Getting rid of trails?

Java 2D
#1

I know this is all related to double buffering and stuff but I’m trying to use createVolatileImage to draw some stuff on screen, however - there are trails being left behind. I’ve tried to get rid of them by clearing over the background image over the drawing but it doesn’t work.


package _game;

import java.awt.*;
import javax.swing.JFrame;

public class _game extends Canvas implements Runnable {

*/
	private Thread t = new Thread(this);

	private boolean running;
	
	private static int width = 160;
	private static int height = 120;
	private static int scale = 4;
	
	public mouse mouse = new mouse();
	private Screen screen = new Screen();
	
	private long lastTime;
	public static int tick;
	
	public _game(){
		int w = width * scale;
		int h = height * scale;
		
        setPreferredSize(new Dimension(w, h));
        setMaximumSize(new Dimension(w, h));
        setMinimumSize(new Dimension(w, h));
        setBackground(Color.BLACK);   
        
		addMouseListener(mouse);
		addMouseMotionListener(mouse);
		
        this.setFocusable(true);
	}
	
	public void start(){
        lastTime = System.currentTimeMillis();
       
		running = true;
        
		t.start();
	}
	
	public static void main(String[] args){
		_game ga = new _game();
		
		
		
        JFrame frame = new JFrame("derr");
        frame.add(ga);
        frame.pack();
        frame.setResizable(false);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
		
		ga.start();
	}

	public synchronized void stop(){
		running = false;
	}
	
	public void paint(Graphics g)
	{
	}

    public void update(Graphics g)
    {
        render(g);
    }
	
	public void render(Graphics g){

	}

	@Override
	public void run() {
		Image image = null;
		
		while(running){
			tick = ((int)(System.currentTimeMillis() - lastTime)/100);
			
			if(image == null){
				image = createVolatileImage(width * scale, height * scale);
			}
			
			Graphics g = image.getGraphics();
			
			screen.render(g, mouse.mx, mouse.my);
			
			g = getGraphics();
			
			g.drawImage(image, 0, 0, width * scale, height * scale, 0, 0, width * scale, height * scale, null);
			g.dispose();

            try
            {
                Thread.sleep(5);
            }
            catch (InterruptedException e)
            {
            	e.printStackTrace();
            }
		}
	}
	

}

screen.render(g) just draws rectangles at my mouse pos (when it is dragged)

#2

where is g.clearRect(0, 0, width, height); ?

#3

Also it’s best if you use a BufferedImage instead of VolatileImage, since the latter is so unreliable.

#4

I dunno.

Ok, thanks!