1 package demo; 2 3 /** 4 * Java 碰撞的球 MovingBall (整理) 5 * 声明： 6 * 这份源代码没有注释，已经忘记了为什么要写他了，基本上应该是因为当时觉得好玩吧。 7 * 有时候想想，也许是因为当时就是想做一个这样的效果的东西。 8 * 9 * 2016-1-2 深圳 南山平山村 曾剑锋 10 */ 11 12 import java.awt.Color; 13 import java.awt.Graphics; 14 15 import javax.swing.JFrame; 16 import javax.swing.JPanel; 17 18 public class MovingBall extends JPanel { 19 20 private static final long serialVersionUID = 1L; 21 static int centerX = 600/2; 22 static int centerY = 600/2; 23 final Ball ball = new Ball(centerX, centerY); 24 boolean cicleflag = true; 25 int cicleSemi = 0; 26 double angle = 0; 27 int ballCicle = 30; 28 public MovingBall() { 29 start(); 30 } 31 @Override 32 public void paint(Graphics graphics) { 33 super.paint(graphics); 34 this.setBackground(Color.black); 35 graphics.setColor(Color.BLUE); 36 graphics.fillArc(centerX-cicleSemi/2, centerY-cicleSemi/2, cicleSemi, cicleSemi, 0, 360); 37 ball.drawing(graphics); 38 graphics.setColor(Color.white); 39 graphics.drawArc(centerX-cicleSemi/2, centerY-cicleSemi/2, cicleSemi, cicleSemi, 0, 360); 40 graphics.fillArc((int)(centerX+cicleSemi/2*Math.cos(angle*Math.PI/180)-ballCicle/2), (int)(centerY+cicleSemi/2*Math.sin(angle*Math.PI/180)-ballCicle/2), ballCicle, ballCicle, 0, 360); 41 graphics.fillArc((int)(centerX+cicleSemi/2*Math.cos((angle+180)*Math.PI/180)-ballCicle/2), (int)(centerY+cicleSemi/2*Math.sin((angle+180)*Math.PI/180)-ballCicle/2), ballCicle, ballCicle, 0, 360); 42 } 43 public void start() { 44 new Thread(new Runnable() { 45 46 @Override 47 public void run() { 48 while (true) { 49 try { 50 ballMove(ball); 51 52 if (cicleflag == true) { 53 cicleSemi += 2; 54 if (cicleSemi > centerX) { 55 cicleflag = false; 56 } 57 }else { 58 cicleSemi -= 2; 59 if (cicleSemi < 0) { 60 cicleflag = true; 61 } 62 } 63 angle ++; 64 repaint(); 65 Thread.sleep(20); 66 } catch (InterruptedException e) { 67 e.printStackTrace(); 68 } 69 } 70 71 } 72 73 public void ballMove(Ball ball) { 74 ball.x += ball.dx; 75 ball.y += ball.dy; 76 if (ball.x < 50 || ball.x > centerX*2-50) { 77 ball.dx = -ball.dx; 78 }else if (ball.y < 50 || ball.y > centerY*2-50) { 79 ball.dy = -ball.dy; 80 } 81 } 82 }).start(); 83 } 84 85 public static void main(String[] args) { 86 JFrame jFrame = new JFrame(); 87 jFrame.setTitle("MovingBall"); 88 jFrame.setSize(centerX*2, centerY*2); 89 jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 90 jFrame.setLocationRelativeTo(null); 91 92 MovingBall moveBall = new MovingBall(); 93 jFrame.add(moveBall); 94 jFrame.setVisible(true); 95 } 96 } 97 98 class Ball{ 99 static int step = 10; 100 int x; 101 int y; 102 int dx; 103 int dy; 104 double angle; 105 int cicle = 30; 106 public Ball(int x, int y) { 107 this.x = x; 108 this.y = y; 109 this.angle = Math.random()*360; 110 if (angle <= 180) { 111 dx = (int) (step*Math.cos(angle*Math.PI/180)); 112 dy = (int) (step*Math.sin(angle*Math.PI/180)); 113 }else { 114 dx = (int) (step*Math.cos(angle*Math.PI/180)); 115 dy = -(int) (step*Math.sin(angle*Math.PI/180)); 116 } 117 } 118 public Ball(int x, int y, int angle) { 119 this.x = x; 120 this.y = y; 121 this.angle = angle; 122 if (angle <= 180) { 123 dx = (int) (step*Math.cos(angle*Math.PI/180)); 124 dy = (int) (step*Math.sin(angle*Math.PI/180)); 125 }else { 126 dx = (int) (step*Math.cos(angle*Math.PI/180)); 127 dy = -(int) (step*Math.sin(angle*Math.PI/180)); 128 }; 129 } 130 public void drawing(Graphics graphics) { 131 graphics.setColor(Color.white); 132 graphics.fillArc(this.x-cicle/2, this.y-cicle/2, cicle, cicle, 0, 360); 133 } 134 }
效果如图：
