deps/nuklear_glfw_gl2.h - third_party/glfw - Git at Google

 /*
  * Nuklear - v1.32.0 - public domain
  * no warrenty implied; use at your own risk.
  * authored from 2015-2017 by Micha Mettke
  */
 /*
  * ==============================================================
  *
  *                              API
  *
  * ===============================================================
  */
 #ifndef NK_GLFW_GL2_H_
 #define NK_GLFW_GL2_H_

 #include <GLFW/glfw3.h>

 enum nk_glfw_init_state{
     NK_GLFW3_DEFAULT = 0,
     NK_GLFW3_INSTALL_CALLBACKS
 };
 NK_API struct nk_context*   nk_glfw3_init(GLFWwindow *win, enum nk_glfw_init_state);
 NK_API void                 nk_glfw3_font_stash_begin(struct nk_font_atlas **atlas);
 NK_API void                 nk_glfw3_font_stash_end(void);

 NK_API void                 nk_glfw3_new_frame(void);
 NK_API void                 nk_glfw3_render(enum nk_anti_aliasing);
 NK_API void                 nk_glfw3_shutdown(void);

 NK_API void                 nk_glfw3_char_callback(GLFWwindow *win, unsigned int codepoint);
 NK_API void                 nk_gflw3_scroll_callback(GLFWwindow *win, double xoff, double yoff);

 #endif

 /*
  * ==============================================================
  *
  *                          IMPLEMENTATION
  *
  * ===============================================================
  */
 #ifdef NK_GLFW_GL2_IMPLEMENTATION

 #ifndef NK_GLFW_TEXT_MAX
 #define NK_GLFW_TEXT_MAX 256
 #endif
 #ifndef NK_GLFW_DOUBLE_CLICK_LO
 #define NK_GLFW_DOUBLE_CLICK_LO 0.02
 #endif
 #ifndef NK_GLFW_DOUBLE_CLICK_HI
 #define NK_GLFW_DOUBLE_CLICK_HI 0.2
 #endif

 struct nk_glfw_device {
     struct nk_buffer cmds;
     struct nk_draw_null_texture null;
     GLuint font_tex;
 };

 struct nk_glfw_vertex {
     float position[2];
     float uv[2];
     nk_byte col[4];
 };

 static struct nk_glfw {
     GLFWwindow *win;
     int width, height;
     int display_width, display_height;
     struct nk_glfw_device ogl;
     struct nk_context ctx;
     struct nk_font_atlas atlas;
     struct nk_vec2 fb_scale;
     unsigned int text[NK_GLFW_TEXT_MAX];
     int text_len;
     struct nk_vec2 scroll;
     double last_button_click;
 } glfw;

 NK_INTERN void
 nk_glfw3_device_upload_atlas(const void *image, int width, int height)
 {
     struct nk_glfw_device *dev = &glfw.ogl;
     glGenTextures(1, &dev->font_tex);
     glBindTexture(GL_TEXTURE_2D, dev->font_tex);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
     glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, (GLsizei)width, (GLsizei)height, 0,
                 GL_RGBA, GL_UNSIGNED_BYTE, image);
 }

 NK_API void
 nk_glfw3_render(enum nk_anti_aliasing AA)
 {
     /* setup global state */
     struct nk_glfw_device *dev = &glfw.ogl;
     glPushAttrib(GL_ENABLE_BIT|GL_COLOR_BUFFER_BIT|GL_TRANSFORM_BIT);
     glDisable(GL_CULL_FACE);
     glDisable(GL_DEPTH_TEST);
     glEnable(GL_SCISSOR_TEST);
     glEnable(GL_BLEND);
     glEnable(GL_TEXTURE_2D);
     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

     /* setup viewport/project */
     glViewport(0,0,(GLsizei)glfw.display_width,(GLsizei)glfw.display_height);
     glMatrixMode(GL_PROJECTION);
     glPushMatrix();
     glLoadIdentity();
     glOrtho(0.0f, glfw.width, glfw.height, 0.0f, -1.0f, 1.0f);
     glMatrixMode(GL_MODELVIEW);
     glPushMatrix();
     glLoadIdentity();

     glEnableClientState(GL_VERTEX_ARRAY);
     glEnableClientState(GL_TEXTURE_COORD_ARRAY);
     glEnableClientState(GL_COLOR_ARRAY);
     {
         GLsizei vs = sizeof(struct nk_glfw_vertex);
         size_t vp = offsetof(struct nk_glfw_vertex, position);
         size_t vt = offsetof(struct nk_glfw_vertex, uv);
         size_t vc = offsetof(struct nk_glfw_vertex, col);

