| // dear imgui: Renderer for modern OpenGL with shaders / programmatic pipeline |
| // - Desktop GL: 3.x 4.x |
| // - Embedded GL: ES 2.0 (WebGL 1.0), ES 3.0 (WebGL 2.0) |
| // This needs to be used along with a Platform Binding (e.g. GLFW, SDL, Win32, custom..) |
| |
| // Implemented features: |
| // [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID in imgui.cpp. |
| // [x] Renderer: Desktop GL only: Support for large meshes (64k+ vertices) with 16-bits indices. |
| |
| // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this. |
| // If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp. |
| // https://github.com/ocornut/imgui |
| |
| // CHANGELOG |
| // (minor and older changes stripped away, please see git history for details) |
| // 2019-05-29: OpenGL: Desktop GL only: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag. |
| // 2019-04-30: OpenGL: Added support for special ImDrawCallback_ResetRenderState callback to reset render state. |
| // 2019-03-29: OpenGL: Not calling glBindBuffer more than necessary in the render loop. |
| // 2019-03-15: OpenGL: Added a dummy GL call + comments in ImGui_ImplOpenGL3_Init() to detect uninitialized GL function loaders early. |
| // 2019-03-03: OpenGL: Fix support for ES 2.0 (WebGL 1.0). |
| // 2019-02-20: OpenGL: Fix for OSX not supporting OpenGL 4.5, we don't try to read GL_CLIP_ORIGIN even if defined by the headers/loader. |
| // 2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display. |
| // 2019-02-01: OpenGL: Using GLSL 410 shaders for any version over 410 (e.g. 430, 450). |
| // 2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window. |
| // 2018-11-13: OpenGL: Support for GL 4.5's glClipControl(GL_UPPER_LEFT) / GL_CLIP_ORIGIN. |
| // 2018-08-29: OpenGL: Added support for more OpenGL loaders: glew and glad, with comments indicative that any loader can be used. |
| // 2018-08-09: OpenGL: Default to OpenGL ES 3 on iOS and Android. GLSL version default to "#version 300 ES". |
| // 2018-07-30: OpenGL: Support for GLSL 300 ES and 410 core. Fixes for Emscripten compilation. |
| // 2018-07-10: OpenGL: Support for more GLSL versions (based on the GLSL version string). Added error output when shaders fail to compile/link. |
| // 2018-06-08: Misc: Extracted imgui_impl_opengl3.cpp/.h away from the old combined GLFW/SDL+OpenGL3 examples. |
| // 2018-06-08: OpenGL: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle. |
| // 2018-05-25: OpenGL: Removed unnecessary backup/restore of GL_ELEMENT_ARRAY_BUFFER_BINDING since this is part of the VAO state. |
| // 2018-05-14: OpenGL: Making the call to glBindSampler() optional so 3.2 context won't fail if the function is a NULL pointer. |
| // 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". |
| // 2018-02-23: OpenGL: Create the VAO in the render function so the setup can more easily be used with multiple shared GL context. |
| // 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplSdlGL3_RenderDrawData() in the .h file so you can call it yourself. |
| // 2018-01-07: OpenGL: Changed GLSL shader version from 330 to 150. |
| // 2017-09-01: OpenGL: Save and restore current bound sampler. Save and restore current polygon mode. |
| // 2017-05-01: OpenGL: Fixed save and restore of current blend func state. |
| // 2017-05-01: OpenGL: Fixed save and restore of current GL_ACTIVE_TEXTURE. |
