics(&f, g, &advance, &lsb);
+      stbtt_GetGlyphBitmapBox(&f, g, scale,scale, &x0,&y0,&x1,&y1);
+      gw = x1-x0;
+      gh = y1-y0;
+      if (x + gw + 1 >= pw)
+         y = bottom_y, x = 1; // advance to next row
+      if (y + gh + 1 >= ph) // check if it fits vertically AFTER potentially moving to next row
+         return -i;
+      STBTT_assert(x+gw < pw);
+      STBTT_assert(y+gh < ph);
+      stbtt_MakeGlyphBitmap(&f, pixels+x+y*pw, gw,gh,pw, scale,scale, g);
+      chardata[i].x0 = (stbtt_int16) x;
+      chardata[i].y0 = (stbtt_int16) y;
+      chardata[i].x1 = (stbtt_int16) (x + gw);
+      chardata[i].y1 = (stbtt_int16) (y + gh);
+      chardata[i].xadvance = scale * advance;
+      chardata[i].xoff     = (float) x0;
+      chardata[i].yoff     = (float) y0;
+      x = x + gw + 1;
+      if (y+gh+1 > bottom_y)
+         bottom_y = y+gh+1;
+   }
+   return bottom_y;
+}
+
+STBTT_DEF void stbtt_GetBakedQuad(const stbtt_bakedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int opengl_fillrule)
+{
+   float d3d_bias = opengl_fillrule ? 0 : -0.5f;
+   float ipw = 1.0f / pw, iph = 1.0f / ph;
+   const stbtt_bakedchar *b = chardata + char_index;
+   int round_x = STBTT_ifloor((*xpos + b->xoff) + 0.5f);
+   int round_y = STBTT_ifloor((*ypos + b->yoff) + 0.5f);
+
+   q->x0 = round_x + d3d_bias;
+   q->y0 = round_y + d3d_bias;
+   q->x1 = round_x + b->x1 - b->x0 + d3d_bias;
+   q->y1 = round_y + b->y1 - b->y0 + d3d_bias;
+
+   q->s0 = b->x0 * ipw;
+   q->t0 = b->y0 * iph;
+   q->s1 = b->x1 * ipw;
+   q->t1 = b->y1 * iph;
+
+   *xpos += b->xadvance;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// rectangle packing replacement routines if you don't have stb_rect_pack.h
+//
+
+#ifndef STB_RECT_PACK_VERSION
+
+typedef int stbrp_coord;
+
+////////////////////////////////////////////////////////////////////////////////////
+//                                                                                //
+//                                                                                //
+// COMPILER WARNING ?!?!?                                                         //
+//                                                                                //
+//                                                                                //
+// if you get a compile warning due to these symbols being defined more than      //
+// once, move #include "stb_rect_pack.h" before #include "stb_truetype.h"         //
+//                                                                                //
+////////////////////////////////////////////////////////////////////////////////////
+
+typedef struct
+{
+   int width,height;
+   int x,y,bottom_y;
+} stbrp_context;
+
+typedef struct
+{
+   unsigned char x;
+} stbrp_node;
+
+struct stbrp_rect
+{
+   stbrp_coord x,y;
+   int id,w,h,was_packed;
+};
+
+static void stbrp_init_target(stbrp_context *con, int pw, int ph, stbrp_node *nodes, int num_nodes)
+{
+   con->width  = pw;
+   con->height = ph;
+   con->x = 0;
+   con->y = 0;
+   con->bottom_y = 0;
+   STBTT__NOTUSED(nodes);
+   STBTT__NOTUSED(num_nodes);
+}
+
+static void stbrp_pack_rects(stbrp_context *con, stbrp_rect *rects, int num_rects)
+{
+   int i;
+   for (i=0; i < num_rects; ++i) {
+      if (con->x + rects[i].w > con->width) {
+         con->x = 0;
+         con->y = con->bottom_y;
+      }
+      if (con->y + rects[i].h > con->height)
+         break;
+      rects[i].x = con->x;
+      rects[i].y = con->y;
+      rects[i].was_packed = 1;
+      con->x += rects[i].w;
+      if (con->y + rects[i].h > con->bottom_y)
+         con->bottom_y = con->y + rects[i].h;
+   }
+   for (   ; i < num_rects; ++i)
+      rects[i].was_packed = 0;
+}
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// bitmap baking
+//
+// This is SUPER-AWESOME (tm Ryan Gordon) packing using stb_rect_pack.h. If
+// stb_rect_pack.h isn't available, it uses the BakeFontBitmap strategy.
+
+STBTT_DEF int stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int pw, int ph, int stride_in_bytes, int padding, void *alloc_context)
+{
+   stbrp_context *context = (stbrp_context *) STBTT_malloc(sizeof(*context)            ,alloc_context);
+   int            num_nodes = pw - padding;
+   stbrp_node    *nodes   = (stbrp_node    *) STBTT_malloc(sizeof(*nodes  ) * num_nodes,alloc_context);
+
+   if (context == NULL || nodes == NULL) {
+      if (context != NULL) STBTT_free(context, alloc_context);
+      if (nodes   != NULL) STBTT_free(nodes  , alloc_context);
+      return 0;
+   }
+
+   spc->user_allocator_context = alloc_context;
+   spc->width = pw;
+   spc->height = ph;
+   spc->pixels = pixels;
+   spc->pack_info = context;
+   spc->nodes = nodes;
+   spc->padding = padding;
+   spc->stride_in_bytes = stride_in_bytes != 0 ? stride_in_bytes : pw;
+   spc->h_oversample = 1;
+   spc->v_oversample = 1;
+   spc->skip_missing = 0;
+
+   stbrp_init_target(context, pw-padding, ph-padding, nodes, num_nodes);
+
+   if (pixels)
+      STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels
+
+   return 1;
+}
+
+STBTT_DEF void stbtt_PackEnd  (stbtt_pack_context *spc)
+{
+   STBTT_free(spc->nodes    , spc->user_allocator_context);
+   STBTT_free(spc->pack_info, spc->user_allocator_context);
+}
+
+STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample)
+{
+   STBTT_assert(h_oversample <= STBTT_MAX_OVERSAMPLE);
+   STBTT_assert(v_oversample <= STBTT_MAX_OVERSAMPLE);
+   if (h_oversample <= STBTT_MAX_OVERSAMPLE)
+      spc->h_oversample = h_oversample;
+   if (v_oversample <= STBTT_MAX_OVERSAMPLE)
+      spc->v_oversample = v_oversample;
+}
+
+STBTT_DEF void stbtt_PackSetSkipMissingCodepoints(stbtt_pack_context *spc, int skip)
+{
+   spc->skip_missing = skip;
+}
+
+#define STBTT__OVER_MASK  (STBTT_MAX_OVERSAMPLE-1)
+
+static void stbtt__h_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width)
+{
+   unsigned char buffer[STBTT_MAX_OVERSAMPLE];
+   int safe_w = w - kernel_width;
+   int j;
+   STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze
+   for (j=0; j < h; ++j) {
+      int i;
+      unsigned int total;
+      STBTT_memset(buffer, 0, kernel_width);
+
+      total = 0;
+
+      // make kernel_width a constant in common cases so compiler can optimize out the divide
+      switch (kernel_width) {
+         case 2:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / 2);
+            }
+            break;
+         case 3:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / 3);
+            }
+            break;
+         case 4:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / 4);
+            }
+            break;
+         case 5:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / 5);
+            }
+            break;
+         default:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / kernel_width);
+            }
+            break;
+      }
+
+      for (; i < w; ++i) {
+         STBTT_assert(pixels[i] == 0);
+         total -= buffer[i & STBTT__OVER_MASK];
+         pixels[i] = (unsigned char) (total / kernel_width);
+      }
+
+      pixels += stride_in_bytes;
+   }
+}
+
+static void stbtt__v_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width)
+{
+   unsigned char buffer[STBTT_MAX_OVERSAMPLE];
+   int safe_h = h - kernel_width;
+   int j;
+   STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze
+   for (j=0; j < w; ++j) {
+      int i;
+      unsigned int total;
+      STBTT_memset(buffer, 0, kernel_width);
+
+      total = 0;
+
+      // make kernel_width a constant in common cases so compiler can optimize out the divide
+      switch (kernel_width) {
+         case 2:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / 2);
+            }
+            break;
+         case 3:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / 3);
+            }
+            break;
+         case 4:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / 4);
+            }
+            break;
+         case 5:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / 5);
+            }
+            break;
+         default:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / kernel_width);
+            }
+            break;
+      }
+
+      for (; i < h; ++i) {
+         STBTT_assert(pixels[i*stride_in_bytes] == 0);
+         total -= buffer[i & STBTT__OVER_MASK];
+         pixels[i*stride_in_bytes] = (unsigned char) (total / kernel_width);
+      }
+
+      pixels += 1;
+   }
+}
+
+static float stbtt__oversample_shift(int oversample)
+{
+   if (!oversample)
+      return 0.0f;
+
+   // The prefilter is a box filter of width "oversample",
+   // which shifts phase by (oversample - 1)/2 pixels in
+   // oversampled space. We want to shift in the opposite
+   // direction to counter this.
+   return (float)-(oversample - 1) / (2.0f * (float)oversample);
+}
+
+// rects array must be big enough to accommodate all characters in the given ranges
+STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
+{
+   int i,j,k;
+   int missing_glyph_added = 0;
+
+   k=0;
+   for (i=0; i < num_ranges; ++i) {
+      float fh = ranges[i].font_size;
+      float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh);
+      ranges[i].h_oversample = (unsigned char) spc->h_oversample;
+      ranges[i].v_oversample = (unsigned char) spc->v_oversample;
+      for (j=0; j < ranges[i].num_chars; ++j) {
+         int x0,y0,x1,y1;
+         int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
+         int glyph = stbtt_FindGlyphIndex(info, codepoint);
+         if (glyph == 0 && (spc->skip_missing || missing_glyph_added)) {
+            rects[k].w = rects[k].h = 0;
+         } else {
+            stbtt_GetGlyphBitmapBoxSubpixel(info,glyph,
+                                            scale * spc->h_oversample,
+                                            scale * spc->v_oversample,
+                                            0,0,
+                                            &x0,&y0,&x1,&y1);
+            rects[k].w = (stbrp_coord) (x1-x0 + spc->padding + spc->h_oversample-1);
+            rects[k].h = (stbrp_coord) (y1-y0 + spc->padding + spc->v_oversample-1);
+            if (glyph == 0)
+               missing_glyph_added = 1;
+         }
+         ++k;
+      }
+   }
+
+   return k;
+}
+
+STBTT_DEF void stbtt_MakeGlyphBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int prefilter_x, int prefilter_y, float *sub_x, float *sub_y, int glyph)
+{
+   stbtt_MakeGlyphBitmapSubpixel(info,
+                                 output,
+                                 out_w - (prefilter_x - 1),
+                                 out_h - (prefilter_y - 1),
+                                 out_stride,
+                                 scale_x,
+                                 scale_y,
+                                 shift_x,
+                                 shift_y,
+                                 glyph);
+
+   if (prefilter_x > 1)
+      stbtt__h_prefilter(output, out_w, out_h, out_stride, prefilter_x);
+
+   if (prefilter_y > 1)
+      stbtt__v_prefilter(output, out_w, out_h, out_stride, prefilter_y);
+
+   *sub_x = stbtt__oversample_shift(prefilter_x);
+   *sub_y = stbtt__oversample_shift(prefilter_y);
+}
+
+// rects array must be big enough to accommodate all characters in the given ranges
+STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
+{
+   int i,j,k, missing_glyph = -1, return_value = 1;
+
+   // save current values
+   int old_h_over = spc->h_oversample;
+   int old_v_over = spc->v_oversample;
+
+   k = 0;
+   for (i=0; i < num_ranges; ++i) {
+      float fh = ranges[i].font_size;
+      float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh);
+      float recip_h,recip_v,sub_x,sub_y;
+      spc->h_oversample = ranges[i].h_oversample;
+      spc->v_oversample = ranges[i].v_oversample;
+      recip_h = 1.0f / spc->h_oversample;
+      recip_v = 1.0f / spc->v_oversample;
+      sub_x = stbtt__oversample_shift(spc->h_oversample);
+      sub_y = stbtt__oversample_shift(spc->v_oversample);
+      for (j=0; j < ranges[i].num_chars; ++j) {
+         stbrp_rect *r = &rects[k];
+         if (r->was_packed && r->w != 0 && r->h != 0) {
+            stbtt_packedchar *bc = &ranges[i].chardata_for_range[j];
+            int advance, lsb, x0,y0,x1,y1;
+            int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
+            int glyph = stbtt_FindGlyphIndex(info, codepoint);
+            stbrp_coord pad = (stbrp_coord) spc->padding;
+
+            // pad on left and top
+            r->x += pad;
+            r->y += pad;
+            r->w -= pad;
+            r->h -= pad;
+            stbtt_GetGlyphHMetrics(info, glyph, &advance, &lsb);
+            stbtt_GetGlyphBitmapBox(info, glyph,
+                                    scale * spc->h_oversample,
+                                    scale * spc->v_oversample,
+                                    &x0,&y0,&x1,&y1);
+            stbtt_MakeGlyphBitmapSubpixel(info,
+                                          spc->pixels + r->x + r->y*spc->stride_in_bytes,
+                                          r->w - spc->h_oversample+1,
+                                          r->h - spc->v_oversample+1,
+                                          spc->stride_in_bytes,
+                                          scale * spc->h_oversample,
+                                          scale * spc->v_oversample,
+                                          0,0,
+                                          glyph);
+
+            if (spc->h_oversample > 1)
+               stbtt__h_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes,
+                                  r->w, r->h, spc->stride_in_bytes,
+                                  spc->h_oversample);
+
+            if (spc->v_oversample > 1)
+               stbtt__v_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes,
+                                  r->w, r->h, spc->stride_in_bytes,
+                                  spc->v_oversample);
+
+            bc->x0       = (stbtt_int16)  r->x;
+            bc->y0       = (stbtt_int16)  r->y;
+            bc->x1       = (stbtt_int16) (r->x + r->w);
+            bc->y1       = (stbtt_int16) (r->y + r->h);
+            bc->xadvance =                scale * advance;
+            bc->xoff     =       (float)  x0 * recip_h + sub_x;
+            bc->yoff     =       (float)  y0 * recip_v + sub_y;
+            bc->xoff2    =                (x0 + r->w) * recip_h + sub_x;
+            bc->yoff2    =                (y0 + r->h) * recip_v + sub_y;
+
+            if (glyph == 0)
+               missing_glyph = j;
+         } else if (spc->skip_missing) {
+            return_value = 0;
+         } else if (r->was_packed && r->w == 0 && r->h == 0 && missing_glyph >= 0) {
+            ranges[i].chardata_for_range[j] = ranges[i].chardata_for_range[missing_glyph];
+         } else {
+            return_value = 0; // if any fail, report failure
+         }
+
+         ++k;
+      }
+   }
+
+   // restore original values
+   spc->h_oversample = old_h_over;
+   spc->v_oversample = old_v_over;
+
+   return return_value;
+}
+
+STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects)
+{
+   stbrp_pack_rects((stbrp_context *) spc->pack_info, rects, num_rects);
+}
+
+STBTT_DEF int stbtt_PackFontRanges(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges)
+{
+   stbtt_fontinfo info;
+   int i,j,n, return_value = 1;
+   //stbrp_context *context = (stbrp_context *) spc->pack_info;
+   stbrp_rect    *rects;
+
+   // flag all characters as NOT packed
+   for (i=0; i < num_ranges; ++i)
+      for (j=0; j < ranges[i].num_chars; ++j)
+         ranges[i].chardata_for_range[j].x0 =
+         ranges[i].chardata_for_range[j].y0 =
+         ranges[i].chardata_for_range[j].x1 =
+         ranges[i].chardata_for_range[j].y1 = 0;
+
+   n = 0;
+   for (i=0; i < num_ranges; ++i)
+      n += ranges[i].num_chars;
+
+   rects = (stbrp_rect *) STBTT_malloc(sizeof(*rects) * n, spc->user_allocator_context);
+   if (rects == NULL)
+      return 0;
+
+   info.userdata = spc->user_allocator_context;
+   stbtt_InitFont(&info, fontdata, stbtt_GetFontOffsetForIndex(fontdata,font_index));
+
+   n = stbtt_PackFontRangesGatherRects(spc, &info, ranges, num_ranges, rects);
+
+   stbtt_PackFontRangesPackRects(spc, rects, n);
+
+   return_value = stbtt_PackFontRangesRenderIntoRects(spc, &info, ranges, num_ranges, rects);
+
+   STBTT_free(rects, spc->user_allocator_context);
+   return return_value;
+}
+
+STBTT_DEF int stbtt_PackFontRange(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, float font_size,
+            int first_unicode_codepoint_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range)
+{
+   stbtt_pack_range range;
+   range.first_unicode_codepoint_in_range = first_unicode_codepoint_in_range;
+   range.array_of_unicode_codepoints = NULL;
+   range.num_chars                   = num_chars_in_range;
+   range.chardata_for_range          = chardata_for_range;
+   range.font_size                   = font_size;
+   return stbtt_PackFontRanges(spc, fontdata, font_index, &range, 1);
+}
+
+STBTT_DEF void stbtt_GetScaledFontVMetrics(const unsigned char *fontdata, int index, float size, float *ascent, float *descent, float *lineGap)
+{
+   int i_ascent, i_descent, i_lineGap;
+   float scale;
+   stbtt_fontinfo info;
+   stbtt_InitFont(&info, fontdata, stbtt_GetFontOffsetForIndex(fontdata, index));
+   scale = size > 0 ? stbtt_ScaleForPixelHeight(&info, size) : stbtt_ScaleForMappingEmToPixels(&info, -size);
+   stbtt_GetFontVMetrics(&info, &i_ascent, &i_descent, &i_lineGap);
+   *ascent  = (float) i_ascent  * scale;
+   *descent = (float) i_descent * scale;
+   *lineGap = (float) i_lineGap * scale;
+}
+
+STBTT_DEF void stbtt_GetPackedQuad(const stbtt_packedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int align_to_integer)
+{
+   float ipw = 1.0f / pw, iph = 1.0f / ph;
+   const stbtt_packedchar *b = chardata + char_index;
+
+   if (align_to_integer) {
+      float x = (float) STBTT_ifloor((*xpos + b->xoff) + 0.5f);
+      float y = (float) STBTT_ifloor((*ypos + b->yoff) + 0.5f);
+      q->x0 = x;
+      q->y0 = y;
+      q->x1 = x + b->xoff2 - b->xoff;
+      q->y1 = y + b->yoff2 - b->yoff;
+   } else {
+      q->x0 = *xpos + b->xoff;
+      q->y0 = *ypos + b->yoff;
+      q->x1 = *xpos + b->xoff2;
+      q->y1 = *ypos + b->yoff2;
+   }
+
+   q->s0 = b->x0 * ipw;
+   q->t0 = b->y0 * iph;
+   q->s1 = b->x1 * ipw;
+   q->t1 = b->y1 * iph;
+
+   *xpos += b->xadvance;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// sdf computation
+//
+
+#define STBTT_min(a,b)  ((a) < (b) ? (a) : (b))
+#define STBTT_max(a,b)  ((a) < (b) ? (b) : (a))
+
+static int stbtt__ray_intersect_bezier(float orig[2], float ray[2], float q0[2], float q1[2], float q2[2], float hits[2][2])
+{
+   float q0perp = q0[1]*ray[0] - q0[0]*ray[1];
+   float q1perp = q1[1]*ray[0] - q1[0]*ray[1];
+   float q2perp = q2[1]*ray[0] - q2[0]*ray[1];
+   float roperp = orig[1]*ray[0] - orig[0]*ray[1];
+
+   float a = q0perp - 2*q1perp + q2perp;
+   float b = q1perp - q0perp;
+   float c = q0perp - roperp;
+
+   float s0 = 0., s1 = 0.;
+   int num_s = 0;
+
+   if (a != 0.0) {
+      float discr = b*b - a*c;
+      if (discr > 0.0) {
+         float rcpna = -1 / a;
+         float d = (float) STBTT_sqrt(discr);
+         s0 = (b+d) * rcpna;
+         s1 = (b-d) * rcpna;
+         if (s0 >= 0.0 && s0 <= 1.0)
+            num_s = 1;
+         if (d > 0.0 && s1 >= 0.0 && s1 <= 1.0) {
+            if (num_s == 0) s0 = s1;
+            ++num_s;
+         }
+      }
+   } else {
+      // 2*b*s + c = 0
+      // s = -c / (2*b)
+      s0 = c / (-2 * b);
+      if (s0 >= 0.0 && s0 <= 1.0)
+         num_s = 1;
+   }
+
+   if (num_s == 0)
+      return 0;
+   else {
+      float rcp_len2 = 1 / (ray[0]*ray[0] + ray[1]*ray[1]);
+      float rayn_x = ray[0] * rcp_len2, rayn_y = ray[1] * rcp_len2;
+
+      float q0d =   q0[0]*rayn_x +   q0[1]*rayn_y;
+      float q1d =   q1[0]*rayn_x +   q1[1]*rayn_y;
+      float q2d =   q2[0]*rayn_x +   q2[1]*rayn_y;
+      float rod = orig[0]*rayn_x + orig[1]*rayn_y;
+
+      float q10d = q1d - q0d;
+      float q20d = q2d - q0d;
+      float q0rd = q0d - rod;
+
+      hits[0][0] = q0rd + s0*(2.0f - 2.0f*s0)*q10d + s0*s0*q20d;
+      hits[0][1] = a*s0+b;
+
+      if (num_s > 1) {
+         hits[1][0] = q0rd + s1*(2.0f - 2.0f*s1)*q10d + s1*s1*q20d;
+         hits[1][1] = a*s1+b;
+         return 2;
+      } else {
+         return 1;
+      }
+   }
+}
+
+static int equal(float *a, float *b)
+{
+   return (a[0] == b[0] && a[1] == b[1]);
+}
+
+static int stbtt__compute_crossings_x(float x, float y, int nverts, stbtt_vertex *verts)
+{
+   int i;
+   float orig[2], ray[2] = { 1, 0 };
+   float y_frac;
+   int winding = 0;
+
+   // make sure y never passes through a vertex of the shape
+   y_frac = (float) STBTT_fmod(y, 1.0f);
+   if (y_frac < 0.01f)
+      y += 0.01f;
+   else if (y_frac > 0.99f)
+      y -= 0.01f;
+
+   orig[0] = x;
+   orig[1] = y;
+
+   // test a ray from (-infinity,y) to (x,y)
+   for (i=0; i < nverts; ++i) {
+      if (verts[i].type == STBTT_vline) {
+         int x0 = (int) verts[i-1].x, y0 = (int) verts[i-1].y;
+         int x1 = (int) verts[i  ].x, y1 = (int) verts[i  ].y;
+         if (y > STBTT_min(y0,y1) && y < STBTT_max(y0,y1) && x > STBTT_min(x0,x1)) {
+            float x_inter = (y - y0) / (y1 - y0) * (x1-x0) + x0;
+            if (x_inter < x)
+               winding += (y0 < y1) ? 1 : -1;
+         }
+      }
+      if (verts[i].type == STBTT_vcurve) {
+         int x0 = (int) verts[i-1].x , y0 = (int) verts[i-1].y ;
+         int x1 = (int) verts[i  ].cx, y1 = (int) verts[i  ].cy;
+         int x2 = (int) verts[i  ].x , y2 = (int) verts[i  ].y ;
+         int ax = STBTT_min(x0,STBTT_min(x1,x2)), ay = STBTT_min(y0,STBTT_min(y1,y2));
+         int by = STBTT_max(y0,STBTT_max(y1,y2));
+         if (y > ay && y < by && x > ax) {
+            float q0[2],q1[2],q2[2];
+            float hits[2][2];
+            q0[0] = (float)x0;
+            q0[1] = (float)y0;
+            q1[0] = (float)x1;
+            q1[1] = (float)y1;
+            q2[0] = (float)x2;
+            q2[1] = (float)y2;
+            if (equal(q0,q1) || equal(q1,q2)) {
+               x0 = (int)verts[i-1].x;
+               y0 = (int)verts[i-1].y;
+               x1 = (int)verts[i  ].x;
+               y1 = (int)verts[i  ].y;
+               if (y > STBTT_min(y0,y1) && y < STBTT_max(y0,y1) && x > STBTT_min(x0,x1)) {
+                  float x_inter = (y - y0) / (y1 - y0) * (x1-x0) + x0;
+                  if (x_inter < x)
+                     winding += (y0 < y1) ? 1 : -1;
+               }
+            } else {
+               int num_hits = stbtt__ray_intersect_bezier(orig, ray, q0, q1, q2, hits);
+               if (num_hits >= 1)
+                  if (hits[0][0] < 0)
+                     winding += (hits[0][1] < 0 ? -1 : 1);
+               if (num_hits >= 2)
+                  if (hits[1][0] < 0)
+                     winding += (hits[1][1] < 0 ? -1 : 1);
+            }
+         }
+      }
+   }
+   return winding;
+}
+
+static float stbtt__cuberoot( float x )
+{
+   if (x<0)
+      return -(float) STBTT_pow(-x,1.0f/3.0f);
+   else
+      return  (float) STBTT_pow( x,1.0f/3.0f);
+}
+
+// x^3 + a*x^2 + b*x + c = 0
+static int stbtt__solve_cubic(float a, float b, float c, float* r)
+{
+   float s = -a / 3;
+   float p = b - a*a / 3;
+   float q = a * (2*a*a - 9*b) / 27 + c;
+   float p3 = p*p*p;
+   float d = q*q + 4*p3 / 27;
+   if (d >= 0) {
+      float z = (float) STBTT_sqrt(d);
+      float u = (-q + z) / 2;
+      float v = (-q - z) / 2;
+      u = stbtt__cuberoot(u);
+      v = stbtt__cuberoot(v);
+      r[0] = s + u + v;
+      return 1;
+   } else {
+      float u = (float) STBTT_sqrt(-p/3);
+      float v = (float) STBTT_acos(-STBTT_sqrt(-27/p3) * q / 2) / 3; // p3 must be negative, since d is negative
+      float m = (float) STBTT_cos(v);
+      float n = (float) STBTT_cos(v-3.141592/2)*1.732050808f;
+      r[0] = s + u * 2 * m;
+      r[1] = s - u * (m + n);
+      r[2] = s - u * (m - n);
+
+      //STBTT_assert( STBTT_fabs(((r[0]+a)*r[0]+b)*r[0]+c) < 0.05f);  // these asserts may not be safe at all scales, though they're in bezier t parameter units so maybe?