         /* convert from command queue into draw list and draw to screen */
         const struct nk_draw_command *cmd;
         const nk_draw_index *offset = NULL;
         struct nk_buffer vbuf, ebuf;

         /* fill convert configuration */
         struct nk_convert_config config;
         static const struct nk_draw_vertex_layout_element vertex_layout[] = {
             {NK_VERTEX_POSITION, NK_FORMAT_FLOAT, NK_OFFSETOF(struct nk_glfw_vertex, position)},
             {NK_VERTEX_TEXCOORD, NK_FORMAT_FLOAT, NK_OFFSETOF(struct nk_glfw_vertex, uv)},
             {NK_VERTEX_COLOR, NK_FORMAT_R8G8B8A8, NK_OFFSETOF(struct nk_glfw_vertex, col)},
             {NK_VERTEX_LAYOUT_END}
         };
         NK_MEMSET(&config, 0, sizeof(config));
         config.vertex_layout = vertex_layout;
         config.vertex_size = sizeof(struct nk_glfw_vertex);
         config.vertex_alignment = NK_ALIGNOF(struct nk_glfw_vertex);
         config.null = dev->null;
         config.circle_segment_count = 22;
         config.curve_segment_count = 22;
         config.arc_segment_count = 22;
         config.global_alpha = 1.0f;
         config.shape_AA = AA;
         config.line_AA = AA;

         /* convert shapes into vertexes */
         nk_buffer_init_default(&vbuf);
         nk_buffer_init_default(&ebuf);
         nk_convert(&glfw.ctx, &dev->cmds, &vbuf, &ebuf, &config);

         /* setup vertex buffer pointer */
         {const void *vertices = nk_buffer_memory_const(&vbuf);
         glVertexPointer(2, GL_FLOAT, vs, (const void*)((const nk_byte*)vertices + vp));
         glTexCoordPointer(2, GL_FLOAT, vs, (const void*)((const nk_byte*)vertices + vt));
         glColorPointer(4, GL_UNSIGNED_BYTE, vs, (const void*)((const nk_byte*)vertices + vc));}

         /* iterate over and execute each draw command */
         offset = (const nk_draw_index*)nk_buffer_memory_const(&ebuf);
         nk_draw_foreach(cmd, &glfw.ctx, &dev->cmds)
         {
             if (!cmd->elem_count) continue;
             glBindTexture(GL_TEXTURE_2D, (GLuint)cmd->texture.id);
             glScissor(
                 (GLint)(cmd->clip_rect.x * glfw.fb_scale.x),
                 (GLint)((glfw.height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * glfw.fb_scale.y),
                 (GLint)(cmd->clip_rect.w * glfw.fb_scale.x),
                 (GLint)(cmd->clip_rect.h * glfw.fb_scale.y));
             glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_SHORT, offset);
             offset += cmd->elem_count;
         }
         nk_clear(&glfw.ctx);
         nk_buffer_free(&vbuf);
         nk_buffer_free(&ebuf);
     }

     /* default OpenGL state */
     glDisableClientState(GL_VERTEX_ARRAY);
     glDisableClientState(GL_TEXTURE_COORD_ARRAY);
     glDisableClientState(GL_COLOR_ARRAY);

     glDisable(GL_CULL_FACE);
     glDisable(GL_DEPTH_TEST);
     glDisable(GL_SCISSOR_TEST);
     glDisable(GL_BLEND);
     glDisable(GL_TEXTURE_2D);

     glBindTexture(GL_TEXTURE_2D, 0);
     glMatrixMode(GL_MODELVIEW);
     glPopMatrix();
     glMatrixMode(GL_PROJECTION);
     glPopMatrix();
     glPopAttrib();
 }

 NK_API void
 nk_glfw3_char_callback(GLFWwindow *win, unsigned int codepoint)
 {
     (void)win;
     if (glfw.text_len < NK_GLFW_TEXT_MAX)
         glfw.text[glfw.text_len++] = codepoint;
 }

 NK_API void
 nk_gflw3_scroll_callback(GLFWwindow *win, double xoff, double yoff)
 {
     (void)win; (void)xoff;
     glfw.scroll.x += (float)xoff;
     glfw.scroll.y += (float)yoff;
 }

