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[Matthias Teich <>]

Hi again!

I need your help once again :(
I am trying to store normals in the vertices of a polyhedron_3, so I 
have written the following Items class:


#include <CGAL/Polyhedron_3.h>
#include <CGAL/HalfedgeDS_vertex_base.h>
#include <CGAL/HalfedgeDS_halfedge_base.h>
#include <CGAL/HalfedgeDS_face_base.h>

struct MyPolyhedronItems{
   template < class Refs, class Traits>
   struct Vertex_wrapper{
       typedef typename Traits::Vector_3 Normal;
       typedef typename Traits::Point_3 Point;
       typedef CGAL::HalfedgeDS_vertex_base< Refs, CGAL::Tag_true, 
Point> Vertex;
   };
   template < class Refs, class Traits>
   struct Halfedge_wrapper {
       typedef CGAL::HalfedgeDS_halfedge_base< Refs>                
Halfedge;
   };
   template < class Refs, class Traits>
   struct Face_wrapper {
       typedef typename Traits::Plane_3 Plane;
       typedef CGAL::HalfedgeDS_face_base< Refs, CGAL::Tag_true, 
Plane>   Face;
   };
};


My Polyhedron is defined as
typedef CGAL::Simple_cartesian<double> Kernel;
typedef CGAL::Polyhedron_3<Kernel, MyPolyhedronItems> Polyhedron;

Everything seems to be fine, but I cant access the normals.

This is how I tried:
Vertex_iterator cv_it = polyhedron.vertices_begin();
Vector_3 n = cv_it->Normal;

Can anyone please tell me how to access them? It cannot be too hard I 
guess, but I dont get it.

Best regards,
Matthias