restructure work

engine/Backend/Backend.h

@@ -0,0 +1,21 @@
+
+#pragma once
+
+#include <iostream>
+#include <glad/glad.h>
+#include <glfw/include/GLFW/glfw3.h>
+
+namespace engine::Backend
+{
+    void window_resize_callback(GLFWwindow* window, int width, int height);
+    void mouse_callback(GLFWwindow* window, double xpos, double ypos);
+    void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
+    void processInput(GLFWwindow *window);
+    bool isWindowOpen();
+
+    void PreFrame();
+    void PostFrame();
+
+    bool Init(const char* title, int width, int height);
+    void Cleanup();
+}