>Maybe you should update the screen in steps to make it smooth
>
>

>for( x = oldPosition; x <= newPosition; x += 0.5 ) // degrees  ( or less than 0.5)
>   updateScreen();
>

Hmm. The events come in fast enough - in fact, as in previous reply, I'm taking the opposite approach to *reduce* the number of screen updates (which draws an arrow on HTML5 Canvas)