82.游戏项目-椭圆轨迹的实现

package test;

import java.awt.Frame;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class MyFrame extends Frame {
    
    public void launchFrame(){
        setSize(Constant.GAME_WIDTH,Constant.GAME_HEIGHT); 
        setLocation(300,150);
        setVisible(true);
        
        new PaintThread().start();
        
        addWindowListener(new WindowAdapter(){
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }    
        });
    }
    
    class PaintThread extends Thread{
        public void run(){
            while(true){
                repaint();
                try {
                    Thread.sleep(40);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    }

}

--------------继承 MyFrame的类 减少代码量

package test;
import java.awt.Color;
import java.awt.Font;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
/**
 * 椭圆轨迹的实现
 * @author Nicholas
 * 
 */
public class GameFrame4 extends MyFrame {
    
    Image img = GameUtil.getImage("picture/test3.jpg");
    
    private double x = 100, y = 100;
    private double degree = 3.14/3;// [0,2pi];
    
    public void paint(Graphics g) {
        g.drawImage(img, (int)x, (int)y, null);
        x = 250 + 100* Math.cos(degree);
        y = 200 + 50* Math.sin(degree);
        degree += 0.1;
    }
    
    public static void main(String[] args) {
        GameFrame4 gf=new GameFrame4();
        gf.launchFrame();
    }    
}

补：

经常用到的常量可以用一个类封装存储起来

package test;
/**
 * 游戏项目中用到的常量
 * @author Nicholas
 *
 */
public class Constant {
    
    public static final int GAME_WIDTH=500;
    public static final int GAME_HEIGHT=500;
    
}