重新绘制球动画的速度不一致

Question

我不确定我是否可能在EDT上推迟某些事情，或者我是否在滥用某种方法。 如果我将swingtimer的延迟增加到0以上，它就会变慢，但是我没有办法让它变得更快。

    import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.geom.Ellipse2D;

import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JFrame;
import javax.swing.SwingWorker;
import javax.swing.Timer;

/*
 * Name: Owen Rosini Date: May 24, 2016 Program Name: SnakeBrickBreaker.java Description:
 */

@SuppressWarnings("serial")
public class SnakeBrickBreaker extends JFrame implements MouseListener {

  private int mouseX, mouseY, pathStartX;
  private Rectangle scoreBox = new Rectangle(0, 0, getWidth(), 150);
  private int level = 5;
  private Ball[] ballList = new Ball[level];
  private boolean playing;
  private int offset;
  private int ballCount = 0;


  public SnakeBrickBreaker() {
    super("Snake Brick Breaker");

    level = 5;
    pathStartX = 250 - 20 / 2;

    Color backgroundColor = new Color(255, 255, 255);
    this.setBackground(backgroundColor);

    Timer timer = new Timer(50, update);

    timer.start();

    addMouseListener(this);

  }

  @Override
  public void mouseClicked(MouseEvent arg0) {

  }

  @Override
  public void mouseEntered(MouseEvent arg0) {}

  @Override
  public void mouseExited(MouseEvent arg0) {}

  @Override
  public void mousePressed(MouseEvent arg0) {

  }

  @Override
  public void mouseReleased(MouseEvent arg0) {
    mouseX = arg0.getX();
    mouseY = arg0.getY();

    offset = 0;

    playing = true;

    addBalls.execute();
  }

  private SwingWorker<Void, Void> addBalls = new SwingWorker<Void, Void>() {
    @Override
    protected Void doInBackground() throws Exception {
      while (ballCount < level) {
        System.out.println("You made it!");

        Ellipse2D.Double ball = new Ellipse2D.Double(pathStartX + offset, getHeight() - 20, 20, 20);

        Ball b = new Ball(ball, ballCount);

        b.determineDx(mouseX, mouseY);
        b.determineDy(mouseX, mouseY);

        System.out.println(ballCount);

        ballList[ballCount] = b;
        ballCount++;

        System.out.println("Done!");

        offset += 50;
      }
      return null;
    }

    @Override
    protected void done() {
      System.out.println("Done adding balls!");
    }
  };

  // *********************************
  // BEGINNING OF SELF-CREATED METHODS
  // *********************************
  Action update = new AbstractAction() {
    public void actionPerformed(ActionEvent e) {
      for (Ball b : ballList) {
        if (b != null && playing == true) {
          b.translate();
          repaint();

        }
        if (ballList[0] != null && ballList[0].getDoneMoving()) {
          pathStartX = ballList[0].getPathEndX();
        }

      }
    }
  };

  public void paint(Graphics g) {
    super.paint(g);
    Graphics2D g2 = (Graphics2D) g;

    g2.setColor(new Color(255, 100, 0));
    g2.setFont(new Font("Arial", Font.PLAIN, 10));
    g2.draw(scoreBox);

    g2.fillRect((int) scoreBox.getX(), (int) scoreBox.getY(), (int) scoreBox.getWidth(),
        (int) scoreBox.getHeight());
    g2.drawString("Score: " + level, 10, 50);

    for (Ball ball : ballList) {
      if (ball != null) {
        g2.fill(ball.getEllipse2D());
      }
    }
  }
}
import java.awt.Rectangle;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Ellipse2D.Double;

Class Ball 
{
   private int x,y, num, pathEndX;
   double dy, dx;
   private Ellipse2D.Double ball;
   private boolean active, doneMoving;

   private static final int WIDTH = 500;
   private static final int HEIGHT = 700;
   private static final int TOP_BAR = 150;

   public Ball(Double double1, int n)
   {
      ball = double1;
      dx = 1;
      dy = 1;
      active = false;
      num = n;
   }

   public int getBottom()
   {
      return (int) (ball.getY() + ball.getHeight());
   }

   public int getTop()
   {
      return (int) (ball.getY());
   }

   public int getLeft()
   {
      return (int) (ball.getX());
   }

   public int getRight()
   {
      return (int) (ball.getX() + ball.getWidth());
   }

   public Ellipse2D.Double getEllipse2D()
   {
      return ball;
   }

   public void determineDx(double xFinal, double yFinal)
   {  
      if(ball.getX() < xFinal)
      {
         dx = 1;
      }

      if(ball.getX() > xFinal)
      {
         dx = -1;
      }
   }

   public void determineDy(double xFinal, double yFinal)
   {
      double a = ball.getX() - xFinal;
      double b = ball.getY() - yFinal;

      dy = (dx*b)/a;
   }

   public double getDx()
   {
      return dx;
   }

   public double getDy()
   {
      return dy;
   }

   public void changeX(double xChange)
   {
      ball.x += xChange;
   }

   public void changeY(double yChange)
   {
      ball.y += yChange;
   }

   public void translate()
   {        
      doneMoving = false;

      if(ball.getX() <= 0 || ball.getX() >= WIDTH - ball.getWidth())
      {
         dx = -dx;
      }

      if(dx == -1)
      {
         if(ball.getX() >= 0)
         {
            ball.x = ball.getX() + dx;
            ball.y = ball.getY() + dy;
         }
      }    
      else if(dx == 1)
      {
         if(ball.getX() <= WIDTH - ball.getWidth())
         {
            ball.x = ball.getX() + dx;
            ball.y = ball.getY() + dy;
         }
      }  

      if(ball.getY() <= TOP_BAR)
      {
         dy = -dy;
      }

      if(ball.getY() > HEIGHT - ball.getHeight() + 5)
      {
         dy = 0;
         dx = 0;
         ball.y = HEIGHT - ball.getHeight();
         pathEndX = (int) ball.x;
         doneMoving = true;
      }  
   }

   public boolean getDoneMoving()
   {
      return doneMoving;
   }

   public int getPathEndX()
   {
      return pathEndX;
   }

}



import java.awt.Rectangle;
import java.awt.geom.Ellipse2D;



public class Brick
{
   private int x,y, count;
   private Rectangle brick;


   public Brick(Rectangle b, int c)
   {
      brick = b;
      count = c;
   }

   public int getBottom()
   {
      return (int) (brick.getY() + brick.getHeight());
   }

   public int getTop()
   {
      return (int) (brick.getY());
   }

   public int getLeft()
   {
      return (int) (brick.getX());
   }

   public int getRight()
   {
      return (int) (brick.getX() + brick.getWidth());
   }

   public int getCount()
   {
      return count;
   }

   public void decreaseCount()
   {
      count--;
   }
}



public class SnakeBrickBreakerRunner
{
   public static void main(String[] args)
   {
      JFrame game = new SnakeBrickBreaker();
      game.setSize(500, 700);
      game.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      game.setLocationRelativeTo(null);
      game.setVisible(true);
   }