[Java 游戏编程]游戏框架预览

来源：互联网发布：贾利尔.奥卡福数据编辑：程序博客网时间：2024/05/19 15:41

游戏窗体：
JFrame 容器加载一个游戏画布实现【add(GamePanel)】

pack()方法表示由JComponent来决定窗体大小

import javax.swing.JFrame;public class Game {public static void main(String []args) {JFrame window = new JFrame("First Game");window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);window.add(new GamePanel());window.pack();window.setVisible(true);}}

游戏画布：
构造函数中

/*实现GUI event的处理*/
setFocusable(true); 设置GamePanel成为控件焦点
requestFocus(); 请求获取焦点

游戏线程的创建：
addNotify(); 方法在JFrame加载了GamePanel后执行因为方便开始游戏线程所以重写了该方法该方法一定要先执行super.addNotify 父类方法然后在执行游戏线程等

双缓冲：

private BufferedImage image; // 后备缓冲【back-buffer 是一个与屏幕大小一样的虚拟屏幕】与屏幕互相切换平滑的实现游戏中动态效果
private Graphics2D g; // 游戏画刷用于把图像画到image中

gameRender(); // 渲染到后备缓冲【具体细节参照实现】

gameDraw(); // 将后备缓冲绘制到屏幕上【具体细节参照实现】

计算fps：

一般游戏为30fps
startTime = System.nanoTime(); 获取当前时间【单位纳秒】
URDTime = (System.nanoTime - startTime) / 1000000; 求出当前循环中的游戏逻辑使用时间【单位微秒】
waitTime = targetTime - URDTimeMillis; 求出fps【单位微秒】

import javax.swing.*;import java.awt.*;import java.awt.image.*;public class GamePanel extends JPanel implements Runnable  {private static final int WIDTH = 400;private static final int HEIGHT = 400;private Thread thread;private boolean running;private BufferedImage image;// game canvasprivate Graphics2D g; // game paint brushprivate int FPS = 30;private double averageFPS;public GamePanel() {setPreferredSize(new Dimension(WIDTH, HEIGHT));setFocusable(true);requestFocus();}// FUNCTIONSpublic void addNotify() {super.addNotify();if (thread == null) {thread = new Thread(this);thread.start();}// other game thread stuff}private void gameStart() {running = true;}public void run() {gameStart();image = new BufferedImage (WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);g = (Graphics2D) image.getGraphics();long startTime;long URDTimeMillis;long waitTime;long totalTime = 0;int frameCount = 0;int maxFrameCount = 30;long targetTime = 1000 / FPS;// GAME LOOPwhile (running) {startTime = System.nanoTime();gameUpdate();gameRender();gameDraw();URDTimeMillis = (System.nanoTime() - startTime) / 1000000;waitTime = targetTime - URDTimeMillis;try {Thread.sleep(waitTime);}catch (Exception e) { } totalTime += System.nanoTime() - startTime;frameCount++;if (frameCount == maxFrameCount) {averageFPS = 1000.0 / ((totalTime / frameCount) / 1000000);frameCount = 0;totalTime = 0;}}}private void gameUpdate() {}private void gameRender() {// draw to screen image firstg.setColor(Color.WHITE);g.fillRect(0, 0, WIDTH, HEIGHT);g.setColor(Color.BLACK);g.drawString("FPS: " + averageFPS, WIDTH / 2, HEIGHT / 2);}private void gameDraw() {// draw to game screen image secondGraphics g2 = this.getGraphics();g2.drawImage(image, 0 , 0, null);g2.dispose();}}

0 0