1// ImGui Renderer for: OpenGL3 (modern OpenGL with shaders / programmatic pipeline) 2// This needs to be used along with a Platform Binding (e.g. GLFW, SDL, Win32, custom..) 3// (Note: We are using GL3W as a helper library to access OpenGL functions since there is no standard header to access modern OpenGL functions easily. Alternatives are GLEW, Glad, etc..) 4 5// Implemented features: 6// [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID in imgui.cpp. 7 8// You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this. 9// If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp. 10// https://github.com/ocornut/imgui 11 12// CHANGELOG 13// (minor and older changes stripped away, please see git history for details) 14// 2018-07-10: OpenGL: Support for more GLSL versions (based on the GLSL version string). Added error output when shaders fail to compile/link. 15// 2018-06-08: Misc: Extracted imgui_impl_opengl3.cpp/.h away from the old combined GLFW/SDL+OpenGL3 examples. 16// 2018-06-08: OpenGL: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle. 17// 2018-05-25: OpenGL: Removed unnecessary backup/restore of GL_ELEMENT_ARRAY_BUFFER_BINDING since this is part of the VAO state. 18// 2018-05-14: OpenGL: Making the call to glBindSampler() optional so 3.2 context won't fail if the function is a NULL pointer. 19// 2018-03-06: OpenGL: Added const char* glsl_version parameter to ImGui_ImplOpenGL3_Init() so user can override the GLSL version e.g. "#version 150". 20// 2018-02-23: OpenGL: Create the VAO in the render function so the setup can more easily be used with multiple shared GL context. 21// 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplSdlGL3_RenderDrawData() in the .h file so you can call it yourself. 22// 2018-01-07: OpenGL: Changed GLSL shader version from 330 to 150. 23// 2017-09-01: OpenGL: Save and restore current bound sampler. Save and restore current polygon mode. 24// 2017-05-01: OpenGL: Fixed save and restore of current blend func state. 25// 2017-05-01: OpenGL: Fixed save and restore of current GL_ACTIVE_TEXTURE. 26// 2016-09-05: OpenGL: Fixed save and restore of current scissor rectangle. 27// 2016-07-29: OpenGL: Explicitly setting GL_UNPACK_ROW_LENGTH to reduce issues because SDL changes it. (#752) 28 29//---------------------------------------- 30// OpenGL GLSL GLSL 31// version version string 32//---------------------------------------- 33// 2.0 110 "#version 110" 34// 2.1 120 35// 3.0 130 36// 3.1 140 37// 3.2 150 "#version 150" 38// 3.3 330 39// 4.0 400 40// 4.1 410 41// 4.2 420 42// 4.3 430 43// ES 2.0 100 "#version 100" 44// ES 3.0 300 "#version 300 es" 45//---------------------------------------- 46 47#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS) 48#define _CRT_SECURE_NO_WARNINGS 49#endif 50 51#include "imgui/imgui.h" 52#include "imgui_impl_opengl3.h" 53#include <stdio.h> 54#if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier 55#include <stddef.h> // intptr_t 56#else 57#include <stdint.h> // intptr_t 58#endif 59 60#include <epoxy/gl.h> 61//#include "gl3w.h" // This example is using gl3w to access OpenGL functions. You may use another OpenGL loader/header such as: glew, glext, glad, glLoadGen, etc. 62//#include <glew.h> 63//#include <glext.h> 64//#include <glad/glad.h> 65 66// OpenGL Data 67static char g_GlslVersionString[32] = ""; 68static GLuint g_FontTexture = 0; 69static GLuint g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0; 70static int g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0; 71static int g_AttribLocationPosition = 0, g_AttribLocationUV = 0, g_AttribLocationColor = 0; 72static unsigned int g_VboHandle = 0, g_ElementsHandle = 0; 73 74// Functions 75bool ImGui_ImplOpenGL3_Init(const char* glsl_version) 76{ 77 // Store GLSL version string so we can refer to it later in case we recreate shaders. Note: GLSL version is NOT the same as GL version. Leave this to NULL if unsure. 