 NK_API void
 nk_glfw3_mouse_button_callback(GLFWwindow* window, int button, int action, int mods)
 {
     double x, y;
     if (button != GLFW_MOUSE_BUTTON_LEFT) return;
     glfwGetCursorPos(window, &x, &y);
     if (action == GLFW_PRESS)  {
         double dt = glfwGetTime() - glfw.last_button_click;
         if (dt > NK_GLFW_DOUBLE_CLICK_LO && dt < NK_GLFW_DOUBLE_CLICK_HI)
             nk_input_button(&glfw.ctx, NK_BUTTON_DOUBLE, (int)x, (int)y, nk_true);
         glfw.last_button_click = glfwGetTime();
     } else nk_input_button(&glfw.ctx, NK_BUTTON_DOUBLE, (int)x, (int)y, nk_false);
 }

 NK_INTERN void
 nk_glfw3_clipbard_paste(nk_handle usr, struct nk_text_edit *edit)
 {
     const char *text = glfwGetClipboardString(glfw.win);
     if (text) nk_textedit_paste(edit, text, nk_strlen(text));
     (void)usr;
 }

 NK_INTERN void
 nk_glfw3_clipbard_copy(nk_handle usr, const char *text, int len)
 {
     char *str = 0;
     (void)usr;
     if (!len) return;
     str = (char*)malloc((size_t)len+1);
     if (!str) return;
     NK_MEMCPY(str, text, (size_t)len);
     str[len] = '\0';
     glfwSetClipboardString(glfw.win, str);
     free(str);
 }

 NK_API struct nk_context*
 nk_glfw3_init(GLFWwindow *win, enum nk_glfw_init_state init_state)
 {
     glfw.win = win;
     if (init_state == NK_GLFW3_INSTALL_CALLBACKS) {
         glfwSetScrollCallback(win, nk_gflw3_scroll_callback);
         glfwSetCharCallback(win, nk_glfw3_char_callback);
         glfwSetMouseButtonCallback(win, nk_glfw3_mouse_button_callback);
     }
     nk_init_default(&glfw.ctx, 0);
     glfw.ctx.clip.copy = nk_glfw3_clipbard_copy;
     glfw.ctx.clip.paste = nk_glfw3_clipbard_paste;
     glfw.ctx.clip.userdata = nk_handle_ptr(0);
     nk_buffer_init_default(&glfw.ogl.cmds);
     return &glfw.ctx;
 }

 NK_API void
 nk_glfw3_font_stash_begin(struct nk_font_atlas **atlas)
 {
     nk_font_atlas_init_default(&glfw.atlas);
     nk_font_atlas_begin(&glfw.atlas);
     *atlas = &glfw.atlas;
 }

 NK_API void
 nk_glfw3_font_stash_end(void)
 {
     const void *image; int w, h;
     image = nk_font_atlas_bake(&glfw.atlas, &w, &h, NK_FONT_ATLAS_RGBA32);
     nk_glfw3_device_upload_atlas(image, w, h);
     nk_font_atlas_end(&glfw.atlas, nk_handle_id((int)glfw.ogl.font_tex), &glfw.ogl.null);
     if (glfw.atlas.default_font)
         nk_style_set_font(&glfw.ctx, &glfw.atlas.default_font->handle);
 }

 NK_API void
 nk_glfw3_new_frame(void)
 {
     int i;
     double x, y;
     struct nk_context *ctx = &glfw.ctx;
     struct GLFWwindow *win = glfw.win;

     glfwGetWindowSize(win, &glfw.width, &glfw.height);
     glfwGetFramebufferSize(win, &glfw.display_width, &glfw.display_height);
     glfw.fb_scale.x = (float)glfw.display_width/(float)glfw.width;
     glfw.fb_scale.y = (float)glfw.display_height/(float)glfw.height;

     nk_input_begin(ctx);
     for (i = 0; i < glfw.text_len; ++i)
         nk_input_unicode(ctx, glfw.text[i]);

