Initial Commit

Basic window with OpenGL, glad, GLFW, ImGui, and Eigen. Dependencies are populated with FetchContent, not submodules.
2025-11-10 03:52:48 -05:00 · 2022-02-07 21:45:09 -05:00
commit 2f17710adb
7 changed files with 235 additions and 0 deletions
--- a/main.cpp
+++ b/main.cpp
@@ -0,0 +1,123 @@
+#include <glad/glad.h>
+#include <GLFW/glfw3.h>
+#include <imgui.h>
+#include <backends/imgui_impl_glfw.h>
+#include <backends/imgui_impl_opengl3.h>
+#include <iostream>
+
+void show_overlay() {
+    ImGuiWindowFlags window_flags = ImGuiWindowFlags_None
+        | ImGuiWindowFlags_NoDecoration
+        | ImGuiWindowFlags_AlwaysAutoResize
+        | ImGuiWindowFlags_NoSavedSettings
+        | ImGuiWindowFlags_NoFocusOnAppearing
+        | ImGuiWindowFlags_NoNav
+        | ImGuiWindowFlags_NoMove;
+    ImGuiStyle &style = ImGui::GetStyle();
+    const auto PAD = style.DisplaySafeAreaPadding;
+    const auto *viewport = ImGui::GetMainViewport();
+    const auto work_pos = viewport->WorkPos;
+    const auto work_size = viewport->WorkSize;
+    const auto window_pos = ImVec2(
+        work_pos.x + PAD.x,
+        work_pos.y + PAD.y
+    );
+    const auto window_pos_pivot = ImVec2(
+        0.0f,
+        0.0f
+    );
+    ImGui::SetNextWindowPos(
+        window_pos,
+        ImGuiCond_Always,
+        window_pos_pivot
+    );
+    ImGui::SetNextWindowBgAlpha(0.35f * style.Alpha);
+    if (ImGui::Begin("Graphics Information", nullptr, window_flags)) {
+        ImGui::BeginTable("graphics", 2, ImGuiTableFlags_BordersInnerV);
+        ImGui::TableNextRow();
+        ImGui::TableNextColumn();
+        ImGui::Text("GL Vendor");
+        ImGui::TableNextColumn();
+        ImGui::Text("%s", glGetString(GL_VENDOR));
+        ImGui::TableNextRow();
+        ImGui::TableNextColumn();
+        ImGui::Text("GL Renderer");
+        ImGui::TableNextColumn();
+        ImGui::Text("%s", glGetString(GL_RENDERER));
+        ImGui::TableNextRow();
+        ImGui::TableNextColumn();
+        ImGui::Text("GL Version");
+        ImGui::TableNextColumn();
+        ImGui::Text("%s", glGetString(GL_VERSION));
+        ImGui::TableNextRow();
+        ImGui::TableNextColumn();
+        ImGui::Text("GLSL Version");
+        ImGui::TableNextColumn();
+        ImGui::Text("%s", glGetString(GL_SHADING_LANGUAGE_VERSION));
+        ImGui::EndTable();
+        ImGui::End();
+    }
+}
+
+int main() {
+    if (!glfwInit()) {
+        std::cerr << "GLFW :: failed initialization" << std::endl;
+        exit(EXIT_FAILURE);
+    }
+
+    const char *glsl_version = "#version 130";
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
+    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
+    auto *window = glfwCreateWindow(1280, 720, "Hello OpenGL", nullptr, nullptr);
+    if (!window) {
+        std::cerr << "GLFW :: failed to create window" << std::endl;
+        exit(EXIT_FAILURE);
+    }
+
+    glfwMakeContextCurrent(window);
+    glfwSwapInterval(1);
+    gladLoadGLLoader((GLADloadproc) glfwGetProcAddress);
+
+    IMGUI_CHECKVERSION();
+    ImGui::CreateContext();
+    ImGuiIO &io = ImGui::GetIO();
+
+    ImGui::StyleColorsDark();
+
+    ImGui_ImplGlfw_InitForOpenGL(window, true);
+    ImGui_ImplOpenGL3_Init(glsl_version);
+
+    io.Fonts->AddFontDefault();
+
+    ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
+
+    while (!glfwWindowShouldClose(window)) {
+        glfwPollEvents();
+
+        ImGui_ImplOpenGL3_NewFrame();
+        ImGui_ImplGlfw_NewFrame();
+        ImGui::NewFrame();
+        show_overlay();
+        ImGui::Render();
+
+        int display_w, display_h;
+        glfwGetFramebufferSize(window, &display_w, &display_h);
+        glViewport(0, 0, display_w, display_h);
+        glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w,
+            clear_color.w);
+        glClear(GL_COLOR_BUFFER_BIT);
+        ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+
+        glfwSwapBuffers(window);
+    }
+
+    ImGui_ImplOpenGL3_Shutdown();
+    ImGui_ImplGlfw_Shutdown();
+    ImGui::DestroyContext();
+
+    glfwDestroyWindow(window);
+    glfwTerminate();
+
+    exit(EXIT_SUCCESS);
+}