使图像在java中沿着一条线移动

Question

我试图制作一个简单的程序，然后单击并显示图像，并沿着从起点到我点击的点的线移动。我似乎无法让图像沿着这条线移动，因为我遇到了斜坡问题。此外，我似乎无法以动画的方式让图片向前移动。有什么建议吗？ （我排除了我的mousemotionlistener代码）

      public class Screen extends JPanel implements Runnable {

      public Thread thread = new Thread(this); //this is needed for a game loop  (i               think)
      public static JLabel statusbar; //displays a status bar showing what mouse       movements are taking place

      private Image cat;  //image of the cat

      public int xCoord; //get the coordinates of the mouse pressed
      public int yCoord;

      public double xCoord2; //get the coordinates as the mouse is released
      public double yCoord2;

      public int yCoordMove;
      public int xCoordMove;

      public double slope;

       public Screen(Frame frame) {
        thread.start();
        loadPic(); //calls the loadPic method above
     Handlerclass handler = new Handlerclass(); //creates a new class to use the mouse   motion listener
     System.out.println("this mouse thing works!");
     addMouseListener(handler);
     addMouseMotionListener(handler);
     statusbar = new JLabel("default");
        add(statusbar);
}
public void run(){ //this is the game run loop
    System.out.println("this is running");
        try{
        Thread.sleep(5); //sleeps the run loop after 5000 game seconds
    } catch(Exception e) {}
}
public void loadPic(){ //loads the picture
    cat = new ImageIcon("C:\\Users\\Camtronius\\Documents\\NetBeansProjects\\Moving Block Proj\\src\\MovingBlock\\catIcon1.png").getImage(); //gets the image
    System.out.println("Image Loaded!");
}
@Override public void paintComponent(Graphics g){
    super.paintComponent(g); //paints the component, the picture, on top

    g.drawImage(cat, xCoord, yCoord, this); //draws the image and at a specific location
    g.drawString("sup tho!", 250, 250); //draws the text to the screen

    g.setColor(Color.black); //sets color to red
    g.drawLine(xCoord, yCoord, xCoordMove, yCoordMove); //draws the clicked line

}
public void picMove(){
    double numerator = yCoord2 - yCoord;
    double denominator = xCoord2 - xCoord;

        if(denominator == 0) {
            denominator =.0001;
        }
    slope = (numerator/denominator);
    System.out.printf("the slope is: %.2f \n\n   ",slope);    

}

Answer 1

   double a=Math.atan2(numerator, denominator);

    double rate=100;   //rate at which block will move
    xCoord=(int) (xCoord + rate* Math.cos(a));
    yCoord=(int) (yCoord + rate* Math.sin(a));

结果：