import java.awt.Panel;        // För ritning
import java.awt.MediaTracker; // Invänta bild
import java.awt.Image;        // Bild
import java.awt.Graphics;     // Grafik
import java.awt.Toolkit;      // Gfkspecial

public class rocket_c
  extends Panel
  implements Runnable
{

  public rocket_c()
  {
    this.xpos = -200;
    try
    {
      this.tracker = new MediaTracker( 
        this ); // Component
      this.bild = Toolkit.getDefaultToolkit().getImage(
        ( "rocket.gif") ); // File or URL
      this.tracker.addImage( 
        this.bild,  // Image 
        0 );        // ID-num
    }

    catch ( Exception exc )
    {
      System.out.println( "Fel på ROCKET-datan" );
    }
  } // rocket_c


  public void start()
  {
    this.keep_running = true;
    Thread rocket_thread = new Thread( 
      this ); // Runnable object
    rocket_thread.start();
  } // start


  public void run()
  {
    try 
    {
      tracker.waitForID(0); // ID-num
      this.width = bild.getWidth( 
        this ); // ImageObserver
      this.height = bild.getHeight( 
        this ); // ImageObserver
      this.xpos = -this.width;
      this.xstep = 3;

//      this.xlast = super.getWidth(); // JDK 1.2
      this.xlast = super.getBounds().width;
    } 
    catch (InterruptedException e) 
    {
      return;
    //////////
    }

    while ( this.keep_running )
    {
      try
      {
        Thread.sleep( 
          20 ); // Milliseconds
      }
      catch ( InterruptedException exc )
      {
      }

      this.rubx = this.xpos;
      this.xpos = this.xpos + this.xstep;
      if ( this.xpos > this.xlast )
      {
        this.xpos = -this.width;
      }
      super.repaint();
    }
  } // run


  public void update( Graphics gr )
  {
    gr.clearRect( 
      this.rubx,       // x 
      20,              // y
      this.xstep,      // width
      this.height );   // height
    this.paint( gr );
  } // update

  public void paint( Graphics gr )
  {
    if ( this.keep_running )
    {
      gr.drawImage(  
        this.bild,            // Image
        this.xpos,            // x
        20,                   // y
        this );               // ImageObserver
    }
  } // paint

  private Image bild;
  private int xpos, rubx, xstep, xlast, height, width;
  private boolean keep_running;
  private MediaTracker tracker;
} // rocket_c