     /* optional grabbing behavior */
     if (ctx->input.mouse.grab)
         glfwSetInputMode(glfw.win, GLFW_CURSOR, GLFW_CURSOR_HIDDEN);
     else if (ctx->input.mouse.ungrab)
         glfwSetInputMode(glfw.win, GLFW_CURSOR, GLFW_CURSOR_NORMAL);

     nk_input_key(ctx, NK_KEY_DEL, glfwGetKey(win, GLFW_KEY_DELETE) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_ENTER, glfwGetKey(win, GLFW_KEY_ENTER) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_TAB, glfwGetKey(win, GLFW_KEY_TAB) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_BACKSPACE, glfwGetKey(win, GLFW_KEY_BACKSPACE) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_UP, glfwGetKey(win, GLFW_KEY_UP) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_DOWN, glfwGetKey(win, GLFW_KEY_DOWN) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_TEXT_START, glfwGetKey(win, GLFW_KEY_HOME) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_TEXT_END, glfwGetKey(win, GLFW_KEY_END) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_SCROLL_START, glfwGetKey(win, GLFW_KEY_HOME) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_SCROLL_END, glfwGetKey(win, GLFW_KEY_END) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_SCROLL_DOWN, glfwGetKey(win, GLFW_KEY_PAGE_DOWN) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_SCROLL_UP, glfwGetKey(win, GLFW_KEY_PAGE_UP) == GLFW_PRESS);
     nk_input_key(ctx, NK_KEY_SHIFT, glfwGetKey(win, GLFW_KEY_LEFT_SHIFT) == GLFW_PRESS||
                                     glfwGetKey(win, GLFW_KEY_RIGHT_SHIFT) == GLFW_PRESS);

     if (glfwGetKey(win, GLFW_KEY_LEFT_CONTROL) == GLFW_PRESS ||
         glfwGetKey(win, GLFW_KEY_RIGHT_CONTROL) == GLFW_PRESS) {
         nk_input_key(ctx, NK_KEY_COPY, glfwGetKey(win, GLFW_KEY_C) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_PASTE, glfwGetKey(win, GLFW_KEY_V) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_CUT, glfwGetKey(win, GLFW_KEY_X) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_TEXT_UNDO, glfwGetKey(win, GLFW_KEY_Z) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_TEXT_REDO, glfwGetKey(win, GLFW_KEY_R) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_TEXT_WORD_LEFT, glfwGetKey(win, GLFW_KEY_LEFT) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_TEXT_WORD_RIGHT, glfwGetKey(win, GLFW_KEY_RIGHT) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_TEXT_LINE_START, glfwGetKey(win, GLFW_KEY_B) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_TEXT_LINE_END, glfwGetKey(win, GLFW_KEY_E) == GLFW_PRESS);
     } else {
         nk_input_key(ctx, NK_KEY_LEFT, glfwGetKey(win, GLFW_KEY_LEFT) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_RIGHT, glfwGetKey(win, GLFW_KEY_RIGHT) == GLFW_PRESS);
         nk_input_key(ctx, NK_KEY_COPY, 0);
         nk_input_key(ctx, NK_KEY_PASTE, 0);
         nk_input_key(ctx, NK_KEY_CUT, 0);
         nk_input_key(ctx, NK_KEY_SHIFT, 0);
     }

     glfwGetCursorPos(win, &x, &y);
     nk_input_motion(ctx, (int)x, (int)y);
     if (ctx->input.mouse.grabbed) {
         glfwSetCursorPos(glfw.win, ctx->input.mouse.prev.x, ctx->input.mouse.prev.y);
         ctx->input.mouse.pos.x = ctx->input.mouse.prev.x;
         ctx->input.mouse.pos.y = ctx->input.mouse.prev.y;
     }

     nk_input_button(ctx, NK_BUTTON_LEFT, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_LEFT) == GLFW_PRESS);
     nk_input_button(ctx, NK_BUTTON_MIDDLE, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_MIDDLE) == GLFW_PRESS);
     nk_input_button(ctx, NK_BUTTON_RIGHT, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_RIGHT) == GLFW_PRESS);
     nk_input_scroll(ctx, glfw.scroll);
     nk_input_end(&glfw.ctx);
     glfw.text_len = 0;
     glfw.scroll = nk_vec2(0,0);
 }

 NK_API
 void nk_glfw3_shutdown(void)
 {
     struct nk_glfw_device *dev = &glfw.ogl;
     nk_font_atlas_clear(&glfw.atlas);
     nk_free(&glfw.ctx);
     glDeleteTextures(1, &dev->font_tex);
     nk_buffer_free(&dev->cmds);
     NK_MEMSET(&glfw, 0, sizeof(glfw));
 }

