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[Martin Baeker <>]

Hi Andre,

I just faced the same problem today, Here are a few possibilities to
sweep over a Nef_polyhedron. Hope this helps,

Martin.




  for(Nef_polyhedron::Halffacet_const_iterator
        f = Cube.halffacets_begin (),
        end = Cube.halffacets_end();
      f != end; ++f)
  {
   if(f->is_twin()) continue;
    std::cout << "Outer iteration, next f \n";
    for(Nef_polyhedron::Halffacet_cycle_const_iterator 
          fc = f->facet_cycles_begin(),
          end = f->facet_cycles_end();
        fc != end; ++fc)
      {
        std::cout << "Inner iteration, next fc \n";
        if ( fc.is_shalfedge() )
          {
            std::cout << "Halfedge consists of points \n";
            
            Nef_polyhedron::SHalfedge_const_handle h = fc;
            Nef_polyhedron::SHalfedge_around_facet_const_circulator hc(h), 
he(hc);
            CGAL_For_all(hc,he)
              { // all vertex coordinates in facet cycle
                Nef_polyhedron::SVertex_const_handle v = hc->source();
                const Nef_polyhedron::Point_3& point = v->source()->point();
                std::cout << "p: " << CGAL::to_double(point.x()) << " " <<
                    CGAL::to_double(point.y()) << " " <<
                    CGAL::to_double(point.z()) << std::endl;

              }
            
          }    
      }
    
  }

  // Alternative to iterating over halfedges:
//   Nef_polyhedron::Halfedge_const_iterator  e = Cube.halfedges_begin();
//   CGAL_forall_halfedges(e,Cube) {
  
  
  for(Nef_polyhedron::Halfedge_const_iterator 
        e = Cube.halfedges_begin(),
        end = Cube.halfedges_end();
      e != end; ++e)
  {
    const Nef_polyhedron::Vertex_const_handle& s = e->source();
    const Nef_polyhedron::Vertex_const_handle& t = e->twin()->source();
    const Nef_polyhedron::Point_3& a = s->point();
    const Nef_polyhedron::Point_3& b = t->point();
    std::cout << "From a: " << CGAL::to_double(a.x()) << " " <<
      CGAL::to_double(a.y()) << " " <<
      CGAL::to_double(a.z()) << " to b: " <<
      CGAL::to_double(b.x()) << " " <<
      CGAL::to_double(b.y()) << " " <<
      CGAL::to_double(b.z()) <<std::endl;
    typedef Nef_polyhedron::Object_handle Object_handle;
    typedef Nef_polyhedron::Vertex_const_handle Vertex_const_handle;
    Vertex_const_handle v;
    Object_handle o = Cube.locate(a);
    if(CGAL::assign(v,o))
      std::cout << " a is a vertex" << std::endl;
    else
      std::cout << " a is not a vertex" << std::endl;
  }

//   Nef_polyhedron::Vertex_const_iterator v;
  
//     CGAL_forall_vertices(v, Cube.sncp())
  for(Nef_polyhedron::Vertex_const_iterator 
        v = Cube.vertices_begin(),
        end = Cube.vertices_end();
      v != end; ++v)
    {
    const Nef_polyhedron::Point_3& a = v->point();
    std::cout << "Vertex: " << CGAL::to_double(a.x()) << " " <<
      CGAL::to_double(a.y()) << " " <<
      CGAL::to_double(a.z()) << std::endl;
      
    }
  

> Hi!
> 
> I am looking for an way to iterate over all facets, which belong to a 
> bounded
> volume of a Nef_polyhedron_3. ATM I am kind of overwhelmed by the
> documentation, so I am guess it's possible, but I don't see an easy way to
> accomplish this. Maybe there is somebody who give me quick hint which kind 
> of
> iterator (combination?) I could employ??
> 
> Kind regards,
> Andre Massing
> 
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