Hi

I'm trying to figure out how to make an animation move smoothly.. so i've
been looking around.. i've found 3 other methods besides just using sleep()
at each frame.. i've tried implementing these methods but i cant see much of
a difference.. but which of the following, if any, is the best way to go
about it.. or is there a better way..

method 1: the nono
..
while(true){
   x++; //some simple movement
   y++;
   paint(getGraphics());
   try{
       Thread.currentThread().sleep(delay);
   }
   catch(Exception e){}
}

method 2:
...
while(true){
   long start = System.currentTimeMillis();
   x++; //some simple movement
   y++;
   paint(getGraphics());
   try {
       Thread.sleep(Math.max(0, (start + delay) -
System.currentTimeMillis()));
   }
   catch (InterruptedException e) {};
}

method 3:
...
while(true){
   long start = System.currentTimeMillis();
   x++; //some simple movement
   y++;
   paint(getGraphics());
   long sleepTime = delay - (System.currentTimeMillis() - start);
   if (sleepTime > 0)
   try{
       Thread.currentThread().sleep(sleepTime);
   }
   catch(Exception e){}
}

method 4: frame independent

int velocity = 500;
long end_time = 0;
long start_time = System.currentTimeMillis();
float elapsed_time = 0;
float dtime = 0;
while(true){
     end_time = System.currentTimeMillis();
     elapsed_time =   end_time - start_time ;
     dtime = elapsed_time / 1000  ;
     x += dtime * velocity; //some simple movement
     y += dtime * velocity;
     start_time = System.currentTimeMillis();
     paint(getGraphics());
     try{
         Thread.currentThread().sleep(delay);
     }
     catch(Exception e){}
}

thanx
mike