public int AngleOfPoint(Point point)
 {
     return((int)System.Math.Truncate(CircleF.AngleOfPoint(CircleF.FromCircle(this), new PointF((float)point.X, (float)point.Y))));
 }
 public int AreaOfIntersect(Circle cir)
 {
     return((int)System.Math.Truncate(CircleF.AreaOfIntersect(CircleF.FromCircle(this), CircleF.FromCircle(cir))));
 }
 public Point GetPointAtAngle(float degree)
 {
     return(Point.Truncate(CircleF.PointAtAngle(CircleF.FromCircle(this), degree)));
 }