Previous SDL implementation didn't work with my OpenGL 3.3 project, spliced the GLFW OpenGL examples on top of the SDL example to create an option that works for me. Could be useful for others.

2025-07-12 15:59:54 +02:00 · 2015-09-30 15:12:00 +01:00
parent a76b75c2d5
commit e130b09d91
4 changed files with 509 additions and 0 deletions
--- a/examples/sdl_opengl3_example/main.cpp
+++ b/examples/sdl_opengl3_example/main.cpp
@ -0,0 +1,108 @@
+// ImGui - standalone example application for SDL2 + OpenGL
+
+#include <imgui.h>
+#include "imgui_impl_sdlogl3.h"
+#include <stdio.h>
+#include <SDL.h>
+#include <GL/glew.h>
+
+int main(int, char**)
+{
+    // Setup SDL
+	if (SDL_Init(SDL_INIT_EVERYTHING) != 0)
+	{
+        printf("Error: %s\n", SDL_GetError());
+        return -1;
+	}
+
+    // Setup window
+	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
+	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
+	SDL_DisplayMode current;
+	SDL_GetCurrentDisplayMode(0, &current);
+	SDL_Window *window = SDL_CreateWindow("ImGui SDL2+OpenGL example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
+	SDL_GLContext glcontext = SDL_GL_CreateContext(window);
+
+    // Setup ImGui binding
+    ImGui_ImplSdlOgl3_Init(window);
+
+    // Load Fonts
+    // (see extra_fonts/README.txt for more details)
+    //ImGuiIO& io = ImGui::GetIO();
+    //io.Fonts->AddFontDefault();
+    //io.Fonts->AddFontFromFileTTF("../../extra_fonts/Cousine-Regular.ttf", 15.0f);
+    //io.Fonts->AddFontFromFileTTF("../../extra_fonts/DroidSans.ttf", 16.0f);
+    //io.Fonts->AddFontFromFileTTF("../../extra_fonts/ProggyClean.ttf", 13.0f);
+    //io.Fonts->AddFontFromFileTTF("../../extra_fonts/ProggyTiny.ttf", 10.0f);
+    //io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese());
+
+    // Merge glyphs from multiple fonts into one (e.g. combine default font with another with Chinese glyphs, or add icons)
+    //ImWchar icons_ranges[] = { 0xf000, 0xf3ff, 0 };
+    //ImFontConfig icons_config; icons_config.MergeMode = true; icons_config.PixelSnapH = true;
+    //io.Fonts->AddFontFromFileTTF("../../extra_fonts/DroidSans.ttf", 18.0f);
+    //io.Fonts->AddFontFromFileTTF("../../extra_fonts/fontawesome-webfont.ttf", 18.0f, &icons_config, icons_ranges);
+
+    bool show_test_window = true;
+    bool show_another_window = false;
+    ImVec4 clear_color = ImColor(114, 144, 154);
+
+    // Main loop
+	bool done = false;
+    while (!done)
+    {
+        SDL_Event event;
+        while (SDL_PollEvent(&event))
+        {
+            ImGui_ImplSdlOgl3_ProcessEvent(&event);
+            if (event.type == SDL_QUIT)
+                done = true;
+        }
+        ImGui_ImplSdlOgl3_NewFrame(window);
+
+        // 1. Show a simple window
+        // Tip: if we don't call ImGui::Begin()/ImGui::End() the widgets appears in a window automatically called "Debug"
+        {
+            static float f = 0.0f;
+            ImGui::Text("Hello, world!");
+            ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
+            ImGui::ColorEdit3("clear color", (float*)&clear_color);
+            if (ImGui::Button("Test Window")) show_test_window ^= 1;
+            if (ImGui::Button("Another Window")) show_another_window ^= 1;
+            ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate);
+        }
+
+        // 2. Show another simple window, this time using an explicit Begin/End pair
+        if (show_another_window)
+        {
+            ImGui::SetNextWindowSize(ImVec2(200,100), ImGuiSetCond_FirstUseEver);
+            ImGui::Begin("Another Window", &show_another_window);
+            ImGui::Text("Hello");
+            ImGui::End();
+        }
+
+        // 3. Show the ImGui test window. Most of the sample code is in ImGui::ShowTestWindow()
+        if (show_test_window)
+        {
+            ImGui::SetNextWindowPos(ImVec2(650, 20), ImGuiSetCond_FirstUseEver);
+            ImGui::ShowTestWindow(&show_test_window);
+        }
+
+        // Rendering
+        glViewport(0, 0, (int)ImGui::GetIO().DisplaySize.x, (int)ImGui::GetIO().DisplaySize.y);
+        glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
+        glClear(GL_COLOR_BUFFER_BIT);
+        ImGui::Render();
+        SDL_GL_SwapWindow(window);
+    }
+
+    // Cleanup
+    ImGui_ImplSdlOgl3_Shutdown();
+    SDL_GL_DeleteContext(glcontext);  
+	SDL_DestroyWindow(window);
+	SDL_Quit();
+
+    return 0;
+}