[ChatGPT][LWJGL3][게임개발] LWJGL Game loop 샘플 예제 코드

LWJGL Game loop 샘플 예제 코드

/* Here is an example of a game loop in LWJGL */
import org.lwjgl.glfw.*;
import org.lwjgl.opengl.*;
import org.lwjgl.system.*;

import java.nio.*;

import static org.lwjgl.glfw.Callbacks.*;
import static org.lwjgl.glfw.GLFW.*;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.system.MemoryStack.*;
import static org.lwjgl.system.MemoryUtil.*;

public class Game {

    // The window handle
    private long window;
    private boolean running = true;

    public void run() {
        init();
        loop();

        // Free the window callbacks and destroy the window
        glfwFreeCallbacks(window);
        glfwDestroyWindow(window);

        // Terminate GLFW and free the error callback
        glfwTerminate();
        glfwSetErrorCallback(null).free();
    }

    private void init() {
        // Initialize GLFW
        glfwInit();

        // Configure GLFW
        glfwWindowHint(GLFW_RESIZABLE, GLFW_FALSE);

        // Create the window
        window = glfwCreateWindow(800, 600, "My Game", NULL, NULL);
        if ( window == NULL )
            throw new RuntimeException("Failed to create the GLFW window");

        // Setup a key callback. It will be called every time a key is pressed, repeated or released.
        glfwSetKeyCallback(window, (window, key, scancode, action, mods) -> {
            if ( key == GLFW_KEY_ESCAPE && action == GLFW_RELEASE )
                running = false;
        });

        // Get the thread stack and push a new frame
        try ( MemoryStack stack = stackPush() ) {
            IntBuffer pWidth = stack.mallocInt(1); // int*
            IntBuffer pHeight = stack.mallocInt(1); // int*

            // Get the window size passed to glfwCreateWindow
            glfwGetWindowSize(window, pWidth, pHeight);

            // Get the resolution of the primary monitor
            GLFWVidMode vidmode = glfwGetVideoMode(glfwGetPrimaryMonitor());

            // Center the window
            glfwSetWindowPos(
                window,
                (vidmode.width() - pWidth.get(0)) / 2,
                (vidmode.height() - pHeight.get(0)) / 2
            );
        } // the stack frame is popped automatically

        // Make the OpenGL context current
        glfwMakeContextCurrent(window);

        // Enable v-sync
        glfwSwapInterval(1);

        // Make the window visible
        glfwShowWindow(window);
    }

    private void loop() {
        // This line is critical for LWJGL's interoperation with GLFW's
        // OpenGL context, or any context that is managed externally.
        // LWJGL detects the context that is current in the current thread,
        // creates the GLCapabilities instance and makes the OpenGL
        // bindings available for use.
         GL.createCapabilities();

        // Set the clear color
        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);

        double lastTime = glfwGetTime();
        double delta;

        // Run the game loop
        while (running) {
            delta = glfwGetTime() - lastTime;
            lastTime = glfwGetTime();

            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // clear the framebuffer

            // Update game state
            update(delta);

            // Render the scene
            render();

            glfwSwapBuffers(window); // swap the color buffers

            // Poll for window events. The key callback above will only be
            // invoked during this call.
            glfwPollEvents();
        }
    }

    /* It's important to note that this is a basic example of the game loop, you will have to add your own game logic, input handling, and rendering code to make a full game or application.

    You can also add some function like "update(double delta)" and "render()" for updating game state and rendering the scene. */