public MyCircle(MyCircle circle)
 {
     center         = circle.Center;
     radius         = circle.Radius;
     belongPlane    = circle.BelongPlane;
     circlePoints3d = circle.CirclePoints;
     ComputeArea();
     neighbors = circle.Neighbors;
 }
 public void AddNeighbor(MyCircle c)
 {
     neighbors.Add(c);
 }
 public void AddCircle(MyCircle c)
 {
     circleList.Add(c);
 }
 public MyGCylinder(MyCircle c)
 {
     circleList.Add(c);
 }