1 files changed, 113 insertions, 0 deletions
diff --git a/core/src/Entrypoint/Backend_OpenGL3.cpp b/core/src/Entrypoint/Backend_OpenGL3.cpp
new file mode 100644
index 0000000..36a0cb3
--- /dev/null
+++ b/core/src/Entrypoint/Backend_OpenGL3.cpp
@@ -0,0 +1,113 @@
+#include "Entrypoint/Backend.hpp"
+
+#if BUILD_CORE_WITH_OPENGL3_BACKEND
+#	include <glad/glad.h>
+#	include <GLFW/glfw3.h>
+#	include <iostream>
+#	include <backend/imgui_impl_glfw.h>
+#	include <backend/imgui_impl_opengl3.h>
+#	include <imgui.h>
+#	include <stdexcept>
+
+#	define IMGUI_IMPL_OPENGL_LOADER_GLAD
+#	include <backend/imgui_impl_opengl3.cpp>
+
+class OpenGL3Backend : public RenderingBackend {
+private:
+	GLFWwindow* mWindow;
+
+public:
+	OpenGL3Backend() {
+		glfwSetErrorCallback(&GlfwErrorCallback);
+		if (!glfwInit()) {
+			throw std::runtime_error("Failed to initialize GLFW.");
+		}
+
+#	if PLATFORM_APPLE
+		// GL 3.2 + GLSL 150
+		const char* glslVersion = "#version 150";
+		glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+		glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2);
+		glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); // 3.2+ only
+		glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); // Required on Mac
+#	else
+		// GL 3.0 + GLSL 130
+		const char* glslVersion = "#version 130";
+		glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+		glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
+		//glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);  // 3.2+ only
+		//glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);            // 3.0+ only
+#	endif
+
+		mWindow = glfwCreateWindow(1280, 720, "Cplt", nullptr, nullptr);
+		if (mWindow == nullptr) {
+			throw std::runtime_error("Failed to create GLFW window.");
+		}
+		glfwMakeContextCurrent(mWindow);
+		glfwSwapInterval(1); // Enable vsync
+
+		if (gladLoadGLLoader((GLADloadproc)glfwGetProcAddress) == 0) {
+			throw std::runtime_error("Failed to initialize OpenGL.");
+		}
+
+		IMGUI_CHECKVERSION();
+		ImGui::CreateContext();
+
+		ImGui_ImplGlfw_InitForOpenGL(mWindow, true);
+		ImGui_ImplOpenGL3_Init(glslVersion);
+	}
+
+	virtual ~OpenGL3Backend() {
+		ImGui_ImplOpenGL3_Shutdown();
+		ImGui_ImplGlfw_Shutdown();
+		ImGui::DestroyContext();
+
+		glfwDestroyWindow(mWindow);
+		glfwTerminate();
+	}
+
+	virtual void RunUntilWindowClose(void (*windowContent)()) {
+		while (!glfwWindowShouldClose(mWindow)) {
+			glfwPollEvents();
+
+			ImGui_ImplOpenGL3_NewFrame();
+			ImGui_ImplGlfw_NewFrame();
+			ImGui::NewFrame();
+
+			windowContent();
+
+			int displayWidth, displayHeight;
+			glfwGetFramebufferSize(mWindow, &displayWidth, &displayHeight);
+			glViewport(0, 0, displayWidth, displayHeight);
+
+			const ImVec4 kClearColor = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
+			glClearColor(kClearColor.x * kClearColor.w, kClearColor.y * kClearColor.w, kClearColor.z * kClearColor.w, kClearColor.w);
+			glClear(GL_COLOR_BUFFER_BIT);
+
+			ImGui::Render();
+			ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+
+			glfwSwapBuffers(mWindow);
+		}
+	}
+
+	static void GlfwErrorCallback(int errorCode, const char* message) {
+		std::cerr << "GLFW Error " << errorCode << ": " << message << "\n";
+	}
+};
+
+std::unique_ptr<RenderingBackend> RenderingBackend::CreateOpenGL3Backend() {
+	try {
+		return std::make_unique<OpenGL3Backend>();
+	} catch (std::exception& e) {
+		return nullptr;
+	}
+}
+
+#else // ^^ BUILD_CORE_WITH_OPENGL3_BACKEND | !BUILD_CORE_WITH_OPENGL3_BACKEND vv
+
+std::unique_ptr<RenderingBackend> RenderingBackend::CreateOpenGL3Backend() {
+	return nullptr;
+}
+
+#endif