| // 2016-09-05: OpenGL: Fixed save and restore of current scissor rectangle. |
| // 2016-07-29: OpenGL: Explicitly setting GL_UNPACK_ROW_LENGTH to reduce issues because SDL changes it. (#752) |
| |
| //---------------------------------------- |
| // OpenGL GLSL GLSL |
| // version version string |
| //---------------------------------------- |
| // 2.0 110 "#version 110" |
| // 2.1 120 "#version 120" |
| // 3.0 130 "#version 130" |
| // 3.1 140 "#version 140" |
| // 3.2 150 "#version 150" |
| // 3.3 330 "#version 330 core" |
| // 4.0 400 "#version 400 core" |
| // 4.1 410 "#version 410 core" |
| // 4.2 420 "#version 410 core" |
| // 4.3 430 "#version 430 core" |
| // ES 2.0 100 "#version 100" = WebGL 1.0 |
| // ES 3.0 300 "#version 300 es" = WebGL 2.0 |
| //---------------------------------------- |
| |
| #if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS) |
| #define _CRT_SECURE_NO_WARNINGS |
| #endif |
| |
| #include "imgui.h" |
| #include "imgui_impl_opengl3.h" |
| #include <stdio.h> |
| #if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier |
| #include <stddef.h> // intptr_t |
| #else |
| #include <stdint.h> // intptr_t |
| #endif |
| #if defined(__APPLE__) |
| #include "TargetConditionals.h" |
| #endif |
| |
| // Auto-detect GL version |
| #if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) |
| #if (defined(__APPLE__) && TARGET_OS_IOS) || (defined(__ANDROID__)) |
| #define IMGUI_IMPL_OPENGL_ES3 // iOS, Android -> GL ES 3, "#version 300 es" |
| #elif defined(__EMSCRIPTEN__) |
| #define IMGUI_IMPL_OPENGL_ES2 // Emscripten -> GL ES 2, "#version 100" |
| #endif |
| #endif |
| |
| #if defined(IMGUI_IMPL_OPENGL_ES2) |
| #include <GLES2/gl2.h> |
| #elif defined(IMGUI_IMPL_OPENGL_ES3) |
| #include <GLES3/gl3.h> // Use GL ES 3 |
| #else |
| // About Desktop OpenGL function loaders: |
| // Modern desktop OpenGL doesn't have a standard portable header file to load OpenGL function pointers. |
| // Helper libraries are often used for this purpose! Here we are supporting a few common ones (gl3w, glew, glad). |
| // You may use another loader/header of your choice (glext, glLoadGen, etc.), or chose to manually implement your own. |
| #if defined(IMGUI_IMPL_OPENGL_LOADER_GL3W) |
| #include <GL/gl3w.h> // Needs to be initialized with gl3wInit() in user's code |
| #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLEW) |
| #include <GL/glew.h> // Needs to be initialized with glewInit() in user's code |
| #elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD) |
| #include <glad/glad.h> // Needs to be initialized with gladLoadGL() in user's code |
| #else |
| #include IMGUI_IMPL_OPENGL_LOADER_CUSTOM |
| #endif |
| #endif |
| |
| // Desktop GL has glDrawElementsBaseVertex() which GL ES and WebGL don't have. |
| #if defined(IMGUI_IMPL_OPENGL_ES2) || defined(IMGUI_IMPL_OPENGL_ES3) |
| #define IMGUI_IMPL_OPENGL_HAS_DRAW_WITH_BASE_VERTEX 0 |
| #else |
| #define IMGUI_IMPL_OPENGL_HAS_DRAW_WITH_BASE_VERTEX 1 |
| #endif |
| |
| // OpenGL Data |
| static char g_GlslVersionString[32] = ""; |
| static GLuint g_FontTexture = 0; |
| static GLuint g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0; |
| static int g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0; // Uniforms location |
