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

public class Train extends Applet {
  Shape train=null;

  // For double buffering
  private Image buffer;
  private Graphics buffer_gr;

  public void init() {
    Shape wheels=new Compound(new Circle(10,50,5), new Circle(35,50,5));

    Shape bottom=new Compound(new Compound(wheels,
					   new Line(15,50,30,50)),
			      new Compound(new Line(0,50,5,50),
					   new Line(40,50,45,50)));

    Shape locobt=new Compound(new Compound(bottom,
					   new Line(0,35,45,35)),
			      new Compound(new Line(0,35,0,50),
					   new Line(45,35,45,50)));
    Shape loco=new Compound(locobt,
			    new Compound(new Rectangle(5,20,10,15),
					 new Rectangle(25,15,20,20)));

    Shape car1=new Compound(new Compound(bottom.copy(),
					 new Compound(new Line(0,15,45,15),
						      new Line(-5,45,0,45))),
			    new Compound(new Line(0,15,0,50),
					 new Line(45,15,45,50)));
    car1.move(50,0);
    Shape car2=car1.copy();
    car2.move(50,0);
    train=new Compound(loco,new Compound(car1,car2));
    train.move(105,-10);
   }

  public void paint(Graphics gr) {
    if (buffer == null) {
      buffer = createImage(getSize().width, getSize().height);
      buffer_gr = buffer.getGraphics();
    }
    buffer_gr.setColor(Color.gray);
    buffer_gr.fillRect(0, 0, getSize().width-1, getSize().height-1);

    if(train!=null)
      for (int i = 0; i<30; i=i+1) {
	buffer_gr.setColor(Color.gray);
	train.draw(buffer_gr);
	train.move(-1,0);
	buffer_gr.setColor(Color.black);
	train.draw(buffer_gr);
	gr.drawImage(buffer, 0, 0, this);
	sovSødt(75);
      }
  }

  private void sovSødt(int n) {
    try {
      Thread.sleep(n);
    } catch (InterruptedException e) {}
  }
}