CGAL users discussion list

["Laurent Rineau (GeometryFactory)" <>]

Le lundi 13 février 2012 19:12:38 Garth N. Wells a écrit :
> On 13 February 2012 19:08, Laurent Rineau (GeometryFactory)
> 
> <>
>  wrote:
> > 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?
> 
> The example file has two examples and some ifdefs - my post has just
> the simple part.
> 
> The off file is the fandisk.off file that is in
> 
>     CGAL-3.9/examples/Mesh_3/data/fandisk.off

Thanks. That looks like a bug. Can you give me the result of `uname -a`? I 
will try to reproduce that bug on one of my machines, and fix it.

Does the bug occur at every run?

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