| static int g_AttribLocationVtxPos = 0, g_AttribLocationVtxUV = 0, g_AttribLocationVtxColor = 0; // Vertex attributes location |
| static unsigned int g_VboHandle = 0, g_ElementsHandle = 0; |
| |
| // Functions |
| bool ImGui_ImplOpenGL3_Init(const char* glsl_version) |
| { |
| // Setup back-end capabilities flags |
| ImGuiIO& io = ImGui::GetIO(); |
| io.BackendRendererName = "imgui_impl_opengl3"; |
| #if IMGUI_IMPL_OPENGL_HAS_DRAW_WITH_BASE_VERTEX |
| io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes. |
| #endif |
| |
| // 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. |
| #if defined(IMGUI_IMPL_OPENGL_ES2) |
| if (glsl_version == NULL) |
| glsl_version = "#version 100"; |
| #elif defined(IMGUI_IMPL_OPENGL_ES3) |
| if (glsl_version == NULL) |
| glsl_version = "#version 300 es"; |
| #else |
| if (glsl_version == NULL) |
| glsl_version = "#version 130"; |
| #endif |
| IM_ASSERT((int)strlen(glsl_version) + 2 < IM_ARRAYSIZE(g_GlslVersionString)); |
| strcpy(g_GlslVersionString, glsl_version); |
| strcat(g_GlslVersionString, "\n"); |
| |
| // Make a dummy GL call (we don't actually need the result) |
| // IF YOU GET A CRASH HERE: it probably means that you haven't initialized the OpenGL function loader used by this code. |
| // Desktop OpenGL 3/4 need a function loader. See the IMGUI_IMPL_OPENGL_LOADER_xxx explanation above. |
| GLint current_texture; |
| glGetIntegerv(GL_TEXTURE_BINDING_2D, ¤t_texture); |
| |
| return true; |
| } |
| |
| void ImGui_ImplOpenGL3_Shutdown() |
| { |
| ImGui_ImplOpenGL3_DestroyDeviceObjects(); |
| } |
| |
| void ImGui_ImplOpenGL3_NewFrame() |
| { |
| if (!g_FontTexture) |
| ImGui_ImplOpenGL3_CreateDeviceObjects(); |
| } |
| |
| static void ImGui_ImplOpenGL3_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height, GLuint vertex_array_object) |
| { |
| // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill |
| glEnable(GL_BLEND); |
| glBlendEquation(GL_FUNC_ADD); |
| glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); |
| glDisable(GL_CULL_FACE); |
| glDisable(GL_DEPTH_TEST); |
| glEnable(GL_SCISSOR_TEST); |
| #ifdef GL_POLYGON_MODE |
| glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); |
| #endif |
| |
| // Setup viewport, orthographic projection matrix |
| // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps. |
| glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height); |
| float L = draw_data->DisplayPos.x; |
| float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x; |
| float T = draw_data->DisplayPos.y; |
| float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y; |
| const float ortho_projection[4][4] = |
| { |
| { 2.0f/(R-L), 0.0f, 0.0f, 0.0f }, |
| { 0.0f, 2.0f/(T-B), 0.0f, 0.0f }, |
| { 0.0f, 0.0f, -1.0f, 0.0f }, |
| { (R+L)/(L-R), (T+B)/(B-T), 0.0f, 1.0f }, |
| }; |
| glUseProgram(g_ShaderHandle); |
| glUniform1i(g_AttribLocationTex, 0); |
| glUniformMatrix4fv(g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]); |
| #ifdef GL_SAMPLER_BINDING |
| glBindSampler(0, 0); // We use combined texture/sampler state. Applications using GL 3.3 may set that otherwise. |
| #endif |
| |
| (void)vertex_array_object; |
| #ifndef IMGUI_IMPL_OPENGL_ES2 |
| glBindVertexArray(vertex_array_object); |
| #endif |
| |
| // Bind vertex/index buffers and setup attributes for ImDrawVert |
| glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle); |
| glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ElementsHandle); |
| glEnableVertexAttribArray(g_AttribLocationVtxPos); |
| glEnableVertexAttribArray(g_AttribLocationVtxUV); |
| glEnableVertexAttribArray(g_AttribLocationVtxColor); |
| glVertexAttribPointer(g_AttribLocationVtxPos, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, pos)); |
| glVertexAttribPointer(g_AttribLocationVtxUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, uv)); |
| glVertexAttribPointer(g_AttribLocationVtxColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, col)); |
| } |
| |
| // OpenGL3 Render function. |
| // (this used to be set in io.RenderDrawListsFn and called by ImGui::Render(), but you can now call this directly from your main loop) |
| // 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. |
| void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data) |
| { |
| // Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates) |
| int fb_width = (int)(draw_data->DisplaySize.x * draw_data->FramebufferScale.x); |
| int fb_height = (int)(draw_data->DisplaySize.y * draw_data->FramebufferScale.y); |
| if (fb_width <= 0 || fb_height <= 0) |
| return; |
| |
| // Backup GL state |
| GLenum last_active_texture; glGetIntegerv(GL_ACTIVE_TEXTURE, (GLint*)&last_active_texture); |
| glActiveTexture(GL_TEXTURE0); |
| GLint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, &last_program); |
| GLint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); |
| #ifdef GL_SAMPLER_BINDING |
| GLint last_sampler; glGetIntegerv(GL_SAMPLER_BINDING, &last_sampler); |
| #endif |
| GLint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer); |
| #ifndef IMGUI_IMPL_OPENGL_ES2 |
| GLint last_vertex_array_object; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array_object); |
| #endif |
| #ifdef GL_POLYGON_MODE |
| GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode); |
| #endif |
| GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport); |
| GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box); |
| GLenum last_blend_src_rgb; glGetIntegerv(GL_BLEND_SRC_RGB, (GLint*)&last_blend_src_rgb); |
| GLenum last_blend_dst_rgb; glGetIntegerv(GL_BLEND_DST_RGB, (GLint*)&last_blend_dst_rgb); |
| GLenum last_blend_src_alpha; glGetIntegerv(GL_BLEND_SRC_ALPHA, (GLint*)&last_blend_src_alpha); |
| GLenum last_blend_dst_alpha; glGetIntegerv(GL_BLEND_DST_ALPHA, (GLint*)&last_blend_dst_alpha); |
| GLenum last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, (GLint*)&last_blend_equation_rgb); |
| GLenum last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, (GLint*)&last_blend_equation_alpha); |
| GLboolean last_enable_blend = glIsEnabled(GL_BLEND); |
| GLboolean last_enable_cull_face = glIsEnabled(GL_CULL_FACE); |
| GLboolean last_enable_depth_test = glIsEnabled(GL_DEPTH_TEST); |
| GLboolean last_enable_scissor_test = glIsEnabled(GL_SCISSOR_TEST); |
| bool clip_origin_lower_left = true; |
| #if defined(GL_CLIP_ORIGIN) && !defined(__APPLE__) |
| GLenum last_clip_origin = 0; glGetIntegerv(GL_CLIP_ORIGIN, (GLint*)&last_clip_origin); // Support for GL 4.5's glClipControl(GL_UPPER_LEFT) |
| if (last_clip_origin == GL_UPPER_LEFT) |
| clip_origin_lower_left = false; |
| #endif |
| |
| // Setup desired GL state |
