private function checkLine(line:Sprite):void
    {
     // get the bounding box of the line
     var bounds:Rectangle = line.getBounds(this);
     if(ball.x > bounds.left && ball.x < bounds.right)
     {
      
      // 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;