text: #ifndef _GL_RENDER_EDGES_
  #define _GL_RENDER_EDGES_
  
  #include <CGAL/gl.h>
  
  template <class Polyhedron>
  void gl_render_edges(Polyhedron& polyhedron)
  {
    typedef typename Polyhedron::Traits Kernel;
    typedef typename Kernel::Point_3 Point;
  
    ::glBegin(GL_LINES);
    typename Polyhedron::Edge_iterator he;
    for(he = polyhedron.edges_begin();
        he != polyhedron.edges_end();
        he++)
    {
      const Point& a = he->vertex()->point();
      const Point& b = he->opposite()->vertex()->point();
      ::glVertex3d(a.x(),a.y(),a.z());
      ::glVertex3d(b.x(),b.y(),b.z());
    }
    ::glEnd();
  } 
  
  #endif // _GL_RENDER_EDGES_
  
  
  
  
  