78 if (glsl_version == NULL) 79 glsl_version = "#version 130"; 80 IM_ASSERT((int)strlen(glsl_version) + 2 < IM_ARRAYSIZE(g_GlslVersionString)); 81 strcpy(g_GlslVersionString, glsl_version); 82 strcat(g_GlslVersionString, "\n"); 83 return true; 84} 85 86void ImGui_ImplOpenGL3_Shutdown() 87{ 88 ImGui_ImplOpenGL3_DestroyDeviceObjects(); 89} 90 91void ImGui_ImplOpenGL3_NewFrame() 92{ 93 if (!g_FontTexture) 94 ImGui_ImplOpenGL3_CreateDeviceObjects(); 95} 96 97// OpenGL3 Render function. 98// (this used to be set in io.RenderDrawListsFn and called by ImGui::Render(), but you can now call this directly from your main loop) 99// Note that this implementation is little overcomplicated because we are saving/setting up/restoring every OpenGL state explicitly, in order to be able to run within any OpenGL engine that doesn't do so. 100void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data) 101{ 102 // Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates) 103 ImGuiIO& io = ImGui::GetIO(); 104 int fb_width = (int)(draw_data->DisplaySize.x * io.DisplayFramebufferScale.x); 105 int fb_height = (int)(draw_data->DisplaySize.y * io.DisplayFramebufferScale.y); 106 if (fb_width <= 0 || fb_height <= 0) 107 return; 108 draw_data->ScaleClipRects(io.DisplayFramebufferScale); 109 110 // Backup GL state 111 GLenum last_active_texture; glGetIntegerv(GL_ACTIVE_TEXTURE, (GLint*)&last_active_texture); 112 glActiveTexture(GL_TEXTURE0); 113 GLint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, &last_program); 114 GLint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); 115 GLint last_sampler; glGetIntegerv(GL_SAMPLER_BINDING, &last_sampler); 116 GLint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer); 117 GLint last_vertex_array; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array); 118 GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode); 119 GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport); 120 GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box); 121 GLenum last_blend_src_rgb; glGetIntegerv(GL_BLEND_SRC_RGB, (GLint*)&last_blend_src_rgb); 122 GLenum last_blend_dst_rgb; glGetIntegerv(GL_BLEND_DST_RGB, (GLint*)&last_blend_dst_rgb); 123 GLenum last_blend_src_alpha; glGetIntegerv(GL_BLEND_SRC_ALPHA, (GLint*)&last_blend_src_alpha); 124 GLenum last_blend_dst_alpha; glGetIntegerv(GL_BLEND_DST_ALPHA, (GLint*)&last_blend_dst_alpha); 125 GLenum last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, (GLint*)&last_blend_equation_rgb); 126 GLenum last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, (GLint*)&last_blend_equation_alpha); 127 GLboolean last_enable_blend = glIsEnabled(GL_BLEND); 128 GLboolean last_enable_cull_face = glIsEnabled(GL_CULL_FACE); 129 GLboolean last_enable_depth_test = glIsEnabled(GL_DEPTH_TEST); 130 GLboolean last_enable_scissor_test = glIsEnabled(GL_SCISSOR_TEST); 131 132 // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill 133 glEnable(GL_BLEND); 134 glBlendEquation(GL_FUNC_ADD); 135 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); 136 glDisable(GL_CULL_FACE); 137 glDisable(GL_DEPTH_TEST); 138 glEnable(GL_SCISSOR_TEST); 139 glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); 140 141 // Setup viewport, orthographic projection matrix 142 // Our visible imgui space lies from draw_data->DisplayPps (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayMin is typically (0,0) for single viewport apps. 143 glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height); 144 float L = draw_data->DisplayPos.x; 145 float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x; 