| // Recreate the VAO every time (this is to easily allow multiple GL contexts to be rendered to. VAO are not shared among GL contexts) |
| // The renderer would actually work without any VAO bound, but then our VertexAttrib calls would overwrite the default one currently bound. |
| GLuint vertex_array_object = 0; |
| #ifndef IMGUI_IMPL_OPENGL_ES2 |
| glGenVertexArrays(1, &vertex_array_object); |
| #endif |
| ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object); |
| |
| // Will project scissor/clipping rectangles into framebuffer space |
| ImVec2 clip_off = draw_data->DisplayPos; // (0,0) unless using multi-viewports |
| ImVec2 clip_scale = draw_data->FramebufferScale; // (1,1) unless using retina display which are often (2,2) |
| |
| // Render command lists |
| for (int n = 0; n < draw_data->CmdListsCount; n++) |
| { |
| const ImDrawList* cmd_list = draw_data->CmdLists[n]; |
| |
| // Upload vertex/index buffers |
| glBufferData(GL_ARRAY_BUFFER, (GLsizeiptr)cmd_list->VtxBuffer.Size * sizeof(ImDrawVert), (const GLvoid*)cmd_list->VtxBuffer.Data, GL_STREAM_DRAW); |
| glBufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx), (const GLvoid*)cmd_list->IdxBuffer.Data, GL_STREAM_DRAW); |
| |
| for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++) |
| { |
| const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i]; |
| if (pcmd->UserCallback != NULL) |
| { |
| // User callback, registered via ImDrawList::AddCallback() |
| // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.) |
| if (pcmd->UserCallback == ImDrawCallback_ResetRenderState) |
| ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object); |
| else |
| pcmd->UserCallback(cmd_list, pcmd); |
| } |
| else |
| { |
| // Project scissor/clipping rectangles into framebuffer space |
| ImVec4 clip_rect; |
| clip_rect.x = (pcmd->ClipRect.x - clip_off.x) * clip_scale.x; |
| clip_rect.y = (pcmd->ClipRect.y - clip_off.y) * clip_scale.y; |
| clip_rect.z = (pcmd->ClipRect.z - clip_off.x) * clip_scale.x; |
| clip_rect.w = (pcmd->ClipRect.w - clip_off.y) * clip_scale.y; |
| |
| if (clip_rect.x < fb_width && clip_rect.y < fb_height && clip_rect.z >= 0.0f && clip_rect.w >= 0.0f) |
| { |
| // Apply scissor/clipping rectangle |
| if (clip_origin_lower_left) |
| 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)); |
| else |
| glScissor((int)clip_rect.x, (int)clip_rect.y, (int)clip_rect.z, (int)clip_rect.w); // Support for GL 4.5 rarely used glClipControl(GL_UPPER_LEFT) |
| |
| // Bind texture, Draw |
| glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->TextureId); |
| #if IMGUI_IMPL_OPENGL_HAS_DRAW_WITH_BASE_VERTEX |
| glDrawElementsBaseVertex(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, (void*)(intptr_t)(pcmd->IdxOffset * sizeof(ImDrawIdx)), (GLint)pcmd->VtxOffset); |
| #else |
| glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, (void*)(intptr_t)(pcmd->IdxOffset * sizeof(ImDrawIdx))); |
| #endif |
| } |
| } |
| } |
| } |
| |
| // Destroy the temporary VAO |
| #ifndef IMGUI_IMPL_OPENGL_ES2 |
| glDeleteVertexArrays(1, &vertex_array_object); |
| #endif |
| |
| // Restore modified GL state |
| glUseProgram(last_program); |
| glBindTexture(GL_TEXTURE_2D, last_texture); |
| #ifdef GL_SAMPLER_BINDING |
| glBindSampler(0, last_sampler); |
| #endif |
| glActiveTexture(last_active_texture); |
| #ifndef IMGUI_IMPL_OPENGL_ES2 |
