private function onEnterFrame(event:Event):void
    {
     line.rotation = (stage.stageWidth/ 2 - mouseX) * .1;
     
     // normal motion code
     ball.vy += gravity;
     ball.x += ball.vx;
     ball.y += ball.vy;
     
     // get angle, sine and cosine
     var angle:Number = line.rotation * Math.PI / 180;
     var cos:Number = Math.cos(angle);
     var sin:Number = Math.sin(angle);
     
     // get position of ball, relative to line
     var x1:Number = ball.x - line.x;
     var y1:Number = ball.y - line.y;
     
     // rotate coordinates
     var y2:Number = cos * y1 - sin * x1;
     
     // perform bounce with rotated values
     if(y2 > -ball.height / 2)
     {
      // rotate coordinates
      var x2:Number = cos * x1 + sin * y1;
      
      // rotate velocity
      var vx1:Number = cos * ball.vx + sin * ball.vy;
      var vy1:Number = cos * ball.vy - sin * ball.vx;
     
      y2 = -ball.height / 2;
      vy1 *= bounce;