public VertexEv(Vector3 vertex, int e1, int e2, vType typ)       // intersection point
 {
     v     = vertex;
     edge  = e1;
     edge2 = e2;
     type  = typ;
 }
 public VertexEv(IntersectionPoint I)
 {
     v     = I.P;
     edge  = I.Edge1;
     edge2 = I.Edge2;
     type  = vType.INTERSECT;
 }
 public VertexEv(Vector3 vertex, int edg, vType typ)       // segment end
 {
     v    = vertex;
     edge = edg;
     type = typ;
 }