我正在做彈跳球問題,我給出了這個公式:(velocity)vx = v0 * cos(angle)。和(x位置)x = v0 * cos(角度)* t。但是,我無法讓球正常彈跳。 問題是,當球擊中右側垂直牆後,它會在窗口右側的某個範圍內開始反彈。 (y和vy在這種情況下應該沒有關係)。 我該如何解決這個奇怪的彈跳問題,使其在x方向上反彈屬性?Java彈跳球
public class GamePanel2 extends JPanel implements KeyListener, ActionListener{
Timer tm = new Timer(60, this); //this refers to the ActionListener
public int score = 0;
public GamePanel2(){
addKeyListener(this);
setFocusable(true);
setBackground(Color.BLACK);
}
public int getScore() {
return score;
}
public double v0 = 100;
public double t = 0;
public double angle = Math.PI/2.5;
public double x = 0;
public double y = 0;
public double vx =0;
public double vy = 0;
public int move = 0;
public int paddlex =0;
public void paintComponent(Graphics g){
int h = getHeight();
int w = getWidth();
vx = v0*Math.cos(angle);
vy = v0*Math.sin(angle);
Graphics2D g2d = (Graphics2D)g;
g2d.translate(0.0,h);
g2d.scale(1.0, -1.0);
//ball
g2d.setColor(Color.GREEN);
g2d.fillOval((int)Math.round(x), (int)Math.round(y+6), 20, 20);
//paddle
g2d.setColor(Color.RED);
g2d.fillRect(paddlex + move, 0, 60, 6);
repaint();
}
//KeyListener methods
@Override
public void keyPressed(KeyEvent arg0) {
if(arg0.getKeyCode() == KeyEvent.VK_SPACE){
tm.start();
}
else if(arg0.getKeyCode()==KeyEvent.VK_ESCAPE){
tm.stop();
}
if(arg0.getKeyCode() == KeyEvent.VK_RIGHT){
move += 30;
}
//if pressed right key
if(arg0.getKeyCode() == KeyEvent.VK_LEFT){
move -= 30;
}
repaint();
}
@Override
public void keyReleased(KeyEvent arg0) {
}
@Override
public void keyTyped(KeyEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
t = 0.2;
vy -= 9.8;
x += vx;
y += (vy)*t-(t*t*9.8)*0.5;
if(x<= 0){
vx = v0*Math.cos(angle);
}
if (x>=getWidth()-20){
vx =-(v0*Math.cos(angle));
}
repaint();
}
}