594 lines
26 KiB
C++
594 lines
26 KiB
C++
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// dear imgui: Renderer for OpenGL3 / OpenGL ES2 / OpenGL ES3 (modern OpenGL with shaders / programmatic pipeline)
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// This needs to be used along with a Platform Binding (e.g. GLFW, SDL, Win32, custom..)
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// (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..)
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// Implemented features:
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// [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID in imgui.cpp.
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// [X] Renderer: Multi-viewport support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
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// You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
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// If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.
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// https://github.com/ocornut/imgui
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// CHANGELOG
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// (minor and older changes stripped away, please see git history for details)
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// 2018-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
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// 2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
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// 2018-11-13: OpenGL: Support for GL 4.5's glClipControl(GL_UPPER_LEFT).
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// 2018-08-29: OpenGL: Added support for more OpenGL loaders: glew and glad, with comments indicative that any loader can be used.
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// 2018-08-09: OpenGL: Default to OpenGL ES 3 on iOS and Android. GLSL version default to "#version 300 ES".
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// 2018-07-30: OpenGL: Support for GLSL 300 ES and 410 core. Fixes for Emscripten compilation.
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// 2018-07-10: OpenGL: Support for more GLSL versions (based on the GLSL version string). Added error output when shaders fail to compile/link.
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// 2018-06-08: Misc: Extracted imgui_impl_opengl3.cpp/.h away from the old combined GLFW/SDL+OpenGL3 examples.
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// 2018-06-08: OpenGL: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
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// 2018-05-25: OpenGL: Removed unnecessary backup/restore of GL_ELEMENT_ARRAY_BUFFER_BINDING since this is part of the VAO state.
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// 2018-05-14: OpenGL: Making the call to glBindSampler() optional so 3.2 context won't fail if the function is a NULL pointer.
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// 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".
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// 2018-02-23: OpenGL: Create the VAO in the render function so the setup can more easily be used with multiple shared GL context.
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// 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplSdlGL3_RenderDrawData() in the .h file so you can call it yourself.
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// 2018-01-07: OpenGL: Changed GLSL shader version from 330 to 150.
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// 2017-09-01: OpenGL: Save and restore current bound sampler. Save and restore current polygon mode.
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// 2017-05-01: OpenGL: Fixed save and restore of current blend func state.
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// 2017-05-01: OpenGL: Fixed save and restore of current GL_ACTIVE_TEXTURE.
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// 2016-09-05: OpenGL: Fixed save and restore of current scissor rectangle.
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// 2016-07-29: OpenGL: Explicitly setting GL_UNPACK_ROW_LENGTH to reduce issues because SDL changes it. (#752)
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//----------------------------------------
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// OpenGL GLSL GLSL
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// version version string
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//----------------------------------------
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// 2.0 110 "#version 110"
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// 2.1 120
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// 3.0 130
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// 3.1 140
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// 3.2 150 "#version 150"
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// 3.3 330
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// 4.0 400
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// 4.1 410 "#version 410 core"
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// 4.2 420
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// 4.3 430
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// ES 2.0 100 "#version 100"
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// ES 3.0 300 "#version 300 es"
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//----------------------------------------
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#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
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#define _CRT_SECURE_NO_WARNINGS
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#endif
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#include "imgui.h"
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#include "imgui_impl_opengl3.h"
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#include <stdio.h>
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#if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier
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#include <stddef.h> // intptr_t
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#else
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#include <stdint.h> // intptr_t
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#endif
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#if defined(__APPLE__)
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#include "TargetConditionals.h"
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#endif
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// iOS, Android and Emscripten can use GL ES 3
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// Call ImGui_ImplOpenGL3_Init() with "#version 300 es"
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#if (defined(__APPLE__) && TARGET_OS_IOS) || (defined(__ANDROID__)) || (defined(__EMSCRIPTEN__))
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#define USE_GL_ES3
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#endif
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#ifdef USE_GL_ES3
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// OpenGL ES 3
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#include <GLES3/gl3.h> // Use GL ES 3
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#else
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// Regular OpenGL
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// About OpenGL function loaders: modern OpenGL doesn't have a standard header file and requires individual function pointers to be loaded manually.
