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[Sukhraj Singh <>]

Please find the Surface Mesh Deformation Plugin Code having the changes as attachment.

I think you should be able to find my changes using some code comparison tool. Else let me know.

It is based on 4.8.1 tag.

A function which is worth noting is as below. In which I get the crash.

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

//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

    }

  }

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

The approach I am following right now is, if you replace the for loop above with the below code. Also commenting the GetSegments() call, as it will not be required.

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

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());
 }
} ===============================================================================

Thanks !!

On Wed, Sep 7, 2016 at 2:52 AM, Sebastien Loriot (GeometryFactory) <> wrote:

I see no error in this code, which is why a minimal example showing the pb would be great.

Sebastien.

On 09/05/2016 03:29 PM, Sukhraj Singh wrote:

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)

< <mailto:>> 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

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Attachment: Surface_mesh_deformation_4.8.1++.tar.gz
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