+      //STBTT_assert( STBTT_fabs(((r[1]+a)*r[1]+b)*r[1]+c) < 0.05f);
+      //STBTT_assert( STBTT_fabs(((r[2]+a)*r[2]+b)*r[2]+c) < 0.05f);
+      return 3;
+   }
+}
+
+STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float scale, int glyph, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff)
+{
+   float scale_x = scale, scale_y = scale;
+   int ix0,iy0,ix1,iy1;
+   int w,h;
+   unsigned char *data;
+
+   if (scale == 0) return NULL;
+
+   stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale, scale, 0.0f,0.0f, &ix0,&iy0,&ix1,&iy1);
+
+   // if empty, return NULL
+   if (ix0 == ix1 || iy0 == iy1)
+      return NULL;
+
+   ix0 -= padding;
+   iy0 -= padding;
+   ix1 += padding;
+   iy1 += padding;
+
+   w = (ix1 - ix0);
+   h = (iy1 - iy0);
+
+   if (width ) *width  = w;
+   if (height) *height = h;
+   if (xoff  ) *xoff   = ix0;
+   if (yoff  ) *yoff   = iy0;
+
+   // invert for y-downwards bitmaps
+   scale_y = -scale_y;
+
+   {
+      // distance from singular values (in the same units as the pixel grid)
+      const float eps = 1./1024, eps2 = eps*eps;
+      int x,y,i,j;
+      float *precompute;
+      stbtt_vertex *verts;
+      int num_verts = stbtt_GetGlyphShape(info, glyph, &verts);
+      data = (unsigned char *) STBTT_malloc(w * h, info->userdata);
+      precompute = (float *) STBTT_malloc(num_verts * sizeof(float), info->userdata);
+
+      for (i=0,j=num_verts-1; i < num_verts; j=i++) {
+         if (verts[i].type == STBTT_vline) {
+            float x0 = verts[i].x*scale_x, y0 = verts[i].y*scale_y;
+            float x1 = verts[j].x*scale_x, y1 = verts[j].y*scale_y;
+            float dist = (float) STBTT_sqrt((x1-x0)*(x1-x0) + (y1-y0)*(y1-y0));
+            precompute[i] = (dist < eps) ? 0.0f : 1.0f / dist;
+         } else if (verts[i].type == STBTT_vcurve) {
+            float x2 = verts[j].x *scale_x, y2 = verts[j].y *scale_y;
+            float x1 = verts[i].cx*scale_x, y1 = verts[i].cy*scale_y;
+            float x0 = verts[i].x *scale_x, y0 = verts[i].y *scale_y;
+            float bx = x0 - 2*x1 + x2, by = y0 - 2*y1 + y2;
+            float len2 = bx*bx + by*by;
+            if (len2 >= eps2)
+               precompute[i] = 1.0f / len2;
+            else
+               precompute[i] = 0.0f;
+         } else
+            precompute[i] = 0.0f;
+      }
+
+      for (y=iy0; y < iy1; ++y) {
+         for (x=ix0; x < ix1; ++x) {
+            float val;
+            float min_dist = 999999.0f;
+            float sx = (float) x + 0.5f;
+            float sy = (float) y + 0.5f;
+            float x_gspace = (sx / scale_x);
+            float y_gspace = (sy / scale_y);
+
+            int winding = stbtt__compute_crossings_x(x_gspace, y_gspace, num_verts, verts); // @OPTIMIZE: this could just be a rasterization, but needs to be line vs. non-tesselated curves so a new path
+
+            for (i=0; i < num_verts; ++i) {
+               float x0 = verts[i].x*scale_x, y0 = verts[i].y*scale_y;
+
+               if (verts[i].type == STBTT_vline && precompute[i] != 0.0f) {
+                  float x1 = verts[i-1].x*scale_x, y1 = verts[i-1].y*scale_y;
+
+                  float dist,dist2 = (x0-sx)*(x0-sx) + (y0-sy)*(y0-sy);
+                  if (dist2 < min_dist*min_dist)
+                     min_dist = (float) STBTT_sqrt(dist2);
+
+                  // coarse culling against bbox
+                  //if (sx > STBTT_min(x0,x1)-min_dist && sx < STBTT_max(x0,x1)+min_dist &&
+                  //    sy > STBTT_min(y0,y1)-min_dist && sy < STBTT_max(y0,y1)+min_dist)
+                  dist = (float) STBTT_fabs((x1-x0)*(y0-sy) - (y1-y0)*(x0-sx)) * precompute[i];
+                  STBTT_assert(i != 0);
+                  if (dist < min_dist) {
+                     // check position along line
+                     // x' = x0 + t*(x1-x0), y' = y0 + t*(y1-y0)
+                     // minimize (x'-sx)*(x'-sx)+(y'-sy)*(y'-sy)
+                     float dx = x1-x0, dy = y1-y0;
+                     float px = x0-sx, py = y0-sy;
+                     // minimize (px+t*dx)^2 + (py+t*dy)^2 = px*px + 2*px*dx*t + t^2*dx*dx + py*py + 2*py*dy*t + t^2*dy*dy
+                     // derivative: 2*px*dx + 2*py*dy + (2*dx*dx+2*dy*dy)*t, set to 0 and solve
+                     float t = -(px*dx + py*dy) / (dx*dx + dy*dy);
+                     if (t >= 0.0f && t <= 1.0f)
+                        min_dist = dist;
+                  }
+               } else if (verts[i].type == STBTT_vcurve) {
+                  float x2 = verts[i-1].x *scale_x, y2 = verts[i-1].y *scale_y;
+                  float x1 = verts[i  ].cx*scale_x, y1 = verts[i  ].cy*scale_y;
+                  float box_x0 = STBTT_min(STBTT_min(x0,x1),x2);
+                  float box_y0 = STBTT_min(STBTT_min(y0,y1),y2);
+                  float box_x1 = STBTT_max(STBTT_max(x0,x1),x2);
+                  float box_y1 = STBTT_max(STBTT_max(y0,y1),y2);
+                  // coarse culling against bbox to avoid computing cubic unnecessarily
+                  if (sx > box_x0-min_dist && sx < box_x1+min_dist && sy > box_y0-min_dist && sy < box_y1+min_dist) {
+                     int num=0;
+                     float ax = x1-x0, ay = y1-y0;
+                     float bx = x0 - 2*x1 + x2, by = y0 - 2*y1 + y2;
+                     float mx = x0 - sx, my = y0 - sy;
+                     float res[3] = {0.f,0.f,0.f};
+                     float px,py,t,it,dist2;
+                     float a_inv = precompute[i];
+                     if (a_inv == 0.0) { // if a_inv is 0, it's 2nd degree so use quadratic formula
+                        float a = 3*(ax*bx + ay*by);
+                        float b = 2*(ax*ax + ay*ay) + (mx*bx+my*by);
+                        float c = mx*ax+my*ay;
+                        if (STBTT_fabs(a) < eps2) { // if a is 0, it's linear
+                           if (STBTT_fabs(b) >= eps2) {
+                              res[num++] = -c/b;
+                           }
+                        } else {
+                           float discriminant = b*b - 4*a*c;
+                           if (discriminant < 0)
+                              num = 0;
+                           else {
+                              float root = (float) STBTT_sqrt(discriminant);
+                              res[0] = (-b - root)/(2*a);
+                              res[1] = (-b + root)/(2*a);
+                              num = 2; // don't bother distinguishing 1-solution case, as code below will still work
+                           }
+                        }
+                     } else {
+                        float b = 3*(ax*bx + ay*by) * a_inv; // could precompute this as it doesn't depend on sample point
+                        float c = (2*(ax*ax + ay*ay) + (mx*bx+my*by)) * a_inv;
+                        float d = (mx*ax+my*ay) * a_inv;
+                        num = stbtt__solve_cubic(b, c, d, res);
+                     }
+                     dist2 = (x0-sx)*(x0-sx) + (y0-sy)*(y0-sy);
+                     if (dist2 < min_dist*min_dist)
+                        min_dist = (float) STBTT_sqrt(dist2);
+
+                     if (num >= 1 && res[0] >= 0.0f && res[0] <= 1.0f) {
+                        t = res[0], it = 1.0f - t;
+                        px = it*it*x0 + 2*t*it*x1 + t*t*x2;
+                        py = it*it*y0 + 2*t*it*y1 + t*t*y2;
+                        dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy);
+                        if (dist2 < min_dist * min_dist)
+                           min_dist = (float) STBTT_sqrt(dist2);
+                     }
+                     if (num >= 2 && res[1] >= 0.0f && res[1] <= 1.0f) {
+                        t = res[1], it = 1.0f - t;
+                        px = it*it*x0 + 2*t*it*x1 + t*t*x2;
+                        py = it*it*y0 + 2*t*it*y1 + t*t*y2;
+                        dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy);
+                        if (dist2 < min_dist * min_dist)
+                           min_dist = (float) STBTT_sqrt(dist2);
+                     }
+                     if (num >= 3 && res[2] >= 0.0f && res[2] <= 1.0f) {
+                        t = res[2], it = 1.0f - t;
+                        px = it*it*x0 + 2*t*it*x1 + t*t*x2;
+                        py = it*it*y0 + 2*t*it*y1 + t*t*y2;
+                        dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy);
+                        if (dist2 < min_dist * min_dist)
+                           min_dist = (float) STBTT_sqrt(dist2);
+                     }
+                  }
+               }
+            }
+            if (winding == 0)
+               min_dist = -min_dist;  // if outside the shape, value is negative
+            val = onedge_value + pixel_dist_scale * min_dist;
+            if (val < 0)
+               val = 0;
+            else if (val > 255)
+               val = 255;
+            data[(y-iy0)*w+(x-ix0)] = (unsigned char) val;
+         }
+      }
+      STBTT_free(precompute, info->userdata);
+      STBTT_free(verts, info->userdata);
+   }
+   return data;
+}
+
+STBTT_DEF unsigned char * stbtt_GetCodepointSDF(const stbtt_fontinfo *info, float scale, int codepoint, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff)
+{
+   return stbtt_GetGlyphSDF(info, scale, stbtt_FindGlyphIndex(info, codepoint), padding, onedge_value, pixel_dist_scale, width, height, xoff, yoff);
+}
+
+STBTT_DEF void stbtt_FreeSDF(unsigned char *bitmap, void *userdata)
+{
+   STBTT_free(bitmap, userdata);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// font name matching -- recommended not to use this
+//
+
+// check if a utf8 string contains a prefix which is the utf16 string; if so return length of matching utf8 string
+static stbtt_int32 stbtt__CompareUTF8toUTF16_bigendian_prefix(stbtt_uint8 *s1, stbtt_int32 len1, stbtt_uint8 *s2, stbtt_int32 len2)
+{
+   stbtt_int32 i=0;
+
+   // convert utf16 to utf8 and compare the results while converting
+   while (len2) {
+      stbtt_uint16 ch = s2[0]*256 + s2[1];
+      if (ch < 0x80) {
+         if (i >= len1) return -1;
+         if (s1[i++] != ch) return -1;
+      } else if (ch < 0x800) {
+         if (i+1 >= len1) return -1;
+         if (s1[i++] != 0xc0 + (ch >> 6)) return -1;
+         if (s1[i++] != 0x80 + (ch & 0x3f)) return -1;
+      } else if (ch >= 0xd800 && ch < 0xdc00) {
+         stbtt_uint32 c;
+         stbtt_uint16 ch2 = s2[2]*256 + s2[3];
+         if (i+3 >= len1) return -1;
+         c = ((ch - 0xd800) << 10) + (ch2 - 0xdc00) + 0x10000;
+         if (s1[i++] != 0xf0 + (c >> 18)) return -1;
+         if (s1[i++] != 0x80 + ((c >> 12) & 0x3f)) return -1;
+         if (s1[i++] != 0x80 + ((c >>  6) & 0x3f)) return -1;
+         if (s1[i++] != 0x80 + ((c      ) & 0x3f)) return -1;
+         s2 += 2; // plus another 2 below
+         len2 -= 2;
+      } else if (ch >= 0xdc00 && ch < 0xe000) {
+         return -1;
+      } else {
+         if (i+2 >= len1) return -1;
+         if (s1[i++] != 0xe0 + (ch >> 12)) return -1;
+         if (s1[i++] != 0x80 + ((ch >> 6) & 0x3f)) return -1;
+         if (s1[i++] != 0x80 + ((ch     ) & 0x3f)) return -1;
+      }
+      s2 += 2;
+      len2 -= 2;
+   }
+   return i;
+}
+
+static int stbtt_CompareUTF8toUTF16_bigendian_internal(char *s1, int len1, char *s2, int len2)
+{
+   return len1 == stbtt__CompareUTF8toUTF16_bigendian_prefix((stbtt_uint8*) s1, len1, (stbtt_uint8*) s2, len2);
+}
+
+// returns results in whatever encoding you request... but note that 2-byte encodings
+// will be BIG-ENDIAN... use stbtt_CompareUTF8toUTF16_bigendian() to compare
+STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID)
+{
+   stbtt_int32 i,count,stringOffset;
+   stbtt_uint8 *fc = font->data;
+   stbtt_uint32 offset = font->fontstart;
+   stbtt_uint32 nm = stbtt__find_table(fc, offset, "name");
+   if (!nm) return NULL;
+
+   count = ttUSHORT(fc+nm+2);
+   stringOffset = nm + ttUSHORT(fc+nm+4);
+   for (i=0; i < count; ++i) {
+      stbtt_uint32 loc = nm + 6 + 12 * i;
+      if (platformID == ttUSHORT(fc+loc+0) && encodingID == ttUSHORT(fc+loc+2)
+          && languageID == ttUSHORT(fc+loc+4) && nameID == ttUSHORT(fc+loc+6)) {
+         *length = ttUSHORT(fc+loc+8);
+         return (const char *) (fc+stringOffset+ttUSHORT(fc+loc+10));
+      }
+   }
+   return NULL;
+}
+
+static int stbtt__matchpair(stbtt_uint8 *fc, stbtt_uint32 nm, stbtt_uint8 *name, stbtt_int32 nlen, stbtt_int32 target_id, stbtt_int32 next_id)
+{
+   stbtt_int32 i;
+   stbtt_int32 count = ttUSHORT(fc+nm+2);
+   stbtt_int32 stringOffset = nm + ttUSHORT(fc+nm+4);
+
+   for (i=0; i < count; ++i) {
+      stbtt_uint32 loc = nm + 6 + 12 * i;
+      stbtt_int32 id = ttUSHORT(fc+loc+6);
+      if (id == target_id) {
+         // find the encoding
+         stbtt_int32 platform = ttUSHORT(fc+loc+0), encoding = ttUSHORT(fc+loc+2), language = ttUSHORT(fc+loc+4);
+
+         // is this a Unicode encoding?
+         if (platform == 0 || (platform == 3 && encoding == 1) || (platform == 3 && encoding == 10)) {
+            stbtt_int32 slen = ttUSHORT(fc+loc+8);
+            stbtt_int32 off = ttUSHORT(fc+loc+10);
+
+            // check if there's a prefix match
+            stbtt_int32 matchlen = stbtt__CompareUTF8toUTF16_bigendian_prefix(name, nlen, fc+stringOffset+off,slen);
+            if (matchlen >= 0) {
+               // check for target_id+1 immediately following, with same encoding & language
+               if (i+1 < count && ttUSHORT(fc+loc+12+6) == next_id && ttUSHORT(fc+loc+12) == platform && ttUSHORT(fc+loc+12+2) == encoding && ttUSHORT(fc+loc+12+4) == language) {
+                  slen = ttUSHORT(fc+loc+12+8);
+                  off = ttUSHORT(fc+loc+12+10);
+                  if (slen == 0) {
+                     if (matchlen == nlen)
+                        return 1;
+                  } else if (matchlen < nlen && name[matchlen] == ' ') {
+                     ++matchlen;
+                     if (stbtt_CompareUTF8toUTF16_bigendian_internal((char*) (name+matchlen), nlen-matchlen, (char*)(fc+stringOffset+off),slen))
+                        return 1;
+                  }
+               } else {
+                  // if nothing immediately following
+                  if (matchlen == nlen)
+                     return 1;
+               }
+            }
+         }
+
+         // @TODO handle other encodings
+      }
+   }
+   return 0;
+}
+
+static int stbtt__matches(stbtt_uint8 *fc, stbtt_uint32 offset, stbtt_uint8 *name, stbtt_int32 flags)
+{
+   stbtt_int32 nlen = (stbtt_int32) STBTT_strlen((char *) name);
+   stbtt_uint32 nm,hd;
+   if (!stbtt__isfont(fc+offset)) return 0;
+
+   // check italics/bold/underline flags in macStyle...
+   if (flags) {
+      hd = stbtt__find_table(fc, offset, "head");
+      if ((ttUSHORT(fc+hd+44) & 7) != (flags & 7)) return 0;
+   }
+
+   nm = stbtt__find_table(fc, offset, "name");
+   if (!nm) return 0;
+
+   if (flags) {
+      // if we checked the macStyle flags, then just check the family and ignore the subfamily
+      if (stbtt__matchpair(fc, nm, name, nlen, 16, -1))  return 1;
+      if (stbtt__matchpair(fc, nm, name, nlen,  1, -1))  return 1;
+      if (stbtt__matchpair(fc, nm, name, nlen,  3, -1))  return 1;
+   } else {
+      if (stbtt__matchpair(fc, nm, name, nlen, 16, 17))  return 1;
+      if (stbtt__matchpair(fc, nm, name, nlen,  1,  2))  return 1;
+      if (stbtt__matchpair(fc, nm, name, nlen,  3, -1))  return 1;
+   }
+
+   return 0;
+}
+
+static int stbtt_FindMatchingFont_internal(unsigned char *font_collection, char *name_utf8, stbtt_int32 flags)
+{
+   stbtt_int32 i;
+   for (i=0;;++i) {
+      stbtt_int32 off = stbtt_GetFontOffsetForIndex(font_collection, i);
+      if (off < 0) return off;
+      if (stbtt__matches((stbtt_uint8 *) font_collection, off, (stbtt_uint8*) name_utf8, flags))
+         return off;
+   }
+}
+
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-qual"
+#endif
+
+STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset,
+                                float pixel_height, unsigned char *pixels, int pw, int ph,
+                                int first_char, int num_chars, stbtt_bakedchar *chardata)
+{
+   return stbtt_BakeFontBitmap_internal((unsigned char *) data, offset, pixel_height, pixels, pw, ph, first_char, num_chars, chardata);
+}
+
+STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index)
+{
+   return stbtt_GetFontOffsetForIndex_internal((unsigned char *) data, index);
+}
+
+STBTT_DEF int stbtt_GetNumberOfFonts(const unsigned char *data)
+{
+   return stbtt_GetNumberOfFonts_internal((unsigned char *) data);
+}
+
+STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset)
+{
+   return stbtt_InitFont_internal(info, (unsigned char *) data, offset);
+}
+
+STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags)
+{
+   return stbtt_FindMatchingFont_internal((unsigned char *) fontdata, (char *) name, flags);
+}
+
+STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2)
+{
+   return stbtt_CompareUTF8toUTF16_bigendian_internal((char *) s1, len1, (char *) s2, len2);
+}
+
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
+
+#endif // STB_TRUETYPE_IMPLEMENTATION
+
+
+// FULL VERSION HISTORY
+//
+//   1.25 (2021-07-11) many fixes
+//   1.24 (2020-02-05) fix warning
+//   1.23 (2020-02-02) query SVG data for glyphs; query whole kerning table (but only kern not GPOS)
+//   1.22 (2019-08-11) minimize missing-glyph duplication; fix kerning if both 'GPOS' and 'kern' are defined
+//   1.21 (2019-02-25) fix warning
+//   1.20 (2019-02-07) PackFontRange skips missing codepoints; GetScaleFontVMetrics()
+//   1.19 (2018-02-11) OpenType GPOS kerning (horizontal only), STBTT_fmod
+//   1.18 (2018-01-29) add missing function
+//   1.17 (2017-07-23) make more arguments const; doc fix
+//   1.16 (2017-07-12) SDF support
+//   1.15 (2017-03-03) make more arguments const
+//   1.14 (2017-01-16) num-fonts-in-TTC function
+//   1.13 (2017-01-02) support OpenType fonts, certain Apple fonts
+//   1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual
+//   1.11 (2016-04-02) fix unused-variable warning
+//   1.10 (2016-04-02) allow user-defined fabs() replacement
+//                     fix memory leak if fontsize=0.0
+//                     fix warning from duplicate typedef
+//   1.09 (2016-01-16) warning fix; avoid crash on outofmem; use alloc userdata for PackFontRanges
+//   1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges
+//   1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints;
+//                     allow PackFontRanges to pack and render in separate phases;
+//                     fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?);
+//                     fixed an assert() bug in the new rasterizer
+//                     replace assert() with STBTT_assert() in new rasterizer
+//   1.06 (2015-07-14) performance improvements (~35% faster on x86 and x64 on test machine)
+//                     also more precise AA rasterizer, except if shapes overlap
+//                     remove need for STBTT_sort
+//   1.05 (2015-04-15) fix misplaced definitions for STBTT_STATIC
+//   1.04 (2015-04-15) typo in example
+//   1.03 (2015-04-12) STBTT_STATIC, fix memory leak in new packing, various fixes
+//   1.02 (2014-12-10) fix various warnings & compile issues w/ stb_rect_pack, C++
+//   1.01 (2014-12-08) fix subpixel position when oversampling to exactly match
+//                        non-oversampled; STBTT_POINT_SIZE for packed case only
+//   1.00 (2014-12-06) add new PackBegin etc. API, w/ support for oversampling
+//   0.99 (2014-09-18) fix multiple bugs with subpixel rendering (ryg)
+//   0.9  (2014-08-07) support certain mac/iOS fonts without an MS platformID
+//   0.8b (2014-07-07) fix a warning
+//   0.8  (2014-05-25) fix a few more warnings
+//   0.7  (2013-09-25) bugfix: subpixel glyph bug fixed in 0.5 had come back
+//   0.6c (2012-07-24) improve documentation
+//   0.6b (2012-07-20) fix a few more warnings
+//   0.6  (2012-07-17) fix warnings; added stbtt_ScaleForMappingEmToPixels,
+//                        stbtt_GetFontBoundingBox, stbtt_IsGlyphEmpty
+//   0.5  (2011-12-09) bugfixes:
+//                        subpixel glyph renderer computed wrong bounding box
+//                        first vertex of shape can be off-curve (FreeSans)
+//   0.4b (2011-12-03) fixed an error in the font baking example
+//   0.4  (2011-12-01) kerning, subpixel rendering (tor)
+//                    bugfixes for:
+//                        codepoint-to-glyph conversion using table fmt=12
+//                        codepoint-to-glyph conversion using table fmt=4
+//                        stbtt_GetBakedQuad with non-square texture (Zer)
+//                    updated Hello World! sample to use kerning and subpixel
+//                    fixed some warnings
+//   0.3  (2009-06-24) cmap fmt=12, compound shapes (MM)
+//                    userdata, malloc-from-userdata, non-zero fill (stb)
+//   0.2  (2009-03-11) Fix unsigned/signed char warnings
+//   0.1  (2009-03-09) First public release
+//
+
+/*
+------------------------------------------------------------------------------
+This software is available under 2 licenses -- choose whichever you prefer.
+------------------------------------------------------------------------------
+ALTERNATIVE A - MIT License
+Copyright (c) 2017 Sean Barrett
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+------------------------------------------------------------------------------
+ALTERNATIVE B - Public Domain (www.unlicense.org)
+This is free and unencumbered software released into the public domain.
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
+software, either in source code form or as a compiled binary, for any purpose,
+commercial or non-commercial, and by any means.
+In jurisdictions that recognize copyright laws, the author or authors of this
+software dedicate any and all copyright interest in the software to the public
+domain. We make this dedication for the benefit of the public at large and to
+the detriment of our heirs and successors. We intend this dedication to be an
+overt act of relinquishment in perpetuity of all present and future rights to
+this software under copyright law.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+------------------------------------------------------------------------------
+*/
diff --git a/include/types.h b/include/types.h
new file mode 100644
index 0000000..1dc2158
--- /dev/null
+++ b/include/types.h
@@ -0,0 +1,194 @@
+#ifndef ECEX_TYPES_H
+#define ECEX_TYPES_H
+
+#include <stddef.h>
+
+typedef struct ecex ecex_t;
+typedef struct buffer buffer_t;
+typedef struct ecex_window ecex_window_t;
+
+typedef int (*ecex_command_fn)(ecex_t *ed);
+typedef int (*ecex_interactive_line_fn)(ecex_t *ed, buffer_t *buffer, size_t line, const char *payload, void *userdata);
+typedef const char *(*ecex_clipboard_get_fn)(void *userdata);
+typedef void (*ecex_clipboard_set_fn)(void *userdata, const char *text);
+
+typedef enum ecex_prompt_request {
+    ECEX_PROMPT_NONE = 0,
+    ECEX_PROMPT_FIND_FILE,
+    ECEX_PROMPT_WRITE_FILE,
+    ECEX_PROMPT_EVAL_FILE,
+    ECEX_PROMPT_SWITCH_BUFFER,
+    ECEX_PROMPT_KILL_BUFFER,
+    ECEX_PROMPT_COMPILE,
+    ECEX_PROMPT_GREP,
+    ECEX_PROMPT_ISEARCH_FORWARD,
+    ECEX_PROMPT_ISEARCH_BACKWARD,
+} ecex_prompt_request_t;
+
+typedef struct ecex_undo_entry {
+    char *data;
+    size_t len;
+    size_t point;
+    size_t mark;
+    int mark_active;
+} ecex_undo_entry_t;
+
+typedef struct ecex_color {
+    float r;
+    float g;
+    float b;
+} ecex_color_t;
+
+typedef struct ecex_theme {
+    char *font_path;
+    float font_size;
+
+    ecex_color_t bg;
+    ecex_color_t fg;
+
+    ecex_color_t status_bg;
+    ecex_color_t status_fg;
+    ecex_color_t status_border;
+
+    ecex_color_t cursor;
+    ecex_color_t region_bg;
+    ecex_color_t minibuffer_bg;
+    ecex_color_t minibuffer_fg;
+
+    ecex_color_t completion_fg;
+    int completion_enabled;
+
+    ecex_color_t interactive_highlight_bg;
+    ecex_color_t interactive_highlight_fg;
+    ecex_color_t current_line_bg;
+    ecex_color_t search_bg;
+    int line_numbers_enabled;
+    int current_line_enabled;
+} ecex_theme_t;
+
+struct buffer {
+    char *name;
+    char *path;
+
+    char *data;
+    size_t len;
+    size_t cap;
+
+    size_t point;
+    size_t mark;
+    int mark_active;
+
+    size_t scroll_line;
+    size_t scroll_col;
+
+    int modified;
+    int read_only;
+
+    int major_mode;
+
+    ecex_undo_entry_t *undo_stack;
+    size_t undo_count;
+    size_t undo_cap;
+    ecex_undo_entry_t *redo_stack;
+    size_t redo_count;
+    size_t redo_cap;
+    int undo_disabled;
+
+    int interactive;
+    struct ecex_interactive_line_action *interactive_actions;
+    size_t interactive_action_cap;
+    size_t interactive_action_count;
+};
+
+typedef struct ecex_interactive_line_action {
+    size_t line;
+    ecex_interactive_line_fn fn;
+    char *payload;
+    void *userdata;
+} ecex_interactive_line_action_t;
+
+typedef struct ecex_command {
+    char *name;
+    ecex_command_fn fn;
+} ecex_command_t;
+
+typedef struct ecex_keybind {
+    char *key;
+    char *command;
+} ecex_keybind_t;
+
+typedef struct ecex_mode_keybind {
+    int mode;
+    char *key;
+    char *command;
+} ecex_mode_keybind_t;
+
+typedef struct ecex_major_mode {
+    int id;
+    char *name;
+} ecex_major_mode_t;
+
+struct ecex_window {
+    buffer_t *buffer;
+    float x;
+    float y;
+    float w;
+    float h;
+};
+
+struct ecex {
+    buffer_t **buffers;
+    size_t buffer_cap;
+    size_t buffer_count;
+
+    size_t current_buffer_index;
+    buffer_t *current_buffer;
+
+    ecex_window_t *windows;
+    size_t window_cap;
+    size_t window_count;
+    size_t current_window_index;
+
+    void **jit_modules;
+    size_t jit_module_cap;
+    size_t jit_module_count;
+
+    ecex_command_t *commands;
+    size_t command_cap;
+    size_t command_count;
+
+    ecex_keybind_t *keybinds;
+    size_t keybind_cap;
+    size_t keybind_count;
+
+    ecex_mode_keybind_t *mode_keybinds;
+    size_t mode_keybind_cap;
+    size_t mode_keybind_count;
+
+    ecex_major_mode_t *major_modes;
+    size_t major_mode_cap;
+    size_t major_mode_count;
+    int next_major_mode_id;
+
+    char *last_eval_source;
+    char *last_eval_filename;
+    int last_eval_wrap_as_statements;
+
+    char *last_compile_command;
+    char *last_grep_command;
+
+    ecex_prompt_request_t prompt_request;
+    char prompt_message[128];
+
+    char *config_path;
+
+    ecex_clipboard_get_fn clipboard_get;
+    ecex_clipboard_set_fn clipboard_set;
+    void *clipboard_userdata;
+
+    int should_quit;
+
+    ecex_theme_t theme;
+};
+
+#endif
diff --git a/include/util.h b/include/util.h
new file mode 100644
index 0000000..9c206fb
--- /dev/null
+++ b/include/util.h
@@ -0,0 +1,10 @@
+#ifndef ECEX_UTIL_H
+#define ECEX_UTIL_H
+
+#include <stddef.h>
+
+int ecex_file_exists(const char *path);
+char *ecex_read_entire_file(const char *path, size_t *out_size);
+char *ecex_strdup(const char *s);
+
+#endif
diff --git a/manifest.scm b/manifest.scm
new file mode 100644
index 0000000..ede2f2a
--- /dev/null
+++ b/manifest.scm
@@ -0,0 +1,20 @@
+(specifications->manifest
+ '("clang-toolchain"
+   "make"
+   "pkg-config"
+   "glfw"
+   "mesa"
+   "glu"
+   "font-dejavu"
+   "libx11"
+   "libxrandr"
+   "libxinerama"
+   "libxcursor"
+   "libxi"
+   "libxxf86vm"
+   "glibc"
+   "coreutils"
+   "grep"
+   "sed"
+   "gawk"
+   "bash"))
diff --git a/src/app.c b/src/app.c
new file mode 100644
index 0000000..3ae368c
--- /dev/null
+++ b/src/app.c
@@ -0,0 +1,1578 @@
+#include "app.h"
+#include "common.h"
+
+#include <dirent.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+
+void app_message(app_t *app, const char *msg) {
+    if (!app || !msg) return;
+
+    snprintf(app->message, sizeof(app->message), "%s", msg);
+    app->dirty = 1;
+}
+
+static const char *app_clipboard_get(void *userdata) {
+    app_t *app = userdata;
+    if (!app || !app->window) return NULL;
+    return glfwGetClipboardString(app->window);
+}
+
+static void app_clipboard_set(void *userdata, const char *text) {
+    app_t *app = userdata;
+    if (!app || !app->window || !text) return;
+    glfwSetClipboardString(app->window, text);
+}
+
+static void app_reset_completion(app_t *app) {
+    if (!app) return;
+
+    app->completion_active = 0;
+    app->completion_query[0] = '\0';
+    app->completion_index = 0;
+    app->completion_count = 0;
+}
+
+static void app_set_minibuffer(app_t *app, const char *text) {
+    if (!app || !text) return;
+
+    snprintf(app->minibuffer, sizeof(app->minibuffer), "%s", text);
+    app->minibuffer_len = strlen(app->minibuffer);
+    app->dirty = 1;
+}
+
+static void app_reset_prompt_completion(app_t *app) {
+    if (!app) return;
+
+    app->prompt_completion_active = 0;
