CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

Please provide a minimal example showing the problem. I tried it with 
CGAL-4.3-beta1 and CGAL-4.2 on the attached model (in.off). I also 
attach the output (out.off). I set the stop counter to 3000.

Sebastien.


On 10/11/2013 05:20 PM, costantinos wrote:
> Hi,
>
> I am endeavouring to constrain the border edges of a 3D surface when I am
> simplifying the mesh. However, the edges are not maintained in their
> position. Please find an extract from the code below, I have used the
> example provided in the manual and added a little to it. Is it the case that
> below a stopping count threshold the constraint no longer works? I compared
> the results of edges constrained and non-constrained and found that the
> non-constrained was more faithful to the original mesh geometry for the same
> stopping criterion! Any help or advice would be appreciated.
>
> Thank you.
>
>
>      SMS::Count_stop_predicate<Surface>  stop(80);
>
>      Constrains_map constrains_map ;
>
>      surface.normalize_border();
>      if ( surface.size_of_border_edges() != 0) {
>          std::cerr<<  "The input object has the following no of border edges:
> "<<  surface.size_of_border_edges()<<  "\n";
>      }
>
>
>      for( Surface::Halfedge_iterator eb = surface.border_halfedges_begin(),
> ee = surface.halfedges_end() ; eb != ee ; ++ eb )
>      {
>          constrains_map.set_is_constrained(eb,true);
>      }
>
>
>      int r = SMS::edge_collapse
>      (surface
>       ,stop
>
> ,CGAL::vertex_index_map(boost::get(CGAL::vertex_external_index,surface))
>       .edge_index_map  (boost::get(CGAL::edge_external_index  ,surface))
>       .edge_is_border_map(constrains_map)
>       );
>
>      std::cout<<  "\nFinished...\n"<<  r<<  " edges removed.\n"
>      <<  (surface.size_of_halfedges()/2)<<  " final edges.\n" ;
>
>
>
> --
> View this message in context: 
> http://cgal-discuss.949826.n4.nabble.com/Mesh-simplification-with-edges-marked-as-non-removable-tp4658180.html
> Sent from the cgal-discuss mailing list archive at Nabble.com.

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