146 float T = draw_data->DisplayPos.y; 147 float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y; 148 const float ortho_projection[4][4] = 149 { 150 { 2.0f/(R-L), 0.0f, 0.0f, 0.0f }, 151 { 0.0f, 2.0f/(T-B), 0.0f, 0.0f }, 152 { 0.0f, 0.0f, -1.0f, 0.0f }, 153 { (R+L)/(L-R), (T+B)/(B-T), 0.0f, 1.0f }, 154 }; 155 glUseProgram(g_ShaderHandle); 156 glUniform1i(g_AttribLocationTex, 0); 157 glUniformMatrix4fv(g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]); 158 if (glBindSampler) glBindSampler(0, 0); // We use combined texture/sampler state. Applications using GL 3.3 may set that otherwise. 159 160 // Recreate the VAO every time 161 // (This is to easily allow multiple GL contexts. VAO are not shared among GL contexts, and we don't track creation/deletion of windows so we don't have an obvious key to use to cache them.) 162 GLuint vao_handle = 0; 163 glGenVertexArrays(1, &vao_handle); 164 glBindVertexArray(vao_handle); 165 glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle); 166 glEnableVertexAttribArray(g_AttribLocationPosition); 167 glEnableVertexAttribArray(g_AttribLocationUV); 168 glEnableVertexAttribArray(g_AttribLocationColor); 169 glVertexAttribPointer(g_AttribLocationPosition, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, pos)); 170 glVertexAttribPointer(g_AttribLocationUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, uv)); 171 glVertexAttribPointer(g_AttribLocationColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, col)); 172 173 // Draw 174 ImVec2 pos = draw_data->DisplayPos; 175 for (int n = 0; n < draw_data->CmdListsCount; n++) 176 { 177 const ImDrawList* cmd_list = draw_data->CmdLists[n]; 178 const ImDrawIdx* idx_buffer_offset = 0; 179 180 glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle); 181 glBufferData(GL_ARRAY_BUFFER, (GLsizeiptr)cmd_list->VtxBuffer.Size * sizeof(ImDrawVert), (const GLvoid*)cmd_list->VtxBuffer.Data, GL_STREAM_DRAW); 182 183 glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ElementsHandle); 184 glBufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx), (const GLvoid*)cmd_list->IdxBuffer.Data, GL_STREAM_DRAW); 185 186 for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++) 187 { 188 const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i]; 189 if (pcmd->UserCallback) 190 { 191 // User callback (registered via ImDrawList::AddCallback) 192 pcmd->UserCallback(cmd_list, pcmd); 193 } 194 else 195 { 196 ImVec4 clip_rect = ImVec4(pcmd->ClipRect.x - pos.x, pcmd->ClipRect.y - pos.y, pcmd->ClipRect.z - pos.x, pcmd->ClipRect.w - pos.y); 197 if (clip_rect.x < fb_width && clip_rect.y < fb_height && clip_rect.z >= 0.0f && clip_rect.w >= 0.0f) 198 { 199 // Apply scissor/clipping rectangle 200 glScissor((int)clip_rect.x, (int)(fb_height - clip_rect.w), (int)(clip_rect.z - clip_rect.x), (int)(clip_rect.w - clip_rect.y)); 201 202 // Bind texture, Draw 203 glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->TextureId); 204 glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer_offset); 205 } 206 } 207 idx_buffer_offset += pcmd->ElemCount; 208 } 209 } 210 glDeleteVertexArrays(1, &vao_handle); 211 212 // Restore modified GL state 213 glUseProgram(last_program); 214 glBindTexture(GL_TEXTURE_2D, last_texture); 215 if (glBindSampler) glBindSampler(0, last_sampler); 216 glActiveTexture(last_active_texture); 217 glBindVertexArray(last_vertex_array); 218 glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer); 219 glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha); 220 glBlendFuncSeparate(last_blend_src_rgb, last_blend_dst_rgb, last_blend_src_alpha, last_blend_dst_alpha); 221 if (last_enable_blend) glEnable(GL_BLEND); else glDisable(GL_BLEND); 222 if (last_enable_cull_face) glEnable(GL_CULL_FACE); else