+    app->prompt_completion_query[0] = '\0';
+    app->prompt_completion_index = 0;
+    app->prompt_completion_count = 0;
+}
+
+static void app_set_prompt_input(app_t *app, const char *text) {
+    if (!app || !text) return;
+
+    snprintf(app->prompt_input, sizeof(app->prompt_input), "%s", text);
+    app->prompt_input_len = strlen(app->prompt_input);
+    app->dirty = 1;
+}
+
+static char *app_expand_user_path(const char *path) {
+    if (!path) return NULL;
+
+    if (path[0] != '~' || (path[1] != '\0' && path[1] != '/')) {
+        char *copy = malloc(strlen(path) + 1);
+        if (!copy) return NULL;
+        strcpy(copy, path);
+        return copy;
+    }
+
+    const char *home = getenv("HOME");
+    if (!home || !home[0]) {
+        char *copy = malloc(strlen(path) + 1);
+        if (!copy) return NULL;
+        strcpy(copy, path);
+        return copy;
+    }
+
+    size_t home_len = strlen(home);
+    size_t rest_len = strlen(path + 1);
+
+    char *expanded = malloc(home_len + rest_len + 1);
+    if (!expanded) return NULL;
+
+    memcpy(expanded, home, home_len);
+    memcpy(expanded + home_len, path + 1, rest_len + 1);
+    return expanded;
+}
+
+typedef struct command_candidate {
+    const char *name;
+    int score;
+    size_t order;
+} command_candidate_t;
+
+static int ascii_lower(int c) {
+    if (c >= 'A' && c <= 'Z') return c - 'A' + 'a';
+    return c;
+}
+
+static int ascii_strncasecmp_local(const char *a, const char *b, size_t n) {
+    for (size_t i = 0; i < n; i++) {
+        int ac = ascii_lower((unsigned char)a[i]);
+        int bc = ascii_lower((unsigned char)b[i]);
+
+        if (ac != bc || ac == '\0' || bc == '\0') {
+            return ac - bc;
+        }
+    }
+
+    return 0;
+}
+
+static int ascii_contains_ci(const char *haystack, const char *needle) {
+    if (!haystack || !needle) return 0;
+    if (needle[0] == '\0') return 1;
+
+    size_t needle_len = strlen(needle);
+
+    for (size_t i = 0; haystack[i]; i++) {
+        if (ascii_strncasecmp_local(haystack + i, needle, needle_len) == 0) {
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
+static int command_fuzzy_score(const char *candidate, const char *query) {
+    if (!candidate || !query) return -1;
+
+    if (query[0] == '\0') {
+        return 0;
+    }
+
+    int score = 0;
+    int consecutive = 0;
+    int last_match = -1;
+
+    size_t ci = 0;
+    size_t qi = 0;
+
+    while (candidate[ci] && query[qi]) {
+        char c = candidate[ci];
+        char q = query[qi];
+
+        if (c >= 'A' && c <= 'Z') c = (char)(c - 'A' + 'a');
+        if (q >= 'A' && q <= 'Z') q = (char)(q - 'A' + 'a');
+
+        if (c == q) {
+            score += 10;
+
+            if ((int)ci == last_match + 1) {
+                consecutive++;
+                score += 5 * consecutive;
+            } else {
+                consecutive = 0;
+            }
+
+            if (ci == 0) {
+                score += 20;
+            }
+
+            if (ci > 0 &&
+                (candidate[ci - 1] == '-' ||
+                 candidate[ci - 1] == '_' ||
+                 candidate[ci - 1] == ' ')) {
+                score += 15;
+            }
+
+            last_match = (int)ci;
+            qi++;
+        }
+
+        ci++;
+    }
+
+    if (query[qi] != '\0') {
+        return -1;
+    }
+
+    score -= (int)strlen(candidate);
+
+    if (strncmp(candidate, query, strlen(query)) == 0) {
+        score += 100;
+    }
+
+    if (ascii_contains_ci(candidate, query)) {
+        score += 75;
+    }
+
+    return score;
+}
+
+static int compare_command_candidates(const void *a, const void *b) {
+    const command_candidate_t *ca = (const command_candidate_t *)a;
+    const command_candidate_t *cb = (const command_candidate_t *)b;
+
+    if (ca->score != cb->score) {
+        return cb->score - ca->score;
+    }
+
+    if (ca->order < cb->order) return -1;
+    if (ca->order > cb->order) return 1;
+    return 0;
+}
+
+static command_candidate_t *collect_command_candidates(ecex_t *ed,
+                                                       const char *query,
+                                                       size_t *out_count) {
+    if (out_count) *out_count = 0;
+    if (!ed || !query || ed->command_count == 0) return NULL;
+
+    command_candidate_t *items = malloc(ed->command_count * sizeof(*items));
+    if (!items) return NULL;
+
+    size_t count = 0;
+
+    for (size_t i = 0; i < ed->command_count; i++) {
+        const char *name = ed->commands[i].name;
+        int score = command_fuzzy_score(name, query);
+
+        if (score >= 0) {
+            items[count].name = name;
+            items[count].score = score;
+            items[count].order = i;
+            count++;
+        }
+    }
+
+    if (count == 0) {
+        free(items);
+        return NULL;
+    }
+
+    qsort(items, count, sizeof(*items), compare_command_candidates);
+
+    if (out_count) *out_count = count;
+    return items;
+}
+
+static const char *command_candidate_at(ecex_t *ed,
+                                        const char *query,
+                                        size_t index,
+                                        size_t *out_count) {
+    size_t count = 0;
+    command_candidate_t *items = collect_command_candidates(ed, query, &count);
+    if (!items || count == 0) return NULL;
+
+    const char *name = items[index % count].name;
+
+    if (out_count) {
+        *out_count = count;
+    }
+
+    free(items);
+    return name;
+}
+
+typedef struct path_candidate {
+    char *path;
+    int score;
+    int is_dir;
+    size_t order;
+} path_candidate_t;
+
+static void free_path_candidates(path_candidate_t *items, size_t count) {
+    if (!items) return;
+
+    for (size_t i = 0; i < count; i++) {
+        free(items[i].path);
+    }
+
+    free(items);
+}
+
+static int compare_path_candidates(const void *a, const void *b) {
+    const path_candidate_t *pa = (const path_candidate_t *)a;
+    const path_candidate_t *pb = (const path_candidate_t *)b;
+
+    if (pa->score != pb->score) {
+        return pb->score - pa->score;
+    }
+
+    if (pa->is_dir != pb->is_dir) {
+        return pb->is_dir - pa->is_dir;
+    }
+
+    int cmp = strcmp(pa->path, pb->path);
+    if (cmp != 0) return cmp;
+
+    if (pa->order < pb->order) return -1;
+    if (pa->order > pb->order) return 1;
+    return 0;
+}
+
+static int split_path_query(const char *query,
+                            char *display_dir,
+                            size_t display_dir_size,
+                            char *fs_dir,
+                            size_t fs_dir_size,
+                            char *needle,
+                            size_t needle_size) {
+    if (!query || !display_dir || !fs_dir || !needle) return -1;
+
+    const char *last_slash = strrchr(query, '/');
+
+    if (last_slash) {
+        size_t dir_len = (size_t)(last_slash - query) + 1;
+        if (dir_len >= display_dir_size) dir_len = display_dir_size - 1;
+
+        memcpy(display_dir, query, dir_len);
+        display_dir[dir_len] = '\0';
+
+        snprintf(needle, needle_size, "%s", last_slash + 1);
+    } else {
+        display_dir[0] = '\0';
+        snprintf(needle, needle_size, "%s", query);
+    }
+
+    if (display_dir[0] == '\0') {
+        snprintf(fs_dir, fs_dir_size, ".");
+    } else {
+        char *expanded = app_expand_user_path(display_dir);
+        if (!expanded) return -1;
+
+        snprintf(fs_dir, fs_dir_size, "%s", expanded);
+        free(expanded);
+    }
+
+    return 0;
+}
+
+static char *join_display_path(const char *display_dir,
+                               const char *name,
+                               int is_dir) {
+    size_t dir_len = display_dir ? strlen(display_dir) : 0;
+    size_t name_len = name ? strlen(name) : 0;
+    size_t slash_len = is_dir ? 1 : 0;
+
+    char *out = malloc(dir_len + name_len + slash_len + 1);
+    if (!out) return NULL;
+
+    if (dir_len) memcpy(out, display_dir, dir_len);
+    if (name_len) memcpy(out + dir_len, name, name_len);
+    if (is_dir) out[dir_len + name_len] = '/';
+    out[dir_len + name_len + slash_len] = '\0';
+    return out;
+}
+
+static path_candidate_t *collect_path_candidates(const char *query,
+                                                 size_t *out_count) {
+    if (out_count) *out_count = 0;
+    if (!query) return NULL;
+
+    char display_dir[1024];
+    char fs_dir[1024];
+    char needle[512];
+
+    if (split_path_query(query,
+                         display_dir,
+                         sizeof(display_dir),
+                         fs_dir,
+                         sizeof(fs_dir),
+                         needle,
+                         sizeof(needle)) != 0) {
+        return NULL;
+    }
+
+    DIR *dir = opendir(fs_dir);
+    if (!dir) return NULL;
+
+    size_t cap = 32;
+    size_t count = 0;
+    size_t order = 0;
+    path_candidate_t *items = malloc(cap * sizeof(*items));
+    if (!items) {
+        closedir(dir);
+        return NULL;
+    }
+
+    struct dirent *entry = NULL;
+    while ((entry = readdir(dir)) != NULL) {
+        const char *name = entry->d_name;
+
+        if (strcmp(name, ".") == 0) {
+            continue;
+        }
+
+        if (name[0] == '.' && needle[0] != '.' && strcmp(name, "..") != 0) {
+            continue;
+        }
+
+        int score = command_fuzzy_score(name, needle);
+        if (score < 0) {
+            order++;
+            continue;
+        }
+
+        char fs_path[2048];
+        if (strcmp(fs_dir, ".") == 0) {
+            snprintf(fs_path, sizeof(fs_path), "%s", name);
+        } else {
+            size_t len = strlen(fs_dir);
+            snprintf(fs_path,
+                     sizeof(fs_path),
+                     "%s%s%s",
+                     fs_dir,
+                     (len > 0 && fs_dir[len - 1] == '/') ? "" : "/",
+                     name);
+        }
+
+        struct stat st;
+        int is_dir = stat(fs_path, &st) == 0 && S_ISDIR(st.st_mode);
+
+        if (count == cap) {
+            size_t new_cap = cap * 2;
+            path_candidate_t *new_items = realloc(items, new_cap * sizeof(*items));
+            if (!new_items) break;
+            items = new_items;
+            cap = new_cap;
+        }
+
+        items[count].path = join_display_path(display_dir, name, is_dir);
+        if (!items[count].path) continue;
+
+        items[count].score = score + (is_dir ? 20 : 0);
+        items[count].is_dir = is_dir;
+        items[count].order = order;
+        count++;
+        order++;
+    }
+
+    closedir(dir);
+
+    if (count == 0) {
+        free(items);
+        return NULL;
+    }
+
+    qsort(items, count, sizeof(*items), compare_path_candidates);
+
+    if (out_count) *out_count = count;
+    return items;
+}
+
+static const char *path_candidate_at(const char *query,
+                                     size_t index,
+                                     size_t *out_count) {
+    static char candidate[1024];
+
+    size_t count = 0;
+    path_candidate_t *items = collect_path_candidates(query, &count);
+    if (!items || count == 0) {
+        free_path_candidates(items, count);
+        return NULL;
+    }
+
+    snprintf(candidate, sizeof(candidate), "%s", items[index % count].path);
+
+    if (out_count) {
+        *out_count = count;
+    }
+
+    free_path_candidates(items, count);
+    return candidate;
+}
+
+static void app_update_prompt_completion_preview(app_t *app) {
+    if (!app || !app->prompt_completion_active) return;
+
+    size_t count = 0;
+    path_candidate_t *items = collect_path_candidates(app->prompt_completion_query, &count);
+    if (!items || count == 0) {
+        free_path_candidates(items, count);
+        app->prompt_completion_preview_start = 0;
+        app->prompt_completion_preview_count = 0;
+        return;
+    }
+
+    size_t max_preview = sizeof(app->prompt_completion_preview) /
+        sizeof(app->prompt_completion_preview[0]);
+
+    size_t start = 0;
+    if (app->prompt_completion_index >= max_preview) {
+        start = app->prompt_completion_index - max_preview + 1;
+    }
+
+    app->prompt_completion_preview_start = start;
+    app->prompt_completion_preview_count = 0;
+
+    for (size_t i = 0; i < max_preview && start + i < count; i++) {
+        snprintf(app->prompt_completion_preview[i],
+                 sizeof(app->prompt_completion_preview[i]),
+                 "%s",
+                 items[start + i].path);
+        app->prompt_completion_preview_count++;
+    }
+
+    free_path_candidates(items, count);
+}
+
+static void app_begin_prompt_completion(app_t *app, int direction) {
+    if (!app) return;
+
+    snprintf(app->prompt_completion_query,
+             sizeof(app->prompt_completion_query),
+             "%s",
+             app->prompt_input);
+
+    size_t count = 0;
+    path_candidate_t *items = collect_path_candidates(app->prompt_completion_query, &count);
+
+    if (!items || count == 0) {
+        free_path_candidates(items, count);
+        app_reset_prompt_completion(app);
+        app_message(app, "No file completions");
+        app->mode = APP_MODE_PROMPT;
+        return;
+    }
+
+    app->prompt_completion_active = 1;
+    app->prompt_completion_count = count;
+    app->prompt_completion_index = direction < 0 ? count - 1 : 0;
+
+    app_set_prompt_input(app, items[app->prompt_completion_index].path);
+    free_path_candidates(items, count);
+    app_update_prompt_completion_preview(app);
+}
+
+static void app_cycle_prompt_completion(app_t *app, int delta) {
+    if (!app) return;
+
+    if (!app->prompt_completion_active || app->prompt_completion_count == 0) {
+        app_begin_prompt_completion(app, delta);
+        return;
+    }
+
+    if (delta < 0) {
+        app->prompt_completion_index = app->prompt_completion_index == 0
+            ? app->prompt_completion_count - 1
+            : app->prompt_completion_index - 1;
+    } else {
+        app->prompt_completion_index =
+            (app->prompt_completion_index + 1) % app->prompt_completion_count;
+    }
+
+    size_t count = 0;
+    const char *candidate = path_candidate_at(app->prompt_completion_query,
+                                              app->prompt_completion_index,
+                                              &count);
+
+    if (!candidate || count == 0) {
+        app_reset_prompt_completion(app);
+        return;
+    }
+
+    app->prompt_completion_count = count;
+    app_set_prompt_input(app, candidate);
+    app_update_prompt_completion_preview(app);
+}
+
+static void app_begin_completion(app_t *app, int direction) {
+    if (!app) return;
+
+    snprintf(app->completion_query,
+             sizeof(app->completion_query),
+             "%s",
+             app->minibuffer);
+
+    size_t count = 0;
+    command_candidate_t *items =
+        collect_command_candidates(app->ed, app->completion_query, &count);
+
+    if (!items || count == 0) {
+        free(items);
+        app_reset_completion(app);
+        app_message(app, "No command completions");
+        app->mode = APP_MODE_MX;
+        return;
+    }
+
+    app->completion_active = 1;
+    app->completion_count = count;
+
+    if (direction < 0) {
+        app->completion_index = count - 1;
+    } else {
+        app->completion_index = 0;
+    }
+
+    app_set_minibuffer(app, items[app->completion_index].name);
+    free(items);
+}
+
+static void app_cycle_completion(app_t *app, int delta) {
+    if (!app) return;
+
+    if (!app->completion_active || app->completion_count == 0) {
+        app_begin_completion(app, delta);
+        return;
+    }
+
+    if (delta < 0) {
+        if (app->completion_index == 0) {
+            app->completion_index = app->completion_count - 1;
+        } else {
+            app->completion_index--;
+        }
+    } else {
+        app->completion_index =
+            (app->completion_index + 1) % app->completion_count;
+    }
+
+    size_t count = 0;
+    const char *candidate = command_candidate_at(app->ed,
+                                                 app->completion_query,
+                                                 app->completion_index,
+                                                 &count);
+
+    if (!candidate || count == 0) {
+        app_reset_completion(app);
+        return;
+    }
+
+    app->completion_count = count;
+    app_set_minibuffer(app, candidate);
+}
+
+static void app_enter_mx(app_t *app) {
+    app->mode = APP_MODE_MX;
+    app->minibuffer[0] = '\0';
+    app->minibuffer_len = 0;
+    app->prefix[0] = '\0';
+    app->prefix_len = 0;
+    app->message[0] = '\0';
+    app_reset_completion(app);
+    app->dirty = 1;
+}
+
+static void app_cancel_mx(app_t *app) {
+    app->mode = APP_MODE_EDIT;
+    app->minibuffer[0] = '\0';
+    app->minibuffer_len = 0;
+    app_reset_completion(app);
+    app_message(app, "Quit");
+}
+
+
+static void app_update_isearch(app_t *app) {
+    if (!app || !app->ed) return;
+    buffer_t *buf = ecex_current_buffer(app->ed);
+    if (!buf || app->isearch_len == 0) {
+        app->isearch_has_match = 0;
+        app->dirty = 1;
+        return;
+    }
+    size_t pos = 0;
+    size_t start = app->isearch_backward
+        ? (buf->point > 0 ? buf->point - 1 : buf->len)
+        : buf->point;
+    int ok = app->isearch_backward
+        ? buffer_search_backward(buf, app->isearch_query, start, &pos)
+        : buffer_search_forward(buf, app->isearch_query, start, &pos);
+    if (ok == ECEX_OK) {
+        app->isearch_match = pos;
+        app->isearch_has_match = 1;
+        buffer_set_point(buf, pos);
+        buffer_set_mark(buf, pos + strlen(app->isearch_query));
+    } else {
+        app->isearch_has_match = 0;
+    }
+    app->dirty = 1;
+}
+
+static void app_enter_isearch(app_t *app, int backward) {
+    if (!app || !app->ed) return;
+    buffer_t *buf = ecex_current_buffer(app->ed);
+    app->mode = APP_MODE_ISEARCH;
+    app->isearch_backward = backward ? 1 : 0;
+    app->isearch_query[0] = '\0';
+    app->isearch_len = 0;
+    app->isearch_origin = buf ? buf->point : 0;
+    app->isearch_match = app->isearch_origin;
+    app->isearch_has_match = 0;
+    app->prefix[0] = '\0';
+    app->prefix_len = 0;
+    app->message[0] = '\0';
+    app->dirty = 1;
+}
+
+static void app_cancel_isearch(app_t *app) {
+    if (!app || !app->ed) return;
+    buffer_t *buf = ecex_current_buffer(app->ed);
+    if (buf) {
+        buffer_set_point(buf, app->isearch_origin);
+        buffer_clear_mark(buf);
+    }
+    app->mode = APP_MODE_EDIT;
+    app_message(app, "Search cancelled");
+}
+
+static void app_finish_isearch(app_t *app) {
+    if (!app || !app->ed) return;
+    buffer_t *buf = ecex_current_buffer(app->ed);
+    if (app->isearch_len > 0) {
+        snprintf(app->last_search_query, sizeof(app->last_search_query), "%s", app->isearch_query);
+    }
+    if (buf) buffer_clear_mark(buf);
+    app->mode = APP_MODE_EDIT;
+    if (app->isearch_len > 0) app_message(app, app->isearch_has_match ? "Search done" : "Search failed");
+    app->dirty = 1;
+}
+
+static void app_enter_prompt(app_t *app,
+                             ecex_prompt_request_t kind,
+                             const char *label) {
+    if (!app) return;
+
+    app->mode = APP_MODE_PROMPT;
+    app->prompt_kind = kind;
+    snprintf(app->prompt_label,
+             sizeof(app->prompt_label),
+             "%s",
+             label ? label : "");
+    app->prompt_input[0] = '\0';
+    app->prompt_input_len = 0;
+    app_reset_prompt_completion(app);
+    app->message[0] = '\0';
+    app->dirty = 1;
+}
+
+
+static void app_reload_font_if_needed(app_t *app) {
+    if (!app || !app->ed) return;
+
+    const char *path = NULL;
+    if (app->ed->theme.font_path && app->ed->theme.font_path[0]) {
+        path = app->ed->theme.font_path;
+    } else if (app->font_path[0]) {
+        path = app->font_path;
+    } else {
+        path = font_choose_path(NULL);
+    }
+
+    if (!path || !path[0]) return;
+
+    float size = app->ed->theme.font_size;
+    int same_path = app->font_path[0] && strcmp(app->font_path, path) == 0;
+    int same_size = app->font.size_px == size;
+
+    if (same_path && same_size) return;
+
+    font_t new_font;
+    if (font_load(&new_font, path, size) != 0) {
+        char msg[ECEX_MINIBUFFER_SIZE];
+        snprintf(msg, sizeof(msg), "Failed to reload font: %s", path);
+        app_message(app, msg);
+        return;
+    }
+
+    font_free(&app->font);
+    app->font = new_font;
+    snprintf(app->font_path, sizeof(app->font_path), "%s", path);
+    app->dirty = 1;
+}
+
+static int app_handle_prompt_request(app_t *app) {
+    if (!app || !app->ed) return 0;
+
+    if (app->ed->prompt_request == ECEX_PROMPT_NONE) {
+        return 0;
+    }
+
+    ecex_prompt_request_t request = app->ed->prompt_request;
+    char label[sizeof(app->ed->prompt_message)];
+    snprintf(label, sizeof(label), "%s", app->ed->prompt_message);
+
+    ecex_clear_prompt_request(app->ed);
+    if (request == ECEX_PROMPT_ISEARCH_FORWARD) {
+        app_enter_isearch(app, 0);
+    } else if (request == ECEX_PROMPT_ISEARCH_BACKWARD) {
+        app_enter_isearch(app, 1);
+    } else {
+        app_enter_prompt(app, request, label);
+    }
+    return 1;
+}
+
+static int app_execute_command(app_t *app, const char *command) {
+    if (!app || !app->ed || !command) return -1;
+
+    int result = ecex_execute_command(app->ed, command);
+    if (result == 0) {
+        app_reload_font_if_needed(app);
+        app_handle_prompt_request(app);
+    }
+
+    if (app->ed->should_quit && app->window) {
+        glfwSetWindowShouldClose(app->window, GLFW_TRUE);
+        glfwPostEmptyEvent();
+    }
+
+    app->dirty = 1;
+    return result;
+}
+
+static void app_cancel_prompt(app_t *app) {
+    if (!app) return;
+
+    app->mode = APP_MODE_EDIT;
+    app->prompt_kind = ECEX_PROMPT_NONE;
+    app->prompt_label[0] = '\0';
+    app->prompt_input[0] = '\0';
+    app->prompt_input_len = 0;
+    app_reset_prompt_completion(app);
+    app_message(app, "Prompt cancelled");
+}
+
+static void app_submit_prompt(app_t *app) {
+    if (!app || !app->ed) return;
+
+    if (app->prompt_input_len == 0 && app->prompt_kind != ECEX_PROMPT_COMPILE) {
+        app_cancel_prompt(app);
+        return;
+    }
+
+    char input[sizeof(app->prompt_input)];
+    snprintf(input, sizeof(input), "%s", app->prompt_input);
+
+    ecex_prompt_request_t kind = app->prompt_kind;
+    app->mode = APP_MODE_EDIT;
+    app->prompt_kind = ECEX_PROMPT_NONE;
+    app->prompt_label[0] = '\0';
+    app->prompt_input[0] = '\0';
+    app->prompt_input_len = 0;
+
+    char *expanded_input = app_expand_user_path(input);
+    const char *path = expanded_input ? expanded_input : input;
+
+    int result = -1;
+    const char *verb = "Prompt";
+
+    switch (kind) {
+        case ECEX_PROMPT_FIND_FILE:
+            result = ecex_find_file(app->ed, path);
+            verb = "Opened";
+            break;
+
+        case ECEX_PROMPT_WRITE_FILE:
+            result = ecex_write_current_buffer(app->ed, path);
+            verb = "Wrote";
+            break;
+
+        case ECEX_PROMPT_EVAL_FILE:
+            result = ecex_eval_file(app->ed, path);
+            verb = "Evaluated";
+            break;
+
+        case ECEX_PROMPT_SWITCH_BUFFER:
+            result = ecex_switch_buffer(app->ed, input);
+            verb = "Switched";
+            break;
+
+        case ECEX_PROMPT_KILL_BUFFER:
+            result = ecex_kill_buffer(app->ed, input);
+            verb = "Killed";
+            break;
+
+        case ECEX_PROMPT_COMPILE:
+            result = ecex_compile(app->ed, input[0] ? input : "make");
+            verb = "Compiled";
+            break;
+
+        case ECEX_PROMPT_GREP:
+            result = ecex_grep(app->ed, input);
+            verb = "Grep";
+            break;
+
+        case ECEX_PROMPT_NONE:
+        default:
+            result = -1;
+            break;
+    }
+
+    if (result == 0) {
+        app_reload_font_if_needed(app);
+    }
+
+    char msg[ECEX_MINIBUFFER_SIZE];
+    if (result == 0) {
+        snprintf(msg, sizeof(msg), "%s: %s", verb, path);
+    } else {
+        snprintf(msg, sizeof(msg), "Failed: %s", path);
+    }
+
+    free(expanded_input);
+    app_reset_prompt_completion(app);
+    app_message(app, msg);
+}
+
+static void app_execute_mx(app_t *app) {
+    if (!app) return;
+
+    if (app->minibuffer_len == 0) {
+        app_cancel_mx(app);
+        return;
+    }
+
+    char command[ECEX_MINIBUFFER_SIZE];
+    snprintf(command, sizeof(command), "%s", app->minibuffer);
+
+    app->mode = APP_MODE_EDIT;
+    app->minibuffer[0] = '\0';
+    app->minibuffer_len = 0;
+    app_reset_completion(app);
+
+    if (app_execute_command(app, command) == 0) {
+        if (app->mode == APP_MODE_EDIT) {
+            char msg[ECEX_MINIBUFFER_SIZE];
+            snprintf(msg, sizeof(msg), "Executed: %s", command);
+            app_message(app, msg);
+        }
+    } else {
+        char msg[ECEX_MINIBUFFER_SIZE];
+        snprintf(msg, sizeof(msg), "No such command: %s", command);
+        app_message(app, msg);
+    }
+
+    if (app->ed->should_quit) {
+        glfwSetWindowShouldClose(app->window, GLFW_TRUE);
+        glfwPostEmptyEvent();
+    }
+
+    app->dirty = 1;
+}
+
+static void app_complete_mx(app_t *app) {
+    if (!app) return;
+
+    if (app->completion_active) {
+        app_cycle_completion(app, 1);
+    } else {
+        app_begin_completion(app, 1);
+    }
+}
+
+static void app_enter_prefix(app_t *app, const char *first_key) {
+    if (!app || !first_key) return;
+
+    app->mode = APP_MODE_PREFIX;
+    app->minibuffer[0] = '\0';
+    app->minibuffer_len = 0;
+    app_reset_completion(app);
+
+    snprintf(app->prefix, sizeof(app->prefix), "%s", first_key);
+    app->prefix_len = strlen(app->prefix);
+
+    app->message[0] = '\0';
+    app->dirty = 1;
+}
+
+static void app_cancel_prefix(app_t *app) {
+    if (!app) return;
+
+    app->mode = APP_MODE_EDIT;
+    app->prefix[0] = '\0';
+    app->prefix_len = 0;
+
+    app_message(app, "Prefix cancelled");
+}
+
+static int app_append_prefix_key(app_t *app, const char *key_name) {
+    if (!app || !key_name) return -1;
+
+    size_t key_len = strlen(key_name);
+
+    if (app->prefix_len + 1 + key_len + 1 >= sizeof(app->prefix)) {
+        app_cancel_prefix(app);
+        return -1;
+    }
+
+    app->prefix[app->prefix_len++] = ' ';
+    memcpy(app->prefix + app->prefix_len, key_name, key_len + 1);
+    app->prefix_len += key_len;
+
+    return 0;
+}
+
+static int key_sequence_has_prefix(app_t *app, const char *prefix) {
+    if (!app || !app->ed || !prefix) return 0;
+    return ecex_key_sequence_has_prefix_for_buffer(app->ed,
+                                                   ecex_current_buffer(app->ed),
+                                                   prefix);
+}
+
+static void app_finish_prefix(app_t *app) {
+    if (!app) return;
+
+    const char *command = ecex_lookup_key_for_buffer(app->ed, ecex_current_buffer(app->ed), app->prefix);
+
+    if (command) {
+        if (app_execute_command(app, command) == 0) {
+            if (app->mode == APP_MODE_EDIT) {
+                char msg[ECEX_MINIBUFFER_SIZE];
+                snprintf(msg, sizeof(msg), "Executed: %s", command);
+                app_message(app, msg);
+            }
+        } else {
+            char msg[ECEX_MINIBUFFER_SIZE];
+            snprintf(msg, sizeof(msg), "Command failed: %s", command);
+            app_message(app, msg);
+        }
+
+        if (app->ed->should_quit) {
+            glfwSetWindowShouldClose(app->window, GLFW_TRUE);
+            glfwPostEmptyEvent();
+        }
+
+        if (app->mode != APP_MODE_PROMPT) {
+            app->mode = APP_MODE_EDIT;
+        }
+        app->prefix[0] = '\0';
+        app->prefix_len = 0;
+        app->dirty = 1;
+        return;
+    }
+
+    if (key_sequence_has_prefix(app, app->prefix)) {
+        app->dirty = 1;
+        return;
+    }
+
+    char msg[ECEX_MINIBUFFER_SIZE];
+    snprintf(msg, sizeof(msg), "Undefined key: %s", app->prefix);
+
+    app->mode = APP_MODE_EDIT;
+    app->prefix[0] = '\0';
+    app->prefix_len = 0;
+
+    app_message(app, msg);
+}
+
+
+static float app_mono_cell_width(app_t *app) {
+    float w = text_width(&app->font, "M");
+    return w > 1.0f ? w : app->font.size_px * 0.6f;
+}
+
+static float app_status_height(app_t *app) {
+    float line_h = app->font.line_height > 1.0f ? app->font.line_height : app->font.size_px * 1.2f;
+    float pad_y = app->font.size_px * 0.35f;
+    if (pad_y < 4.0f) pad_y = 4.0f;
+    return line_h + pad_y * 2.0f;
+}
+
+static float app_minibuffer_height(app_t *app) { return app_status_height(app); }
+
+static int app_minibuffer_visible(app_t *app) {
+    return app->mode == APP_MODE_MX || app->mode == APP_MODE_PREFIX ||