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// Helper libraries are often used for this purpose! Here we are supporting a few common ones: gl3w, glew, glad.
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// You may use another loader/header of your choice (glext, glLoadGen, etc.), or chose to manually implement your own.
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#if defined(IMGUI_IMPL_OPENGL_LOADER_GL3W)
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#include <GL/gl3w.h>
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLEW)
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#include <GL/glew.h>
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD)
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#include <glad/glad.h>
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#else
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#include IMGUI_IMPL_OPENGL_LOADER_CUSTOM
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#endif
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#endif
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// OpenGL Data
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static char g_GlslVersionString[32] = "";
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static GLuint g_FontTexture = 0;
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static GLuint g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0;
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static int g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0;
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static int g_AttribLocationPosition = 0, g_AttribLocationUV = 0, g_AttribLocationColor = 0;
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static unsigned int g_VboHandle = 0, g_ElementsHandle = 0;
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// Forward Declarations
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static void ImGui_ImplOpenGL3_InitPlatformInterface();
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static void ImGui_ImplOpenGL3_ShutdownPlatformInterface();
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// Functions
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bool ImGui_ImplOpenGL3_Init(const char* glsl_version)
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{
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// Setup back-end capabilities flags
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ImGuiIO& io = ImGui::GetIO();
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io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports; // We can create multi-viewports on the Renderer side (optional)
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io.BackendRendererName = "imgui_impl_opengl3";
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// 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.
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#ifdef USE_GL_ES3
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if (glsl_version == NULL)
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glsl_version = "#version 300 es";
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#else
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if (glsl_version == NULL)
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glsl_version = "#version 130";
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#endif
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IM_ASSERT((int)strlen(glsl_version) + 2 < IM_ARRAYSIZE(g_GlslVersionString));
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strcpy(g_GlslVersionString, glsl_version);
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strcat(g_GlslVersionString, "\n");
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if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
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ImGui_ImplOpenGL3_InitPlatformInterface();
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return true;
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}
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void ImGui_ImplOpenGL3_Shutdown()
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{
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ImGui_ImplOpenGL3_ShutdownPlatformInterface();
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ImGui_ImplOpenGL3_DestroyDeviceObjects();
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}
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void ImGui_ImplOpenGL3_NewFrame()
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{
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if (!g_FontTexture)
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ImGui_ImplOpenGL3_CreateDeviceObjects();
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}
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// OpenGL3 Render function.
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// (this used to be set in io.RenderDrawListsFn and called by ImGui::Render(), but you can now call this directly from your main loop)
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// 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.
