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[Sukhraj Singh <>]

Hi Sebastien,

 Instead of getting the segment polyhedron and using that to create an ROI, I directly used the segment_map to create the ROI as follows.

=============================================================================

 for(Polyhedron::Facet_iterator facet_it = (*polyhedron()).facets_begin();

                facet_it != (*polyhedron()).facets_end(); ++facet_it)

        {

            if(segment_property_map[facet_it] == segid)// the particular seg id I want as ROI

            {

                //Let's take the three vertices of facet

                insert_roi_vertex(facet_it->halfedge()->vertex());

                insert_roi_vertex(facet_it->halfedge()->next()->vertex());

                insert_roi_vertex(facet_it->halfedge()->opposite()->vertex());

            }

        }

===============================================================================

I do get a correct ROI as seen form its vizulization, but have a doubt iterating in this way will push same shared vertex among faces again.

I have done this because the Segmentation algo implementation returns a facet based property map.

Thanks to clarify.

On Mon, Sep 5, 2016 at 4:18 PM, Sebastien Loriot (GeometryFactory) <> wrote:

Could you provide a full example reproducing the issue?

Thanks,

Sebastien.

On 09/02/2016 07:24 PM, Sukhraj Singh wrote:

Hello,

I am trying to create a particular segment (which is the output of
surface mesh segmentation) as ROI in Surface Mesh Deformation.

I implemented following code, which is crashing( psb comment below)

==========================================================

void  set_all_vertices_as_roi()

   {

     vertex_iterator  vb,  ve;

     for(boost::tie(vb,  ve)  =  vertices(*polyhedron());  vb  !=  ve;  ++vb)

     {

       insert_roi_vertex(*vb);

     }

   }



//Implement it likewise all mesh vertices as roi


   void  set_segment_vertices_as_roi(Polyhedron  mesh)

   {

     std::size_t  number_of_clusters;

     double  smoothing_lambda  ;


     //  create  a  property-map  for  segment-ids

     typedef  std::map<Polyhedron::Facet_const_handle,  std::size_t>  Facet_int_map;

     Facet_int_map  internal_segment_map;

     boost::associative_property_map<Facet_int_map>  segment_property_map(internal_segment_map);


//Run the sdf segmentation algo

     int  nb_segments  =  SegmentPolyhedron(segment_property_map,number_of_clusters,  smoothing_lambda  ,mesh);


     std::vector  <Polyhedron>  PolySegments;

     PolySegments.resize(nb_segments);


//Get the segement of the mesh

     GetSegments(mesh,segment_property_map,nb_segments,PolySegments,0);



     vertex_iterator  vb,  ve;



//Make zeroth segment as ROI

     for(boost::tie(vb,  ve)  =  vertices(PolySegments[0]);  vb  !=  ve;  ++vb)

     {

       //std::cout  <<  __LINE__  <<  std::endl;

         insert_roi_vertex(*vb); // GIVES CRASH

     }





   }



===============================================================================


Perhaps it is because of size of deform_mesh, which was  equal to
complete non-segmented mesh size. ?

There is k-ring selection as well, which is used when picked by mouse.

Can someone suggest me some other way maybe, so that I could make the
mesh segment as ROI


Thanks to provide input.


--
Sukhraj Singh

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Sukhraj Singh