+           app->mode == APP_MODE_PROMPT || app->mode == APP_MODE_ISEARCH ||
+           app->message[0] != '\0';
+}
+
+static size_t app_offset_for_line(buffer_t *buf, size_t target_line) {
+    if (!buf || target_line == 0) return 0;
+    size_t line = 0;
+    for (size_t i = 0; i < buf->len; i++) {
+        if (buf->data[i] == '\n') {
+            line++;
+            if (line == target_line) return i + 1;
+        }
+    }
+    return buf->len;
+}
+
+static int app_focus_window_at(app_t *app, double px, double py) {
+    if (!app || !app->ed || app->ed->window_count == 0) return -1;
+    float editor_h = (float)app->height - app_status_height(app);
+    if (app_minibuffer_visible(app)) editor_h -= app_minibuffer_height(app);
+    if (editor_h < 1.0f) editor_h = 1.0f;
+    for (size_t i = 0; i < app->ed->window_count; i++) {
+        ecex_window_t *w = &app->ed->windows[i];
+        float x = w->x * (float)app->width;
+        float y = w->y * editor_h;
+        float ww = w->w * (float)app->width;
+        float hh = w->h * editor_h;
+        if (px >= x && px < x + ww && py >= y && py < y + hh) {
+            app->ed->current_window_index = i;
+            ecex_sync_current_buffer(app->ed);
+            return (int)i;
+        }
+    }
+    return -1;
+}
+
+static void app_move_point_to_pixel(app_t *app, double px, double py) {
+    int wi = app_focus_window_at(app, px, py);
+    if (wi < 0) return;
+    ecex_window_t *w = &app->ed->windows[wi];
+    buffer_t *buf = w->buffer;
+    if (!buf) return;
+    float editor_h = (float)app->height - app_status_height(app);
+    if (app_minibuffer_visible(app)) editor_h -= app_minibuffer_height(app);
+    float wx = w->x * (float)app->width;
+    float wy = w->y * editor_h;
+    float pad_x = app->font.size_px * 0.75f; if (pad_x < 8.0f) pad_x = 8.0f;
+    float pad_y = app->font.size_px * 0.35f; if (pad_y < 4.0f) pad_y = 4.0f;
+    size_t row = py > wy + pad_y ? (size_t)((py - wy - pad_y) / app->font.line_height) : 0;
+    size_t col = px > wx + pad_x ? (size_t)((px - wx - pad_x) / app_mono_cell_width(app)) : 0;
+    size_t line = buf->scroll_line + row;
+    size_t start = app_offset_for_line(buf, line);
+    size_t end = buffer_line_end_at(buf, start);
+    buffer_set_point(buf, start + ECEX_MIN(col + buf->scroll_col, end - start));
+    app->dirty = 1;
+}
+
+static void mouse_button_callback(GLFWwindow *window, int button, int action, int mods) {
+    (void)mods;
+    if (button != GLFW_MOUSE_BUTTON_LEFT || action != GLFW_PRESS) return;
+    app_t *app = glfwGetWindowUserPointer(window);
+    if (!app) return;
+    glfwGetFramebufferSize(window, &app->width, &app->height);
+    double x = 0.0, y = 0.0;
+    glfwGetCursorPos(window, &x, &y);
+    app_move_point_to_pixel(app, x, y);
+}
+
+static void scroll_callback(GLFWwindow *window, double xoffset, double yoffset) {
+    (void)xoffset;
+    app_t *app = glfwGetWindowUserPointer(window);
+    if (!app || !app->ed) return;
+    buffer_t *buf = ecex_current_buffer(app->ed);
+    if (!buf) return;
+    if (yoffset < 0.0) buf->scroll_line += 3;
+    else if (yoffset > 0.0) buf->scroll_line = buf->scroll_line > 3 ? buf->scroll_line - 3 : 0;
+    app->dirty = 1;
+}
+
+static void mark_dirty(GLFWwindow *window) {
+    app_t *app = glfwGetWindowUserPointer(window);
+    if (app) {
+        app->dirty = 1;
+    }
+}
+
+static void framebuffer_size_callback(GLFWwindow *window, int width, int height) {
+    (void)width;
+    (void)height;
+
+    mark_dirty(window);
+}
+
+static void window_refresh_callback(GLFWwindow *window) {
+    mark_dirty(window);
+}
+
+static const char *key_name_for_special(int key) {
+    switch (key) {
+        case GLFW_KEY_F1: return "F1";
+        case GLFW_KEY_F2: return "F2";
+        case GLFW_KEY_F3: return "F3";
+        case GLFW_KEY_F4: return "F4";
+        case GLFW_KEY_F5: return "F5";
+        case GLFW_KEY_LEFT: return "LEFT";
+        case GLFW_KEY_RIGHT: return "RIGHT";
+        case GLFW_KEY_UP: return "UP";
+        case GLFW_KEY_DOWN: return "DOWN";
+        case GLFW_KEY_ENTER: return "ENTER";
+        case GLFW_KEY_BACKSPACE: return "BACKSPACE";
+        case GLFW_KEY_DELETE: return "DELETE";
+        case GLFW_KEY_TAB: return "TAB";
+        case GLFW_KEY_SPACE: return "SPC";
+        case GLFW_KEY_ESCAPE: return "ESC";
+        case GLFW_KEY_HOME: return "HOME";
+        case GLFW_KEY_END: return "END";
+        case GLFW_KEY_PAGE_UP: return "PAGEUP";
+        case GLFW_KEY_PAGE_DOWN: return "PAGEDOWN";
+        default: return NULL;
+    }
+}
+
+static int layout_key_name(int key,
+                           int scancode,
+                           char *out,
+                           size_t out_size) {
+    if (!out || out_size == 0) return -1;
+
+    out[0] = '\0';
+
+    const char *special = key_name_for_special(key);
+    if (special) {
+        snprintf(out, out_size, "%s", special);
+        return 0;
+    }
+
+    const char *name = glfwGetKeyName(key, scancode);
+    if (!name || !name[0]) return -1;
+
+    if (name[1] != '\0') return -1;
+
+    char c = name[0];
+    if (c >= 'A' && c <= 'Z') {
+        c = (char)(c - 'A' + 'a');
+    }
+
+    out[0] = c;
+    out[1] = '\0';
+    return 0;
+}
+
+static int key_event_to_string(int key,
+                               int scancode,
+                               int mods,
+                               char *out,
+                               size_t out_size) {
+    if (!out || out_size == 0) return -1;
+
+    out[0] = '\0';
+
+    char base[32];
+    if (layout_key_name(key, scancode, base, sizeof(base)) != 0) {
+        return -1;
+    }
+
+    char prefix[32];
+    prefix[0] = '\0';
+
+    if (mods & GLFW_MOD_CONTROL) {
+        strncat(prefix, "C-", sizeof(prefix) - strlen(prefix) - 1);
+    }
+
+    if (mods & GLFW_MOD_ALT) {
+        strncat(prefix, "M-", sizeof(prefix) - strlen(prefix) - 1);
+    }
+
+    if (mods & GLFW_MOD_SUPER) {
+        strncat(prefix, "S-", sizeof(prefix) - strlen(prefix) - 1);
+    }
+
+    snprintf(out, out_size, "%s%s", prefix, base);
+    return 0;
+}
+
+static int is_layout_char_key(int key,
+                              int scancode,
+                              char wanted) {
+    char name[32];
+
+    if (layout_key_name(key, scancode, name, sizeof(name)) != 0) {
+        return 0;
+    }
+
+    if (wanted >= 'A' && wanted <= 'Z') {
+        wanted = (char)(wanted - 'A' + 'a');
+    }
+
+    return name[0] == wanted && name[1] == '\0';
+}
+
+static int key_produces_text(int key, int scancode) {
+    if (key_name_for_special(key)) {
+        return 0;
+    }
+
+    const char *name = glfwGetKeyName(key, scancode);
+    return name && name[0] && name[1] == '\0';
+}
+
+static void try_execute_keybind(app_t *app, const char *key_name) {
+    const char *command = ecex_lookup_key_for_buffer(app->ed, ecex_current_buffer(app->ed), key_name);
+    if (!command) return;
+
+    if (app_execute_command(app, command) == 0) {
+        app->dirty = 1;
+    } else {
+        char msg[ECEX_MINIBUFFER_SIZE];
+        snprintf(msg, sizeof(msg), "Bad keybind: %s -> %s", key_name, command);
+        app_message(app, msg);
+    }
+
+    if (app->ed->should_quit) {
+        glfwSetWindowShouldClose(app->window, GLFW_TRUE);
+        glfwPostEmptyEvent();
+    }
+}
+
+static void char_callback(GLFWwindow *window, unsigned int codepoint) {
+    app_t *app = glfwGetWindowUserPointer(window);
+    if (!app || !app->ed) return;
+
+    if (app->suppress_next_char) {
+        app->suppress_next_char = 0;
+        return;
+    }
+
+    if (app->mode == APP_MODE_EDIT) {
+        if ((app->current_mods & GLFW_MOD_ALT) && codepoint == 'x') {
+            app_enter_mx(app);
+            return;
+        }
+    }
+
+    if (app->mode == APP_MODE_MX) {
+        if (codepoint >= 32 && codepoint <= 126) {
+            if (app->minibuffer_len + 1 < sizeof(app->minibuffer)) {
+                app_reset_completion(app);
+                app->minibuffer[app->minibuffer_len++] = (char)codepoint;
+                app->minibuffer[app->minibuffer_len] = '\0';
+                app->dirty = 1;
+            }
+        }
+        return;
+    }
+
+    if (app->mode == APP_MODE_ISEARCH) {
+        if (codepoint >= 32 && codepoint <= 126) {
+            if (app->isearch_len + 1 < sizeof(app->isearch_query)) {
+                app->isearch_query[app->isearch_len++] = (char)codepoint;
+                app->isearch_query[app->isearch_len] = '\0';
+                app_update_isearch(app);
+            }
+        }
+        return;
+    }
+
+    if (app->mode == APP_MODE_PROMPT) {
+        if (codepoint >= 32 && codepoint <= 126) {
+            if (app->prompt_input_len + 1 < sizeof(app->prompt_input)) {
+                app->prompt_input[app->prompt_input_len++] = (char)codepoint;
+                app->prompt_input[app->prompt_input_len] = '\0';
+                app->dirty = 1;
+            }
+        }
+        return;
+    }
+
+    if (app->mode == APP_MODE_PREFIX) {
+        return;
+    }
+
+    buffer_t *buf = ecex_current_buffer(app->ed);
+    if (!buf) return;
+
+    if (buffer_is_interactive(buf)) {
+        return;
+    }
+
+    if (codepoint >= 32 && codepoint <= 126) {
+        buffer_insert_char(buf, (char)codepoint);
+        app->message[0] = '\0';
+        app->dirty = 1;
+    }
+}
+
+static void key_callback(GLFWwindow *window,
+                         int key,
+                         int scancode,
+                         int action,
+                         int mods) {
+    if (action != GLFW_PRESS && action != GLFW_REPEAT) {
+        return;
+    }
+
+    app_t *app = glfwGetWindowUserPointer(window);
+    if (!app || !app->ed) return;
+
+    app->current_mods = mods;
+
+    if (app->mode == APP_MODE_EDIT && key == GLFW_KEY_F1) {
+        app_enter_mx(app);
+        return;
+    }
+
+    if (app->mode == APP_MODE_EDIT &&
+        (mods & GLFW_MOD_ALT) &&
+        is_layout_char_key(key, scancode, 'g')) {
+        app_enter_prefix(app, "M-g");
+        return;
+    }
+
+    if (app->mode == APP_MODE_EDIT &&
+        (mods & GLFW_MOD_CONTROL) &&
+        is_layout_char_key(key, scancode, 'x')) {
+        app_enter_prefix(app, "C-x");
+        return;
+    }
+
+    if (app->mode == APP_MODE_MX) {
+        switch (key) {
+            case GLFW_KEY_ESCAPE:
+                app_cancel_mx(app);
+                return;
+
+            case GLFW_KEY_ENTER:
+                app_execute_mx(app);
+                return;
+
+            case GLFW_KEY_TAB:
+                app_complete_mx(app);
+                return;
+
+            case GLFW_KEY_DOWN:
+                app_cycle_completion(app, 1);
+                return;
+
+            case GLFW_KEY_UP:
+                app_cycle_completion(app, -1);
+                return;
+
+            case GLFW_KEY_BACKSPACE:
+                if (app->minibuffer_len > 0) {
+                    app_reset_completion(app);
+                    app->minibuffer_len--;
+                    app->minibuffer[app->minibuffer_len] = '\0';
+                    app->dirty = 1;
+                }
+                return;
+
+            default:
+                return;
+        }
+    }
+
+    if (app->mode == APP_MODE_ISEARCH) {
+        switch (key) {
+            case GLFW_KEY_ESCAPE:
+                app_cancel_isearch(app);
+                return;
+            case GLFW_KEY_ENTER:
+                app_finish_isearch(app);
+                return;
+            case GLFW_KEY_BACKSPACE:
+                if (app->isearch_len > 0) {
+                    app->isearch_len--;
+                    app->isearch_query[app->isearch_len] = '\0';
+                    buffer_t *buf = ecex_current_buffer(app->ed);
+                    if (buf) {
+                        buffer_set_point(buf, app->isearch_origin);
+                        buffer_clear_mark(buf);
+                    }
+                    app_update_isearch(app);
+                }
+                return;
+            default:
+                if ((mods & GLFW_MOD_CONTROL) && is_layout_char_key(key, scancode, 's')) {
+                    app->isearch_backward = 0;
+                    app_update_isearch(app);
+                    return;
+                }
+                if ((mods & GLFW_MOD_CONTROL) && is_layout_char_key(key, scancode, 'r')) {
+                    app->isearch_backward = 1;
+                    app_update_isearch(app);
+                    return;
+                }
+                return;
+        }
+    }
+
+    if (app->mode == APP_MODE_PROMPT) {
+        switch (key) {
+            case GLFW_KEY_ESCAPE:
+                app_cancel_prompt(app);
+                return;
+
+            case GLFW_KEY_ENTER:
+                app_submit_prompt(app);
+                return;
+
+            case GLFW_KEY_TAB:
+                app_cycle_prompt_completion(app, 1);
+                return;
+
+            case GLFW_KEY_DOWN:
+                app_cycle_prompt_completion(app, 1);
+                return;
+
+            case GLFW_KEY_UP:
+                app_cycle_prompt_completion(app, -1);
+                return;
+
+            case GLFW_KEY_BACKSPACE:
+                if (app->prompt_input_len > 0) {
+                    app_reset_prompt_completion(app);
+                    app->prompt_input_len--;
+                    app->prompt_input[app->prompt_input_len] = '\0';
+                    app->dirty = 1;
+                }
+                return;
+
+            default:
+                return;
+        }
+    }
+
+    if (app->mode == APP_MODE_PREFIX) {
+        if (key == GLFW_KEY_ESCAPE) {
+            app_cancel_prefix(app);
+            return;
+        }
+
+        char key_name[64];
+
+        if (key_event_to_string(key, scancode, mods, key_name, sizeof(key_name)) == 0) {
+            if (key_produces_text(key, scancode)) {
+                app->suppress_next_char = 1;
+            }
+
+            if (app_append_prefix_key(app, key_name) == 0) {
+                app_finish_prefix(app);
+            }
+            return;
+        }
+
+        app_cancel_prefix(app);
+        return;
+    }
+
+    char key_name[64];
+    if (key_event_to_string(key, scancode, mods, key_name, sizeof(key_name)) == 0) {
+        const char *command = ecex_lookup_key_for_buffer(app->ed, ecex_current_buffer(app->ed), key_name);
+        if (command) {
+            if (key_produces_text(key, scancode) &&
+                !(mods & GLFW_MOD_CONTROL) &&
+                !(mods & GLFW_MOD_SUPER)) {
+                app->suppress_next_char = 1;
+            }
+
+            try_execute_keybind(app, key_name);
+            return;
+        }
+    }
+
+    if (key == GLFW_KEY_ESCAPE) {
+        glfwSetWindowShouldClose(window, GLFW_TRUE);
+        glfwPostEmptyEvent();
+        return;
+    }
+}
+
+void app_init(app_t *app, ecex_t *ed) {
+    if (!app) return;
+
+    memset(app, 0, sizeof(*app));
+    app->ed = ed;
+    app->dirty = 1;
+    app->mode = APP_MODE_EDIT;
+    app_reset_completion(app);
+    app_reset_prompt_completion(app);
+}
+
+void app_set_window(app_t *app, GLFWwindow *window) {
+    if (!app) return;
+
+    app->window = window;
+    if (app->ed) {
+        ecex_set_clipboard_callbacks(app->ed,
+                                     window ? app_clipboard_get : NULL,
+                                     window ? app_clipboard_set : NULL,
+                                     app);
+    }
+    if (window) {
+        glfwSetWindowUserPointer(window, app);
+    }
+}
+
+void app_install_callbacks(app_t *app) {
+    if (!app || !app->window) return;
+
+    glfwSetCharCallback(app->window, char_callback);
+    glfwSetKeyCallback(app->window, key_callback);
+    glfwSetFramebufferSizeCallback(app->window, framebuffer_size_callback);
+    glfwSetWindowRefreshCallback(app->window, window_refresh_callback);
+    glfwSetMouseButtonCallback(app->window, mouse_button_callback);
+    glfwSetScrollCallback(app->window, scroll_callback);
+}
diff --git a/src/buffers.c b/src/buffers.c
new file mode 100644
index 0000000..e8c1d23
--- /dev/null
+++ b/src/buffers.c
@@ -0,0 +1,701 @@
+#include "buffers.h"
+
+#include "common.h"
+#include "util.h"
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define BUFFER_INITIAL_CAP 64
+
+static int buffer_is_word_char(char c) {
+    return (c >= 'a' && c <= 'z') ||
+           (c >= 'A' && c <= 'Z') ||
+           (c >= '0' && c <= '9') ||
+           c == '_';
+}
+
+static int buffer_require_editable(buffer_t *buffer) {
+    if (!buffer || buffer->read_only) return ECEX_ERR;
+    return ECEX_OK;
+}
+
+static void buffer_undo_entry_free(ecex_undo_entry_t *entry) {
+    if (!entry) return;
+    free(entry->data);
+    entry->data = NULL;
+    entry->len = 0;
+    entry->point = 0;
+    entry->mark = 0;
+    entry->mark_active = 0;
+}
+
+static void buffer_undo_stack_clear(ecex_undo_entry_t *stack, size_t count) {
+    if (!stack) return;
+    for (size_t i = 0; i < count; i++) buffer_undo_entry_free(&stack[i]);
+}
+
+static int buffer_push_snapshot_to(ecex_undo_entry_t **stack,
+                                   size_t *count,
+                                   size_t *cap,
+                                   buffer_t *buffer) {
+    if (!stack || !count || !cap || !buffer) return ECEX_ERR;
+    if (ECEX_GROW_ARRAY(*stack, *count, *cap, 64) != ECEX_OK) return ECEX_ERR;
+    ecex_undo_entry_t *entry = &(*stack)[(*count)++];
+    memset(entry, 0, sizeof(*entry));
+    entry->data = malloc(buffer->len + 1);
+    if (!entry->data) { (*count)--; return ECEX_ERR; }
+    memcpy(entry->data, buffer->data, buffer->len + 1);
+    entry->len = buffer->len;
+    entry->point = buffer->point;
+    entry->mark = buffer->mark;
+    entry->mark_active = buffer->mark_active;
+    return ECEX_OK;
+}
+
+static void buffer_clear_redo(buffer_t *buffer) {
+    if (!buffer) return;
+    buffer_undo_stack_clear(buffer->redo_stack, buffer->redo_count);
+    buffer->redo_count = 0;
+}
+
+static int buffer_record_undo(buffer_t *buffer) {
+    if (!buffer || buffer->undo_disabled) return ECEX_OK;
+    if (buffer_push_snapshot_to(&buffer->undo_stack,
+                                &buffer->undo_count,
+                                &buffer->undo_cap,
+                                buffer) != ECEX_OK) {
+        return ECEX_ERR;
+    }
+    buffer_clear_redo(buffer);
+    return ECEX_OK;
+}
+
+static int buffer_restore_snapshot(buffer_t *buffer, ecex_undo_entry_t *entry) {
+    if (!buffer || !entry || !entry->data) return ECEX_ERR;
+    char *copy = malloc(entry->len + 1);
+    if (!copy) return ECEX_ERR;
+    memcpy(copy, entry->data, entry->len + 1);
+    free(buffer->data);
+    buffer->data = copy;
+    buffer->len = entry->len;
+    buffer->cap = entry->len + 1;
+    buffer->point = ECEX_MIN(entry->point, buffer->len);
+    buffer->mark = ECEX_MIN(entry->mark, buffer->len);
+    buffer->mark_active = entry->mark_active;
+    buffer->modified = 1;
+    return ECEX_OK;
+}
+
+buffer_t *buffer_new(const char *name, const char *path, int read_only) {
+    assert(name && "buffer name cannot be NULL");
+
+    buffer_t *buffer = calloc(1, sizeof(*buffer));
+    if (!buffer) return NULL;
+
+    buffer->name = ecex_strdup(name);
+    buffer->path = ecex_strdup(path);
+    buffer->data = malloc(1);
+
+    if (!buffer->name || (path && !buffer->path) || !buffer->data) {
+        buffer_free(buffer);
+        return NULL;
+    }
+
+    buffer->data[0] = '\0';
+    buffer->len = 0;
+    buffer->cap = 1;
+    buffer->read_only = read_only;
+
+    return buffer;
+}
+
+void buffer_free(buffer_t *buffer) {
+    if (!buffer) return;
+
+    buffer_clear_interactive_actions(buffer);
+    buffer_undo_stack_clear(buffer->undo_stack, buffer->undo_count);
+    buffer_undo_stack_clear(buffer->redo_stack, buffer->redo_count);
+    free(buffer->undo_stack);
+    free(buffer->redo_stack);
+    free(buffer->interactive_actions);
+    free(buffer->name);
+    free(buffer->path);
+    free(buffer->data);
+    free(buffer);
+}
+
+int buffer_reserve(buffer_t *buffer, size_t needed) {
+    ECEX_RETURN_ERR_IF_NULL(buffer);
+    if (needed <= buffer->cap) return ECEX_OK;
+
+    size_t new_cap = buffer->cap ? buffer->cap : BUFFER_INITIAL_CAP;
+    while (new_cap < needed) {
+        new_cap *= 2;
+    }
+
+    char *new_data = realloc(buffer->data, new_cap);
+    if (!new_data) return ECEX_ERR;
+
+    buffer->data = new_data;
+    buffer->cap = new_cap;
+    return ECEX_OK;
+}
+
+int buffer_clear(buffer_t *buffer) {
+    if (buffer_require_editable(buffer) != ECEX_OK) return ECEX_ERR;
+    if (buffer_record_undo(buffer) != ECEX_OK) return ECEX_ERR;
+
+    if (buffer_reserve(buffer, 1) != ECEX_OK) return ECEX_ERR;
+
+    buffer->data[0] = '\0';
+    buffer->len = 0;
+    buffer->point = 0;
+    buffer->mark = 0;
+    buffer->mark_active = 0;
+    buffer->scroll_line = 0;
+    buffer->scroll_col = 0;
+    buffer_clear_interactive_actions(buffer);
+    buffer->modified = 1;
+    return ECEX_OK;
+}
+
+int buffer_set_text(buffer_t *buffer, const char *text) {
+    if (buffer_require_editable(buffer) != ECEX_OK || !text) return ECEX_ERR;
+    if (buffer_record_undo(buffer) != ECEX_OK) return ECEX_ERR;
+
+    size_t len = strlen(text);
+    if (buffer_reserve(buffer, len + 1) != ECEX_OK) return ECEX_ERR;
+
+    memcpy(buffer->data, text, len + 1);
+    buffer->len = len;
+    buffer->point = len;
+    buffer->mark = 0;
+    buffer->mark_active = 0;
+    buffer->scroll_line = 0;
+    buffer->scroll_col = 0;
+    buffer_clear_interactive_actions(buffer);
+    buffer->modified = 1;
+    return ECEX_OK;
+}
+
+int buffer_insert_at(buffer_t *buffer, size_t pos, const char *text) {
+    if (buffer_require_editable(buffer) != ECEX_OK || !text) return ECEX_ERR;
+    if (pos > buffer->len) return ECEX_ERR;
+
+    size_t text_len = strlen(text);
+    if (text_len == 0) return ECEX_OK;
+    if (buffer_record_undo(buffer) != ECEX_OK) return ECEX_ERR;
+    size_t needed = buffer->len + text_len + 1;
+
+    if (buffer_reserve(buffer, needed) != ECEX_OK) return ECEX_ERR;
+
+    memmove(buffer->data + pos + text_len,
+            buffer->data + pos,
+            buffer->len - pos + 1);
+    memcpy(buffer->data + pos, text, text_len);
+
+    buffer->len += text_len;
+    buffer->point = pos + text_len;
+    buffer->modified = 1;
+    return ECEX_OK;
+}
+
+int buffer_insert(buffer_t *buffer, const char *text) {
+    ECEX_RETURN_ERR_IF_NULL(buffer);
+    return buffer_insert_at(buffer, buffer->point, text);
+}
+
+int buffer_append(buffer_t *buffer, const char *text) {
+    ECEX_RETURN_ERR_IF_NULL(buffer);
+    return buffer_insert_at(buffer, buffer->len, text);
+}
+
+int buffer_prepend(buffer_t *buffer, const char *text) {
+    return buffer_insert_at(buffer, 0, text);
+}
+
+int buffer_insert_char_at(buffer_t *buffer, size_t pos, char c) {
+    if (buffer_require_editable(buffer) != ECEX_OK) return ECEX_ERR;
+    if (pos > buffer->len) return ECEX_ERR;
+    if (buffer_record_undo(buffer) != ECEX_OK) return ECEX_ERR;
+
+    if (buffer_reserve(buffer, buffer->len + 2) != ECEX_OK) return ECEX_ERR;
+
+    memmove(buffer->data + pos + 1,
+            buffer->data + pos,
+            buffer->len - pos + 1);
+
+    buffer->data[pos] = c;
+    buffer->len++;
+    buffer->point = pos + 1;
+    buffer->modified = 1;
+    return ECEX_OK;
+}
+
+int buffer_insert_char(buffer_t *buffer, char c) {
+    ECEX_RETURN_ERR_IF_NULL(buffer);
+    return buffer_insert_char_at(buffer, buffer->point, c);
+}
+
+int buffer_delete_range(buffer_t *buffer, size_t start, size_t end) {
+    if (buffer_require_editable(buffer) != ECEX_OK) return ECEX_ERR;
+    if (start > end || end > buffer->len) return ECEX_ERR;
+    if (start == end) return ECEX_OK;
+    if (buffer_record_undo(buffer) != ECEX_OK) return ECEX_ERR;
+
+    size_t deleted = end - start;
+
+    memmove(buffer->data + start,
+            buffer->data + end,
+            buffer->len - end + 1);
+
+    buffer->len -= deleted;
+
+    if (buffer->point > end) {
+        buffer->point -= deleted;
+    } else if (buffer->point > start) {
+        buffer->point = start;
+    }
+
+    if (buffer->mark > end) {
+        buffer->mark -= deleted;
+    } else if (buffer->mark > start) {
+        buffer->mark = start;
+    }
+
+    if (buffer->mark_active && buffer->mark == buffer->point) {
+        buffer->mark_active = 0;
+    }
+
+    buffer->modified = 1;
+    return ECEX_OK;
+}
+
+int buffer_delete_selection(buffer_t *buffer) {
+    if (!buffer_has_selection(buffer)) return ECEX_OK;
+
+    size_t start = 0;
+    size_t end = 0;
+    buffer_selection_range(buffer, &start, &end);
+
+    int result = buffer_delete_range(buffer, start, end);
+    if (result == ECEX_OK) buffer_clear_mark(buffer);
+    return result;
+}
+
+int buffer_replace_selection(buffer_t *buffer, const char *text) {
+    if (!buffer || !text) return ECEX_ERR;
+    if (!buffer_has_selection(buffer)) return buffer_insert(buffer, text);
+
+    size_t start = 0;
+    size_t end = 0;
+    buffer_selection_range(buffer, &start, &end);
+
+    if (buffer_delete_range(buffer, start, end) != ECEX_OK) return ECEX_ERR;
+    buffer->point = start;
+    buffer_clear_mark(buffer);
+    return buffer_insert(buffer, text);
+}
+
+int buffer_backspace(buffer_t *buffer) {
+    if (!buffer) return ECEX_ERR;
+    if (buffer_has_selection(buffer)) return buffer_delete_selection(buffer);
+    if (buffer->point == 0) return ECEX_OK;
+    return buffer_delete_range(buffer, buffer->point - 1, buffer->point);
+}
+
+int buffer_delete_forward(buffer_t *buffer) {
+    if (!buffer) return ECEX_ERR;
+    if (buffer_has_selection(buffer)) return buffer_delete_selection(buffer);
+    if (buffer->point >= buffer->len) return ECEX_OK;
+    return buffer_delete_range(buffer, buffer->point, buffer->point + 1);
+}
+
+int buffer_kill_line(buffer_t *buffer) {
+    if (!buffer) return ECEX_ERR;
+
+    size_t end = buffer_line_end_at(buffer, buffer->point);
+    if (end == buffer->point && end < buffer->len && buffer->data[end] == '\n') {
+        end++;
+    }
+
+    return buffer_delete_range(buffer, buffer->point, end);
+}
+
+void buffer_set_point(buffer_t *buffer, size_t point) {
+    if (!buffer) return;
+    buffer->point = ECEX_MIN(point, buffer->len);
+}
+
+void buffer_move_left(buffer_t *buffer) {
+    if (!buffer || buffer->point == 0) return;
+    buffer->point--;
+}
+
+void buffer_move_right(buffer_t *buffer) {
+    if (!buffer || buffer->point >= buffer->len) return;
+    buffer->point++;
+}
+
+void buffer_move_up(buffer_t *buffer) {
+    if (!buffer) return;
+
+    size_t current_start = buffer_line_start_at(buffer, buffer->point);
+    if (current_start == 0) {
+        buffer->point = 0;
+        return;
+    }
+
+    size_t wanted_col = buffer->point - current_start;
+    size_t prev_end = current_start - 1;
+    size_t prev_start = buffer_line_start_at(buffer, prev_end);
+    size_t prev_len = prev_end - prev_start;
+
+    buffer->point = prev_start + ECEX_MIN(wanted_col, prev_len);
+}
+
+void buffer_move_down(buffer_t *buffer) {
+    if (!buffer) return;
+
+    size_t current_start = buffer_line_start_at(buffer, buffer->point);
+    size_t current_end = buffer_line_end_at(buffer, buffer->point);
+    if (current_end >= buffer->len) {
+        buffer->point = buffer->len;
+        return;
+    }
+
+    size_t wanted_col = buffer->point - current_start;
+    size_t next_start = current_end + 1;
+    size_t next_end = buffer_line_end_at(buffer, next_start);
+    size_t next_len = next_end - next_start;
+
+    buffer->point = next_start + ECEX_MIN(wanted_col, next_len);
+}
+
+void buffer_move_word_left(buffer_t *buffer) {
+    if (!buffer) return;
+
+    size_t pos = buffer->point;
+    while (pos > 0 && !buffer_is_word_char(buffer->data[pos - 1])) pos--;
+    while (pos > 0 && buffer_is_word_char(buffer->data[pos - 1])) pos--;
+    buffer->point = pos;
+}
+
+void buffer_move_word_right(buffer_t *buffer) {
+    if (!buffer) return;
+
+    size_t pos = buffer->point;
+    while (pos < buffer->len && !buffer_is_word_char(buffer->data[pos])) pos++;
+    while (pos < buffer->len && buffer_is_word_char(buffer->data[pos])) pos++;
+    buffer->point = pos;
+}
+
+void buffer_move_beginning_of_line(buffer_t *buffer) {
+    if (!buffer) return;
+    buffer->point = buffer_line_start_at(buffer, buffer->point);
+}
+
+void buffer_move_end_of_line(buffer_t *buffer) {
+    if (!buffer) return;
+    buffer->point = buffer_line_end_at(buffer, buffer->point);
+}
+
+void buffer_move_beginning_of_buffer(buffer_t *buffer) {
+    if (!buffer) return;
+    buffer->point = 0;
+}
+
+void buffer_move_end_of_buffer(buffer_t *buffer) {
+    if (!buffer) return;
+    buffer->point = buffer->len;
+}
+
+void buffer_set_mark(buffer_t *buffer, size_t mark) {
+    if (!buffer) return;
+    buffer->mark = ECEX_MIN(mark, buffer->len);
