import java.awt.*;
import java.applet.*;

/**
 * Represents a panel that does the painting offscreen  
 * which avoids flickering. Good for using in animations.
 */

class fNoFlickerApplet extends Applet {

    private Image offScreenImage;
    private Graphics offScreenGraphics;
    private Dimension offScreenSize;
    
    public final void update(Graphics theG){

	Dimension d=size();

	if((offScreenImage==null) || 
	   (d.width != offScreenSize.width) || 
	   (d.height != offScreenSize.height)) {
	    
	    offScreenImage = createImage(d.width,d.height);
	    offScreenSize = d;
	    offScreenGraphics = offScreenImage.getGraphics();
	    offScreenGraphics.clearRect(0,
					0,
					offScreenSize.width,
					offScreenSize.height);
	}
	paint(offScreenGraphics);
	theG.drawImage(offScreenImage,0,0,null);
    }
}