| glBindVertexArray(last_vertex_array_object); |
| #endif |
| glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer); |
| glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha); |
| glBlendFuncSeparate(last_blend_src_rgb, last_blend_dst_rgb, last_blend_src_alpha, last_blend_dst_alpha); |
| if (last_enable_blend) glEnable(GL_BLEND); else glDisable(GL_BLEND); |
| if (last_enable_cull_face) glEnable(GL_CULL_FACE); else glDisable(GL_CULL_FACE); |
| if (last_enable_depth_test) glEnable(GL_DEPTH_TEST); else glDisable(GL_DEPTH_TEST); |
| if (last_enable_scissor_test) glEnable(GL_SCISSOR_TEST); else glDisable(GL_SCISSOR_TEST); |
| #ifdef GL_POLYGON_MODE |
| glPolygonMode(GL_FRONT_AND_BACK, (GLenum)last_polygon_mode[0]); |
| #endif |
| glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]); |
| glScissor(last_scissor_box[0], last_scissor_box[1], (GLsizei)last_scissor_box[2], (GLsizei)last_scissor_box[3]); |
| } |
| |
| bool ImGui_ImplOpenGL3_CreateFontsTexture() |
| { |
| // Build texture atlas |
| ImGuiIO& io = ImGui::GetIO(); |
| unsigned char* pixels; |
| int width, height; |
| 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. |
| |
| // Upload texture to graphics system |
| GLint last_texture; |
| glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); |
| glGenTextures(1, &g_FontTexture); |
| glBindTexture(GL_TEXTURE_2D, g_FontTexture); |
| glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); |
| glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); |
| #ifdef GL_UNPACK_ROW_LENGTH |
| glPixelStorei(GL_UNPACK_ROW_LENGTH, 0); |
| #endif |
| glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels); |
| |
| // Store our identifier |
| io.Fonts->TexID = (ImTextureID)(intptr_t)g_FontTexture; |
| |
| // Restore state |
| glBindTexture(GL_TEXTURE_2D, last_texture); |
| |
| return true; |
| } |
| |
| void ImGui_ImplOpenGL3_DestroyFontsTexture() |
| { |
| if (g_FontTexture) |
| { |
| ImGuiIO& io = ImGui::GetIO(); |
| glDeleteTextures(1, &g_FontTexture); |
| io.Fonts->TexID = 0; |
| g_FontTexture = 0; |
| } |
| } |
| |
| // If you get an error please report on github. You may try different GL context version or GLSL version. See GL<>GLSL version table at the top of this file. |
| static bool CheckShader(GLuint handle, const char* desc) |
| { |
| GLint status = 0, log_length = 0; |
| glGetShaderiv(handle, GL_COMPILE_STATUS, &status); |
| glGetShaderiv(handle, GL_INFO_LOG_LENGTH, &log_length); |
| if ((GLboolean)status == GL_FALSE) |
| fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to compile %s!\n", desc); |
| if (log_length > 1) |
| { |
| ImVector<char> buf; |
| buf.resize((int)(log_length + 1)); |
| glGetShaderInfoLog(handle, log_length, NULL, (GLchar*)buf.begin()); |
| fprintf(stderr, "%s\n", buf.begin()); |
| } |
| return (GLboolean)status == GL_TRUE; |
| } |
| |
| // If you get an error please report on GitHub. You may try different GL context version or GLSL version. |
| static bool CheckProgram(GLuint handle, const char* desc) |
| { |
| GLint status = 0, log_length = 0; |
| glGetProgramiv(handle, GL_LINK_STATUS, &status); |
| glGetProgramiv(handle, GL_INFO_LOG_LENGTH, &log_length); |
| if ((GLboolean)status == GL_FALSE) |
| fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to link %s! (with GLSL '%s')\n", desc, g_GlslVersionString); |
