CGAL users discussion list

["Laurent Rineau (GeometryFactory)" <>]

Le lundi 13 février 2012 19:03:21 Garth N. Wells a écrit :
> On 8 February 2012 19:17, Garth N. Wells 
> <>
>  wrote:
> > On 8 February 2012 10:43, Laurent Rineau (GeometryFactory)
> > 
> > <>
> >  wrote:
> >> Le mardi 07 février 2012 12:22:52 Garth Wells a écrit :
> >>> I've been running into some issues with mesh generation in 3D. I'm
> >>> creating
> >>> meshes of rather simple polyhedra (tetrahedra, cubes), but have been
> >>> finding that the generation randomly fails at times. I'm also seeing a
> >>> dependency on the gcc version and optimisation level. The code at the
> >>> end of this message, taken from
> >>> 
> >>> 
> >>> http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Mesh_3/Chapter_ma
> >>> in.h tml#Subsection_50.3.5
> >>> 
> >>> runs without error with g++ 4.6.1, but with g++ 4.4.6 and the -O2 or -O3
> >>> flag I get the error
> >>> 
> >>>     terminate called after throwing an instance of
> >>> 'CGAL::Precondition_exception'
> >>>       what():  CGAL ERROR: precondition violation!
> >>>     Expr: index != Subdomain_index()
> >>>     File:
> >>> /usr/include/CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h
> >>>     Line: 160
> >>>     Aborted
> >>> 
> >>> I've tested with CGAL 3.8 and 3.9. The code is compiled using
> >>> 
> >>>     g++ -O2 -frounding-math  test.cpp -lCGAL -lboost_thread -lmpfr -lgmp
> >>> 
> >>> Any help with this would be greatly appreciated.
> >> 
> >> Can you please add:
> >> 
> >> #define CGAL_MESH_3_VERBOSE 1
> >> 
> >> as the first line of your cpp file, recompile, and give us the output of
> >> the run, when it fails?
> > 
> > It get:
> > 
> > Inserting protection balls...
> > insert_corners() done. Nb of points in triangulation: 25
> > insert_balls_on_edges() done. Nb of points in triangulation: 610
> > refine_balls() done. Nb of points in triangulation: 616
> > 
> > Start surface scan...end scan. [Bad facets:1202]
> > 
> > Refining Surface...
> > Legende of the following line: (#vertices,#steps,#facets to
> > refine,#tets to refine)
> > (1741,1124,0,0) (328.6 vertices/s)))
> > Total refining surface time: 3.42021s
> > 
> > Start volume scan...end scan. [Bad tets:2643]
> > 
> > Refining...
> > Legende of the following line: (#vertices,#steps,#facets to
> > refine,#tets to refine)
> > (1742,1,0,2642) (250.0 vertices/s)terminate called after throwing an
> > instance of 'CGAL::Precondition_exception'
> >  what():  CGAL ERROR: precondition violation!
> > Expr: index != Subdomain_index()
> > File: /usr/include/CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h
> > Line: 160
> > Aborted
> 
> Considering that the failing example code comes from the CGAL
> examples, I suppose that it should be considered a CGAL bug. Is there
> a bug tracker where I can report it as a bug?

Sorry, I forgot your mail. 

It seems you have modified the example. What off file have you used?

-- 
Laurent Rineau, PhD
R&D Engineer at GeometryFactory           http://www.geometryfactory.com/
Release Manager of the CGAL Project       http://www.cgal.org/