private boolean isAngleAtBack(double angle){
  return (Math.sin(Math.toRadians(angle)) > 0.0);
}

private boolean isAngleAtBack ( double angle ) { return ( Math . sin ( Math . toRadians ( angle ) ) > 0.0 ) ; }
a utility method that returns true if the angle represents a point at the back of the 3d pie chart . 0 - 180 degrees is the back , 180 - 360 is the front .