| if (log_length > 1) |
| { |
| ImVector<char> buf; |
| buf.resize((int)(log_length + 1)); |
| glGetProgramInfoLog(handle, log_length, NULL, (GLchar*)buf.begin()); |
| fprintf(stderr, "%s\n", buf.begin()); |
| } |
| return (GLboolean)status == GL_TRUE; |
| } |
| |
| bool ImGui_ImplOpenGL3_CreateDeviceObjects() |
| { |
| // Backup GL state |
| GLint last_texture, last_array_buffer; |
| glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); |
| glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer); |
| #ifndef IMGUI_IMPL_OPENGL_ES2 |
| GLint last_vertex_array; |
| glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array); |
| #endif |
| |
| // Parse GLSL version string |
| int glsl_version = 130; |
| sscanf(g_GlslVersionString, "#version %d", &glsl_version); |
| |
| const GLchar* vertex_shader_glsl_120 = |
| "uniform mat4 ProjMtx;\n" |
| "attribute vec2 Position;\n" |
| "attribute vec2 UV;\n" |
| "attribute vec4 Color;\n" |
| "varying vec2 Frag_UV;\n" |
| "varying vec4 Frag_Color;\n" |
| "void main()\n" |
| "{\n" |
| " Frag_UV = UV;\n" |
| " Frag_Color = Color;\n" |
| " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" |
| "}\n"; |
| |
| const GLchar* vertex_shader_glsl_130 = |
| "uniform mat4 ProjMtx;\n" |
| "in vec2 Position;\n" |
| "in vec2 UV;\n" |
| "in vec4 Color;\n" |
| "out vec2 Frag_UV;\n" |
| "out vec4 Frag_Color;\n" |
| "void main()\n" |
| "{\n" |
| " Frag_UV = UV;\n" |
| " Frag_Color = Color;\n" |
| " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" |
| "}\n"; |
| |
| const GLchar* vertex_shader_glsl_300_es = |
| "precision mediump float;\n" |
| "layout (location = 0) in vec2 Position;\n" |
| "layout (location = 1) in vec2 UV;\n" |
| "layout (location = 2) in vec4 Color;\n" |
| "uniform mat4 ProjMtx;\n" |
| "out vec2 Frag_UV;\n" |
| "out vec4 Frag_Color;\n" |
| "void main()\n" |
| "{\n" |
| " Frag_UV = UV;\n" |
| " Frag_Color = Color;\n" |
| " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" |
| "}\n"; |
| |
| const GLchar* vertex_shader_glsl_410_core = |
| "layout (location = 0) in vec2 Position;\n" |
| "layout (location = 1) in vec2 UV;\n" |
| "layout (location = 2) in vec4 Color;\n" |
| "uniform mat4 ProjMtx;\n" |
| "out vec2 Frag_UV;\n" |
| "out vec4 Frag_Color;\n" |
| "void main()\n" |
| "{\n" |
| " Frag_UV = UV;\n" |
| " Frag_Color = Color;\n" |
| " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" |
| "}\n"; |
| |
| const GLchar* fragment_shader_glsl_120 = |
| "#ifdef GL_ES\n" |
| " precision mediump float;\n" |
| "#endif\n" |
| "uniform sampler2D Texture;\n" |
| "varying vec2 Frag_UV;\n" |
| "varying vec4 Frag_Color;\n" |
| "void main()\n" |
| "{\n" |
| " gl_FragColor = Frag_Color * texture2D(Texture, Frag_UV.st);\n" |
| "}\n"; |
| |
| const GLchar* fragment_shader_glsl_130 = |
| "uniform sampler2D Texture;\n" |
| "in vec2 Frag_UV;\n" |
| "in vec4 Frag_Color;\n" |
| "out vec4 Out_Color;\n" |
| "void main()\n" |
| "{\n" |
| " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n" |
| "}\n"; |
| |
| const GLchar* fragment_shader_glsl_300_es = |
| "precision mediump float;\n" |
| "uniform sampler2D Texture;\n" |
| "in vec2 Frag_UV;\n" |
| "in vec4 Frag_Color;\n" |
| "layout (location = 0) out vec4 Out_Color;\n" |
| "void main()\n" |
| "{\n" |
| " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n" |