+    buffer->mark_active = 1;
+}
+
+void buffer_clear_mark(buffer_t *buffer) {
+    if (!buffer) return;
+    buffer->mark_active = 0;
+}
+
+int buffer_has_selection(buffer_t *buffer) {
+    return buffer && buffer->mark_active && buffer->mark != buffer->point;
+}
+
+void buffer_selection_range(buffer_t *buffer, size_t *out_start, size_t *out_end) {
+    size_t start = 0;
+    size_t end = 0;
+
+    if (buffer && buffer_has_selection(buffer)) {
+        start = ECEX_MIN(buffer->point, buffer->mark);
+        end = ECEX_MAX(buffer->point, buffer->mark);
+    }
+
+    if (out_start) *out_start = start;
+    if (out_end) *out_end = end;
+}
+
+size_t buffer_line_start_at(buffer_t *buffer, size_t pos) {
+    if (!buffer) return 0;
+    pos = ECEX_MIN(pos, buffer->len);
+
+    while (pos > 0 && buffer->data[pos - 1] != '\n') {
+        pos--;
+    }
+
+    return pos;
+}
+
+size_t buffer_line_end_at(buffer_t *buffer, size_t pos) {
+    if (!buffer) return 0;
+    pos = ECEX_MIN(pos, buffer->len);
+
+    while (pos < buffer->len && buffer->data[pos] != '\n') {
+        pos++;
+    }
+
+    return pos;
+}
+
+size_t buffer_current_line_start(buffer_t *buffer) {
+    if (!buffer) return 0;
+    return buffer_line_start_at(buffer, buffer->point);
+}
+
+size_t buffer_current_line_end(buffer_t *buffer) {
+    if (!buffer) return 0;
+    return buffer_line_end_at(buffer, buffer->point);
+}
+
+size_t buffer_current_column(buffer_t *buffer) {
+    if (!buffer) return 0;
+    return buffer->point - buffer_line_start_at(buffer, buffer->point);
+}
+
+size_t buffer_current_line_number(buffer_t *buffer) {
+    if (!buffer) return 0;
+
+    size_t line = 1;
+    for (size_t i = 0; i < buffer->point && i < buffer->len; i++) {
+        if (buffer->data[i] == '\n') line++;
+    }
+
+    return line;
+}
+
+size_t buffer_line_count(buffer_t *buffer) {
+    if (!buffer || buffer->len == 0) return 1;
+
+    size_t lines = 1;
+    for (size_t i = 0; i < buffer->len; i++) {
+        if (buffer->data[i] == '\n') lines++;
+    }
+
+    return lines;
+}
+
+char *buffer_substring(buffer_t *buffer, size_t start, size_t end) {
+    if (!buffer || start > end || end > buffer->len) return NULL;
+
+    size_t len = end - start;
+    char *copy = malloc(len + 1);
+    if (!copy) return NULL;
+
+    memcpy(copy, buffer->data + start, len);
+    copy[len] = '\0';
+    return copy;
+}
+
+char *buffer_current_line_copy(buffer_t *buffer) {
+    if (!buffer) return NULL;
+    return buffer_substring(buffer,
+                            buffer_current_line_start(buffer),
+                            buffer_current_line_end(buffer));
+}
+
+int buffer_load_file(buffer_t *buffer, const char *path) {
+    if (buffer_require_editable(buffer) != ECEX_OK || !path) return ECEX_ERR;
+
+    size_t size = 0;
+    char *new_data = ecex_read_entire_file(path, &size);
+    if (!new_data) return ECEX_ERR;
+
+    char *new_path = ecex_strdup(path);
+    if (!new_path) {
+        free(new_data);
+        return ECEX_ERR;
+    }
+
+    free(buffer->data);
+    free(buffer->path);
+
+    buffer->data = new_data;
+    buffer->path = new_path;
+    buffer->len = size;
+    buffer->cap = size + 1;
+    buffer->point = 0;
+    buffer->mark = 0;
+    buffer->mark_active = 0;
+    buffer->scroll_line = 0;
+    buffer->scroll_col = 0;
+    buffer->modified = 0;
+    buffer_clear_undo(buffer);
+    return ECEX_OK;
+}
+
+int buffer_save(buffer_t *buffer) {
+    if (!buffer || buffer->read_only || !buffer->path) return ECEX_ERR;
+
+    FILE *file = fopen(buffer->path, "wb");
+    if (!file) return ECEX_ERR;
+
+    size_t written = fwrite(buffer->data, 1, buffer->len, file);
+    int close_result = fclose(file);
+
+    if (close_result != 0 || written != buffer->len) return ECEX_ERR;
+
+    buffer->modified = 0;
+    return ECEX_OK;
+}
+
+int buffer_save_as(buffer_t *buffer, const char *path) {
+    if (buffer_require_editable(buffer) != ECEX_OK || !path) return ECEX_ERR;
+
+    char *new_path = ecex_strdup(path);
+    if (!new_path) return ECEX_ERR;
+
+    free(buffer->path);
+    buffer->path = new_path;
+    return buffer_save(buffer);
+}
+
+
+
+int buffer_undo(buffer_t *buffer) {
+    if (buffer_require_editable(buffer) != ECEX_OK) return ECEX_ERR;
+    if (buffer->undo_count == 0) return ECEX_OK;
+    if (buffer_push_snapshot_to(&buffer->redo_stack, &buffer->redo_count, &buffer->redo_cap, buffer) != ECEX_OK) return ECEX_ERR;
+    ecex_undo_entry_t entry = buffer->undo_stack[--buffer->undo_count];
+    int result = buffer_restore_snapshot(buffer, &entry);
+    buffer_undo_entry_free(&entry);
+    return result;
+}
+
+int buffer_redo(buffer_t *buffer) {
+    if (buffer_require_editable(buffer) != ECEX_OK) return ECEX_ERR;
+    if (buffer->redo_count == 0) return ECEX_OK;
+    if (buffer_push_snapshot_to(&buffer->undo_stack, &buffer->undo_count, &buffer->undo_cap, buffer) != ECEX_OK) return ECEX_ERR;
+    ecex_undo_entry_t entry = buffer->redo_stack[--buffer->redo_count];
+    int result = buffer_restore_snapshot(buffer, &entry);
+    buffer_undo_entry_free(&entry);
+    return result;
+}
+
+void buffer_clear_undo(buffer_t *buffer) {
+    if (!buffer) return;
+    buffer_undo_stack_clear(buffer->undo_stack, buffer->undo_count);
+    buffer_undo_stack_clear(buffer->redo_stack, buffer->redo_count);
+    buffer->undo_count = 0;
+    buffer->redo_count = 0;
+}
+
+int buffer_search_forward(buffer_t *buffer, const char *query, size_t start, size_t *out_pos) {
+    if (!buffer || !query || !query[0]) return ECEX_ERR;
+    if (start > buffer->len) start = buffer->len;
+    char *hit = strstr(buffer->data + start, query);
+    if (!hit && start > 0) hit = strstr(buffer->data, query);
+    if (!hit) return ECEX_ERR;
+    if (out_pos) *out_pos = (size_t)(hit - buffer->data);
+    return ECEX_OK;
+}
+
+int buffer_search_backward(buffer_t *buffer, const char *query, size_t start, size_t *out_pos) {
+    if (!buffer || !query || !query[0]) return ECEX_ERR;
+    size_t qlen = strlen(query);
+    if (qlen > buffer->len) return ECEX_ERR;
+    if (start > buffer->len) start = buffer->len;
+    size_t best = (size_t)-1;
+    for (size_t i = 0; i + qlen <= start; i++) {
+        if (memcmp(buffer->data + i, query, qlen) == 0) best = i;
+    }
+    if (best == (size_t)-1) {
+        for (size_t i = start; i + qlen <= buffer->len; i++) {
+            if (memcmp(buffer->data + i, query, qlen) == 0) best = i;
+        }
+    }
+    if (best == (size_t)-1) return ECEX_ERR;
+    if (out_pos) *out_pos = best;
+    return ECEX_OK;
+}
+
+void buffer_set_interactive(buffer_t *buffer, int interactive) {
+    if (!buffer) return;
+    buffer->interactive = interactive ? 1 : 0;
+}
+
+int buffer_is_interactive(buffer_t *buffer) {
+    return buffer && buffer->interactive;
+}
+
+int buffer_clear_interactive_actions(buffer_t *buffer) {
+    if (!buffer) return ECEX_ERR;
+
+    for (size_t i = 0; i < buffer->interactive_action_count; i++) {
+        free(buffer->interactive_actions[i].payload);
+        buffer->interactive_actions[i].payload = NULL;
+        buffer->interactive_actions[i].fn = NULL;
+        buffer->interactive_actions[i].userdata = NULL;
+        buffer->interactive_actions[i].line = 0;
+    }
+
+    buffer->interactive_action_count = 0;
+    return ECEX_OK;
+}
+
+int buffer_add_interactive_action(buffer_t *buffer,
+                                  size_t line,
+                                  ecex_interactive_line_fn fn,
+                                  const char *payload,
+                                  void *userdata) {
+    if (!buffer || !fn) return ECEX_ERR;
+
+    if (ECEX_GROW_ARRAY(buffer->interactive_actions,
+                        buffer->interactive_action_count,
+                        buffer->interactive_action_cap,
+                        16) != ECEX_OK) {
+        return ECEX_ERR;
+    }
+
+    char *payload_copy = ecex_strdup(payload);
+    if (payload && !payload_copy) return ECEX_ERR;
+
+    ecex_interactive_line_action_t *action =
+        &buffer->interactive_actions[buffer->interactive_action_count++];
+
+    action->line = line;
+    action->fn = fn;
+    action->payload = payload_copy;
+    action->userdata = userdata;
+
+    buffer->interactive = 1;
+    return ECEX_OK;
+}
+
+ecex_interactive_line_action_t *buffer_interactive_action_at_line(buffer_t *buffer,
+                                                                  size_t line) {
+    if (!buffer || !buffer->interactive) return NULL;
+
+    for (size_t i = 0; i < buffer->interactive_action_count; i++) {
+        if (buffer->interactive_actions[i].line == line) {
+            return &buffer->interactive_actions[i];
+        }
+    }
+
+    return NULL;
+}
diff --git a/src/config.c b/src/config.c
new file mode 100644
index 0000000..b416d7a
--- /dev/null
+++ b/src/config.c
@@ -0,0 +1,293 @@
+#include "config.h"
+
+#include "buffers.h"
+#include "ccdjit.h"
+#include "common.h"
+#include "ecex.h"
+#include "eval.h"
+#include "util.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+typedef int (*ecex_config_init_fn)(ecex_t *ed);
+
+typedef struct host_symbol {
+    const char *name;
+    void *addr;
+} host_symbol_t;
+
+void ecex_print_ccdjit_error(ccdjit_context *ctx) {
+    const ccdjit_diagnostic *diag = ccdjit_context_last_error(ctx);
+
+    if (!diag) {
+        fprintf(stderr, "ccdjit: unknown error\n");
+        return;
+    }
+
+    fprintf(stderr,
+            "ccdjit error [%s] %s:%d:%d: %s\n",
+            diag->phase ? diag->phase : "?",
+            diag->filename ? diag->filename : "<input>",
+            diag->line,
+            diag->column,
+            diag->message ? diag->message : "(no message)");
+
+    if (diag->source_line) fprintf(stderr, "%s\n", diag->source_line);
+    if (diag->caret_line) fprintf(stderr, "%s\n", diag->caret_line);
+}
+
+#define HOST_SYMBOL(fn) { #fn, (void *)(fn) }
+
+static const host_symbol_t host_symbols[] = {
+    HOST_SYMBOL(ecex_current_buffer),
+    HOST_SYMBOL(ecex_create_buffer),
+    HOST_SYMBOL(ecex_find_buffer),
+    HOST_SYMBOL(ecex_switch_buffer),
+    HOST_SYMBOL(ecex_next_buffer),
+    HOST_SYMBOL(ecex_previous_buffer),
+    HOST_SYMBOL(ecex_current_window),
+    HOST_SYMBOL(ecex_window_count),
+    HOST_SYMBOL(ecex_split_window_vertically),
+    HOST_SYMBOL(ecex_split_window_horizontally),
+    HOST_SYMBOL(ecex_other_window),
+    HOST_SYMBOL(ecex_previous_window),
+    HOST_SYMBOL(ecex_delete_window),
+    HOST_SYMBOL(ecex_delete_other_windows),
+    HOST_SYMBOL(ecex_kill_buffer),
+
+    HOST_SYMBOL(ecex_register_command),
+    HOST_SYMBOL(ecex_execute_command),
+    HOST_SYMBOL(ecex_bind_key),
+    HOST_SYMBOL(ecex_lookup_key),
+    HOST_SYMBOL(ecex_define_major_mode),
+    HOST_SYMBOL(ecex_major_mode_by_name),
+    HOST_SYMBOL(ecex_major_mode_name),
+    HOST_SYMBOL(ecex_buffer_set_major_mode),
+    HOST_SYMBOL(ecex_buffer_set_major_mode_by_name),
+    HOST_SYMBOL(ecex_buffer_major_mode_name),
+    HOST_SYMBOL(ecex_bind_mode_key),
+    HOST_SYMBOL(ecex_lookup_key_for_buffer),
+    HOST_SYMBOL(ecex_key_sequence_has_prefix_for_buffer),
+    HOST_SYMBOL(ecex_auto_set_major_mode),
+    HOST_SYMBOL(ecex_list_commands),
+    HOST_SYMBOL(ecex_list_buffers),
+    HOST_SYMBOL(ecex_create_interactive_buffer),
+    HOST_SYMBOL(ecex_interactive_append_line),
+    HOST_SYMBOL(ecex_interactive_activate_current_line),
+    HOST_SYMBOL(ecex_find_file),
+    HOST_SYMBOL(ecex_save_current_buffer),
+    HOST_SYMBOL(ecex_write_current_buffer),
+    HOST_SYMBOL(ecex_request_prompt),
+    HOST_SYMBOL(ecex_clear_prompt_request),
+    HOST_SYMBOL(ecex_complete_command),
+    HOST_SYMBOL(ecex_eval_source),
+    HOST_SYMBOL(ecex_eval_current_buffer),
+    HOST_SYMBOL(ecex_eval_current_line),
+    HOST_SYMBOL(ecex_eval_current_region),
+    HOST_SYMBOL(ecex_eval_file),
+    HOST_SYMBOL(ecex_eval_rerun_last),
+
+    HOST_SYMBOL(ecex_set_font),
+    HOST_SYMBOL(ecex_get_font_size),
+    HOST_SYMBOL(ecex_set_font_size),
+    HOST_SYMBOL(ecex_adjust_font_size),
+    HOST_SYMBOL(ecex_set_bg_color),
+    HOST_SYMBOL(ecex_set_fg_color),
+    HOST_SYMBOL(ecex_set_status_bg_color),
+    HOST_SYMBOL(ecex_set_status_fg_color),
+    HOST_SYMBOL(ecex_set_status_border_color),
+    HOST_SYMBOL(ecex_set_cursor_color),
+    HOST_SYMBOL(ecex_set_region_bg_color),
+    HOST_SYMBOL(ecex_set_minibuffer_bg_color),
+    HOST_SYMBOL(ecex_set_minibuffer_fg_color),
+    HOST_SYMBOL(ecex_set_completion_fg_color),
+    HOST_SYMBOL(ecex_set_completion_enabled),
+    HOST_SYMBOL(ecex_set_interactive_highlight_bg_color),
+    HOST_SYMBOL(ecex_set_interactive_highlight_fg_color),
+
+    HOST_SYMBOL(buffer_clear),
+    HOST_SYMBOL(buffer_set_text),
+    HOST_SYMBOL(buffer_insert),
+    HOST_SYMBOL(buffer_insert_at),
+    HOST_SYMBOL(buffer_append),
+    HOST_SYMBOL(buffer_prepend),
+    HOST_SYMBOL(buffer_insert_char),
+    HOST_SYMBOL(buffer_insert_char_at),
+    HOST_SYMBOL(buffer_delete_range),
+    HOST_SYMBOL(buffer_delete_selection),
+    HOST_SYMBOL(buffer_replace_selection),
+    HOST_SYMBOL(buffer_backspace),
+    HOST_SYMBOL(buffer_delete_forward),
+    HOST_SYMBOL(buffer_kill_line),
+
+    HOST_SYMBOL(buffer_set_point),
+    HOST_SYMBOL(buffer_move_left),
+    HOST_SYMBOL(buffer_move_right),
+    HOST_SYMBOL(buffer_move_up),
+    HOST_SYMBOL(buffer_move_down),
+    HOST_SYMBOL(buffer_move_word_left),
+    HOST_SYMBOL(buffer_move_word_right),
+    HOST_SYMBOL(buffer_move_beginning_of_line),
+    HOST_SYMBOL(buffer_move_end_of_line),
+    HOST_SYMBOL(buffer_move_beginning_of_buffer),
+    HOST_SYMBOL(buffer_move_end_of_buffer),
+
+    HOST_SYMBOL(buffer_set_mark),
+    HOST_SYMBOL(buffer_clear_mark),
+    HOST_SYMBOL(buffer_has_selection),
+    HOST_SYMBOL(buffer_selection_range),
+
+    HOST_SYMBOL(buffer_line_start_at),
+    HOST_SYMBOL(buffer_line_end_at),
+    HOST_SYMBOL(buffer_current_line_start),
+    HOST_SYMBOL(buffer_current_line_end),
+    HOST_SYMBOL(buffer_current_column),
+    HOST_SYMBOL(buffer_current_line_number),
+    HOST_SYMBOL(buffer_line_count),
+    HOST_SYMBOL(buffer_substring),
+    HOST_SYMBOL(buffer_current_line_copy),
+
+    HOST_SYMBOL(buffer_load_file),
+    HOST_SYMBOL(buffer_save),
+    HOST_SYMBOL(buffer_save_as),
+    HOST_SYMBOL(buffer_set_interactive),
+    HOST_SYMBOL(buffer_is_interactive),
+    HOST_SYMBOL(buffer_clear_interactive_actions),
+    HOST_SYMBOL(buffer_add_interactive_action),
+    HOST_SYMBOL(buffer_interactive_action_at_line),
+};
+
+#undef HOST_SYMBOL
+
+int ecex_register_host_symbols(ccdjit_context *ctx) {
+    for (size_t i = 0; i < ECEX_ARRAY_LEN(host_symbols); i++) {
+        if (ccdjit_context_register_symbol(ctx,
+                                           host_symbols[i].name,
+                                           host_symbols[i].addr) != 0) {
+            fprintf(stderr, "ecex: failed to register symbol: %s\n", host_symbols[i].name);
+            ecex_print_ccdjit_error(ctx);
+            return ECEX_ERR;
+        }
+    }
+
+    return ECEX_OK;
+}
+
+static int add_include_path(ccdjit_context *ctx, const char *path) {
+    if (ccdjit_context_add_include_path(ctx, path) == 0) return ECEX_OK;
+
+    fprintf(stderr, "ecex: failed to add include path: %s\n", path);
+    ecex_print_ccdjit_error(ctx);
+    return ECEX_ERR;
+}
+
+int ecex_add_ccdjit_include_paths(ccdjit_context *ctx) {
+    if (add_include_path(ctx, "include") != ECEX_OK) return ECEX_ERR;
+    if (add_include_path(ctx, "../include") != ECEX_OK) return ECEX_ERR;
+
+    const char *env_include = getenv("ECEX_INCLUDE");
+    if (env_include && env_include[0]) {
+        if (add_include_path(ctx, env_include) != ECEX_OK) return ECEX_ERR;
+    }
+
+    return ECEX_OK;
+}
+
+static char *make_config_source_with_forced_main(const char *path) {
+    size_t source_size = 0;
+    char *source = ecex_read_entire_file(path, &source_size);
+    if (!source) return NULL;
+
+    const char *forced_main =
+        "\n"
+        "\n"
+        "int main(int argc, char **argv) {\n"
+        "    (void)argc;\n"
+        "    (void)argv;\n"
+        "    return ecex_config_init((ecex_t *)0);\n"
+        "}\n";
+
+    size_t forced_main_len = strlen(forced_main);
+    char *combined = malloc(source_size + forced_main_len + 1);
+    if (!combined) {
+        free(source);
+        return NULL;
+    }
+
+    memcpy(combined, source, source_size);
+    memcpy(combined + source_size, forced_main, forced_main_len + 1);
+
+    free(source);
+    return combined;
+}
+
+int ecex_load_c_config(ecex_t *ed, const char *path) {
+    if (!ed || !path) return ECEX_ERR;
+
+    ccdjit_context *ctx = ccdjit_context_new(NULL);
+    if (!ctx) {
+        fprintf(stderr, "ecex: failed to create ccdjit context\n");
+        return ECEX_ERR;
+    }
+
+    if (ecex_add_ccdjit_include_paths(ctx) != ECEX_OK || ecex_register_host_symbols(ctx) != ECEX_OK) {
+        ccdjit_context_free(ctx);
+        return ECEX_ERR;
+    }
+
+    char *source = make_config_source_with_forced_main(path);
+    if (!source) {
+        fprintf(stderr, "ecex: failed to read or prepare config: %s\n", path);
+        ccdjit_context_free(ctx);
+        return ECEX_ERR;
+    }
+
+    ccdjit_module *module = NULL;
+    if (ccdjit_compile_string(ctx, source, path, &module) != 0) {
+        fprintf(stderr, "ecex: failed to compile config: %s\n", path);
+        ecex_print_ccdjit_error(ctx);
+        free(source);
+        ccdjit_context_free(ctx);
+        return ECEX_ERR;
+    }
+
+    free(source);
+
+    ecex_config_init_fn init =
+        (ecex_config_init_fn)ccdjit_module_symbol(module, "ecex_config_init");
+
+    if (!init) {
+        fprintf(stderr, "ecex: config missing function: ecex_config_init\n");
+        ecex_print_ccdjit_error(ctx);
+        ccdjit_module_free(module);
+        ccdjit_context_free(ctx);
+        return ECEX_ERR;
+    }
+
+    int result = init(ed);
+    if (result != 0) {
+        fprintf(stderr, "ecex: config init failed with code: %d\n", result);
+        ccdjit_module_free(module);
+        ccdjit_context_free(ctx);
+        return ECEX_ERR;
+    }
+
+    if (ecex_keep_jit_module(ed, module) != ECEX_OK) {
+        fprintf(stderr, "ecex: failed to retain config module\n");
+        ccdjit_module_free(module);
+        ccdjit_context_free(ctx);
+        return ECEX_ERR;
+    }
+
+    if (ecex_set_config_path(ed, path) != ECEX_OK) {
+        fprintf(stderr, "ecex: failed to remember config path: %s\n", path);
+        ccdjit_context_free(ctx);
+        return ECEX_ERR;
+    }
+
+    ccdjit_context_free(ctx);
+    fprintf(stderr, "ecex: loaded config: %s\n", path);
+    return ECEX_OK;
+}
diff --git a/src/ecex.c b/src/ecex.c
new file mode 100644
index 0000000..2f4c962
--- /dev/null
+++ b/src/ecex.c
@@ -0,0 +1,1630 @@
+#include "ecex.h"
+
+#include "ccdjit.h"
+#include "common.h"
+#include "config.h"
+#include "util.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+extern FILE *popen(const char *command, const char *type);
+extern int pclose(FILE *stream);
+
+#define ECEX_INITIAL_BUFFER_CAP 8
+#define ECEX_INITIAL_COMMAND_CAP 32
+#define ECEX_INITIAL_KEYBIND_CAP 32
+#define ECEX_INITIAL_WINDOW_CAP 4
+#define ECEX_INITIAL_MODE_CAP 8
+#define ECEX_INITIAL_MODE_KEYBIND_CAP 16
+
+ecex_window_t *ecex_current_window(ecex_t *ed);
+
+static ecex_color_t ecex_color(float r, float g, float b) {
+    ecex_color_t c = {r, g, b};
+    return c;
+}
+
+static void ecex_theme_set_defaults(ecex_t *ed) {
+    if (!ed) return;
+
+    ed->theme.font_path = NULL;
+    ed->theme.font_size = 22.0f;
+
+    ed->theme.bg = ecex_color(0.08f, 0.09f, 0.11f);
+    ed->theme.fg = ecex_color(0.88f, 0.88f, 0.86f);
+
+    ed->theme.status_bg = ecex_color(0.15f, 0.15f, 0.18f);
+    ed->theme.status_fg = ecex_color(0.86f, 0.86f, 0.84f);
+    ed->theme.status_border = ecex_color(0.28f, 0.28f, 0.32f);
+
+    ed->theme.cursor = ecex_color(1.0f, 1.0f, 1.0f);
+    ed->theme.region_bg = ecex_color(0.22f, 0.34f, 0.48f);
+
+    ed->theme.minibuffer_bg = ecex_color(0.10f, 0.11f, 0.14f);
+    ed->theme.minibuffer_fg = ecex_color(0.95f, 0.95f, 0.90f);
+
+    ed->theme.completion_fg = ecex_color(0.45f, 0.45f, 0.45f);
+    ed->theme.completion_enabled = 1;
+
+    ed->theme.interactive_highlight_bg = ecex_color(0.18f, 0.20f, 0.24f);
+    ed->theme.interactive_highlight_fg = ecex_color(1.0f, 1.0f, 1.0f);
+    ed->theme.current_line_bg = ecex_color(0.12f, 0.13f, 0.16f);
+    ed->theme.search_bg = ecex_color(0.55f, 0.42f, 0.12f);
+    ed->theme.line_numbers_enabled = 1;
+    ed->theme.current_line_enabled = 1;
+}
+
+#define ECEX_COMMAND(name, fn) \
+    do { \
+        if (ecex_register_command(ed, (name), (fn)) != ECEX_OK) return ECEX_ERR; \
+    } while (0)
+
+#define ECEX_BIND(key, command) \
+    do { \
+        if (ecex_bind_key(ed, (key), (command)) != ECEX_OK) return ECEX_ERR; \
+    } while (0)
+
+#define CURRENT_BUFFER_OR_ERR(ed) \
+    buffer_t *buf = ecex_current_buffer(ed); \
+    if (!buf) return ECEX_ERR
+
+static int cmd_quit(ecex_t *ed) {
+    if (!ed) return ECEX_ERR;
+    ed->should_quit = 1;
+    return ECEX_OK;
+}
+
+static int cmd_next_buffer(ecex_t *ed) { return ecex_next_buffer(ed); }
+static int cmd_previous_buffer(ecex_t *ed) { return ecex_previous_buffer(ed); }
+static int cmd_split_window_right(ecex_t *ed) { return ecex_split_window_vertically(ed); }
+static int cmd_split_window_below(ecex_t *ed) { return ecex_split_window_horizontally(ed); }
+static int cmd_other_window(ecex_t *ed) { return ecex_other_window(ed); }
+static int cmd_previous_window(ecex_t *ed) { return ecex_previous_window(ed); }
+static int cmd_delete_window(ecex_t *ed) { return ecex_delete_window(ed); }
+static int cmd_delete_other_windows(ecex_t *ed) { return ecex_delete_other_windows(ed); }
+static int cmd_balance_windows(ecex_t *ed) { return ecex_balance_windows(ed); }
+
+static int cmd_move_left(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_left(buf); return ECEX_OK; }
+static int cmd_move_right(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_right(buf); return ECEX_OK; }
+static int cmd_move_up(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_up(buf); return ECEX_OK; }
+static int cmd_move_down(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_down(buf); return ECEX_OK; }
+static int cmd_move_word_left(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_word_left(buf); return ECEX_OK; }
+static int cmd_move_word_right(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_word_right(buf); return ECEX_OK; }
+static int cmd_beginning_of_line(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_beginning_of_line(buf); return ECEX_OK; }
+static int cmd_end_of_line(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_end_of_line(buf); return ECEX_OK; }
+static int cmd_beginning_of_buffer(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_beginning_of_buffer(buf); return ECEX_OK; }
+static int cmd_end_of_buffer(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_move_end_of_buffer(buf); return ECEX_OK; }
+
+static int cmd_undo(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); return buffer_undo(buf); }
+static int cmd_redo(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); return buffer_redo(buf); }
+static int cmd_backspace(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); return buffer_backspace(buf); }
+static int cmd_delete_forward(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); return buffer_delete_forward(buf); }
+static int cmd_newline(ecex_t *ed) {
+    CURRENT_BUFFER_OR_ERR(ed);
+    if (buffer_is_interactive(buf)) {
+        return ecex_interactive_activate_current_line(ed);
+    }
+    return buffer_insert_char(buf, '\n');
+}
+static int cmd_kill_line(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); return buffer_kill_line(buf); }
+static int cmd_clear_buffer(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); return buffer_clear(buf); }
+static int cmd_set_mark(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_set_mark(buf, buf->point); return ECEX_OK; }
+static int cmd_clear_mark(ecex_t *ed) { CURRENT_BUFFER_OR_ERR(ed); buffer_clear_mark(buf); return ECEX_OK; }
+
+
+static int cmd_yank(ecex_t *ed) {
+    CURRENT_BUFFER_OR_ERR(ed);
+    const char *text = ecex_clipboard_get(ed);
+    if (!text || !text[0]) return ECEX_OK;
+    return buffer_replace_selection(buf, text);
+}
+
+static int cmd_copy_region(ecex_t *ed) {
+    CURRENT_BUFFER_OR_ERR(ed);
+    if (!buffer_has_selection(buf)) return ECEX_OK;
+
+    size_t start = 0;
+    size_t end = 0;
+    buffer_selection_range(buf, &start, &end);
+
+    char *text = buffer_substring(buf, start, end);
+    if (!text) return ECEX_ERR;
+
+    int result = ecex_clipboard_set(ed, text);
+    free(text);
+    return result;
+}
+
+static int cmd_kill_region(ecex_t *ed) {
+    CURRENT_BUFFER_OR_ERR(ed);
+    if (!buffer_has_selection(buf)) return ECEX_OK;
+
+    size_t start = 0;
+    size_t end = 0;
+    buffer_selection_range(buf, &start, &end);
+
+    char *text = buffer_substring(buf, start, end);
+    if (!text) return ECEX_ERR;
+
+    int result = ecex_clipboard_set(ed, text);
+    free(text);
+    if (result != ECEX_OK) return result;
+
+    return buffer_delete_selection(buf);
+}
+
+static int cmd_list_commands(ecex_t *ed) { return ecex_list_commands(ed); }
+static int cmd_list_buffers(ecex_t *ed) { return ecex_list_buffers(ed); }
+static int cmd_switch_buffer(ecex_t *ed) { ecex_request_prompt(ed, ECEX_PROMPT_SWITCH_BUFFER, "Switch buffer: "); return ECEX_OK; }
+static int cmd_kill_buffer_command(ecex_t *ed) { ecex_request_prompt(ed, ECEX_PROMPT_KILL_BUFFER, "Kill buffer: "); return ECEX_OK; }
+static int cmd_compile(ecex_t *ed) { ecex_request_prompt(ed, ECEX_PROMPT_COMPILE, "Compile: "); return ECEX_OK; }
+static int cmd_grep(ecex_t *ed) { ecex_request_prompt(ed, ECEX_PROMPT_GREP, "Grep: "); return ECEX_OK; }
+static int cmd_recompile(ecex_t *ed) { return ecex_rerun_compile(ed); }
+static int cmd_regrep(ecex_t *ed) { return ecex_rerun_grep(ed); }
+static int cmd_next_error(ecex_t *ed) { return ecex_next_interactive_action(ed); }
+static int cmd_previous_error(ecex_t *ed) { return ecex_previous_interactive_action(ed); }
+static int cmd_comment_region(ecex_t *ed) { return ecex_comment_region(ed); }
+static int cmd_uncomment_region(ecex_t *ed) { return ecex_uncomment_region(ed); }
+static int cmd_toggle_line_numbers(ecex_t *ed) { if (!ed) return ECEX_ERR; ed->theme.line_numbers_enabled = !ed->theme.line_numbers_enabled; return ECEX_OK; }
+static int cmd_toggle_current_line(ecex_t *ed) { if (!ed) return ECEX_ERR; ed->theme.current_line_enabled = !ed->theme.current_line_enabled; return ECEX_OK; }
+static int cmd_isearch_forward(ecex_t *ed) { ecex_request_prompt(ed, ECEX_PROMPT_ISEARCH_FORWARD, "I-search: "); return ECEX_OK; }
+static int cmd_isearch_backward(ecex_t *ed) { ecex_request_prompt(ed, ECEX_PROMPT_ISEARCH_BACKWARD, "I-search backward: "); return ECEX_OK; }
+
+static int cmd_find_file(ecex_t *ed) {
+    ecex_request_prompt(ed, ECEX_PROMPT_FIND_FILE, "Find file: ");
+    return ECEX_OK;
+}
+
+static int cmd_write_file(ecex_t *ed) {
+    ecex_request_prompt(ed, ECEX_PROMPT_WRITE_FILE, "Write file: ");
+    return ECEX_OK;
+}
+
+static int cmd_save_buffer(ecex_t *ed) {
+    if (!ed) return ECEX_ERR;
+
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf) return ECEX_ERR;
+
+    if (!buf->path) {
+        ecex_request_prompt(ed, ECEX_PROMPT_WRITE_FILE, "Write file: ");
+        return ECEX_OK;
+    }
+
+    return ecex_save_current_buffer(ed);
+}
+
+static int cmd_eval_buffer(ecex_t *ed) {
+    return ecex_eval_current_buffer(ed);
+}
+
+static int cmd_eval_line(ecex_t *ed) {
+    return ecex_eval_current_line(ed);
+}
+
+static int cmd_eval_region(ecex_t *ed) {
+    return ecex_eval_current_region(ed);
+}
+
+static int cmd_eval_file(ecex_t *ed) {
+    ecex_request_prompt(ed, ECEX_PROMPT_EVAL_FILE, "Eval file: ");
+    return ECEX_OK;
+}
+
+static int cmd_eval_rerun_last(ecex_t *ed) {
+    return ecex_eval_rerun_last(ed);
+}
+
+static int cmd_quit_window(ecex_t *ed) {
+    if (!ed) return ECEX_ERR;
+    if (ecex_window_count(ed) > 1) return ecex_delete_window(ed);
+    return ecex_previous_buffer(ed);
+}
+
+static int cmd_reload_config(ecex_t *ed) {
+    return ecex_reload_config(ed);
+}
+
+static int ecex_register_builtins(ecex_t *ed) {
+    ECEX_COMMAND("quit", cmd_quit);
+    ECEX_COMMAND("find-file", cmd_find_file);
+    ECEX_COMMAND("save-buffer", cmd_save_buffer);
+    ECEX_COMMAND("write-file", cmd_write_file);
+    ECEX_COMMAND("eval-buffer", cmd_eval_buffer);
+    ECEX_COMMAND("eval-line", cmd_eval_line);
+    ECEX_COMMAND("eval-region", cmd_eval_region);
+    ECEX_COMMAND("eval-selection", cmd_eval_region);
+    ECEX_COMMAND("eval-file", cmd_eval_file);
+    ECEX_COMMAND("eval-rerun-last", cmd_eval_rerun_last);
+    ECEX_COMMAND("revert-eval-buffer", cmd_eval_rerun_last);
+    ECEX_COMMAND("quit-window", cmd_quit_window);
