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[costantinos <>]

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" ;



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