 #endif
	/*
	* Nuklear - v1.32.0 - public domain
	* no warrenty implied; use at your own risk.
	* authored from 2015-2017 by Micha Mettke
	*/
	/*
	* ==============================================================
	*
	* API
	*
	* ===============================================================
	*/
	#ifndef NK_GLFW_GL2_H_
	#define NK_GLFW_GL2_H_

	#include <GLFW/glfw3.h>

	enum nk_glfw_init_state{
	NK_GLFW3_DEFAULT = 0,
	NK_GLFW3_INSTALL_CALLBACKS
	};
	NK_API struct nk_context* nk_glfw3_init(GLFWwindow *win, enum nk_glfw_init_state);
	NK_API void nk_glfw3_font_stash_begin(struct nk_font_atlas **atlas);
	NK_API void nk_glfw3_font_stash_end(void);

	NK_API void nk_glfw3_new_frame(void);
	NK_API void nk_glfw3_render(enum nk_anti_aliasing);
	NK_API void nk_glfw3_shutdown(void);

	NK_API void nk_glfw3_char_callback(GLFWwindow *win, unsigned int codepoint);
	NK_API void nk_gflw3_scroll_callback(GLFWwindow *win, double xoff, double yoff);

	#endif

	/*
	* ==============================================================
	*
	* IMPLEMENTATION
	*
	* ===============================================================
	*/
	#ifdef NK_GLFW_GL2_IMPLEMENTATION

	#ifndef NK_GLFW_TEXT_MAX
	#define NK_GLFW_TEXT_MAX 256
	#endif
	#ifndef NK_GLFW_DOUBLE_CLICK_LO
	#define NK_GLFW_DOUBLE_CLICK_LO 0.02
	#endif
	#ifndef NK_GLFW_DOUBLE_CLICK_HI
	#define NK_GLFW_DOUBLE_CLICK_HI 0.2
	#endif

	struct nk_glfw_device {
	struct nk_buffer cmds;
	struct nk_draw_null_texture null;
	GLuint font_tex;
	};

	struct nk_glfw_vertex {
	float position[2];
	float uv[2];
	nk_byte col[4];
	};

	static struct nk_glfw {
	GLFWwindow *win;
	int width, height;
	int display_width, display_height;
	struct nk_glfw_device ogl;
	struct nk_context ctx;
	struct nk_font_atlas atlas;
	struct nk_vec2 fb_scale;
	unsigned int text[NK_GLFW_TEXT_MAX];
	int text_len;
	struct nk_vec2 scroll;
	double last_button_click;
	} glfw;

	NK_INTERN void
	nk_glfw3_device_upload_atlas(const void *image, int width, int height)
	{
	struct nk_glfw_device *dev = &glfw.ogl;
	glGenTextures(1, &dev->font_tex);
	glBindTexture(GL_TEXTURE_2D, dev->font_tex);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, (GLsizei)width, (GLsizei)height, 0,
	GL_RGBA, GL_UNSIGNED_BYTE, image);
	}

	NK_API void
	nk_glfw3_render(enum nk_anti_aliasing AA)
	{
	/* setup global state */
	struct nk_glfw_device *dev = &glfw.ogl;
	glPushAttrib(GL_ENABLE_BIT\|GL_COLOR_BUFFER_BIT\|GL_TRANSFORM_BIT);
	glDisable(GL_CULL_FACE);
	glDisable(GL_DEPTH_TEST);
	glEnable(GL_SCISSOR_TEST);
	glEnable(GL_BLEND);
	glEnable(GL_TEXTURE_2D);
	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

	/* setup viewport/project */
	glViewport(0,0,(GLsizei)glfw.display_width,(GLsizei)glfw.display_height);
	glMatrixMode(GL_PROJECTION);
	glPushMatrix();
	glLoadIdentity();
	glOrtho(0.0f, glfw.width, glfw.height, 0.0f, -1.0f, 1.0f);
	glMatrixMode(GL_MODELVIEW);
	glPushMatrix();
	glLoadIdentity();

	glEnableClientState(GL_VERTEX_ARRAY);
	glEnableClientState(GL_TEXTURE_COORD_ARRAY);
	glEnableClientState(GL_COLOR_ARRAY);
	{
	GLsizei vs = sizeof(struct nk_glfw_vertex);
	size_t vp = offsetof(struct nk_glfw_vertex, position);
	size_t vt = offsetof(struct nk_glfw_vertex, uv);
	size_t vc = offsetof(struct nk_glfw_vertex, col);