+    ECEX_COMMAND("reload-config", cmd_reload_config);
+    ECEX_COMMAND("list-commands", cmd_list_commands);
+    ECEX_COMMAND("list-buffers", cmd_list_buffers);
+    ECEX_COMMAND("switch-buffer", cmd_switch_buffer);
+    ECEX_COMMAND("kill-buffer", cmd_kill_buffer_command);
+    ECEX_COMMAND("compile", cmd_compile);
+    ECEX_COMMAND("recompile", cmd_recompile);
+    ECEX_COMMAND("grep", cmd_grep);
+    ECEX_COMMAND("regrep", cmd_regrep);
+    ECEX_COMMAND("next-error", cmd_next_error);
+    ECEX_COMMAND("previous-error", cmd_previous_error);
+    ECEX_COMMAND("comment-region", cmd_comment_region);
+    ECEX_COMMAND("uncomment-region", cmd_uncomment_region);
+    ECEX_COMMAND("toggle-line-numbers", cmd_toggle_line_numbers);
+    ECEX_COMMAND("toggle-current-line", cmd_toggle_current_line);
+    ECEX_COMMAND("isearch-forward", cmd_isearch_forward);
+    ECEX_COMMAND("isearch-backward", cmd_isearch_backward);
+
+    ECEX_COMMAND("next-buffer", cmd_next_buffer);
+    ECEX_COMMAND("previous-buffer", cmd_previous_buffer);
+    ECEX_COMMAND("split-window-right", cmd_split_window_right);
+    ECEX_COMMAND("split-window-vertically", cmd_split_window_right);
+    ECEX_COMMAND("split-window-below", cmd_split_window_below);
+    ECEX_COMMAND("split-window-horizontally", cmd_split_window_below);
+    ECEX_COMMAND("other-window", cmd_other_window);
+    ECEX_COMMAND("previous-window", cmd_previous_window);
+    ECEX_COMMAND("delete-window", cmd_delete_window);
+    ECEX_COMMAND("delete-other-windows", cmd_delete_other_windows);
+    ECEX_COMMAND("balance-windows", cmd_balance_windows);
+
+    ECEX_COMMAND("move-left", cmd_move_left);
+    ECEX_COMMAND("move-right", cmd_move_right);
+    ECEX_COMMAND("move-up", cmd_move_up);
+    ECEX_COMMAND("move-down", cmd_move_down);
+    ECEX_COMMAND("move-word-left", cmd_move_word_left);
+    ECEX_COMMAND("move-word-right", cmd_move_word_right);
+    ECEX_COMMAND("beginning-of-line", cmd_beginning_of_line);
+    ECEX_COMMAND("end-of-line", cmd_end_of_line);
+    ECEX_COMMAND("beginning-of-buffer", cmd_beginning_of_buffer);
+    ECEX_COMMAND("end-of-buffer", cmd_end_of_buffer);
+
+    ECEX_COMMAND("undo", cmd_undo);
+    ECEX_COMMAND("redo", cmd_redo);
+    ECEX_COMMAND("backspace", cmd_backspace);
+    ECEX_COMMAND("delete-forward", cmd_delete_forward);
+    ECEX_COMMAND("newline", cmd_newline);
+    ECEX_COMMAND("kill-line", cmd_kill_line);
+    ECEX_COMMAND("clear-buffer", cmd_clear_buffer);
+    ECEX_COMMAND("set-mark", cmd_set_mark);
+    ECEX_COMMAND("clear-mark", cmd_clear_mark);
+    ECEX_COMMAND("yank", cmd_yank);
+    ECEX_COMMAND("paste", cmd_yank);
+    ECEX_COMMAND("copy-region", cmd_copy_region);
+    ECEX_COMMAND("copy-region-as-kill", cmd_copy_region);
+    ECEX_COMMAND("kill-region", cmd_kill_region);
+
+    ECEX_BIND("LEFT", "move-left");
+    ECEX_BIND("RIGHT", "move-right");
+    ECEX_BIND("UP", "move-up");
+    ECEX_BIND("DOWN", "move-down");
+
+    ECEX_BIND("C-b", "move-left");
+    ECEX_BIND("C-f", "move-right");
+    ECEX_BIND("C-p", "move-up");
+    ECEX_BIND("C-n", "move-down");
+    ECEX_BIND("C-a", "beginning-of-line");
+    ECEX_BIND("C-e", "end-of-line");
+    ECEX_BIND("C-k", "kill-line");
+    ECEX_BIND("C-SPC", "set-mark");
+    ECEX_BIND("C-y", "yank");
+    ECEX_BIND("C-v", "paste");
+    ECEX_BIND("M-w", "copy-region-as-kill");
+    ECEX_BIND("C-w", "kill-region");
+    ECEX_BIND("C-s", "isearch-forward");
+    ECEX_BIND("C-r", "isearch-backward");
+    ECEX_BIND("C-/", "undo");
+    ECEX_BIND("C-z", "undo");
+    ECEX_BIND("C-S-z", "redo");
+
+    ECEX_BIND("C-x C-f", "find-file");
+    ECEX_BIND("C-x C-s", "save-buffer");
+    ECEX_BIND("C-x C-w", "write-file");
+    ECEX_BIND("C-x C-b", "list-buffers");
+    ECEX_BIND("C-x b", "switch-buffer");
+    ECEX_BIND("C-x k", "kill-buffer");
+    ECEX_BIND("C-x 2", "split-window-below");
+    ECEX_BIND("C-x 3", "split-window-right");
+    ECEX_BIND("C-x o", "other-window");
+    ECEX_BIND("C-x O", "previous-window");
+    ECEX_BIND("C-x 0", "delete-window");
+    ECEX_BIND("C-x 1", "delete-other-windows");
+    ECEX_BIND("C-x +", "balance-windows");
+    ECEX_BIND("C-x e b", "eval-buffer");
+    ECEX_BIND("C-x e l", "eval-line");
+    ECEX_BIND("C-x C-e", "eval-line");
+    ECEX_BIND("C-x e r", "eval-region");
+    ECEX_BIND("C-x e f", "eval-file");
+    ECEX_BIND("C-x C-r", "reload-config");
+    ECEX_BIND("F5", "reload-config");
+    ECEX_BIND("M-g n", "next-error");
+    ECEX_BIND("M-g p", "previous-error");
+    ECEX_BIND("M-;", "comment-region");
+
+    ECEX_BIND("BACKSPACE", "backspace");
+    ECEX_BIND("DELETE", "delete-forward");
+    ECEX_BIND("ENTER", "newline");
+
+    ecex_define_major_mode(ed, "fundamental-mode");
+    ecex_define_major_mode(ed, "c-mode");
+    ecex_define_major_mode(ed, "eval-output-mode");
+    ecex_define_major_mode(ed, "special-mode");
+    ecex_bind_mode_key(ed, "eval-output-mode", "g", "eval-rerun-last");
+    ecex_bind_mode_key(ed, "eval-output-mode", "q", "quit-window");
+    ecex_bind_mode_key(ed, "eval-output-mode", "r", "eval-rerun-last");
+    ecex_bind_mode_key(ed, "special-mode", "q", "quit-window");
+    ecex_bind_mode_key(ed, "special-mode", "g", "recompile");
+    ecex_bind_mode_key(ed, "special-mode", "n", "next-error");
+    ecex_bind_mode_key(ed, "special-mode", "p", "previous-error");
+
+    return ECEX_OK;
+}
+
+#undef ECEX_COMMAND
+#undef ECEX_BIND
+#undef CURRENT_BUFFER_OR_ERR
+
+ecex_t *ecex_new(void) {
+    ecex_t *ed = calloc(1, sizeof(*ed));
+    if (!ed) return NULL;
+
+    ecex_theme_set_defaults(ed);
+
+    buffer_t *scratch = buffer_new("*scratch*", NULL, 0);
+    if (!scratch || ecex_add_buffer(ed, scratch) != ECEX_OK) {
+        buffer_free(scratch);
+        ecex_free(ed);
+        return NULL;
+    }
+
+    ed->current_buffer_index = 0;
+    ed->current_buffer = scratch;
+    ed->next_major_mode_id = 1;
+
+    ed->window_cap = ECEX_INITIAL_WINDOW_CAP;
+    ed->windows = calloc(ed->window_cap, sizeof(*ed->windows));
+    if (!ed->windows) {
+        ecex_free(ed);
+        return NULL;
+    }
+    ed->window_count = 1;
+    ed->current_window_index = 0;
+    ed->windows[0].buffer = scratch;
+    ed->windows[0].x = 0.0f;
+    ed->windows[0].y = 0.0f;
+    ed->windows[0].w = 1.0f;
+    ed->windows[0].h = 1.0f;
+
+    if (ecex_register_builtins(ed) != ECEX_OK) {
+        ecex_free(ed);
+        return NULL;
+    }
+
+    ecex_buffer_set_major_mode_by_name(ed, scratch, "fundamental-mode");
+
+    return ed;
+}
+
+void ecex_free(ecex_t *ed) {
+    if (!ed) return;
+
+    for (size_t i = 0; i < ed->jit_module_count; i++) {
+        ccdjit_module_free((ccdjit_module *)ed->jit_modules[i]);
+    }
+
+    for (size_t i = 0; i < ed->buffer_count; i++) {
+        buffer_free(ed->buffers[i]);
+    }
+
+    for (size_t i = 0; i < ed->command_count; i++) {
+        free(ed->commands[i].name);
+    }
+
+    for (size_t i = 0; i < ed->keybind_count; i++) {
+        free(ed->keybinds[i].key);
+        free(ed->keybinds[i].command);
+    }
+
+    for (size_t i = 0; i < ed->mode_keybind_count; i++) {
+        free(ed->mode_keybinds[i].key);
+        free(ed->mode_keybinds[i].command);
+    }
+
+    for (size_t i = 0; i < ed->major_mode_count; i++) {
+        free(ed->major_modes[i].name);
+    }
+
+    free(ed->jit_modules);
+    free(ed->windows);
+    free(ed->buffers);
+    free(ed->commands);
+    free(ed->keybinds);
+    free(ed->mode_keybinds);
+    free(ed->major_modes);
+    free(ed->last_eval_source);
+    free(ed->last_eval_filename);
+    free(ed->last_compile_command);
+    free(ed->last_grep_command);
+    free(ed->config_path);
+    free(ed->theme.font_path);
+    free(ed);
+}
+
+int ecex_reserve_buffers(ecex_t *ed, size_t needed) {
+    ECEX_RETURN_ERR_IF_NULL(ed);
+    if (needed <= ed->buffer_cap) return ECEX_OK;
+
+    while (ed->buffer_cap < needed) {
+        if (ECEX_GROW_ARRAY(ed->buffers,
+                            ed->buffer_count,
+                            ed->buffer_cap,
+                            ECEX_INITIAL_BUFFER_CAP) != ECEX_OK) {
+            return ECEX_ERR;
+        }
+    }
+
+    return ECEX_OK;
+}
+
+int ecex_add_buffer(ecex_t *ed, buffer_t *buffer) {
+    if (!ed || !buffer) return ECEX_ERR;
+
+    if (ecex_reserve_buffers(ed, ed->buffer_count + 1) != ECEX_OK) return ECEX_ERR;
+
+    ed->buffers[ed->buffer_count++] = buffer;
+
+    if (!ed->current_buffer) {
+        ed->current_buffer_index = 0;
+        ed->current_buffer = buffer;
+    }
+
+    return ECEX_OK;
+}
+
+buffer_t *ecex_create_buffer(ecex_t *ed,
+                             const char *name,
+                             const char *path,
+                             int read_only) {
+    if (!ed || !name) return NULL;
+
+    buffer_t *buffer = buffer_new(name, path, read_only);
+    if (!buffer) return NULL;
+
+    if (ecex_add_buffer(ed, buffer) != ECEX_OK) {
+        buffer_free(buffer);
+        return NULL;
+    }
+
+    return buffer;
+}
+
+buffer_t *ecex_find_buffer(ecex_t *ed, const char *name) {
+    if (!ed || !name) return NULL;
+
+    for (size_t i = 0; i < ed->buffer_count; i++) {
+        if (strcmp(ed->buffers[i]->name, name) == 0) {
+            return ed->buffers[i];
+        }
+    }
+
+    return NULL;
+}
+
+
+static int ecex_set_current_buffer_index(ecex_t *ed, size_t index) {
+    if (!ed || index >= ed->buffer_count) return ECEX_ERR;
+    ed->current_buffer_index = index;
+    ed->current_buffer = ed->buffers[index];
+    ecex_window_t *win = ecex_current_window(ed);
+    if (win) win->buffer = ed->current_buffer;
+    return ECEX_OK;
+}
+
+int ecex_sync_current_buffer(ecex_t *ed) {
+    if (!ed) return ECEX_ERR;
+    ecex_window_t *win = ecex_current_window(ed);
+    if (!win || !win->buffer) return ECEX_ERR;
+
+    ed->current_buffer = win->buffer;
+    for (size_t i = 0; i < ed->buffer_count; i++) {
+        if (ed->buffers[i] == win->buffer) {
+            ed->current_buffer_index = i;
+            return ECEX_OK;
+        }
+    }
+    return ECEX_ERR;
+}
+
+int ecex_switch_buffer(ecex_t *ed, const char *name) {
+    if (!ed || !name) return ECEX_ERR;
+
+    for (size_t i = 0; i < ed->buffer_count; i++) {
+        if (strcmp(ed->buffers[i]->name, name) == 0) {
+            return ecex_set_current_buffer_index(ed, i);
+        }
+    }
+
+    return ECEX_ERR;
+}
+
+buffer_t *ecex_current_buffer(ecex_t *ed) {
+    if (!ed) return NULL;
+    ecex_window_t *win = ecex_current_window(ed);
+    if (win && win->buffer) return win->buffer;
+    return ed->current_buffer;
+}
+
+ecex_window_t *ecex_current_window(ecex_t *ed) {
+    if (!ed || ed->window_count == 0 || ed->current_window_index >= ed->window_count) return NULL;
+    return &ed->windows[ed->current_window_index];
+}
+
+size_t ecex_window_count(ecex_t *ed) {
+    return ed ? ed->window_count : 0;
+}
+
+static int ecex_reserve_windows(ecex_t *ed, size_t needed) {
+    if (!ed) return ECEX_ERR;
+    if (needed <= ed->window_cap) return ECEX_OK;
+    while (ed->window_cap < needed) {
+        if (ECEX_GROW_ARRAY(ed->windows,
+                            ed->window_count,
+                            ed->window_cap,
+                            ECEX_INITIAL_WINDOW_CAP) != ECEX_OK) {
+            return ECEX_ERR;
+        }
+    }
+    return ECEX_OK;
+}
+
+static int ecex_add_window(ecex_t *ed, ecex_window_t win) {
+    if (!ed || !win.buffer) return ECEX_ERR;
+    if (ecex_reserve_windows(ed, ed->window_count + 1) != ECEX_OK) return ECEX_ERR;
+    ed->windows[ed->window_count++] = win;
+    return ECEX_OK;
+}
+
+int ecex_split_window_vertically(ecex_t *ed) {
+    ecex_window_t *active = ecex_current_window(ed);
+    if (!active || !active->buffer || active->w < 0.08f) return ECEX_ERR;
+
+    ecex_window_t new_win = *active;
+    float half = active->w * 0.5f;
+    active->w = half;
+    new_win.x = active->x + half;
+    new_win.w = half;
+
+    if (ecex_add_window(ed, new_win) != ECEX_OK) return ECEX_ERR;
+    ed->current_window_index = ed->window_count - 1;
+    return ecex_sync_current_buffer(ed);
+}
+
+int ecex_split_window_horizontally(ecex_t *ed) {
+    ecex_window_t *active = ecex_current_window(ed);
+    if (!active || !active->buffer || active->h < 0.08f) return ECEX_ERR;
+
+    ecex_window_t new_win = *active;
+    float half = active->h * 0.5f;
+    active->h = half;
+    new_win.y = active->y + half;
+    new_win.h = half;
+
+    if (ecex_add_window(ed, new_win) != ECEX_OK) return ECEX_ERR;
+    ed->current_window_index = ed->window_count - 1;
+    return ecex_sync_current_buffer(ed);
+}
+
+int ecex_other_window(ecex_t *ed) {
+    if (!ed || ed->window_count == 0) return ECEX_ERR;
+    ed->current_window_index = (ed->current_window_index + 1) % ed->window_count;
+    return ecex_sync_current_buffer(ed);
+}
+
+int ecex_previous_window(ecex_t *ed) {
+    if (!ed || ed->window_count == 0) return ECEX_ERR;
+    if (ed->current_window_index == 0) ed->current_window_index = ed->window_count - 1;
+    else ed->current_window_index--;
+    return ecex_sync_current_buffer(ed);
+}
+
+int ecex_delete_window(ecex_t *ed) {
+    if (!ed || ed->window_count <= 1 || ed->current_window_index >= ed->window_count) return ECEX_ERR;
+
+    size_t index = ed->current_window_index;
+    for (size_t i = index; i + 1 < ed->window_count; i++) {
+        ed->windows[i] = ed->windows[i + 1];
+    }
+    ed->window_count--;
+    if (ed->current_window_index >= ed->window_count) ed->current_window_index = ed->window_count - 1;
+    return ecex_sync_current_buffer(ed);
+}
+
+int ecex_delete_other_windows(ecex_t *ed) {
+    ecex_window_t *active = ecex_current_window(ed);
+    if (!ed || !active) return ECEX_ERR;
+    ecex_window_t keep = *active;
+    keep.x = 0.0f; keep.y = 0.0f; keep.w = 1.0f; keep.h = 1.0f;
+    ed->windows[0] = keep;
+    ed->window_count = 1;
+    ed->current_window_index = 0;
+    return ecex_sync_current_buffer(ed);
+}
+
+int ecex_balance_windows(ecex_t *ed) {
+    if (!ed || ed->window_count == 0) return ECEX_ERR;
+    size_t n = ed->window_count;
+    size_t cols = 1;
+    while (cols * cols < n) cols++;
+    size_t rows = (n + cols - 1) / cols;
+    for (size_t i = 0; i < n; i++) {
+        size_t row = i / cols;
+        size_t col = i % cols;
+        ed->windows[i].x = (float)col / (float)cols;
+        ed->windows[i].y = (float)row / (float)rows;
+        ed->windows[i].w = 1.0f / (float)cols;
+        ed->windows[i].h = 1.0f / (float)rows;
+    }
+    return ecex_sync_current_buffer(ed);
+}
+
+int ecex_next_buffer(ecex_t *ed) {
+    if (!ed || ed->buffer_count == 0) return ECEX_ERR;
+    ecex_sync_current_buffer(ed);
+    return ecex_set_current_buffer_index(ed, (ed->current_buffer_index + 1) % ed->buffer_count);
+}
+
+int ecex_previous_buffer(ecex_t *ed) {
+    if (!ed || ed->buffer_count == 0) return ECEX_ERR;
+    ecex_sync_current_buffer(ed);
+
+    if (ed->current_buffer_index == 0) {
+        ed->current_buffer_index = ed->buffer_count - 1;
+    } else {
+        ed->current_buffer_index--;
+    }
+
+    return ecex_set_current_buffer_index(ed, ed->current_buffer_index);
+}
+
+int ecex_kill_buffer(ecex_t *ed, const char *name) {
+    if (!ed || !name || ed->buffer_count == 0) return ECEX_ERR;
+
+    size_t index = ed->buffer_count;
+    for (size_t i = 0; i < ed->buffer_count; i++) {
+        if (strcmp(ed->buffers[i]->name, name) == 0) {
+            index = i;
+            break;
+        }
+    }
+
+    if (index == ed->buffer_count) return ECEX_ERR;
+
+    buffer_t *victim = ed->buffers[index];
+
+    for (size_t i = index; i + 1 < ed->buffer_count; i++) {
+        ed->buffers[i] = ed->buffers[i + 1];
+    }
+
+    ed->buffer_count--;
+
+    buffer_t *fallback = ed->buffer_count > 0 ? ed->buffers[0] : NULL;
+    for (size_t i = 0; i < ed->window_count; i++) {
+        if (ed->windows[i].buffer == victim) {
+            ed->windows[i].buffer = fallback;
+        }
+    }
+
+    buffer_free(victim);
+
+    if (ed->buffer_count == 0) {
+        ed->current_buffer = NULL;
+        ed->current_buffer_index = 0;
+        ed->window_count = 0;
+        ed->current_window_index = 0;
+        return ECEX_OK;
+    }
+
+    if (ed->current_window_index >= ed->window_count) {
+        ed->current_window_index = ed->window_count ? ed->window_count - 1 : 0;
+    }
+
+    return ecex_sync_current_buffer(ed);
+}
+
+int ecex_keep_jit_module(ecex_t *ed, void *module) {
+    if (!ed || !module) return ECEX_ERR;
+
+    if (ECEX_GROW_ARRAY(ed->jit_modules,
+                        ed->jit_module_count,
+                        ed->jit_module_cap,
+                        8) != ECEX_OK) {
+        return ECEX_ERR;
+    }
+
+    ed->jit_modules[ed->jit_module_count++] = module;
+    return ECEX_OK;
+}
+
+int ecex_set_config_path(ecex_t *ed, const char *path) {
+    if (!ed) return ECEX_ERR;
+
+    char *copy = NULL;
+    if (path && path[0]) {
+        copy = ecex_strdup(path);
+        if (!copy) return ECEX_ERR;
+    }
+
+    free(ed->config_path);
+    ed->config_path = copy;
+    return ECEX_OK;
+}
+
+const char *ecex_config_path(ecex_t *ed) {
+    if (!ed) return NULL;
+    return ed->config_path;
+}
+
+static void ecex_clear_commands(ecex_t *ed) {
+    if (!ed) return;
+
+    for (size_t i = 0; i < ed->command_count; i++) {
+        free(ed->commands[i].name);
+    }
+    ed->command_count = 0;
+}
+
+static void ecex_clear_keybinds(ecex_t *ed) {
+    if (!ed) return;
+
+    for (size_t i = 0; i < ed->keybind_count; i++) {
+        free(ed->keybinds[i].key);
+        free(ed->keybinds[i].command);
+    }
+    ed->keybind_count = 0;
+}
+
+static void ecex_clear_mode_keybinds(ecex_t *ed) {
+    if (!ed) return;
+
+    for (size_t i = 0; i < ed->mode_keybind_count; i++) {
+        free(ed->mode_keybinds[i].key);
+        free(ed->mode_keybinds[i].command);
+    }
+    ed->mode_keybind_count = 0;
+}
+
+int ecex_reload_config(ecex_t *ed) {
+    if (!ed || !ed->config_path || !ed->config_path[0]) {
+        fprintf(stderr, "ecex: no config file to reload; start with --config path/to/ecexrc.c\n");
+        return ECEX_ERR;
+    }
+
+    char *path = ecex_strdup(ed->config_path);
+    if (!path) return ECEX_ERR;
+
+    ecex_clear_commands(ed);
+    ecex_clear_keybinds(ed);
+    ecex_clear_mode_keybinds(ed);
+
+    if (ecex_register_builtins(ed) != ECEX_OK) {
+        free(path);
+        return ECEX_ERR;
+    }
+
+    int result = ecex_load_c_config(ed, path);
+    free(path);
+    return result;
+}
+
+int ecex_register_command(ecex_t *ed, const char *name, ecex_command_fn fn) {
+    if (!ed || !name || !fn) return ECEX_ERR;
+
+    for (size_t i = 0; i < ed->command_count; i++) {
+        if (strcmp(ed->commands[i].name, name) == 0) {
+            ed->commands[i].fn = fn;
+            return ECEX_OK;
+        }
+    }
+
+    if (ECEX_GROW_ARRAY(ed->commands,
+                        ed->command_count,
+                        ed->command_cap,
+                        ECEX_INITIAL_COMMAND_CAP) != ECEX_OK) {
+        return ECEX_ERR;
+    }
+
+    char *copy = ecex_strdup(name);
+    if (!copy) return ECEX_ERR;
+
+    ed->commands[ed->command_count].name = copy;
+    ed->commands[ed->command_count].fn = fn;
+    ed->command_count++;
+    return ECEX_OK;
+}
+
+int ecex_execute_command(ecex_t *ed, const char *name) {
+    if (!ed || !name) return ECEX_ERR;
+
+    for (size_t i = 0; i < ed->command_count; i++) {
+        if (strcmp(ed->commands[i].name, name) == 0) {
+            return ed->commands[i].fn(ed);
+        }
+    }
+
+    return ECEX_ERR;
+}
+
+void ecex_set_clipboard_callbacks(ecex_t *ed,
+                                  ecex_clipboard_get_fn get_fn,
+                                  ecex_clipboard_set_fn set_fn,
+                                  void *userdata) {
+    if (!ed) return;
+    ed->clipboard_get = get_fn;
+    ed->clipboard_set = set_fn;
+    ed->clipboard_userdata = userdata;
+}
+
+const char *ecex_clipboard_get(ecex_t *ed) {
+    if (!ed || !ed->clipboard_get) return NULL;
+    return ed->clipboard_get(ed->clipboard_userdata);
+}
+
+int ecex_clipboard_set(ecex_t *ed, const char *text) {
+    if (!ed || !ed->clipboard_set || !text) return ECEX_ERR;
+    ed->clipboard_set(ed->clipboard_userdata, text);
+    return ECEX_OK;
+}
+
+int ecex_bind_key(ecex_t *ed, const char *key, const char *command) {
+    if (!ed || !key || !command) return ECEX_ERR;
+
+    for (size_t i = 0; i < ed->keybind_count; i++) {
+        if (strcmp(ed->keybinds[i].key, key) == 0) {
+            char *new_command = ecex_strdup(command);
+            if (!new_command) return ECEX_ERR;
+
+            free(ed->keybinds[i].command);
+            ed->keybinds[i].command = new_command;
+            return ECEX_OK;
+        }
+    }
+
+    if (ECEX_GROW_ARRAY(ed->keybinds,
+                        ed->keybind_count,
+                        ed->keybind_cap,
+                        ECEX_INITIAL_KEYBIND_CAP) != ECEX_OK) {
+        return ECEX_ERR;
+    }
+
+    char *key_copy = ecex_strdup(key);
+    char *command_copy = ecex_strdup(command);
+    if (!key_copy || !command_copy) {
+        free(key_copy);
+        free(command_copy);
+        return ECEX_ERR;
+    }
+
+    ed->keybinds[ed->keybind_count].key = key_copy;
+    ed->keybinds[ed->keybind_count].command = command_copy;
+    ed->keybind_count++;
+    return ECEX_OK;
+}
+
+const char *ecex_lookup_key(ecex_t *ed, const char *key) {
+    if (!ed || !key) return NULL;
+
+    for (size_t i = 0; i < ed->keybind_count; i++) {
+        if (strcmp(ed->keybinds[i].key, key) == 0) {
+            return ed->keybinds[i].command;
+        }
+    }
+
+    return NULL;
+}
+
+int ecex_define_major_mode(ecex_t *ed, const char *name) {
+    if (!ed || !name || !name[0]) return 0;
+
+    for (size_t i = 0; i < ed->major_mode_count; i++) {
+        if (strcmp(ed->major_modes[i].name, name) == 0) {
+            return ed->major_modes[i].id;
+        }
+    }
+
+    if (ECEX_GROW_ARRAY(ed->major_modes,
+                        ed->major_mode_count,
+                        ed->major_mode_cap,
+                        ECEX_INITIAL_MODE_CAP) != ECEX_OK) {
+        return 0;
+    }
+
+    char *copy = ecex_strdup(name);
+    if (!copy) return 0;
+
+    int id = ed->next_major_mode_id++;
+    ed->major_modes[ed->major_mode_count].id = id;
+    ed->major_modes[ed->major_mode_count].name = copy;
+    ed->major_mode_count++;
+    return id;
+}
+
+int ecex_major_mode_by_name(ecex_t *ed, const char *name) {
+    if (!ed || !name) return 0;
+    for (size_t i = 0; i < ed->major_mode_count; i++) {
+        if (strcmp(ed->major_modes[i].name, name) == 0) return ed->major_modes[i].id;
+    }
+    return 0;
+}
+
+const char *ecex_major_mode_name(ecex_t *ed, int mode) {
+    if (!ed || mode == 0) return "fundamental-mode";
+    for (size_t i = 0; i < ed->major_mode_count; i++) {
+        if (ed->major_modes[i].id == mode) return ed->major_modes[i].name;
+    }
+    return "unknown-mode";
+}
+
+int ecex_buffer_set_major_mode(buffer_t *buffer, int mode) {
+    if (!buffer) return ECEX_ERR;
+    buffer->major_mode = mode;
+    return ECEX_OK;
+}
+
+int ecex_buffer_set_major_mode_by_name(ecex_t *ed, buffer_t *buffer, const char *name) {
+    if (!ed || !buffer || !name) return ECEX_ERR;
+    int mode = ecex_define_major_mode(ed, name);
+    if (!mode) return ECEX_ERR;
+    return ecex_buffer_set_major_mode(buffer, mode);
+}
+
+const char *ecex_buffer_major_mode_name(ecex_t *ed, buffer_t *buffer) {
+    if (!buffer) return "fundamental-mode";
+    return ecex_major_mode_name(ed, buffer->major_mode);
+}
+
+int ecex_bind_mode_key(ecex_t *ed, const char *mode_name, const char *key, const char *command) {
+    if (!ed || !mode_name || !key || !command) return ECEX_ERR;
+
+    int mode = ecex_define_major_mode(ed, mode_name);
+    if (!mode) return ECEX_ERR;
+
+    for (size_t i = 0; i < ed->mode_keybind_count; i++) {
+        if (ed->mode_keybinds[i].mode == mode && strcmp(ed->mode_keybinds[i].key, key) == 0) {
+            char *new_command = ecex_strdup(command);
+            if (!new_command) return ECEX_ERR;
+            free(ed->mode_keybinds[i].command);
+            ed->mode_keybinds[i].command = new_command;
+            return ECEX_OK;
+        }
+    }
+
+    if (ECEX_GROW_ARRAY(ed->mode_keybinds,
+                        ed->mode_keybind_count,
+                        ed->mode_keybind_cap,
+                        ECEX_INITIAL_MODE_KEYBIND_CAP) != ECEX_OK) {
+        return ECEX_ERR;
+    }
+
+    char *key_copy = ecex_strdup(key);
+    char *command_copy = ecex_strdup(command);
+    if (!key_copy || !command_copy) {
+        free(key_copy);
+        free(command_copy);
+        return ECEX_ERR;
+    }
+
+    ed->mode_keybinds[ed->mode_keybind_count].mode = mode;
+    ed->mode_keybinds[ed->mode_keybind_count].key = key_copy;
+    ed->mode_keybinds[ed->mode_keybind_count].command = command_copy;
+    ed->mode_keybind_count++;
+    return ECEX_OK;
+}
+
+const char *ecex_lookup_key_for_buffer(ecex_t *ed, buffer_t *buffer, const char *key) {
+    if (!ed || !key) return NULL;
+
+    int mode = buffer ? buffer->major_mode : 0;
+    if (mode) {
+        for (size_t i = 0; i < ed->mode_keybind_count; i++) {
+            if (ed->mode_keybinds[i].mode == mode && strcmp(ed->mode_keybinds[i].key, key) == 0) {
+                return ed->mode_keybinds[i].command;
+            }
+        }
+    }
+
+    return ecex_lookup_key(ed, key);
+}
+
+int ecex_key_sequence_has_prefix_for_buffer(ecex_t *ed, buffer_t *buffer, const char *prefix) {
+    if (!ed || !prefix) return 0;
+    size_t prefix_len = strlen(prefix);
+    int mode = buffer ? buffer->major_mode : 0;
+
+    if (mode) {
+        for (size_t i = 0; i < ed->mode_keybind_count; i++) {
+            const char *key = ed->mode_keybinds[i].key;
+            if (ed->mode_keybinds[i].mode == mode &&
+                strncmp(key, prefix, prefix_len) == 0 && key[prefix_len] == ' ') {
+                return 1;
+            }
+        }
+    }
+
+    for (size_t i = 0; i < ed->keybind_count; i++) {
+        const char *key = ed->keybinds[i].key;
+        if (strncmp(key, prefix, prefix_len) == 0 && key[prefix_len] == ' ') return 1;
+    }
+
+    return 0;
+}
+
+int ecex_auto_set_major_mode(ecex_t *ed, buffer_t *buffer) {
+    if (!ed || !buffer) return ECEX_ERR;
+
+    const char *name = "fundamental-mode";
+    const char *path = buffer->path ? buffer->path : buffer->name;
+    const char *dot = path ? strrchr(path, '.') : NULL;
+
+    if (dot && (strcmp(dot, ".c") == 0 || strcmp(dot, ".h") == 0 ||
+                strcmp(dot, ".cc") == 0 || strcmp(dot, ".cpp") == 0 ||
+                strcmp(dot, ".hpp") == 0)) {
+        name = "c-mode";
+    }
+
+    if (buffer_is_interactive(buffer) && buffer->name && buffer->name[0] == '*') {
+        name = "special-mode";
+    }
+
+    return ecex_buffer_set_major_mode_by_name(ed, buffer, name);
+}
+
+int ecex_list_commands(ecex_t *ed) {
+    if (!ed) return ECEX_ERR;
+
+    buffer_t *buf = ecex_find_buffer(ed, "*commands*");
+    if (!buf) {
+        buf = ecex_create_buffer(ed, "*commands*", NULL, 0);
+        if (!buf) return ECEX_ERR;
+    }
+
+    if (buffer_clear(buf) != ECEX_OK) return ECEX_ERR;
+    buffer_append(buf, "Commands:\n\n");
+
+    for (size_t i = 0; i < ed->command_count; i++) {
+        const char *command_name = ed->commands[i].name;
+        int first_key = 1;
+
+        buffer_append(buf, "  ");
+        buffer_append(buf, command_name);
+
+        for (size_t j = 0; j < ed->keybind_count; j++) {
+            if (strcmp(ed->keybinds[j].command, command_name) == 0) {
+                buffer_append(buf, first_key ? "    [" : ", ");
+                buffer_append(buf, ed->keybinds[j].key);
+                first_key = 0;
+            }
+        }
+
+        for (size_t j = 0; j < ed->mode_keybind_count; j++) {
+            if (strcmp(ed->mode_keybinds[j].command, command_name) == 0) {
+                buffer_append(buf, first_key ? "    [" : ", ");
+                buffer_append(buf, ecex_major_mode_name(ed, ed->mode_keybinds[j].mode));
+                buffer_append(buf, ":");
+                buffer_append(buf, ed->mode_keybinds[j].key);
+                first_key = 0;
+            }
+        }
+
+        if (!first_key) buffer_append(buf, "]");
+        buffer_append(buf, "\n");
+    }
+
+    buf->point = 0;
+    buf->modified = 0;
+    return ecex_switch_buffer(ed, "*commands*");
+}
+
+
+
+static int ecex_interactive_switch_buffer_action(ecex_t *ed,
+                                                 buffer_t *buffer,
+                                                 size_t line,
+                                                 const char *payload,
+                                                 void *userdata) {
+    (void)buffer;
+    (void)line;
+    (void)userdata;
+
+    if (!ed || !payload) return ECEX_ERR;
+    return ecex_switch_buffer(ed, payload);
