CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

The following compiles on my machine.

Sebastien.

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Polyhedron_3.h>
#include <CGAL/convex_hull_3.h>
#include <CGAL/Polyhedron_items_with_id_3.h>

typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
typedef CGAL::Polyhedron_3<K,CGAL::Polyhedron_items_with_id_3> Polyhedron;

int main()
{
  std::vector<K::Point_3> points;
  Polyhedron P;

  CGAL::convex_hull_3(points.begin(),points.end(),P);

}



On 09/06/2012 11:54 AM, Mathieu Westphal wrote:
> On 09/05/2012 07:07 AM, Sebastien Loriot (GeometryFactory) wrote:
> > On 09/04/2012 05:24 PM, Mathieu Westphal wrote:
> > > I have a polyhedron_3 (with only triangles in it ) and i want to create
> > > a vtkPolyData with it.
> > >
> > > I can extract Points from the polyhedron without problem and inject them
> > > into the vtkPolyData
> > >
> > > However i see no evident way to extract cells (facets in CGAL?)
> > Looking at this page:
> > http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Polyhedron_ref/Class_Polyhedron_3.htm
> >
> >
> > given a polyhefron Pyou can see that the range
> > P.facets_begin(), P.facets_end() is what you are looking for.
> >
> > To access the vertices, given a facet f,
> >
> > Halfedge_handle h=f.halhedge()
> > do{
> > h->vertex();//access the vertex
> > h->vertex()->point();//access the point
> > h=h->next();
> > }while (h!=f.halhedge());
> >
> > To associate an id to each vertex you can use a
> > std::map<Vertex_handle,unsigned> for example
> Thanks, everything works well, thanks to you !
> > or use an
> > item class with id likeClass_Polyhedron_items_with_id_3
> >
> > http://www.cgal.org/Manual/latest/doc_html/cgal_manual/BGL_ref/Class_Polyhedron_items_with_id_3.html
> The mesh generation fonction (CGAL::convex_hull_3) seem not to work with
> a Polyhedron_items_with_id_3
> > Sebastien.
> >
> > > vtkPolyData need for each cell, the id of constituing points.
> > >
> > > Is there any way to find facets from one points? or points from one
> > > facet?