BouncingBall

//BouncingBall with gravity and 10 second time limit (before stopping).
import acm.program.*;
import acm.graphics.*;
import java.awt.*;

public class BouncingBall extends GraphicsProgram {
    public void run() {
       GOval ball = new GOval(25, 25, 50, 50);
       ball.setFilled(true);
       ball.setFillColor(new Color(255, 0, 0));
       add(ball);
       int frame = 0;
       double dx = 3;
       double dy = -4;
       while(frame < 1000) {
           pause(10);
           if(ball.getX() + ball.getWidth() >= getWidth()
                   || ball.getX() <= 0.0) {
               dx = -dx;
               dx = dx * .8;
           }
           if(ball.getY() + ball.getHeight() >= getHeight()
                   || ball.getY() <= 0.0) {
               dy = -dy;
               dy = dy * .8;
           }
           dy = dy + 0.2;
           ball.move(dx, dy);
           frame = frame + 1;
       }
    }
}