+}
+
+int ecex_list_buffers(ecex_t *ed) {
+    if (!ed) return ECEX_ERR;
+
+    buffer_t *buf = ecex_find_buffer(ed, "*buffers*");
+    if (!buf) {
+        buf = ecex_create_interactive_buffer(ed, "*buffers*");
+        if (!buf) return ECEX_ERR;
+    }
+
+    buffer_set_interactive(buf, 1);
+    if (buffer_clear(buf) != ECEX_OK) return ECEX_ERR;
+    buffer_set_interactive(buf, 1);
+
+    buffer_append(buf, "Buffers:\n");
+    buffer_append(buf, "Press ENTER on a buffer to switch to it.\n\n");
+
+    for (size_t i = 0; i < ed->buffer_count; i++) {
+        buffer_t *b = ed->buffers[i];
+        char line[1024];
+
+        snprintf(line,
+                 sizeof(line),
+                 "%s %s %-24s %-18s size:%zu%s%s",
+                 b == ed->current_buffer ? "*" : " ",
+                 b->modified ? "+" : " ",
+                 b->name ? b->name : "(unnamed)",
+                 ecex_buffer_major_mode_name(ed, b),
+                 b->len,
+                 b->path ? "    " : "",
+                 b->path ? b->path : "");
+
+        if (ecex_interactive_append_line(ed,
+                                         buf,
+                                         line,
+                                         ecex_interactive_switch_buffer_action,
+                                         b->name,
+                                         NULL) != ECEX_OK) {
+            return ECEX_ERR;
+        }
+    }
+
+    buf->point = 0;
+    buf->modified = 0;
+    return ecex_switch_buffer(ed, "*buffers*");
+}
+
+buffer_t *ecex_create_interactive_buffer(ecex_t *ed, const char *name) {
+    if (!ed || !name) return NULL;
+
+    buffer_t *buffer = ecex_find_buffer(ed, name);
+    if (!buffer) {
+        buffer = ecex_create_buffer(ed, name, NULL, 0);
+        if (!buffer) return NULL;
+    }
+
+    buffer_set_interactive(buffer, 1);
+    if (buffer->major_mode == 0) ecex_buffer_set_major_mode_by_name(ed, buffer, "special-mode");
+    return buffer;
+}
+
+int ecex_interactive_append_line(ecex_t *ed,
+                                 buffer_t *buffer,
+                                 const char *text,
+                                 ecex_interactive_line_fn fn,
+                                 const char *payload,
+                                 void *userdata) {
+    (void)ed;
+
+    if (!buffer || !text) return ECEX_ERR;
+
+    size_t line = buffer_line_count(buffer);
+    if (line > 0) line--;
+
+    if (fn) {
+        if (buffer_add_interactive_action(buffer, line, fn, payload, userdata) != ECEX_OK) {
+            return ECEX_ERR;
+        }
+    }
+
+    if (buffer_append(buffer, text) != ECEX_OK) return ECEX_ERR;
+    if (buffer_append(buffer, "\n") != ECEX_OK) return ECEX_ERR;
+
+    buffer_set_interactive(buffer, 1);
+    return ECEX_OK;
+}
+
+int ecex_interactive_activate_current_line(ecex_t *ed) {
+    if (!ed) return ECEX_ERR;
+
+    buffer_t *buffer = ecex_current_buffer(ed);
+    if (!buffer || !buffer_is_interactive(buffer)) return ECEX_ERR;
+
+    size_t line = buffer_current_line_number(buffer);
+    if (line > 0) line--;
+
+    ecex_interactive_line_action_t *action =
+        buffer_interactive_action_at_line(buffer, line);
+
+    if (!action || !action->fn) return ECEX_ERR;
+    return action->fn(ed, buffer, line, action->payload, action->userdata);
+}
+
+static const char *ecex_basename(const char *path) {
+    if (!path || !path[0]) return "untitled";
+
+    const char *last_slash = strrchr(path, '/');
+    if (last_slash && last_slash[1]) return last_slash + 1;
+    if (last_slash && last_slash == path) return "/";
+    return path;
+}
+
+static int ecex_buffer_path_equal(buffer_t *buffer, const char *path) {
+    return buffer && buffer->path && path && strcmp(buffer->path, path) == 0;
+}
+
+int ecex_find_file(ecex_t *ed, const char *path) {
+    if (!ed || !path || !path[0]) return ECEX_ERR;
+
+    for (size_t i = 0; i < ed->buffer_count; i++) {
+        if (ecex_buffer_path_equal(ed->buffers[i], path)) {
+            return ecex_set_current_buffer_index(ed, i);
+        }
+    }
+
+    const char *name = ecex_basename(path);
+    buffer_t *buf = ecex_create_buffer(ed, name, NULL, 0);
+    if (!buf) return ECEX_ERR;
+
+    if (ecex_file_exists(path)) {
+        if (buffer_load_file(buf, path) != ECEX_OK) {
+            ecex_kill_buffer(ed, buf->name);
+            return ECEX_ERR;
+        }
+    } else {
+        char *new_path = ecex_strdup(path);
+        if (!new_path) {
+            ecex_kill_buffer(ed, buf->name);
+            return ECEX_ERR;
+        }
+
+        free(buf->path);
+        buf->path = new_path;
+        buf->modified = 0;
+    }
+
+    ecex_auto_set_major_mode(ed, buf);
+    return ecex_set_current_buffer_index(ed, ed->buffer_count ? ed->buffer_count - 1 : 0);
+}
+
+int ecex_save_current_buffer(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf) return ECEX_ERR;
+    return buffer_save(buf);
+}
+
+int ecex_write_current_buffer(ecex_t *ed, const char *path) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf || !path || !path[0]) return ECEX_ERR;
+    int result = buffer_save_as(buf, path);
+    if (result == ECEX_OK) ecex_auto_set_major_mode(ed, buf);
+    return result;
+}
+
+void ecex_request_prompt(ecex_t *ed,
+                         ecex_prompt_request_t request,
+                         const char *message) {
+    if (!ed) return;
+
+    ed->prompt_request = request;
+    snprintf(ed->prompt_message,
+             sizeof(ed->prompt_message),
+             "%s",
+             message ? message : "");
+}
+
+void ecex_clear_prompt_request(ecex_t *ed) {
+    if (!ed) return;
+    ed->prompt_request = ECEX_PROMPT_NONE;
+    ed->prompt_message[0] = '\0';
+}
+
+static int ecex_fuzzy_score(const char *candidate, const char *query) {
+    if (!candidate || !query) return -1;
+    if (query[0] == '\0') return 0;
+
+    int score = 0;
+    int consecutive = 0;
+    int last_match = -1;
+    size_t ci = 0;
+    size_t qi = 0;
+
+    while (candidate[ci] && query[qi]) {
+        char c = candidate[ci];
+        char q = query[qi];
+
+        if (c >= 'A' && c <= 'Z') c = (char)(c - 'A' + 'a');
+        if (q >= 'A' && q <= 'Z') q = (char)(q - 'A' + 'a');
+
+        if (c == q) {
+            score += 10;
+
+            if ((int)ci == last_match + 1) {
+                consecutive++;
+                score += 5 * consecutive;
+            } else {
+                consecutive = 0;
+            }
+
+            if (ci == 0) score += 20;
+            if (ci > 0 && (candidate[ci - 1] == '-' ||
+                           candidate[ci - 1] == '_' ||
+                           candidate[ci - 1] == ' ')) {
+                score += 15;
+            }
+
+            last_match = (int)ci;
+            qi++;
+        }
+
+        ci++;
+    }
+
+    if (query[qi] != '\0') return -1;
+
+    score -= (int)strlen(candidate);
+    if (strncmp(candidate, query, strlen(query)) == 0) score += 100;
+    return score;
+}
+
+const char *ecex_complete_command(ecex_t *ed, const char *query) {
+    if (!ed || !query || !ed->theme.completion_enabled) return NULL;
+
+    const char *best = NULL;
+    int best_score = -1;
+
+    for (size_t i = 0; i < ed->command_count; i++) {
+        const char *name = ed->commands[i].name;
+        int score = ecex_fuzzy_score(name, query);
+
+        if (score > best_score) {
+            best_score = score;
+            best = name;
+        }
+    }
+
+    return best;
+}
+
+
+static int ecex_set_owned_string(char **slot, const char *value) {
+    if (!slot) return ECEX_ERR;
+    char *copy = NULL;
+    if (value && value[0]) {
+        copy = ecex_strdup(value);
+        if (!copy) return ECEX_ERR;
+    }
+    free(*slot);
+    *slot = copy;
+    return ECEX_OK;
+}
+
+static int ecex_parse_file_line(const char *text, char *path, size_t path_size, size_t *out_line) {
+    if (!text || !path || path_size == 0 || !out_line) return ECEX_ERR;
+    const char *colon = strchr(text, ':');
+    if (!colon || colon == text) return ECEX_ERR;
+    char *end = NULL;
+    long line = strtol(colon + 1, &end, 10);
+    if (line <= 0 || end == colon + 1) return ECEX_ERR;
+    size_t len = (size_t)(colon - text);
+    if (len >= path_size) len = path_size - 1;
+    memcpy(path, text, len);
+    path[len] = '\0';
+    *out_line = (size_t)line;
+    return ECEX_OK;
+}
+
+static int ecex_goto_file_line_action(ecex_t *ed, buffer_t *buffer, size_t line, const char *payload, void *userdata) {
+    (void)buffer;
+    (void)line;
+    (void)userdata;
+    if (!ed || !payload) return ECEX_ERR;
+    char path[1024];
+    size_t target_line = 1;
+    if (ecex_parse_file_line(payload, path, sizeof(path), &target_line) != ECEX_OK) return ECEX_ERR;
+    if (ecex_find_file(ed, path) != ECEX_OK) return ECEX_ERR;
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf) return ECEX_ERR;
+    size_t pos = 0;
+    for (size_t l = 1; l < target_line && pos < buf->len; pos++) {
+        if (buf->data[pos] == '\n') l++;
+    }
+    buffer_set_point(buf, pos);
+    return ECEX_OK;
+}
+
+static int ecex_append_shell_output(ecex_t *ed, const char *name, const char *command) {
+    if (!ed || !name || !command || !command[0]) return ECEX_ERR;
+    buffer_t *buf = ecex_create_interactive_buffer(ed, name);
+    if (!buf) return ECEX_ERR;
+    buffer_set_interactive(buf, 1);
+    if (buffer_clear(buf) != ECEX_OK) return ECEX_ERR;
+    buffer_set_interactive(buf, 1);
+    ecex_buffer_set_major_mode_by_name(ed, buf, "special-mode");
+
+    char header[2048];
+    snprintf(header, sizeof(header), "%s\n\nKeys: g/r rerun, n/p next/previous result, RET jump, q quit.\n\n", command);
+    buffer_append(buf, header);
+
+    char shell_command[4096];
+    snprintf(shell_command, sizeof(shell_command), "%s 2>&1", command);
+    FILE *pipe = popen(shell_command, "r");
+    if (!pipe) {
+        buffer_append(buf, "Failed to start command.\n");
+        return ecex_switch_buffer(ed, name);
+    }
+
+    char line[4096];
+    while (fgets(line, sizeof(line), pipe)) {
+        size_t len = strlen(line);
+        while (len > 0 && (line[len - 1] == '\n' || line[len - 1] == '\r')) line[--len] = '\0';
+        char path[1024];
+        size_t target = 0;
+        ecex_interactive_line_fn fn = NULL;
+        char payload[1200];
+        payload[0] = '\0';
+        if (ecex_parse_file_line(line, path, sizeof(path), &target) == ECEX_OK) {
+            snprintf(payload, sizeof(payload), "%s:%zu", path, target);
+            fn = ecex_goto_file_line_action;
+        }
+        ecex_interactive_append_line(ed, buf, line, fn, payload[0] ? payload : NULL, NULL);
+    }
+
+    int status = pclose(pipe);
+    char footer[128];
+    snprintf(footer, sizeof(footer), "\n[process exited: %d]\n", status);
+    buffer_append(buf, footer);
+    buf->point = 0;
+    buf->modified = 0;
+    return ecex_switch_buffer(ed, name);
+}
+
+int ecex_compile(ecex_t *ed, const char *command) {
+    if (!ed || !command || !command[0]) return ECEX_ERR;
+    if (ecex_set_owned_string(&ed->last_compile_command, command) != ECEX_OK) return ECEX_ERR;
+    return ecex_append_shell_output(ed, "*compilation*", command);
+}
+
+int ecex_grep(ecex_t *ed, const char *command) {
+    if (!ed || !command || !command[0]) return ECEX_ERR;
+    if (ecex_set_owned_string(&ed->last_grep_command, command) != ECEX_OK) return ECEX_ERR;
+    return ecex_append_shell_output(ed, "*grep*", command);
+}
+
+int ecex_rerun_compile(ecex_t *ed) {
+    if (!ed || !ed->last_compile_command) return ECEX_ERR;
+    return ecex_append_shell_output(ed, "*compilation*", ed->last_compile_command);
+}
+
+int ecex_rerun_grep(ecex_t *ed) {
+    if (!ed || !ed->last_grep_command) return ECEX_ERR;
+    return ecex_append_shell_output(ed, "*grep*", ed->last_grep_command);
+}
+
+int ecex_next_interactive_action(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf || !buffer_is_interactive(buf) || buf->interactive_action_count == 0) return ECEX_ERR;
+    size_t current = buffer_current_line_number(buf);
+    if (current > 0) current--;
+    size_t best = (size_t)-1;
+    for (size_t i = 0; i < buf->interactive_action_count; i++) {
+        size_t line = buf->interactive_actions[i].line;
+        if (line > current && (best == (size_t)-1 || line < best)) best = line;
+    }
+    if (best == (size_t)-1) best = buf->interactive_actions[0].line;
+    size_t pos = 0;
+    for (size_t l = 0; l < best && pos < buf->len; pos++) if (buf->data[pos] == '\n') l++;
+    buffer_set_point(buf, pos);
+    return ECEX_OK;
+}
+
+int ecex_previous_interactive_action(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf || !buffer_is_interactive(buf) || buf->interactive_action_count == 0) return ECEX_ERR;
+    size_t current = buffer_current_line_number(buf);
+    if (current > 0) current--;
+    size_t best = (size_t)-1;
+    for (size_t i = 0; i < buf->interactive_action_count; i++) {
+        size_t line = buf->interactive_actions[i].line;
+        if (line < current && (best == (size_t)-1 || line > best)) best = line;
+    }
+    if (best == (size_t)-1) best = buf->interactive_actions[buf->interactive_action_count - 1].line;
+    size_t pos = 0;
+    for (size_t l = 0; l < best && pos < buf->len; pos++) if (buf->data[pos] == '\n') l++;
+    buffer_set_point(buf, pos);
+    return ECEX_OK;
+}
+
+static int ecex_region_lines(buffer_t *buf, size_t *out_start, size_t *out_end) {
+    if (!buf || !buffer_has_selection(buf)) return ECEX_ERR;
+    size_t start = 0, end = 0;
+    buffer_selection_range(buf, &start, &end);
+    start = buffer_line_start_at(buf, start);
+    end = buffer_line_end_at(buf, end);
+    if (end < buf->len) end++;
+    if (out_start) *out_start = start;
+    if (out_end) *out_end = end;
+    return ECEX_OK;
+}
+
+int ecex_comment_region(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    size_t start = 0, end = 0;
+    if (!buf || ecex_region_lines(buf, &start, &end) != ECEX_OK) return ECEX_ERR;
+    size_t pos = start;
+    while (pos <= end && pos <= buf->len) {
+        if (buffer_insert_at(buf, pos, "// ") != ECEX_OK) return ECEX_ERR;
+        pos += 3;
+        end += 3;
+        size_t eol = buffer_line_end_at(buf, pos);
+        if (eol >= end || eol >= buf->len) break;
+        pos = eol + 1;
+    }
+    return ECEX_OK;
+}
+
+int ecex_uncomment_region(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    size_t start = 0, end = 0;
+    if (!buf || ecex_region_lines(buf, &start, &end) != ECEX_OK) return ECEX_ERR;
+    size_t pos = start;
+    while (pos < end && pos < buf->len) {
+        if (pos + 2 <= buf->len && memcmp(buf->data + pos, "//", 2) == 0) {
+            size_t del = (pos + 3 <= buf->len && buf->data[pos + 2] == ' ') ? 3 : 2;
+            if (buffer_delete_range(buf, pos, pos + del) != ECEX_OK) return ECEX_ERR;
+            end = end > del ? end - del : 0;
+        }
+        size_t eol = buffer_line_end_at(buf, pos);
+        if (eol >= end || eol >= buf->len) break;
+        pos = eol + 1;
+    }
+    return ECEX_OK;
+}
+
+int ecex_set_font(ecex_t *ed, const char *path) {
+    if (!ed || !path) return ECEX_ERR;
+
+    char *copy = ecex_strdup(path);
+    if (!copy) return ECEX_ERR;
+
+    free(ed->theme.font_path);
+    ed->theme.font_path = copy;
+    return ECEX_OK;
+}
+
+float ecex_get_font_size(ecex_t *ed) {
+    if (!ed) return 0.0f;
+    return ed->theme.font_size;
+}
+
+int ecex_set_font_size(ecex_t *ed, float size) {
+    if (!ed) return ECEX_ERR;
+    ed->theme.font_size = ECEX_CLAMP(size, 8.0f, 96.0f);
+    return ECEX_OK;
+}
+
+int ecex_adjust_font_size(ecex_t *ed, float delta) {
+    if (!ed) return ECEX_ERR;
+    return ecex_set_font_size(ed, ed->theme.font_size + delta);
+}
+
+void ecex_set_bg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.bg = ecex_color(r, g, b); }
+void ecex_set_fg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.fg = ecex_color(r, g, b); }
+void ecex_set_status_bg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.status_bg = ecex_color(r, g, b); }
+void ecex_set_status_fg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.status_fg = ecex_color(r, g, b); }
+void ecex_set_status_border_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.status_border = ecex_color(r, g, b); }
+void ecex_set_cursor_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.cursor = ecex_color(r, g, b); }
+void ecex_set_region_bg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.region_bg = ecex_color(r, g, b); }
+void ecex_set_minibuffer_bg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.minibuffer_bg = ecex_color(r, g, b); }
+void ecex_set_minibuffer_fg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.minibuffer_fg = ecex_color(r, g, b); }
+void ecex_set_completion_fg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.completion_fg = ecex_color(r, g, b); }
+void ecex_set_completion_enabled(ecex_t *ed, int enabled) { if (ed) ed->theme.completion_enabled = enabled ? 1 : 0; }
+void ecex_set_interactive_highlight_bg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.interactive_highlight_bg = ecex_color(r, g, b); }
+void ecex_set_interactive_highlight_fg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.interactive_highlight_fg = ecex_color(r, g, b); }
+void ecex_set_current_line_bg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.current_line_bg = ecex_color(r, g, b); }
+void ecex_set_search_bg_color(ecex_t *ed, float r, float g, float b) { if (ed) ed->theme.search_bg = ecex_color(r, g, b); }
+void ecex_set_line_numbers_enabled(ecex_t *ed, int enabled) { if (ed) ed->theme.line_numbers_enabled = enabled ? 1 : 0; }
+void ecex_set_current_line_enabled(ecex_t *ed, int enabled) { if (ed) ed->theme.current_line_enabled = enabled ? 1 : 0; }
diff --git a/src/eval.c b/src/eval.c
new file mode 100644
index 0000000..316d6d8
--- /dev/null
+++ b/src/eval.c
@@ -0,0 +1,482 @@
+#define _POSIX_C_SOURCE 200809L
+
+#include "eval.h"
+
+#include "buffers.h"
+#include "ccdjit.h"
+#include "common.h"
+#include "config.h"
+#include "ecex.h"
+#include "util.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+static ecex_t *g_eval_editor = NULL;
+
+static buffer_t *eval_output_buffer(ecex_t *ed) {
+    if (!ed) return NULL;
+
+    buffer_t *out = ecex_create_interactive_buffer(ed, "*eval-output*");
+    if (out) {
+        ecex_buffer_set_major_mode_by_name(ed, out, "eval-output-mode");
+    }
+
+    return out;
+}
+
+static void eval_append_diag(buffer_t *out, ccdjit_context *ctx) {
+    if (!out || !ctx) return;
+
+    const ccdjit_diagnostic *diag = ccdjit_context_last_error(ctx);
+    if (!diag) {
+        buffer_append(out, "ccdjit: unknown error\n");
+        return;
+    }
+
+    char line[1024];
+    snprintf(line,
+             sizeof(line),
+             "ccdjit error [%s] %s:%d:%d: %s\n",
+             diag->phase ? diag->phase : "?",
+             diag->filename ? diag->filename : "<input>",
+             diag->line,
+             diag->column,
+             diag->message ? diag->message : "(no message)");
+    buffer_append(out, line);
+
+    if (diag->source_line) {
+        buffer_append(out, diag->source_line);
+        buffer_append(out, "\n");
+    }
+
+    if (diag->caret_line) {
+        buffer_append(out, diag->caret_line);
+        buffer_append(out, "\n");
+    }
+}
+
+typedef struct eval_capture {
+    FILE *file;
+    int saved_stdout;
+    int saved_stderr;
+    int active;
+} eval_capture_t;
+
+static void eval_capture_init(eval_capture_t *capture) {
+    if (!capture) return;
+
+    capture->file = NULL;
+    capture->saved_stdout = -1;
+    capture->saved_stderr = -1;
+    capture->active = 0;
+}
+
+static int eval_capture_begin(eval_capture_t *capture, buffer_t *out) {
+    if (!capture) return ECEX_ERR;
+
+    eval_capture_init(capture);
+
+    capture->file = tmpfile();
+    if (!capture->file) {
+        if (out) buffer_append(out, "warning: failed to create stdout capture file\n");
+        return ECEX_ERR;
+    }
+
+    int capture_fd = fileno(capture->file);
+    if (capture_fd < 0) {
+        if (out) buffer_append(out, "warning: failed to get stdout capture fd\n");
+        fclose(capture->file);
+        eval_capture_init(capture);
+        return ECEX_ERR;
+    }
+
+    fflush(NULL);
+
+    capture->saved_stdout = dup(STDOUT_FILENO);
+    capture->saved_stderr = dup(STDERR_FILENO);
+
+    if (capture->saved_stdout < 0 || capture->saved_stderr < 0) {
+        if (out) buffer_append(out, "warning: failed to save stdout/stderr\n");
+
+        if (capture->saved_stdout >= 0) close(capture->saved_stdout);
+        if (capture->saved_stderr >= 0) close(capture->saved_stderr);
+        fclose(capture->file);
+        eval_capture_init(capture);
+        return ECEX_ERR;
+    }
+
+    if (dup2(capture_fd, STDOUT_FILENO) < 0 ||
+        dup2(capture_fd, STDERR_FILENO) < 0) {
+        if (out) buffer_append(out, "warning: failed to redirect stdout/stderr\n");
+
+        dup2(capture->saved_stdout, STDOUT_FILENO);
+        dup2(capture->saved_stderr, STDERR_FILENO);
+        close(capture->saved_stdout);
+        close(capture->saved_stderr);
+        fclose(capture->file);
+        eval_capture_init(capture);
+        return ECEX_ERR;
+    }
+
+    capture->active = 1;
+    return ECEX_OK;
+}
+
+static void eval_capture_restore(eval_capture_t *capture) {
+    if (!capture || !capture->active) return;
+
+    fflush(NULL);
+
+    if (capture->saved_stdout >= 0) {
+        dup2(capture->saved_stdout, STDOUT_FILENO);
+        close(capture->saved_stdout);
+        capture->saved_stdout = -1;
+    }
+
+    if (capture->saved_stderr >= 0) {
+        dup2(capture->saved_stderr, STDERR_FILENO);
+        close(capture->saved_stderr);
+        capture->saved_stderr = -1;
+    }
+
+    capture->active = 0;
+}
+
+static void eval_capture_append_output(eval_capture_t *capture, buffer_t *out) {
+    if (!capture || !capture->file || !out) return;
+
+    if (fseek(capture->file, 0, SEEK_END) != 0) {
+        return;
+    }
+
+    long size = ftell(capture->file);
+    if (size <= 0) {
+        return;
+    }
+
+    if (fseek(capture->file, 0, SEEK_SET) != 0) {
+        return;
+    }
+
+    buffer_append(out, "stdout/stderr:\n");
+
+    char chunk[4096];
+    size_t n = 0;
+
+    while ((n = fread(chunk, 1, sizeof(chunk), capture->file)) > 0) {
+        size_t old_len = out->len;
+
+        if (buffer_reserve(out, out->len + n + 1) != ECEX_OK) {
+            buffer_append(out, "\n[output truncated: allocation failed]\n");
+            return;
+        }
+
+        memcpy(out->data + old_len, chunk, n);
+        out->len += n;
+        out->data[out->len] = '\0';
+        out->point = out->len;
+    }
+
+    if (out->len > 0 && out->data[out->len - 1] != '\n') {
+        buffer_append(out, "\n");
+    }
+
+    buffer_append(out, "\n");
+}
+
+static void eval_capture_finish(eval_capture_t *capture, buffer_t *out) {
+    if (!capture) return;
+
+    eval_capture_restore(capture);
+    eval_capture_append_output(capture, out);
+
+    if (capture->file) {
+        fclose(capture->file);
+    }
+
+    eval_capture_init(capture);
+}
+
+static int source_has_main(const char *source) {
+    if (!source) return 0;
+
+    return strstr(source, "main(") != NULL ||
+           strstr(source, "main (") != NULL;
+}
+
+static char *make_eval_source(const char *source, int wrap_as_statements) {
+    if (!source) return NULL;
+
+    const char *prefix =
+        "#include \"ecex.h\"\n"
+        "#include \"buffers.h\"\n"
+        "extern ecex_t *__ecex_eval_editor;\n"
+        "#define ECEX_ED (__ecex_eval_editor)\n"
+        "\n";
+
+    const char *wrapper_open =
+        "int main(int argc, char **argv) {\n"
+        "    (void)argc;\n"
+        "    (void)argv;\n"
+        "    ecex_t *ed = __ecex_eval_editor;\n"
+        "    (void)ed;\n";
+
+    const char *wrapper_close =
+        "\n"
+        "    return 0;\n"
+        "}\n";
+
+    int do_wrap = wrap_as_statements || !source_has_main(source);
+
+    size_t prefix_len = strlen(prefix);
+    size_t source_len = strlen(source);
+    size_t open_len = do_wrap ? strlen(wrapper_open) : 0;
+    size_t close_len = do_wrap ? strlen(wrapper_close) : 0;
+
+    char *combined = malloc(prefix_len + open_len + source_len + close_len + 2);
+    if (!combined) return NULL;
+
+    char *p = combined;
+    memcpy(p, prefix, prefix_len);
+    p += prefix_len;
+
+    if (do_wrap) {
+        memcpy(p, wrapper_open, open_len);
+        p += open_len;
+    }
+
+    memcpy(p, source, source_len);
+    p += source_len;
+
+    if (do_wrap) {
+        if (source_len == 0 || source[source_len - 1] != '\n') {
+            *p++ = '\n';
+        }
+        memcpy(p, wrapper_close, close_len);
+        p += close_len;
+    }
+
+    *p = '\0';
+    return combined;
+}
+
+static int remember_last_eval(ecex_t *ed,
+                              const char *source,
+                              const char *filename,
+                              int wrap_as_statements) {
+    if (!ed || !source) return ECEX_ERR;
+
+    char *source_copy = ecex_strdup(source);
+    char *filename_copy = ecex_strdup(filename ? filename : "<eval>");
+    if (!source_copy || !filename_copy) {
+        free(source_copy);
+        free(filename_copy);
+        return ECEX_ERR;
+    }
+
+    free(ed->last_eval_source);
+    free(ed->last_eval_filename);
+    ed->last_eval_source = source_copy;
+    ed->last_eval_filename = filename_copy;
+    ed->last_eval_wrap_as_statements = wrap_as_statements;
+    return ECEX_OK;
+}
+
+int ecex_eval_source(ecex_t *ed,
+                     const char *source,
+                     const char *filename,
+                     int wrap_as_statements) {
+    if (!ed || !source) return ECEX_ERR;
+
+    remember_last_eval(ed, source, filename, wrap_as_statements);
+
+    buffer_t *out = eval_output_buffer(ed);
+    if (!out) return ECEX_ERR;
+
+    buffer_clear(out);
+    buffer_set_interactive(out, 1);
+    ecex_buffer_set_major_mode_by_name(ed, out, "eval-output-mode");
+    buffer_append(out, "Eval output (g: re-eval, q: quit window, ENTER: follow line if available)\n");
+    buffer_append(out, "────────────────────────────────────────────────────────────────\n\n");
+    buffer_append(out, "Eval: ");
+    buffer_append(out, filename ? filename : "<eval>");
+    buffer_append(out, "\n\n");
+
+    char *eval_source = make_eval_source(source, wrap_as_statements);
+    if (!eval_source) {
+        buffer_append(out, "failed to allocate eval source\n");
+        ecex_switch_buffer(ed, "*eval-output*");
+        return ECEX_ERR;
+    }
+
+    ccdjit_context *ctx = ccdjit_context_new(NULL);
+    if (!ctx) {
+        buffer_append(out, "failed to create ccdjit context\n");
+        free(eval_source);
+        ecex_switch_buffer(ed, "*eval-output*");
+        return ECEX_ERR;
+    }
+
+    if (ecex_add_ccdjit_include_paths(ctx) != ECEX_OK ||
+        ecex_register_host_symbols(ctx) != ECEX_OK ||
+        ccdjit_context_register_symbol(ctx,
+                                       "__ecex_eval_editor",
+                                       (void *)&g_eval_editor) != 0) {
+        buffer_append(out, "failed to prepare eval context\n");
+        eval_append_diag(out, ctx);
+        ccdjit_context_free(ctx);
+        free(eval_source);
+        ecex_switch_buffer(ed, "*eval-output*");
+        return ECEX_ERR;
+    }
+
+    g_eval_editor = ed;
+
+    ccdjit_module *module = NULL;
+    if (ccdjit_compile_string(ctx,
+                              eval_source,
+                              filename ? filename : "<eval>",
+                              &module) != 0) {
+        buffer_append(out, "compile failed\n\n");
+        eval_append_diag(out, ctx);
+        g_eval_editor = NULL;
+        ccdjit_context_free(ctx);
+        free(eval_source);
+        ecex_switch_buffer(ed, "*eval-output*");
+        return ECEX_ERR;
+    }
+
+    int result = 0;
+    eval_capture_t capture;
+    int capture_enabled = (eval_capture_begin(&capture, out) == ECEX_OK);
+    int runtime_status = ccdjit_module_call_main(module, 0, NULL, &result);
+
+    if (capture_enabled) {
+        eval_capture_finish(&capture, out);
+    }
+
+    if (runtime_status != 0) {
+        buffer_append(out, "runtime failed\n\n");
+        eval_append_diag(out, ctx);
+        ccdjit_module_free(module);
+        g_eval_editor = NULL;
+        ccdjit_context_free(ctx);
+        free(eval_source);
+        ecex_switch_buffer(ed, "*eval-output*");
+        return ECEX_ERR;
+    }
+
+    char line[128];
+    snprintf(line, sizeof(line), "ok, result = %d\n", result);
+    buffer_append(out, line);
+
+    /*
+     * Keep successful eval modules alive.  This makes eval useful for live
+     * customization: code evaluated from a buffer may register commands whose
+     * function pointers remain valid after eval returns.
