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

public class Kommunikation extends Applet implements Runnable {
	private Thread	animatorThread = null;
  private int posX, posY;             // Position
  private int incx=1, incy=1;         // Richtungszuwachs
  private int rad = 20;

  private Image offScreenBuffer;      //
  private Graphics offScreenGraphics; // Grafik kontext für den offScreenBuffer.

  public void init(){
    offScreenBuffer = this.createImage(size().width , size().height);
    // Wir müssen unser Buffer-Image als Graphics object benutzen:
    offScreenGraphics = offScreenBuffer.getGraphics();

      posX = (int)(size().width/2);
      posY = (int)(rad*2);
      incx = -1;
      incy = -1;
  }

  public void Ballsize(float faktor){
    rad = (int)(rad*faktor);
    if (rad<5) rad=5;
  }

  public void update(Graphics g){
    paint(offScreenGraphics);   // gibt den off-screen buffer und die "paint" Methode,
               // die jetzt genauso auf den Buffer Zeichnet wie sonst auf den Bildschrim

    g.drawImage(offScreenBuffer, 0, 0, this);
               // Jetzt werden die Grafiken auf den grafikkontext vom
               // Browser gezeichnet
  }

	public void paint(Graphics g) {            // Überschreiben der Methode Paint()
   //Graphics2D g2 = (Graphics2D) g;
   //g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);

    g.setColor(Color.black);
    g.fillRect(0,0,size().width, size().height);
    g.setColor(Color.cyan);
    g.create().fillOval(posX-rad-3*incx ,posY-rad-3*incy ,rad*2 ,rad*2 );

    g.setColor(Color.blue);
    g.create().fillOval(posX-rad ,posY-rad ,rad*2 ,rad*2 );
  }

	public void start() {
		if(animatorThread == null) {
			animatorThread = new Thread(this);
 			animatorThread.start();
		}
	}

	public void stop() {
		animatorThread = null;
	}

  public void run() {
   while (Thread.currentThread() == animatorThread){
      posX+= incx;
      posY+= incy;
      if (posX <= rad)              incx =1;
      if (posX >= size().width-rad) incx =-1;
      if (posY <= rad)              incy =1;
      if (posY >= size().height-rad)incy =-1;
      repaint();

      try {
			  Thread.sleep(10);
      }
      catch(InterruptedException e){
	  	  showStatus("Error: " + e.toString());
      }
    }
	}

}