| "}\n"; |
| |
| const GLchar* fragment_shader_glsl_410_core = |
| "in vec2 Frag_UV;\n" |
| "in vec4 Frag_Color;\n" |
| "uniform sampler2D Texture;\n" |
| "layout (location = 0) out vec4 Out_Color;\n" |
| "void main()\n" |
| "{\n" |
| " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n" |
| "}\n"; |
| |
| // Select shaders matching our GLSL versions |
| const GLchar* vertex_shader = NULL; |
| const GLchar* fragment_shader = NULL; |
| if (glsl_version < 130) |
| { |
| vertex_shader = vertex_shader_glsl_120; |
| fragment_shader = fragment_shader_glsl_120; |
| } |
| else if (glsl_version >= 410) |
| { |
| vertex_shader = vertex_shader_glsl_410_core; |
| fragment_shader = fragment_shader_glsl_410_core; |
| } |
| else if (glsl_version == 300) |
| { |
| vertex_shader = vertex_shader_glsl_300_es; |
| fragment_shader = fragment_shader_glsl_300_es; |
| } |
| else |
| { |
| vertex_shader = vertex_shader_glsl_130; |
| fragment_shader = fragment_shader_glsl_130; |
| } |
| |
| // Create shaders |
| const GLchar* vertex_shader_with_version[2] = { g_GlslVersionString, vertex_shader }; |
| g_VertHandle = glCreateShader(GL_VERTEX_SHADER); |
| glShaderSource(g_VertHandle, 2, vertex_shader_with_version, NULL); |
| glCompileShader(g_VertHandle); |
| CheckShader(g_VertHandle, "vertex shader"); |
| |
| const GLchar* fragment_shader_with_version[2] = { g_GlslVersionString, fragment_shader }; |
| g_FragHandle = glCreateShader(GL_FRAGMENT_SHADER); |
| glShaderSource(g_FragHandle, 2, fragment_shader_with_version, NULL); |
| glCompileShader(g_FragHandle); |
| CheckShader(g_FragHandle, "fragment shader"); |
| |
| g_ShaderHandle = glCreateProgram(); |
| glAttachShader(g_ShaderHandle, g_VertHandle); |
| glAttachShader(g_ShaderHandle, g_FragHandle); |
| glLinkProgram(g_ShaderHandle); |
| CheckProgram(g_ShaderHandle, "shader program"); |
| |
| g_AttribLocationTex = glGetUniformLocation(g_ShaderHandle, "Texture"); |
| g_AttribLocationProjMtx = glGetUniformLocation(g_ShaderHandle, "ProjMtx"); |
| g_AttribLocationVtxPos = glGetAttribLocation(g_ShaderHandle, "Position"); |
| g_AttribLocationVtxUV = glGetAttribLocation(g_ShaderHandle, "UV"); |
| g_AttribLocationVtxColor = glGetAttribLocation(g_ShaderHandle, "Color"); |
| |
| // Create buffers |
| glGenBuffers(1, &g_VboHandle); |
| glGenBuffers(1, &g_ElementsHandle); |
| |
| ImGui_ImplOpenGL3_CreateFontsTexture(); |
| |
| // Restore modified GL state |
| glBindTexture(GL_TEXTURE_2D, last_texture); |
| glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer); |
| #ifndef IMGUI_IMPL_OPENGL_ES2 |
| glBindVertexArray(last_vertex_array); |
| #endif |
| |
| return true; |
| } |
| |
| void ImGui_ImplOpenGL3_DestroyDeviceObjects() |
| { |
| if (g_VboHandle) glDeleteBuffers(1, &g_VboHandle); |
| if (g_ElementsHandle) glDeleteBuffers(1, &g_ElementsHandle); |
| g_VboHandle = g_ElementsHandle = 0; |
| |
| if (g_ShaderHandle && g_VertHandle) glDetachShader(g_ShaderHandle, g_VertHandle); |
| if (g_VertHandle) glDeleteShader(g_VertHandle); |
| g_VertHandle = 0; |
| |
| if (g_ShaderHandle && g_FragHandle) glDetachShader(g_ShaderHandle, g_FragHandle); |
| if (g_FragHandle) glDeleteShader(g_FragHandle); |
| g_FragHandle = 0; |
| |
| if (g_ShaderHandle) glDeleteProgram(g_ShaderHandle); |
| g_ShaderHandle = 0; |
| |
| ImGui_ImplOpenGL3_DestroyFontsTexture(); |
| } |