+     */
+    if (ecex_keep_jit_module(ed, module) != ECEX_OK) {
+        buffer_append(out, "failed to keep eval module alive\n");
+        ccdjit_module_free(module);
+        g_eval_editor = NULL;
+        ccdjit_context_free(ctx);
+        free(eval_source);
+        ecex_switch_buffer(ed, "*eval-output*");
+        return ECEX_ERR;
+    }
+
+    g_eval_editor = NULL;
+    ccdjit_context_free(ctx);
+    free(eval_source);
+
+    out->modified = 0;
+    out->point = 0;
+    ecex_switch_buffer(ed, "*eval-output*");
+    return ECEX_OK;
+}
+
+int ecex_eval_current_buffer(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf || !buf->data) return ECEX_ERR;
+
+    return ecex_eval_source(ed,
+                            buf->data,
+                            buf->path ? buf->path : buf->name,
+                            0);
+}
+
+int ecex_eval_current_line(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf) return ECEX_ERR;
+
+    char *line = buffer_current_line_copy(buf);
+    if (!line) return ECEX_ERR;
+
+    int result = ecex_eval_source(ed, line, "<current-line>", 1);
+    free(line);
+    return result;
+}
+
+
+int ecex_eval_current_region(ecex_t *ed) {
+    buffer_t *buf = ecex_current_buffer(ed);
+    if (!buf || !buffer_has_selection(buf)) return ECEX_ERR;
+
+    size_t start = 0;
+    size_t end = 0;
+    buffer_selection_range(buf, &start, &end);
+
+    char *region = buffer_substring(buf, start, end);
+    if (!region) return ECEX_ERR;
+
+    int result = ecex_eval_source(ed, region, "<region>", 1);
+    free(region);
+    return result;
+}
+
+int ecex_eval_file(ecex_t *ed, const char *path) {
+    if (!ed || !path || !path[0]) return ECEX_ERR;
+
+    size_t size = 0;
+    char *source = ecex_read_entire_file(path, &size);
+    (void)size;
+
+    if (!source) {
+        buffer_t *out = eval_output_buffer(ed);
+        if (out) {
+            buffer_clear(out);
+            buffer_append(out, "failed to read eval file: ");
+            buffer_append(out, path);
+            buffer_append(out, "\n");
+            out->modified = 0;
+            ecex_switch_buffer(ed, "*eval-output*");
+        }
+        return ECEX_ERR;
+    }
+
+    int result = ecex_eval_source(ed, source, path, 0);
+    free(source);
+    return result;
+}
+
+int ecex_eval_rerun_last(ecex_t *ed) {
+    if (!ed || !ed->last_eval_source) return ECEX_ERR;
+
+    char *source = ecex_strdup(ed->last_eval_source);
+    char *filename = ecex_strdup(ed->last_eval_filename ? ed->last_eval_filename : "<eval>");
+    int wrap = ed->last_eval_wrap_as_statements;
+
+    if (!source || !filename) {
+        free(source);
+        free(filename);
+        return ECEX_ERR;
+    }
+
+    int result = ecex_eval_source(ed, source, filename, wrap);
+    free(source);
+    free(filename);
+    return result;
+}
diff --git a/src/font.c b/src/font.c
new file mode 100644
index 0000000..62985e4
--- /dev/null
+++ b/src/font.c
@@ -0,0 +1,258 @@
+#include "font.h"
+#include "util.h"
+
+#define STB_TRUETYPE_IMPLEMENTATION
+#include "stb_truetype.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+const char *font_choose_path(const char *explicit_font_path) {
+    static char candidate[4096];
+
+    if (explicit_font_path && explicit_font_path[0]) {
+        return explicit_font_path;
+    }
+
+    const char *env_font = getenv("ECEX_FONT");
+    if (env_font && env_font[0]) {
+        return env_font;
+    }
+
+    const char *guix_env = getenv("GUIX_ENVIRONMENT");
+    if (guix_env && guix_env[0]) {
+        snprintf(candidate, sizeof(candidate),
+                 "%s/share/fonts/truetype/DejaVuSansMono.ttf", guix_env);
+        if (ecex_file_exists(candidate)) return candidate;
+
+        snprintf(candidate, sizeof(candidate),
+                 "%s/share/fonts/truetype/dejavu/DejaVuSansMono.ttf", guix_env);
+        if (ecex_file_exists(candidate)) return candidate;
+
+        snprintf(candidate, sizeof(candidate),
+                 "%s/share/fonts/dejavu/DejaVuSansMono.ttf", guix_env);
+        if (ecex_file_exists(candidate)) return candidate;
+    }
+
+    const char *home = getenv("HOME");
+    if (home && home[0]) {
+        snprintf(candidate, sizeof(candidate),
+                 "%s/.guix-profile/share/fonts/truetype/DejaVuSansMono.ttf", home);
+        if (ecex_file_exists(candidate)) return candidate;
+
+        snprintf(candidate, sizeof(candidate),
+                 "%s/.guix-profile/share/fonts/truetype/dejavu/DejaVuSansMono.ttf", home);
+        if (ecex_file_exists(candidate)) return candidate;
+
+        snprintf(candidate, sizeof(candidate),
+                 "%s/.guix-profile/share/fonts/dejavu/DejaVuSansMono.ttf", home);
+        if (ecex_file_exists(candidate)) return candidate;
+    }
+
+    if (ecex_file_exists("/usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf")) {
+        return "/usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf";
+    }
+
+    if (ecex_file_exists("/usr/share/fonts/TTF/DejaVuSansMono.ttf")) {
+        return "/usr/share/fonts/TTF/DejaVuSansMono.ttf";
+    }
+
+    return NULL;
+}
+
+int font_load(font_t *font, const char *path, float size_px) {
+    if (!font || !path) return -1;
+
+    memset(font, 0, sizeof(*font));
+
+    size_t ttf_size = 0;
+    char *ttf_data = ecex_read_entire_file(path, &ttf_size);
+    if (!ttf_data) {
+        fprintf(stderr, "failed to read font: %s\n", path);
+        return -1;
+    }
+
+    unsigned char *bitmap = calloc(1, ECEX_FONT_BITMAP_W * ECEX_FONT_BITMAP_H);
+    if (!bitmap) {
+        free(ttf_data);
+        return -1;
+    }
+
+    stbtt_fontinfo info;
+    int ascent = 0;
+    int descent = 0;
+    int line_gap = 0;
+
+    if (stbtt_InitFont(&info, (const unsigned char *)ttf_data, 0)) {
+        float scale = stbtt_ScaleForPixelHeight(&info, size_px);
+        stbtt_GetFontVMetrics(&info, &ascent, &descent, &line_gap);
+
+        font->ascent_px = (float)ascent * scale;
+        font->descent_px = (float)(-descent) * scale;
+        font->line_gap_px = (float)line_gap * scale;
+    }
+
+    if (font->ascent_px <= 0.0f) {
+        font->ascent_px = size_px * 0.80f;
+    }
+
+    if (font->descent_px <= 0.0f) {
+        font->descent_px = size_px * 0.20f;
+    }
+
+    if (font->line_gap_px < 0.0f) {
+        font->line_gap_px = 0.0f;
+    }
+
+    int bake_result = stbtt_BakeFontBitmap(
+        (const unsigned char *)ttf_data,
+        0,
+        size_px,
+        bitmap,
+        ECEX_FONT_BITMAP_W,
+        ECEX_FONT_BITMAP_H,
+        ECEX_FONT_FIRST_CHAR,
+        ECEX_FONT_CHAR_COUNT,
+        font->chars
+    );
+
+    free(ttf_data);
+
+    if (bake_result <= 0) {
+        fprintf(stderr, "failed to bake font atlas from: %s\n", path);
+        free(bitmap);
+        return -1;
+    }
+
+    glGenTextures(1, &font->texture);
+    glBindTexture(GL_TEXTURE_2D, font->texture);
+
+    glTexImage2D(GL_TEXTURE_2D,
+                 0,
+                 GL_ALPHA,
+                 ECEX_FONT_BITMAP_W,
+                 ECEX_FONT_BITMAP_H,
+                 0,
+                 GL_ALPHA,
+                 GL_UNSIGNED_BYTE,
+                 bitmap);
+
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+    free(bitmap);
+
+    font->size_px = size_px;
+    font->line_height = font->ascent_px + font->descent_px + font->line_gap_px;
+
+    if (font->line_height < size_px * 1.15f) {
+        font->line_height = size_px * 1.15f;
+    }
+
+    fprintf(stderr, "ecex: loaded font: %s\n", path);
+    return 0;
+}
+
+void font_free(font_t *font) {
+    if (!font) return;
+
+    if (font->texture) {
+        glDeleteTextures(1, &font->texture);
+        font->texture = 0;
+    }
+}
+
+void draw_text(font_t *font, float x, float y, const char *text) {
+    if (!font || !font->texture || !text) return;
+
+    glEnable(GL_TEXTURE_2D);
+    glBindTexture(GL_TEXTURE_2D, font->texture);
+
+    glBegin(GL_QUADS);
+
+    float start_x = x;
+
+    for (const char *p = text; *p; p++) {
+        unsigned char c = (unsigned char)*p;
+
+        if (c == '\n') {
+            x = start_x;
+            y += font->line_height;
+            continue;
+        }
+
+        if (c == '\t') {
+            x += font->size_px * 4.0f;
+            continue;
+        }
+
+        if (c < ECEX_FONT_FIRST_CHAR ||
+            c >= ECEX_FONT_FIRST_CHAR + ECEX_FONT_CHAR_COUNT) {
+            c = '?';
+        }
+
+        stbtt_aligned_quad q;
+
+        stbtt_GetBakedQuad(font->chars,
+                           ECEX_FONT_BITMAP_W,
+                           ECEX_FONT_BITMAP_H,
+                           c - ECEX_FONT_FIRST_CHAR,
+                           &x,
+                           &y,
+                           &q,
+                           1);
+
+        glTexCoord2f(q.s0, q.t0);
+        glVertex2f(q.x0, q.y0);
+
+        glTexCoord2f(q.s1, q.t0);
+        glVertex2f(q.x1, q.y0);
+
+        glTexCoord2f(q.s1, q.t1);
+        glVertex2f(q.x1, q.y1);
+
+        glTexCoord2f(q.s0, q.t1);
+        glVertex2f(q.x0, q.y1);
+    }
+
+    glEnd();
+
+    glDisable(GL_TEXTURE_2D);
+}
+
+float text_width(font_t *font, const char *text) {
+    if (!font || !text) return 0.0f;
+
+    float x = 0.0f;
+    float y = 0.0f;
+
+    for (const char *p = text; *p; p++) {
+        unsigned char c = (unsigned char)*p;
+
+        if (c == '\n') break;
+
+        if (c == '\t') {
+            x += font->size_px * 4.0f;
+            continue;
+        }
+
+        if (c < ECEX_FONT_FIRST_CHAR ||
+            c >= ECEX_FONT_FIRST_CHAR + ECEX_FONT_CHAR_COUNT) {
+            c = '?';
+        }
+
+        stbtt_aligned_quad q;
+
+        stbtt_GetBakedQuad(font->chars,
+                           ECEX_FONT_BITMAP_W,
+                           ECEX_FONT_BITMAP_H,
+                           c - ECEX_FONT_FIRST_CHAR,
+                           &x,
+                           &y,
+                           &q,
+                           1);
+    }
+
+    return x;
+}
diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..9f388a0
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,164 @@
+#include "app.h"
+#include "config.h"
+#include "font.h"
+#include "render.h"
+
+#include <GLFW/glfw3.h>
+
+#include <stdio.h>
+#include <string.h>
+
+#define WINDOW_WIDTH 1000
+#define WINDOW_HEIGHT 700
+
+static void print_usage(const char *argv0) {
+    fprintf(stderr, "usage:\n");
+    fprintf(stderr, "  %s [--config path/to/ecexrc.c] [--font path/to/font.ttf]\n", argv0);
+    fprintf(stderr, "\n");
+    fprintf(stderr, "keys:\n");
+    fprintf(stderr, "  F1 opens M-x\n");
+    fprintf(stderr, "  Tab completes M-x command names\n");
+    fprintf(stderr, "  Alt+x opens M-x when the OS/window-manager allows it\n");
+    fprintf(stderr, "  C-x is reserved for prefix maps\n");
+    fprintf(stderr, "\n");
+    fprintf(stderr, "env:\n");
+    fprintf(stderr, "  ECEX_FONT=/path/to/font.ttf\n");
+    fprintf(stderr, "  ECEX_INCLUDE=/path/to/ecex/include\n");
+}
+
+static int parse_args(int argc,
+                      char **argv,
+                      const char **config_path,
+                      const char **font_path_arg) {
+    *config_path = NULL;
+    *font_path_arg = NULL;
+
+    for (int i = 1; i < argc; i++) {
+        if (strcmp(argv[i], "--config") == 0) {
+            if (i + 1 >= argc) {
+                print_usage(argv[0]);
+                return -1;
+            }
+
+            *config_path = argv[++i];
+        } else if (strcmp(argv[i], "--font") == 0) {
+            if (i + 1 >= argc) {
+                print_usage(argv[0]);
+                return -1;
+            }
+
+            *font_path_arg = argv[++i];
+        } else if (strcmp(argv[i], "--help") == 0 ||
+                   strcmp(argv[i], "-h") == 0) {
+            print_usage(argv[0]);
+            return 1;
+        } else {
+            *font_path_arg = argv[i];
+        }
+    }
+
+    return 0;
+}
+
+static const char *select_font_path(ecex_t *ed, const char *font_path_arg) {
+    if (font_path_arg) return font_path_arg;
+    if (ed && ed->theme.font_path) return ed->theme.font_path;
+    return font_choose_path(NULL);
+}
+
+int main(int argc, char **argv) {
+    const char *config_path = NULL;
+    const char *font_path_arg = NULL;
+
+    int args_result = parse_args(argc, argv, &config_path, &font_path_arg);
+    if (args_result != 0) {
+        return args_result < 0 ? 1 : 0;
+    }
+
+    ecex_t *ed = ecex_new();
+    if (!ed) {
+        fprintf(stderr, "failed to create editor\n");
+        return 1;
+    }
+
+    if (config_path) {
+        if (ecex_load_c_config(ed, config_path) != 0) {
+            fprintf(stderr, "ecex: continuing without config\n");
+        }
+    }
+
+    if (!glfwInit()) {
+        fprintf(stderr, "failed to initialize GLFW\n");
+        ecex_free(ed);
+        return 1;
+    }
+
+    GLFWwindow *window = glfwCreateWindow(
+        WINDOW_WIDTH,
+        WINDOW_HEIGHT,
+        "ecex",
+        NULL,
+        NULL
+    );
+
+    if (!window) {
+        fprintf(stderr, "failed to create GLFW window\n");
+        glfwTerminate();
+        ecex_free(ed);
+        return 1;
+    }
+
+    glfwMakeContextCurrent(window);
+    glfwSwapInterval(1);
+
+    app_t app;
+    app_init(&app, ed);
+    app_set_window(&app, window);
+
+    const char *font_path = select_font_path(ed, font_path_arg);
+    if (!font_path) {
+        fprintf(stderr, "ecex: could not find a font automatically\n");
+        fprintf(stderr, "try:\n");
+        fprintf(stderr, "  export ECEX_FONT=/path/to/font.ttf\n");
+        fprintf(stderr, "  %s --font /path/to/font.ttf\n", argv[0]);
+
+        glfwDestroyWindow(window);
+        glfwTerminate();
+        ecex_free(ed);
+        return 1;
+    }
+
+    if (font_load(&app.font, font_path, ed->theme.font_size) != 0) {
+        fprintf(stderr, "ecex: could not load font\n");
+        fprintf(stderr, "try an explicit font path:\n");
+        fprintf(stderr, "  %s --font /path/to/font.ttf\n", argv[0]);
+
+        glfwDestroyWindow(window);
+        glfwTerminate();
+        ecex_free(ed);
+        return 1;
+    }
+
+    snprintf(app.font_path, sizeof(app.font_path), "%s", font_path);
+
+    app_install_callbacks(&app);
+    app_message(&app, "F1 for M-x. Tab completes commands.");
+
+    while (!glfwWindowShouldClose(window) && !ed->should_quit) {
+        if (app.dirty) {
+            render(&app);
+            glfwSwapBuffers(window);
+            app.dirty = 0;
+        }
+
+        glfwWaitEvents();
+    }
+
+    font_free(&app.font);
+
+    glfwDestroyWindow(window);
+    glfwTerminate();
+
+    ecex_free(ed);
+    return 0;
+}
diff --git a/src/render.c b/src/render.c
new file mode 100644
index 0000000..64a85f1
--- /dev/null
+++ b/src/render.c
@@ -0,0 +1,613 @@
+#include "render.h"
+
+#include "common.h"
+
+#include <GLFW/glfw3.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * All UI measurements are derived from the active font.  draw_text() uses a
+ * baseline y coordinate, so render.c keeps both line-top and baseline values
+ * explicit.  This avoids the old fixed 24/28/34 pixel constants drifting when
+ * font size changes.
+ */
+typedef struct view_rect {
+    float x;
+    float y;
+    float w;
+    float h;
+} view_rect_t;
+
+typedef struct ui_metrics {
+    float pad_x;
+    float pad_y;
+
+    float content_x;
+    float content_top;
+    float content_bottom_pad;
+
+    float status_h;
+    float minibuffer_h;
+
+    float cursor_w;
+    float cursor_h;
+} ui_metrics_t;
+
+static float ecex_maxf(float a, float b) {
+    return a > b ? a : b;
+}
+
+static ui_metrics_t ui_metrics(app_t *app) {
+    float size = app && app->font.size_px > 1.0f ? app->font.size_px : 16.0f;
+    float line_h = app && app->font.line_height > 1.0f
+        ? app->font.line_height
+        : size * 1.20f;
+
+    ui_metrics_t m;
+
+    m.pad_x = ecex_maxf(8.0f, size * 0.75f);
+    m.pad_y = ecex_maxf(4.0f, size * 0.35f);
+
+    m.content_x = m.pad_x;
+    m.content_top = m.pad_y;
+    m.content_bottom_pad = m.pad_y;
+
+    m.status_h = line_h + m.pad_y * 2.0f;
+    m.minibuffer_h = line_h + m.pad_y * 2.0f;
+
+    m.cursor_w = ecex_maxf(2.0f, size * 0.10f);
+    m.cursor_h = ecex_maxf(1.0f, app ? app->font.ascent_px + app->font.descent_px : size);
+
+    return m;
+}
+
+static float line_baseline(app_t *app, float line_top) {
+    float ascent = app->font.ascent_px > 1.0f
+        ? app->font.ascent_px
+        : app->font.size_px * 0.80f;
+
+    return line_top + ascent;
+}
+
+static void setup_2d(int width, int height) {
+    glViewport(0, 0, width, height);
+
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+    glOrtho(0, width, height, 0, -1, 1);
+
+    glMatrixMode(GL_MODELVIEW);
+    glLoadIdentity();
+}
+
+static void draw_rect(float x, float y, float w, float h) {
+    glBegin(GL_QUADS);
+    glVertex2f(x, y);
+    glVertex2f(x + w, y);
+    glVertex2f(x + w, y + h);
+    glVertex2f(x, y + h);
+    glEnd();
+}
+
+static float mono_cell_width(app_t *app) {
+    float w = text_width(&app->font, "M");
+    return w > 1.0f ? w : app->font.size_px * 0.6f;
+}
+
+static int minibuffer_visible(app_t *app) {
+    return app->mode == APP_MODE_MX ||
+           app->mode == APP_MODE_PREFIX ||
+           app->mode == APP_MODE_PROMPT ||
+           app->mode == APP_MODE_ISEARCH ||
+           app->message[0] != '\0';
+}
+
+static size_t visible_row_count_for_rect(app_t *app, view_rect_t r) {
+    ui_metrics_t m = ui_metrics(app);
+    float usable = r.h - m.content_top - m.content_bottom_pad;
+
+    if (usable <= app->font.line_height || app->font.line_height <= 1.0f) {
+        return 1;
+    }
+
+    size_t rows = (size_t)(usable / app->font.line_height);
+    return rows ? rows : 1;
+}
+
+static float gutter_width(app_t *app, buffer_t *buf) {
+    if (!app || !app->ed || !buf || !app->ed->theme.line_numbers_enabled) return 0.0f;
+    char tmp[32];
+    snprintf(tmp, sizeof(tmp), "%zu ", buffer_line_count(buf));
+    return text_width(&app->font, tmp) + ui_metrics(app).pad_x * 0.5f;
+}
+
+static size_t visible_col_count_for_rect(app_t *app, view_rect_t r) {
+    ui_metrics_t m = ui_metrics(app);
+    float cell = mono_cell_width(app);
+    buffer_t *buf = ecex_current_buffer(app->ed);
+    float width = r.w - m.content_x * 2.0f - gutter_width(app, buf);
+
+    if (width <= cell) return 1;
+    return (size_t)(width / cell);
+}
+
+static size_t offset_for_line(buffer_t *buf, size_t target_line) {
+    if (!buf || target_line == 0) return 0;
+
+    size_t line = 0;
+    for (size_t i = 0; i < buf->len; i++) {
+        if (buf->data[i] == '\n') {
+            line++;
+            if (line == target_line) {
+                return i + 1;
+            }
+        }
+    }
+
+    return buf->len;
+}
+
+static void ensure_cursor_visible(app_t *app, buffer_t *buf, view_rect_t rect) {
+    if (!app || !buf) return;
+
+    size_t rows = visible_row_count_for_rect(app, rect);
+    size_t cols = visible_col_count_for_rect(app, rect);
+
+    size_t cursor_line = buffer_current_line_number(buf);
+    if (cursor_line > 0) cursor_line--;
+
+    size_t cursor_col = buffer_current_column(buf);
+
+    if (cursor_line < buf->scroll_line) {
+        buf->scroll_line = cursor_line;
+    } else if (cursor_line >= buf->scroll_line + rows) {
+        buf->scroll_line = cursor_line - rows + 1;
+    }
+
+    if (cursor_col < buf->scroll_col) {
+        buf->scroll_col = cursor_col;
+    } else if (cursor_col >= buf->scroll_col + cols) {
+        buf->scroll_col = cursor_col - cols + 1;
+    }
+}
+
+static void render_status_bar(app_t *app) {
+    buffer_t *buf = ecex_current_buffer(app->ed);
+    if (!buf) return;
+
+    ui_metrics_t m = ui_metrics(app);
+    float y = (float)app->height - m.status_h;
+    float text_x = m.pad_x;
+    float text_y = line_baseline(app, y + m.pad_y);
+
+    glDisable(GL_TEXTURE_2D);
+
+    glColor3f(app->ed->theme.status_bg.r,
+              app->ed->theme.status_bg.g,
+              app->ed->theme.status_bg.b);
+    draw_rect(0.0f, y, (float)app->width, m.status_h);
+
+    glColor3f(app->ed->theme.status_border.r,
+              app->ed->theme.status_border.g,
+              app->ed->theme.status_border.b);
+    draw_rect(0.0f, y, (float)app->width, 1.0f);
+
+    char status[768];
+    snprintf(status,
+             sizeof(status),
+             " %s%s   %s   line:%zu col:%zu   top:%zu   size:%zu   buffers:%zu   windows:%zu   commands:%zu%s%s",
+             buf->name ? buf->name : "(unnamed)",
+             buf->modified ? " *" : "",
+             ecex_buffer_major_mode_name(app->ed, buf),
+             buffer_current_line_number(buf),
+             buffer_current_column(buf),
+             buf->scroll_line + 1,
+             buf->len,
+             app->ed->buffer_count,
+             ecex_window_count(app->ed),
+             app->ed->command_count,
+             buf->path ? "   " : "",
+             buf->path ? buf->path : "");
+
+    glColor3f(app->ed->theme.status_fg.r,
+              app->ed->theme.status_fg.g,
+              app->ed->theme.status_fg.b);
+    draw_text(&app->font, text_x, text_y, status);
+}
+
+static void render_command_completion(app_t *app,
+                                      const char *line,
+                                      float x,
+                                      float y) {
+    const char *completion = ecex_complete_command(app->ed, app->minibuffer);
+    if (!completion || !completion[0]) return;
+
+    size_t input_len = strlen(app->minibuffer);
+    if (input_len == 0) return;
+
+    float ghost_x = x + text_width(&app->font, line);
+
+    glColor3f(app->ed->theme.completion_fg.r,
+              app->ed->theme.completion_fg.g,
+              app->ed->theme.completion_fg.b);
+
+    if (strncmp(completion, app->minibuffer, input_len) == 0 &&
+        completion[input_len] != '\0') {
+        draw_text(&app->font, ghost_x, y, completion + input_len);
+    } else if (strcmp(completion, app->minibuffer) != 0) {
+        char hint[ECEX_MINIBUFFER_SIZE + 16];
+        snprintf(hint, sizeof(hint), "  -> %s", completion);
+        draw_text(&app->font, ghost_x, y, hint);
+    }
+}
+
+static void render_minibuffer(app_t *app) {
+    if (!minibuffer_visible(app)) {
+        return;
+    }
+
+    ui_metrics_t m = ui_metrics(app);
+    float h = m.minibuffer_h;
+    float y = (float)app->height - m.status_h - h;
+    float text_x = m.pad_x;
+    float text_y = line_baseline(app, y + m.pad_y);
+
+    glDisable(GL_TEXTURE_2D);
+
+    glColor3f(app->ed->theme.minibuffer_bg.r,
+              app->ed->theme.minibuffer_bg.g,
+              app->ed->theme.minibuffer_bg.b);
+    draw_rect(0.0f, y, (float)app->width, h);
+
+    glColor3f(app->ed->theme.minibuffer_fg.r,
+              app->ed->theme.minibuffer_fg.g,
+              app->ed->theme.minibuffer_fg.b);
+
+    if (app->mode == APP_MODE_ISEARCH) {
+        char line[ECEX_MINIBUFFER_SIZE + 64];
+        snprintf(line,
+                 sizeof(line),
+                 "%s%s%s",
+                 app->isearch_backward ? "I-search backward: " : "I-search: ",
+                 app->isearch_query,
+                 app->isearch_has_match || app->isearch_len == 0 ? "" : " [failing]");
+        draw_text(&app->font, text_x, text_y, line);
+    } else if (app->mode == APP_MODE_MX) {
+        char line[ECEX_MINIBUFFER_SIZE + 8];
+        snprintf(line, sizeof(line), "M-x %s", app->minibuffer);
+
+        draw_text(&app->font, text_x, text_y, line);
+        render_command_completion(app, line, text_x, text_y);
+    } else if (app->mode == APP_MODE_PROMPT) {
+        char line[1200];
+        snprintf(line,
+                 sizeof(line),
+                 "%s%s",
+                 app->prompt_label,
+                 app->prompt_input);
+        draw_text(&app->font, text_x, text_y, line);
+
+        if (app->prompt_completion_active && app->prompt_completion_count > 0) {
+            char hint[128];
+            snprintf(hint,
+                     sizeof(hint),
+                     "  [%zu/%zu]",
+                     app->prompt_completion_index + 1,
+                     app->prompt_completion_count);
+
+            glColor3f(app->ed->theme.completion_fg.r,
+                      app->ed->theme.completion_fg.g,
+                      app->ed->theme.completion_fg.b);
+            draw_text(&app->font,
+                      text_x + text_width(&app->font, line),
+                      text_y,
+                      hint);
+
+            if (app->prompt_completion_preview_count > 0) {
+                float row_h = app->font.line_height;
+                float popup_pad = m.pad_y;
+                float popup_h = row_h * (float)app->prompt_completion_preview_count + popup_pad * 2.0f;
+                float popup_y = y - popup_h;
+
+                glDisable(GL_TEXTURE_2D);
+                glColor3f(app->ed->theme.minibuffer_bg.r,
+                          app->ed->theme.minibuffer_bg.g,
+                          app->ed->theme.minibuffer_bg.b);
+                draw_rect(0.0f, popup_y, (float)app->width, popup_h);
+
+                for (size_t i = 0; i < app->prompt_completion_preview_count; i++) {
+                    size_t absolute = app->prompt_completion_preview_start + i;
+                    char row[1100];
+                    snprintf(row,
+                             sizeof(row),
+                             "%c %s",
+                             absolute == app->prompt_completion_index ? '>' : ' ',
+                             app->prompt_completion_preview[i]);
+
+                    if (absolute == app->prompt_completion_index) {
+                        glColor3f(app->ed->theme.minibuffer_fg.r,
+                                  app->ed->theme.minibuffer_fg.g,
+                                  app->ed->theme.minibuffer_fg.b);
+                    } else {
+                        glColor3f(app->ed->theme.completion_fg.r,
+                                  app->ed->theme.completion_fg.g,
+                                  app->ed->theme.completion_fg.b);
+                    }
+
+                    draw_text(&app->font,
+                              text_x,
+                              line_baseline(app, popup_y + popup_pad + row_h * (float)i),
+                              row);
+                }
+            }
+        }
+    } else if (app->mode == APP_MODE_PREFIX) {
+        char line[ECEX_PREFIX_SIZE + 8];
+        snprintf(line, sizeof(line), "%s-", app->prefix);
+        draw_text(&app->font, text_x, text_y, line);
+    } else {
+        draw_text(&app->font, text_x, text_y, app->message);
+    }
+}
+
+static int should_highlight_interactive_line(buffer_t *buf, size_t zero_based_line) {
+    if (!buf || !buffer_is_interactive(buf)) return 0;
+
+    size_t current_line = buffer_current_line_number(buf);
+    if (current_line > 0) current_line--;
+
+    return current_line == zero_based_line;
+}
+
+static void set_editor_text_color(app_t *app, int highlighted) {
+    if (highlighted) {
+        glColor3f(app->ed->theme.interactive_highlight_fg.r,
+                  app->ed->theme.interactive_highlight_fg.g,
+                  app->ed->theme.interactive_highlight_fg.b);
+    } else {
+        glColor3f(app->ed->theme.fg.r,
+                  app->ed->theme.fg.g,
+                  app->ed->theme.fg.b);
+    }
+}
+
+static float text_width_range(app_t *app, buffer_t *buf, size_t start, size_t end) {
+    char *text = buffer_substring(buf, start, end);
+    if (!text) return 0.0f;
+
+    float width = text_width(&app->font, text);
+    free(text);
+    return width;
+}
+
+static void draw_selection_for_line(app_t *app,
+                                    buffer_t *buf,
+                                    view_rect_t rect,
+                                    size_t visible_start,
+                                    size_t line_end,
+                                    float line_top) {
+    if (!buffer_has_selection(buf)) return;
+
+    size_t sel_start = 0;
+    size_t sel_end = 0;
+    buffer_selection_range(buf, &sel_start, &sel_end);
+
+    if (sel_end <= visible_start || sel_start > line_end) return;
+
+    size_t draw_start = ECEX_MAX(sel_start, visible_start);
+    size_t draw_end = ECEX_MIN(sel_end, line_end);
+
+    float x = rect.x + ui_metrics(app).content_x + gutter_width(app, buf) + text_width_range(app, buf, visible_start, draw_start);
+    float w = text_width_range(app, buf, draw_start, draw_end);
+
+    /* If the selection contains only this line's newline, show a visible sliver
+     * at end-of-line instead of making the active region appear to vanish. */
+    if (w < 1.0f && sel_end > line_end && draw_start == line_end) {
+        w = mono_cell_width(app) * 0.5f;
+    }
+
+    if (w < 1.0f) return;
+
+    glDisable(GL_TEXTURE_2D);
+    glColor3f(app->ed->theme.region_bg.r,
+              app->ed->theme.region_bg.g,
+              app->ed->theme.region_bg.b);
+    draw_rect(x, line_top, w, app->font.line_height);
+}
+
+static void draw_buffer_line(app_t *app,
+                             buffer_t *buf,
+                             view_rect_t rect,
+                             size_t zero_based_line,
+                             size_t line_start,
+                             size_t line_end,
+                             float line_top) {
+    if (line_start > line_end) return;
+
+    ui_metrics_t m = ui_metrics(app);
+    int highlighted = should_highlight_interactive_line(buf, zero_based_line);
+    size_t current_zero = buffer_current_line_number(buf);
+    if (current_zero > 0) current_zero--;
+
+    if (app->ed->theme.current_line_enabled && current_zero == zero_based_line) {
+        glDisable(GL_TEXTURE_2D);
+        glColor3f(app->ed->theme.current_line_bg.r,
+                  app->ed->theme.current_line_bg.g,
+                  app->ed->theme.current_line_bg.b);
+        draw_rect(rect.x, line_top, rect.w, app->font.line_height);
+    }
+
+    if (highlighted) {
+        glDisable(GL_TEXTURE_2D);
+        glColor3f(app->ed->theme.interactive_highlight_bg.r,
+                  app->ed->theme.interactive_highlight_bg.g,
+                  app->ed->theme.interactive_highlight_bg.b);
+        draw_rect(rect.x,
+                  line_top,
+                  rect.w,
+                  app->font.line_height);
+    }
+
+    size_t line_len = line_end - line_start;
+    size_t col = ECEX_MIN(buf->scroll_col, line_len);
+    size_t start = line_start + col;
+
+    draw_selection_for_line(app, buf, rect, start, line_end, line_top);
+
+    float gutter = gutter_width(app, buf);
+    if (gutter > 0.0f) {
+        char nbuf[32];
+        snprintf(nbuf, sizeof(nbuf), "%zu", zero_based_line + 1);
+        glColor3f(app->ed->theme.completion_fg.r,
+                  app->ed->theme.completion_fg.g,
+                  app->ed->theme.completion_fg.b);
+        draw_text(&app->font, rect.x + m.pad_x * 0.5f, line_baseline(app, line_top), nbuf);
+    }
+
+    char *line = buffer_substring(buf, start, line_end);
+    if (!line) return;
+
+    set_editor_text_color(app, highlighted);
+    draw_text(&app->font, rect.x + m.content_x + gutter, line_baseline(app, line_top), line);
+    free(line);
+}
+
+static void render_cursor(app_t *app, buffer_t *buf, view_rect_t rect) {
+    ui_metrics_t m = ui_metrics(app);
+
+    size_t cursor_line = buffer_current_line_number(buf);
+    if (cursor_line > 0) cursor_line--;
+
+    if (cursor_line < buf->scroll_line) return;
+
+    size_t visible_row = cursor_line - buf->scroll_line;
+    if (visible_row >= visible_row_count_for_rect(app, rect)) return;
+
+    size_t line_start = buffer_current_line_start(buf);
+    size_t cursor_col = buffer_current_column(buf);
+
+    size_t visible_start = line_start + ECEX_MIN(buf->scroll_col, cursor_col);
+    char *prefix = buffer_substring(buf, visible_start, buf->point);
+    float x = rect.x + m.content_x + gutter_width(app, buf) + (prefix ? text_width(&app->font, prefix) : 0.0f);
+    float line_top = rect.y + m.content_top + (float)visible_row * app->font.line_height;
+    float cursor_top = line_top + (app->font.line_height - m.cursor_h) * 0.5f;
+
+    free(prefix);
+
+    glDisable(GL_TEXTURE_2D);
+    glColor3f(app->ed->theme.cursor.r,
+              app->ed->theme.cursor.g,
+              app->ed->theme.cursor.b);
+    draw_rect(x, cursor_top, m.cursor_w, m.cursor_h);
+}
+
+static void draw_window_border(app_t *app, view_rect_t rect, int active) {
+    glDisable(GL_TEXTURE_2D);
+
+    if (active) {
+        glColor3f(app->ed->theme.cursor.r,
+                  app->ed->theme.cursor.g,
+                  app->ed->theme.cursor.b);
+    } else {
+        glColor3f(app->ed->theme.status_border.r,
+                  app->ed->theme.status_border.g,
+                  app->ed->theme.status_border.b);
+    }
+
+    draw_rect(rect.x, rect.y, rect.w, 1.0f);
+    draw_rect(rect.x, rect.y + rect.h - 1.0f, rect.w, 1.0f);
+    draw_rect(rect.x, rect.y, 1.0f, rect.h);
+    draw_rect(rect.x + rect.w - 1.0f, rect.y, 1.0f, rect.h);
+}
+
+static void render_buffer_window(app_t *app, ecex_window_t *win, size_t index, float editor_h) {
+    if (!app || !win || !win->buffer) return;
+
+    view_rect_t rect;
+    rect.x = win->x * (float)app->width;
+    rect.y = win->y * editor_h;
+    rect.w = win->w * (float)app->width;
+    rect.h = win->h * editor_h;
+
+    if (rect.w < 2.0f || rect.h < 2.0f) return;
+
+    buffer_t *buf = win->buffer;
+    ui_metrics_t m = ui_metrics(app);
+
+    int sx = (int)rect.x;
+    int sy = app->height - (int)(rect.y + rect.h);
+    int sw = (int)rect.w;
+    int sh = (int)rect.h;
+    if (sw < 1 || sh < 1) return;
+
+    glEnable(GL_SCISSOR_TEST);
+    glScissor(sx, sy, sw, sh);
+
+    if (index == app->ed->current_window_index) {
+        ensure_cursor_visible(app, buf, rect);
+    }
+
+    size_t rows = visible_row_count_for_rect(app, rect);
+    size_t pos = offset_for_line(buf, buf->scroll_line);
+    float line_top = rect.y + m.content_top;
+
+    for (size_t row = 0; row < rows; row++) {
+        size_t line_start = pos;
+        size_t line_end = buffer_line_end_at(buf, line_start);
+
+        draw_buffer_line(app,
+                         buf,
+                         rect,
+                         buf->scroll_line + row,
+                         line_start,
+                         line_end,
+                         line_top);
+
+        if (line_end >= buf->len) break;
+        pos = line_end + 1;
+        line_top += app->font.line_height;
+    }
+
+    if (index == app->ed->current_window_index) {
+        render_cursor(app, buf, rect);
+    }
+
+    glDisable(GL_SCISSOR_TEST);
+    draw_window_border(app, rect, index == app->ed->current_window_index);
+}
+
+static void render_windows(app_t *app) {
+    ui_metrics_t m = ui_metrics(app);
+    float editor_h = (float)app->height - m.status_h;
+    if (minibuffer_visible(app)) editor_h -= m.minibuffer_h;
+    if (editor_h < 1.0f) editor_h = 1.0f;
+
+    if (app->ed->window_count == 0) return;
+
+    for (size_t i = 0; i < app->ed->window_count; i++) {
+        render_buffer_window(app, &app->ed->windows[i], i, editor_h);
+    }
+}
+
+void render(app_t *app) {
+    if (!app || !app->window || !app->ed) return;
+
+    glfwGetFramebufferSize(app->window, &app->width, &app->height);
+
+    setup_2d(app->width, app->height);
+
+    glClearColor(app->ed->theme.bg.r,
+                 app->ed->theme.bg.g,
+                 app->ed->theme.bg.b,
+                 1.0f);
+    glClear(GL_COLOR_BUFFER_BIT);
+
+    glEnable(GL_BLEND);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+    render_windows(app);
+    render_minibuffer(app);
+    render_status_bar(app);
+}
diff --git a/src/util.c b/src/util.c
new file mode 100644
index 0000000..feb3c0e
--- /dev/null
+++ b/src/util.c
@@ -0,0 +1,71 @@
+#include "util.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int ecex_file_exists(const char *path) {
+    if (!path || !path[0]) return 0;
+
+    FILE *file = fopen(path, "rb");
+    if (!file) return 0;
+
+    fclose(file);
+    return 1;
+}
+
+char *ecex_read_entire_file(const char *path, size_t *out_size) {
+    FILE *file = fopen(path, "rb");
+    if (!file) return NULL;
+
+    if (fseek(file, 0, SEEK_END) != 0) {
+        fclose(file);
+        return NULL;
+    }
+
+    long size = ftell(file);
+    if (size < 0) {
+        fclose(file);
+        return NULL;
+    }
+
+    rewind(file);
+
+    char *data = malloc((size_t)size + 1);
+    if (!data) {
+        fclose(file);
+        return NULL;
+    }
+
+    size_t read_count = fread(data, 1, (size_t)size, file);
+    fclose(file);
+
+    if (read_count != (size_t)size) {
+        free(data);
+        return NULL;
+    }
+
+    data[size] = '\0';
+
+    if (out_size) {
+        *out_size = (size_t)size;
+    }
+
+    return data;
+}
+
+
+char *ecex_strdup(const char *s) {
+    if (!s) return NULL;
+
+    size_t len = 0;
+    while (s[len]) len++;
+
+    char *out = malloc(len + 1);
+    if (!out) return NULL;
+
+    for (size_t i = 0; i <= len; i++) {
+        out[i] = s[i];
+    }
+
+    return out;
+}