Estoy tratando de hacer que una bola se mueva gradualmente cuando presionas una de las teclas de flecha, en este momento solo se teletransporta. Lo quiero para que puedas verlo moverse. Basado en estoejemploEstoy usando uniones de teclas, y hay una variable llamada delta que hace que la bola se mueva 50 píxeles, pero como dije, la bola solo aparece 50 píxeles en cualquier dirección en la que se presionó la tecla de flecha, quiero que sea como si si fueras a patear una pelota, puedes verla llegar de un punto a b. Vaya a la línea 89 que es donde creo que está el problema.

package game;

import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;

/**
 * @see https://stackoverflow.com/questions/6991648
 * @see https://stackoverflow.com/questions/6887296
 * @see https://stackoverflow.com/questions/5797965
 */
public class LinePanel extends JPanel {
myObject ball;

private Point b1 = new Point(0,0);


private MouseHandler mouseHandler = new MouseHandler();
private Point p1 = new Point(100, 100);
private Point p2 = new Point(540, 380);
private boolean drawing;

public LinePanel() {
    this.setPreferredSize(new Dimension(640, 480));
    this.addMouseListener(mouseHandler);
    this.addMouseMotionListener(mouseHandler);
}

@Override
protected void paintComponent(Graphics g) {
    super.paintComponent(g);
    Graphics2D g2d = (Graphics2D) g;
    g2d.setColor(Color.blue);
    g2d.setRenderingHint(
        RenderingHints.KEY_ANTIALIASING,
        RenderingHints.VALUE_ANTIALIAS_ON);
    g2d.setStroke(new BasicStroke(8,
        BasicStroke.CAP_ROUND, BasicStroke.JOIN_BEVEL));
    g.drawLine(p1.x, p1.y, p2.x, p2.y);
    ball = new myObject(b1.x,b1.y,"Stuff/ball.png",50,50);
    g.drawImage(ball.getImage(),ball.getX(),ball.getY(), ball.getWidth(),         ball.getHeight(), null);
    repaint();
}

private class MouseHandler extends MouseAdapter {

    @Override
    public void mousePressed(MouseEvent e) {
        drawing = true;
        p1 = e.getPoint();
        p2 = p1;
        repaint();
    }

    @Override
    public void mouseReleased(MouseEvent e) {
        drawing = false;
        p2 = e.getPoint();
        repaint();
    }

    @Override
    public void mouseDragged(MouseEvent e) {
        if (drawing) {
            p2 = e.getPoint();
            repaint();
        }
    }
}

private class ControlPanel extends JPanel {

    private static final int DELTA = 50;
// above is telling the ball to move by 50 pixels
    // I want it to move by 50 pixels but gradually I dont want it to teleport
    public ControlPanel() {
        this.add(new MoveButton("\u2190", KeyEvent.VK_LEFT, -DELTA, 0));
        this.add(new MoveButton("\u2191", KeyEvent.VK_UP, 0, -DELTA));
        this.add(new MoveButton("\u2192", KeyEvent.VK_RIGHT, DELTA, 0));
        this.add(new MoveButton("\u2193", KeyEvent.VK_DOWN, 0, DELTA));


    }


    private class MoveButton extends JButton {

        KeyStroke k;
        int myX, myY;

        public MoveButton(String name, int code, final int myX, final int myY) {
            super(name);
            this.k = KeyStroke.getKeyStroke(code, 0);
            this.myX = myX;
            this.myY = myY;
            this.setAction(new AbstractAction(this.getText()) {

                @Override
                public void actionPerformed(ActionEvent e) {
                    LinePanel.this.b1.translate(myX, myY);

                    LinePanel.this.repaint();
                }
            });
            ControlPanel.this.getInputMap(
                WHEN_IN_FOCUSED_WINDOW).put(k, k.toString());
            ControlPanel.this.getActionMap().put(k.toString(), new AbstractAction() {

                @Override
                public void actionPerformed(ActionEvent e) {
                    MoveButton.this.doClick();
                }
            });
        }
    }
}



private void display() {
    JFrame f = new JFrame("LinePanel");
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.add(this);
    f.add(new ControlPanel(), BorderLayout.SOUTH);
    f.pack();
    f.setLocationRelativeTo(null);
    f.setVisible(true);
}

public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {

        @Override
        public void run() {
            new LinePanel().display();
        }
    });
}


}