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void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
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{
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// Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
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ImGuiIO& io = ImGui::GetIO();
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int fb_width = (int)(draw_data->DisplaySize.x * io.DisplayFramebufferScale.x);
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int fb_height = (int)(draw_data->DisplaySize.y * io.DisplayFramebufferScale.y);
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if (fb_width <= 0 || fb_height <= 0)
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return;
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draw_data->ScaleClipRects(io.DisplayFramebufferScale);
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// Backup GL state
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GLenum last_active_texture; glGetIntegerv(GL_ACTIVE_TEXTURE, (GLint*)&last_active_texture);
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glActiveTexture(GL_TEXTURE0);
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GLint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
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GLint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
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#ifdef GL_SAMPLER_BINDING
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GLint last_sampler; glGetIntegerv(GL_SAMPLER_BINDING, &last_sampler);
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#endif
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GLint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
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GLint last_vertex_array; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
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#ifdef GL_POLYGON_MODE
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GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
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#endif
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GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
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GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box);
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GLenum last_blend_src_rgb; glGetIntegerv(GL_BLEND_SRC_RGB, (GLint*)&last_blend_src_rgb);
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GLenum last_blend_dst_rgb; glGetIntegerv(GL_BLEND_DST_RGB, (GLint*)&last_blend_dst_rgb);
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GLenum last_blend_src_alpha; glGetIntegerv(GL_BLEND_SRC_ALPHA, (GLint*)&last_blend_src_alpha);
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GLenum last_blend_dst_alpha; glGetIntegerv(GL_BLEND_DST_ALPHA, (GLint*)&last_blend_dst_alpha);
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GLenum last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, (GLint*)&last_blend_equation_rgb);
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GLenum last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, (GLint*)&last_blend_equation_alpha);
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GLboolean last_enable_blend = glIsEnabled(GL_BLEND);
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GLboolean last_enable_cull_face = glIsEnabled(GL_CULL_FACE);
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GLboolean last_enable_depth_test = glIsEnabled(GL_DEPTH_TEST);
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GLboolean last_enable_scissor_test = glIsEnabled(GL_SCISSOR_TEST);
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bool clip_origin_lower_left = true;
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#ifdef GL_CLIP_ORIGIN
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GLenum last_clip_origin = 0; glGetIntegerv(GL_CLIP_ORIGIN, (GLint*)&last_clip_origin); // Support for GL 4.5's glClipControl(GL_UPPER_LEFT)
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if (last_clip_origin == GL_UPPER_LEFT)
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clip_origin_lower_left = false;
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#endif
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// Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill
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glEnable(GL_BLEND);
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glBlendEquation(GL_FUNC_ADD);
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glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
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glDisable(GL_CULL_FACE);
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glDisable(GL_DEPTH_TEST);
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glEnable(GL_SCISSOR_TEST);
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#ifdef GL_POLYGON_MODE
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glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
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#endif
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// Setup viewport, orthographic projection matrix
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// Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayMin is (0,0) for single viewport apps.
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glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height);
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float L = draw_data->DisplayPos.x;
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float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
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float T = draw_data->DisplayPos.y;
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float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
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const float ortho_projection[4][4] =
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{
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{ 2.0f/(R-L), 0.0f, 0.0f, 0.0f },
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{ 0.0f, 2.0f/(T-B), 0.0f, 0.0f },
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{ 0.0f, 0.0f, -1.0f, 0.0f },
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{ (R+L)/(L-R), (T+B)/(B-T), 0.0f, 1.0f },
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};
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glUseProgram(g_ShaderHandle);
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glUniform1i(g_AttribLocationTex, 0);
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glUniformMatrix4fv(g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]);
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#ifdef GL_SAMPLER_BINDING
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glBindSampler(0, 0); // We use combined texture/sampler state. Applications using GL 3.3 may set that otherwise.
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#endif
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// Recreate the VAO every time
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// (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.)