	/* convert from command queue into draw list and draw to screen */
	const struct nk_draw_command *cmd;
	const nk_draw_index *offset = NULL;
	struct nk_buffer vbuf, ebuf;

	/* fill convert configuration */
	struct nk_convert_config config;
	static const struct nk_draw_vertex_layout_element vertex_layout[] = {
	{NK_VERTEX_POSITION, NK_FORMAT_FLOAT, NK_OFFSETOF(struct nk_glfw_vertex, position)},
	{NK_VERTEX_TEXCOORD, NK_FORMAT_FLOAT, NK_OFFSETOF(struct nk_glfw_vertex, uv)},
	{NK_VERTEX_COLOR, NK_FORMAT_R8G8B8A8, NK_OFFSETOF(struct nk_glfw_vertex, col)},
	{NK_VERTEX_LAYOUT_END}
	};
	NK_MEMSET(&config, 0, sizeof(config));
	config.vertex_layout = vertex_layout;
	config.vertex_size = sizeof(struct nk_glfw_vertex);
	config.vertex_alignment = NK_ALIGNOF(struct nk_glfw_vertex);
	config.null = dev->null;
	config.circle_segment_count = 22;
	config.curve_segment_count = 22;
	config.arc_segment_count = 22;
	config.global_alpha = 1.0f;
	config.shape_AA = AA;
	config.line_AA = AA;

	/* convert shapes into vertexes */
	nk_buffer_init_default(&vbuf);
	nk_buffer_init_default(&ebuf);
	nk_convert(&glfw.ctx, &dev->cmds, &vbuf, &ebuf, &config);

	/* setup vertex buffer pointer */
	{const void *vertices = nk_buffer_memory_const(&vbuf);
	glVertexPointer(2, GL_FLOAT, vs, (const void)((const nk_byte)vertices + vp));
	glTexCoordPointer(2, GL_FLOAT, vs, (const void)((const nk_byte)vertices + vt));
	glColorPointer(4, GL_UNSIGNED_BYTE, vs, (const void)((const nk_byte)vertices + vc));}

	/* iterate over and execute each draw command */
	offset = (const nk_draw_index*)nk_buffer_memory_const(&ebuf);
	nk_draw_foreach(cmd, &glfw.ctx, &dev->cmds)
	{
	if (!cmd->elem_count) continue;
	glBindTexture(GL_TEXTURE_2D, (GLuint)cmd->texture.id);
	glScissor(
	(GLint)(cmd->clip_rect.x * glfw.fb_scale.x),
	(GLint)((glfw.height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * glfw.fb_scale.y),
	(GLint)(cmd->clip_rect.w * glfw.fb_scale.x),
	(GLint)(cmd->clip_rect.h * glfw.fb_scale.y));
	glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_SHORT, offset);
	offset += cmd->elem_count;
	}
	nk_clear(&glfw.ctx);
	nk_buffer_free(&vbuf);
	nk_buffer_free(&ebuf);
	}

	/* default OpenGL state */
	glDisableClientState(GL_VERTEX_ARRAY);
	glDisableClientState(GL_TEXTURE_COORD_ARRAY);
	glDisableClientState(GL_COLOR_ARRAY);

	glDisable(GL_CULL_FACE);
	glDisable(GL_DEPTH_TEST);
	glDisable(GL_SCISSOR_TEST);
	glDisable(GL_BLEND);
	glDisable(GL_TEXTURE_2D);

	glBindTexture(GL_TEXTURE_2D, 0);
	glMatrixMode(GL_MODELVIEW);
	glPopMatrix();
	glMatrixMode(GL_PROJECTION);
	glPopMatrix();
	glPopAttrib();
	}

	NK_API void
	nk_glfw3_char_callback(GLFWwindow *win, unsigned int codepoint)
	{
	(void)win;
	if (glfw.text_len < NK_GLFW_TEXT_MAX)
	glfw.text[glfw.text_len++] = codepoint;
	}

	NK_API void
	nk_gflw3_scroll_callback(GLFWwindow *win, double xoff, double yoff)
	{
	(void)win; (void)xoff;
	glfw.scroll.x += (float)xoff;
	glfw.scroll.y += (float)yoff;
	}