glDisable(GL_CULL_FACE); 223 if (last_enable_depth_test) glEnable(GL_DEPTH_TEST); else glDisable(GL_DEPTH_TEST); 224 if (last_enable_scissor_test) glEnable(GL_SCISSOR_TEST); else glDisable(GL_SCISSOR_TEST); 225 glPolygonMode(GL_FRONT_AND_BACK, (GLenum)last_polygon_mode[0]); 226 glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]); 227 glScissor(last_scissor_box[0], last_scissor_box[1], (GLsizei)last_scissor_box[2], (GLsizei)last_scissor_box[3]); 228} 229 230bool ImGui_ImplOpenGL3_CreateFontsTexture() 231{ 232 // Build texture atlas 233 ImGuiIO& io = ImGui::GetIO(); 234 unsigned char* pixels; 235 int width, height; 236 io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height); // Load as RGBA 32-bits (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory. 237 238 // Upload texture to graphics system 239 GLint last_texture; 240 glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); 241 glGenTextures(1, &g_FontTexture); 242 glBindTexture(GL_TEXTURE_2D, g_FontTexture); 243 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); 244 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); 245 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0); 246 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels); 247 248 // Store our identifier 249 io.Fonts->TexID = (void *)(intptr_t)g_FontTexture; 250 251 // Restore state 252 glBindTexture(GL_TEXTURE_2D, last_texture); 253 254 return true; 255} 256 257void ImGui_ImplOpenGL3_DestroyFontsTexture() 258{ 259 if (g_FontTexture) 260 { 261 ImGuiIO& io = ImGui::GetIO(); 262 glDeleteTextures(1, &g_FontTexture); 263 io.Fonts->TexID = 0; 264 g_FontTexture = 0; 265 } 266} 267 268// If you get an error please report on github. You may try different GL context version or GLSL version. 269static bool CheckShader(GLuint handle, const char* desc) 270{ 271 GLint status = 0, log_length = 0; 272 glGetShaderiv(handle, GL_COMPILE_STATUS, &status); 273 glGetShaderiv(handle, GL_INFO_LOG_LENGTH, &log_length); 274 if (status == GL_FALSE) 275 fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to compile %s!\n", desc); 276 if (log_length > 0) 277 { 278 ImVector<char> buf; 279 buf.resize((int)(log_length + 1)); 280 glGetShaderInfoLog(handle, log_length, NULL, (GLchar*)buf.begin()); 281 fprintf(stderr, "%s\n", buf.begin()); 282 } 283 return status == GL_TRUE; 284} 285 286// If you get an error please report on github. You may try different GL context version or GLSL version. 287static bool CheckProgram(GLuint handle, const char* desc) 288{ 289 GLint status = 0, log_length = 0; 290 glGetProgramiv(handle, GL_LINK_STATUS, &status); 291 glGetProgramiv(handle, GL_INFO_LOG_LENGTH, &log_length); 292 if (status == GL_FALSE) 293 fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to link %s!\n", desc); 294 if (log_length > 0) 295 { 296 ImVector<char> buf; 297 buf.resize((int)(log_length + 1)); 298 glGetProgramInfoLog(handle, log_length, NULL, (GLchar*)buf.begin()); 299 fprintf(stderr, "%s\n", buf.begin()); 300 } 301 return status == GL_TRUE; 302} 303 304bool ImGui_ImplOpenGL3_CreateDeviceObjects() 305{ 306 // Backup GL state 307 GLint last_texture, last_array_buffer, last_vertex_array; 308 glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); 309 glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer); 310 glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array); 311 312 // Parse GLSL version string 313 int glsl_version = 130; 314 sscanf(g_GlslVersionString, "#version %d", &glsl_version); 315 316 const GLchar* vertex_shader_glsl_120 = 317 "uniform mat4 ProjMtx;\n" 318 "attribute vec2 Position;\n" 319 "attribute vec2 UV;\n" 320 "attribute vec4 Color;\n" 321 "varying vec2 Frag_UV;\n" 322 "varying vec4 Frag_Color;\n" 323 "void main()\n" 324 "{\n" 325 " Frag_UV = UV;\n" 326 " Frag_Color = Color;\n" 327 " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" 328 "}\n"; 329 330 const GLchar* vertex_shader_glsl_130 = 331 "uniform mat4 ProjMtx;\n" 332 "in vec2 Position;\n" 333 "in vec2 UV;\n" 334 "in vec4 Color;\n" 335 "out vec2 Frag_UV;\n" 336 "out vec4 Frag_Color;\n" 337 "void main()\n" 338 "{\n" 339 " Frag_UV = UV;\n" 340 " Frag_Color = Color;\n" 341 " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" 342 "}\n"; 343 344 const GLchar* fragment_shader_glsl_120 = 345 "#ifdef GL_ES\n" 346 " precision mediump float;\n" 347 "#endif\n" 348 "uniform sampler2D Texture;\n" 349 "varying vec2 Frag_UV;\n" 350 "varying vec4 Frag_Color;\n" 351 "void main()\n" 352 "{\n" 353 " gl_FragColor = Frag_Color * texture2D(Texture, Frag_UV.st);\n" 354 "}\n"; 355 356 const GLchar* fragment_shader_glsl_130 = 357 "uniform sampler2D Texture;\n" 358 "in vec2 Frag_UV;\n" 359 "in vec4 Frag_Color;\n" 360 "out vec4 Out_Color;\n" 361 "void main()\n" 362 "{\n" 363 " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n" 364 "}\n"; 365 366 // Select shaders matching our GLSL versions 367 const GLchar* vertex_shader = NULL; 368 const GLchar* fragment_shader = NULL; 369 if (glsl_version < 130) 370 { 371 vertex_shader = vertex_shader_glsl_120; 372 fragment_shader = fragment_shader_glsl_120; 373 } 374 else 375 { 376 vertex_shader = vertex_shader_glsl_130; 377 fragment_shader = fragment_shader_glsl_130; 378 } 379 380 // Create shaders 381 const GLchar* vertex_shader_with_version[2] = { g_GlslVersionString, vertex_shader }; 382 g_VertHandle = glCreateShader(GL_VERTEX_SHADER); 383 glShaderSource(g_VertHandle, 2, vertex_shader_with_version, NULL); 384 glCompileShader(g_VertHandle); 385 CheckShader(g_VertHandle, "vertex shader"); 386 387 const GLchar* fragment_shader_with_version[2] = { g_GlslVersionString, fragment_shader }; 388 g_FragHandle = glCreateShader(GL_FRAGMENT_SHADER); 389 glShaderSource(g_FragHandle, 2, fragment_shader_with_version, NULL); 390 glCompileShader(g_FragHandle); 391 CheckShader(g_FragHandle, "fragment shader"); 392 393 g_ShaderHandle = glCreateProgram(); 394 glAttachShader(g_ShaderHandle, g_VertHandle); 395 glAttachShader(g_ShaderHandle, g_FragHandle); 396 glLinkProgram(g_ShaderHandle); 397 CheckProgram(g_ShaderHandle, "shader program"); 398 399 g_AttribLocationTex = glGetUniformLocation(g_ShaderHandle, "Texture"); 400 g_AttribLocationProjMtx = glGetUniformLocation(g_ShaderHandle, "ProjMtx"); 401 g_AttribLocationPosition = glGetAttribLocation(g_ShaderHandle, "Position"); 402 g_AttribLocationUV = glGetAttribLocation(g_ShaderHandle, "UV"); 403 g_AttribLocationColor = glGetAttribLocation(g_ShaderHandle, "Color"); 404 405 // Create buffers 406 glGenBuffers(1, &g_VboHandle); 407 glGenBuffers(1, &g_ElementsHandle); 408 409 ImGui_ImplOpenGL3_CreateFontsTexture(); 410 411 // Restore modified GL state 412 glBindTexture(GL_TEXTURE_2D, last_texture); 413 glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer); 414 glBindVertexArray(last_vertex_array); 415 416 return true; 417} 418 419void ImGui_ImplOpenGL3_DestroyDeviceObjects() 420{ 421 if (g_VboHandle) glDeleteBuffers(1, &g_VboHandle); 422 if (g_ElementsHandle) glDeleteBuffers(1, &g_ElementsHandle); 423 g_VboHandle = g_ElementsHandle = 0; 424 425 if (g_ShaderHandle && g_VertHandle) glDetachShader(g_ShaderHandle, g_VertHandle); 426 if (g_VertHandle) glDeleteShader(g_VertHandle); 427 g_VertHandle = 0; 428 429 if (g_ShaderHandle && g_FragHandle) glDetachShader(g_ShaderHandle, g_FragHandle); 430 if (g_FragHandle) glDeleteShader(g_FragHandle); 431 g_FragHandle = 0; 432 433 if (g_ShaderHandle) glDeleteProgram(g_ShaderHandle); 434 g_ShaderHandle = 0; 435 436 ImGui_ImplOpenGL3_DestroyFontsTexture(); 437} 438