CGAL users discussion list

["Laurent Rineau (GeometryFactory)" <>]

Le mercredi 07 octobre 2009 16:23:45, Alejandro Aguilar Sierra a écrit :
> Hi Matt,
> 
> Thank you for the hint. Actually what I want is to get the index of
> the vertices on the container so I can build a drawable OBJ file.
> 
> A dirrty way to do it is using this code:
> 
>   for (CDT::Face_iterator fit = cdt.faces_begin(); fit!=
> cdt.faces_end(); ++fit) {
>     int idx = 0;
>     int i0, i1, i2;
> 
>     for (CDT::Vertex_iterator vit = cdt.vertices_begin(); vit!=
> cdt.vertices_end(); ++vit) {
>       idx++;
>       if ((*vit).point() == (*fit).vertex(0)->point())  i0 = idx;
>       if ((*vit).point() == (*fit).vertex(1)->point())  i1 = idx;
>       if ((*vit).point() == (*fit).vertex(2)->point())  i2 = idx;
>     }
> 
>     std::cout << "f " << i0 << " " << cdt.triangle(fit) << std::endl;
>   }
> 
> And I get a drawable mesh. Is there a cleaner way?

Fill a std::map<Vertex_handle,  int>:
  
   std::map<Vertex_handle,  int> vertex_index;
   int idx = 0;
   for (CDT::Vertex_iterator vit = cdt.vertices_begin(); vit!=
        cdt.vertices_end(); ++vit) {
      vertex_index[vit]=idx++;
   }
  

   for (CDT::Face_iterator fit = cdt.faces_begin(); fit!=
         cdt.faces_end(); ++fit) {
     int i0 = vertex_index[fit->vertex(0)];
     int i1 = vertex_index[fit->vertex(1)];
     int i2 = vertex_index[fit->vertex(2)];
     // and so on...
  }


-- 
Laurent Rineau, PhD
Release Manager of the CGAL Project
http://www.cgal.org/
R&D Engineer at GeometryFactory
http://www.geometryfactory.com/