	NK_API void
	nk_glfw3_mouse_button_callback(GLFWwindow* window, int button, int action, int mods)
	{
	double x, y;
	if (button != GLFW_MOUSE_BUTTON_LEFT) return;
	glfwGetCursorPos(window, &x, &y);
	if (action == GLFW_PRESS) {
	double dt = glfwGetTime() - glfw.last_button_click;
	if (dt > NK_GLFW_DOUBLE_CLICK_LO && dt < NK_GLFW_DOUBLE_CLICK_HI)
	nk_input_button(&glfw.ctx, NK_BUTTON_DOUBLE, (int)x, (int)y, nk_true);
	glfw.last_button_click = glfwGetTime();
	} else nk_input_button(&glfw.ctx, NK_BUTTON_DOUBLE, (int)x, (int)y, nk_false);
	}

	NK_INTERN void
	nk_glfw3_clipbard_paste(nk_handle usr, struct nk_text_edit *edit)
	{
	const char *text = glfwGetClipboardString(glfw.win);
	if (text) nk_textedit_paste(edit, text, nk_strlen(text));
	(void)usr;
	}

	NK_INTERN void
	nk_glfw3_clipbard_copy(nk_handle usr, const char *text, int len)
	{
	char *str = 0;
	(void)usr;
	if (!len) return;
	str = (char*)malloc((size_t)len+1);
	if (!str) return;
	NK_MEMCPY(str, text, (size_t)len);
	str[len] = '\0';
	glfwSetClipboardString(glfw.win, str);
	free(str);
	}

	NK_API struct nk_context*
	nk_glfw3_init(GLFWwindow *win, enum nk_glfw_init_state init_state)
	{
	glfw.win = win;
	if (init_state == NK_GLFW3_INSTALL_CALLBACKS) {
	glfwSetScrollCallback(win, nk_gflw3_scroll_callback);
	glfwSetCharCallback(win, nk_glfw3_char_callback);
	glfwSetMouseButtonCallback(win, nk_glfw3_mouse_button_callback);
	}
	nk_init_default(&glfw.ctx, 0);
	glfw.ctx.clip.copy = nk_glfw3_clipbard_copy;
	glfw.ctx.clip.paste = nk_glfw3_clipbard_paste;
	glfw.ctx.clip.userdata = nk_handle_ptr(0);
	nk_buffer_init_default(&glfw.ogl.cmds);
	return &glfw.ctx;
	}

	NK_API void
	nk_glfw3_font_stash_begin(struct nk_font_atlas **atlas)
	{
	nk_font_atlas_init_default(&glfw.atlas);
	nk_font_atlas_begin(&glfw.atlas);
	*atlas = &glfw.atlas;
	}

	NK_API void
	nk_glfw3_font_stash_end(void)
	{
	const void *image; int w, h;
	image = nk_font_atlas_bake(&glfw.atlas, &w, &h, NK_FONT_ATLAS_RGBA32);
	nk_glfw3_device_upload_atlas(image, w, h);
	nk_font_atlas_end(&glfw.atlas, nk_handle_id((int)glfw.ogl.font_tex), &glfw.ogl.null);
	if (glfw.atlas.default_font)
	nk_style_set_font(&glfw.ctx, &glfw.atlas.default_font->handle);
	}

	NK_API void
	nk_glfw3_new_frame(void)
	{
	int i;
	double x, y;
	struct nk_context *ctx = &glfw.ctx;
	struct GLFWwindow *win = glfw.win;

	glfwGetWindowSize(win, &glfw.width, &glfw.height);
	glfwGetFramebufferSize(win, &glfw.display_width, &glfw.display_height);
	glfw.fb_scale.x = (float)glfw.display_width/(float)glfw.width;
	glfw.fb_scale.y = (float)glfw.display_height/(float)glfw.height;

	nk_input_begin(ctx);
	for (i = 0; i < glfw.text_len; ++i)
	nk_input_unicode(ctx, glfw.text[i]);

