public class TurtleAnimationDemo extends Thread
{
    
    public static void main(String[] args)
    {
        World earth = new World();
        Turtle donatello = new Turtle(10, 240, earth); 
        Turtle michelangelo = new Turtle(100, 240, earth);
  
        forwardSlowly(donatello, 100, 10); 
        forwardSlowly(michelangelo, 100, 1);
    }// end of main
    
    // moves ' pixels' 1 pixel at a time with
    // a 'delay' millisecond delay between each step
    public static void forwardSlowly(Turtle turtle, int distance, int delay)
    {
    	
        for (int i = 0; i < distance; i++)
        {
        	turtle.forward(1);  	
        	try{Thread.sleep(delay);} catch (InterruptedException ex) {}
        }
    
    }// end of forwardSlowly
      
}