main.cpp

#include <iostream>

#include "GL/glew.h"
#include "GLFW/glfw3.h"
#include "imgui.h"
#include "backends/imgui_impl_glfw.h"
#include "backends/imgui_impl_opengl3.h"

static void helloWorld() {
	ImGui::Begin("My DearImGui Window");
	ImGui::Text("hello, world");
	ImGui::End();
}

int main() {

	// Setup window
	glfwSetErrorCallback([](int error, const char* description) {
		fprintf(stderr, "Glfw Error %d: %s\n", error, description);
	});
	glfwInit();

	// GL 3.0 + GLSL 130
	const char* glsl_version = "#version 130";
	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);

	// Create window with graphics context
	GLFWwindow* window = glfwCreateWindow(800, 600, "My GLFW Window", nullptr, nullptr);
	glfwMakeContextCurrent(window);
	glfwSwapInterval(1); // Enable vsync

	// Initialize OpenGL loader
	glewInit();

	// Setup Dear ImGui context
	IMGUI_CHECKVERSION();
	ImGui::CreateContext();

	// Setup Dear ImGui style
	ImGui::StyleColorsDark();

	// Setup Platform/Renderer bindings
	ImGui_ImplGlfw_InitForOpenGL(window, true);
	ImGui_ImplOpenGL3_Init(glsl_version);

	// Main loop
	int display_w, display_h;
	glfwGetFramebufferSize(window, &display_w, &display_h);

	while (!glfwWindowShouldClose(window)) {
		// Poll and handle events (inputs, window resize, etc.)
		glfwPollEvents();

		// Start the Dear ImGui frame
		ImGui_ImplOpenGL3_NewFrame();
		ImGui_ImplGlfw_NewFrame();
		ImGui::NewFrame();

		// Run our Dear ImGui application
		helloWorld();

		// Rendering
		ImGui::Render();
		glfwGetFramebufferSize(window, &display_w, &display_h);
		glViewport(0, 0, display_w, display_h);
		glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
		glClear(GL_COLOR_BUFFER_BIT);
		ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
		glfwSwapBuffers(window);
	}

	// Cleanup
	ImGui_ImplOpenGL3_Shutdown();
	ImGui_ImplGlfw_Shutdown();
	ImGui::DestroyContext();

	glfwDestroyWindow(window);
	glfwTerminate();
}