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GLuint vao_handle = 0;
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glGenVertexArrays(1, &vao_handle);
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glBindVertexArray(vao_handle);
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glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
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glEnableVertexAttribArray(g_AttribLocationPosition);
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glEnableVertexAttribArray(g_AttribLocationUV);
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glEnableVertexAttribArray(g_AttribLocationColor);
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glVertexAttribPointer(g_AttribLocationPosition, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, pos));
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glVertexAttribPointer(g_AttribLocationUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, uv));
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glVertexAttribPointer(g_AttribLocationColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, col));
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// Draw
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ImVec2 pos = draw_data->DisplayPos;
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for (int n = 0; n < draw_data->CmdListsCount; n++)
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{
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const ImDrawList* cmd_list = draw_data->CmdLists[n];
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const ImDrawIdx* idx_buffer_offset = 0;
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glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
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glBufferData(GL_ARRAY_BUFFER, (GLsizeiptr)cmd_list->VtxBuffer.Size * sizeof(ImDrawVert), (const GLvoid*)cmd_list->VtxBuffer.Data, GL_STREAM_DRAW);
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glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ElementsHandle);
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glBufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx), (const GLvoid*)cmd_list->IdxBuffer.Data, GL_STREAM_DRAW);
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for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
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{
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const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
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if (pcmd->UserCallback)
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{
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// User callback (registered via ImDrawList::AddCallback)
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pcmd->UserCallback(cmd_list, pcmd);
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}
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else
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{
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ImVec4 clip_rect = ImVec4(pcmd->ClipRect.x - pos.x, pcmd->ClipRect.y - pos.y, pcmd->ClipRect.z - pos.x, pcmd->ClipRect.w - pos.y);
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if (clip_rect.x < fb_width && clip_rect.y < fb_height && clip_rect.z >= 0.0f && clip_rect.w >= 0.0f)
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{
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// Apply scissor/clipping rectangle
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if (clip_origin_lower_left)
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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));
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else
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glScissor((int)clip_rect.x, (int)clip_rect.y, (int)clip_rect.z, (int)clip_rect.w); // Support for GL 4.5's glClipControl(GL_UPPER_LEFT)
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// Bind texture, Draw
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glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->TextureId);
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glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer_offset);
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}
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}
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idx_buffer_offset += pcmd->ElemCount;
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}
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}
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glDeleteVertexArrays(1, &vao_handle);
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// Restore modified GL state
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glUseProgram(last_program);
|
||
|
|
glBindTexture(GL_TEXTURE_2D, last_texture);
|
||
|
|
#ifdef GL_SAMPLER_BINDING
|
||
|
|
glBindSampler(0, last_sampler);
|
||
|
|
#endif
|
||
|
|
glActiveTexture(last_active_texture);
|
||
|
|
glBindVertexArray(last_vertex_array);
|
||
|
|
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);
|
||
|
|
glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
|
||
|
|
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 > 0)
|
||
|
|
{
|
||
|
|
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 > 0)
|
||
|
|
{
|
||
|
|
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, last_vertex_array;
|
||
|
|
glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
|
||
|
|
glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
|
||
|
|
glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
|
||
|
|
|
||
|
|
// 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_AttribLocationPosition = glGetAttribLocation(g_ShaderHandle, "Position");
|
||
|
|
g_AttribLocationUV = glGetAttribLocation(g_ShaderHandle, "UV");
|
||
|
|
g_AttribLocationColor = 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);
|
||
|
|
glBindVertexArray(last_vertex_array);
|
||
|
|
|
||
|
|
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();
|
||
|
|
}
|
||
|
|
|
||
|
|
//--------------------------------------------------------------------------------------------------------
|
||
|
|
// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
|
||
|
|
// This is an _advanced_ and _optional_ feature, allowing the back-end to create and handle multiple viewports simultaneously.
|
||
|
|
// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
|
||
|
|
//--------------------------------------------------------------------------------------------------------
|
||
|
|
|
||
|
|
static void ImGui_ImplOpenGL3_RenderWindow(ImGuiViewport* viewport, void*)
|
||
|
|
{
|
||
|
|
if (!(viewport->Flags & ImGuiViewportFlags_NoRendererClear))
|
||
|
|
{
|
||
|
|
ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
|
||
|
|
glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
|
||
|
|
glClear(GL_COLOR_BUFFER_BIT);
|
||
|
|
}
|
||
|
|
ImGui_ImplOpenGL3_RenderDrawData(viewport->DrawData);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void ImGui_ImplOpenGL3_InitPlatformInterface()
|
||
|
|
{
|
||
|
|
ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
|
||
|
|
platform_io.Renderer_RenderWindow = ImGui_ImplOpenGL3_RenderWindow;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void ImGui_ImplOpenGL3_ShutdownPlatformInterface()
|
||
|
|
{
|
||
|
|
ImGui::DestroyPlatformWindows();
|
||
|
|
}
|