	/* optional grabbing behavior */
	if (ctx->input.mouse.grab)
	glfwSetInputMode(glfw.win, GLFW_CURSOR, GLFW_CURSOR_HIDDEN);
	else if (ctx->input.mouse.ungrab)
	glfwSetInputMode(glfw.win, GLFW_CURSOR, GLFW_CURSOR_NORMAL);

	nk_input_key(ctx, NK_KEY_DEL, glfwGetKey(win, GLFW_KEY_DELETE) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_ENTER, glfwGetKey(win, GLFW_KEY_ENTER) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TAB, glfwGetKey(win, GLFW_KEY_TAB) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_BACKSPACE, glfwGetKey(win, GLFW_KEY_BACKSPACE) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_UP, glfwGetKey(win, GLFW_KEY_UP) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_DOWN, glfwGetKey(win, GLFW_KEY_DOWN) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TEXT_START, glfwGetKey(win, GLFW_KEY_HOME) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TEXT_END, glfwGetKey(win, GLFW_KEY_END) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_SCROLL_START, glfwGetKey(win, GLFW_KEY_HOME) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_SCROLL_END, glfwGetKey(win, GLFW_KEY_END) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_SCROLL_DOWN, glfwGetKey(win, GLFW_KEY_PAGE_DOWN) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_SCROLL_UP, glfwGetKey(win, GLFW_KEY_PAGE_UP) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_SHIFT, glfwGetKey(win, GLFW_KEY_LEFT_SHIFT) == GLFW_PRESS\|\|
	glfwGetKey(win, GLFW_KEY_RIGHT_SHIFT) == GLFW_PRESS);

	if (glfwGetKey(win, GLFW_KEY_LEFT_CONTROL) == GLFW_PRESS \|\|
	glfwGetKey(win, GLFW_KEY_RIGHT_CONTROL) == GLFW_PRESS) {
	nk_input_key(ctx, NK_KEY_COPY, glfwGetKey(win, GLFW_KEY_C) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_PASTE, glfwGetKey(win, GLFW_KEY_V) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_CUT, glfwGetKey(win, GLFW_KEY_X) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TEXT_UNDO, glfwGetKey(win, GLFW_KEY_Z) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TEXT_REDO, glfwGetKey(win, GLFW_KEY_R) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TEXT_WORD_LEFT, glfwGetKey(win, GLFW_KEY_LEFT) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TEXT_WORD_RIGHT, glfwGetKey(win, GLFW_KEY_RIGHT) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TEXT_LINE_START, glfwGetKey(win, GLFW_KEY_B) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_TEXT_LINE_END, glfwGetKey(win, GLFW_KEY_E) == GLFW_PRESS);
	} else {
	nk_input_key(ctx, NK_KEY_LEFT, glfwGetKey(win, GLFW_KEY_LEFT) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_RIGHT, glfwGetKey(win, GLFW_KEY_RIGHT) == GLFW_PRESS);
	nk_input_key(ctx, NK_KEY_COPY, 0);
	nk_input_key(ctx, NK_KEY_PASTE, 0);
	nk_input_key(ctx, NK_KEY_CUT, 0);
	nk_input_key(ctx, NK_KEY_SHIFT, 0);
	}

	glfwGetCursorPos(win, &x, &y);
	nk_input_motion(ctx, (int)x, (int)y);
	if (ctx->input.mouse.grabbed) {
	glfwSetCursorPos(glfw.win, ctx->input.mouse.prev.x, ctx->input.mouse.prev.y);
	ctx->input.mouse.pos.x = ctx->input.mouse.prev.x;
	ctx->input.mouse.pos.y = ctx->input.mouse.prev.y;
	}

	nk_input_button(ctx, NK_BUTTON_LEFT, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_LEFT) == GLFW_PRESS);
	nk_input_button(ctx, NK_BUTTON_MIDDLE, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_MIDDLE) == GLFW_PRESS);
	nk_input_button(ctx, NK_BUTTON_RIGHT, (int)x, (int)y, glfwGetMouseButton(win, GLFW_MOUSE_BUTTON_RIGHT) == GLFW_PRESS);
	nk_input_scroll(ctx, glfw.scroll);
	nk_input_end(&glfw.ctx);
	glfw.text_len = 0;
	glfw.scroll = nk_vec2(0,0);
	}

	NK_API
	void nk_glfw3_shutdown(void)
	{
	struct nk_glfw_device *dev = &glfw.ogl;
	nk_font_atlas_clear(&glfw.atlas);
	nk_free(&glfw.ctx);
	glDeleteTextures(1, &dev->font_tex);
	nk_buffer_free(&dev->cmds);
	NK_MEMSET(&glfw, 0, sizeof(glfw));
	}

	#endif