CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

Did you try the AABB-tree and the closest_point() method?

https://doc.cgal.org/latest/AABB_tree/#title6

Best regards,

Sebastien.

On 9/23/20 4:17 PM, "Grimm, Raphael (IAR)" ( via 
cgal-discuss Mailing List) wrote:
> Hello,
>
> I have a non-convex mesh and want to check whether a point is within a 
> certain distance of it. Since distance queries are slow, I decided to 
> inflate the mesh and check whether the point is inside.
>
> Scaling does not work, since my mesh is concave.
>
> I did some looking around and came across minkowski_sum_3. I am planning 
> to use a sphere to inflate my original mesh by using minkowski_sum_3.
>
> I wrote some simple test for minkowski_sum_3 that adds a tetrahedron to 
> a cube (code is attached).
>
> This test crashes with a segfault. Here is the stack trace:
>
> 1  CGAL::SNC_FM_decorator<CGAL::SNC_structure<CGAL::Epick, 
> CGAL::SNC_indexed_items, 
> bool>>::determine_facet                                                          
> stl_vector.h                           805  0x55555559244a
>
> 2  CGAL::SNC_FM_decorator<CGAL::SNC_structure<CGAL::Epick, 
> CGAL::SNC_indexed_items, 
> bool>>::create_facet_objects                                                     
> In_place_list.h                        84   0x5555555a0dea
>
> 3  CGAL::SNC_external_structure<CGAL::SNC_indexed_items, 
> CGAL::SNC_structure<CGAL::Epick, CGAL::SNC_indexed_items, 
> bool>>::categorize_facet_cycles_and_create_facets 
> stl_list.h                             953  0x5555555a16d7
>
> 4  CGAL::SNC_external_structure<CGAL::SNC_indexed_items, 
> CGAL::SNC_structure<CGAL::Epick, CGAL::SNC_indexed_items, 
> bool>>::build_external_structure                  
> In_place_list.h                        310  0x5555555c3417
>
> 5  CGAL::Nef_polyhedron_3<CGAL::Epick, CGAL::SNC_indexed_items, 
> bool>::build_external_structure                                                                      
> SNC_const_decorator.h                  125  0x5555555f6188
>
> 6  CGAL::Nef_polyhedron_3<CGAL::Epick, CGAL::SNC_indexed_items, 
> bool>::delegate                                                                                      
> Nef_polyhedron_3.h                     1071 0x5555555f6188
>
> 7  
> CGAL::bipartite_nary_union_sorted_combined<CGAL::Nef_polyhedron_3<CGAL::Epick, 
> CGAL::SNC_indexed_items, 
> bool>>                                                    
> bipartite_nary_union_sorted_combined.h 214  0x5555555f6188
>
> 8  CGAL::minkowski_sum_3<CGAL::Nef_polyhedron_3<CGAL::Epick, 
> CGAL::SNC_indexed_items, bool>>                                
>                                           In_place_list.h                        309  0x5555555f7384
>
> 9  
> main                                                                                                                                                    
>            minkowski_sum_3.cpp                    81   0x55555555d8df
>
> 10 
> __libc_start_main                                                                                                                                                 
> libc-start.c                           310  0x7ffff69ccb97
>
> 11 _start
>
> I have two questions:
>
> 1.Is there a better (more efficient) way to do this?
>
> 2.If not, how can I fix the segfault / what am I doing wrong?
>
> I appreciate any hints.
>
> Best
>
> Raphael
>
> ----
>
> Karlsruhe Institute of Technology (KIT)
>
> Institute for Anthropomatics and Robotics (IAR)
>
> High Performance Humanoid Technologies (H2T)
>
> Raphael Grimm (M.Sc.)
>
> Research Scientist
>
> Adenauerring 2
>
> Building 50.20, Room 334
>
> 76131 Karlsruhe, Germany
>
> Phone: +49 721 608-47133
>
> Fax: +49 721 608-48270
>
> Email: 
>
> Web: https://www.humanoids.kit.edu
>
> KIT - The Research University in the Helmholtz Association