CGAL users discussion list

[Marius Kintel <>]

Hi,

The rollback code is never reached in cases where scd.visit_shell_objects() 
throws an exception.
e.g. violated intersection constraint in Constrained_triangulation_2.

We temporarily worked around this by explicitly catching those exceptions in 
our forked version of the Build_polyhedron class.
I haven’t tested Giles’ variant, but that looks a lot cleaner that our 
attempt.

 -Marius

On Feb 19, 2015, at 05:35 AM, Sebastien Loriot (GeometryFactory) 
<>
 wrote:

> 
> Please check whether the following patch solves your problem:
> --- a/Nef_3/include/CGAL/Nef_polyhedron_3.h
> +++ b/Nef_3/include/CGAL/Nef_polyhedron_3.h
> @@ -824,6 +824,7 @@ protected:
>        if(skip_volumes-- <= 0)
>          scd.visit_shell_objects(SFace_const_handle(c->shells_begin()),V);
>       B.end_surface();
> +      if ( B.error() ) B.rollback();
>     }
> 
>   };
> @@ -977,6 +978,7 @@ protected:
>       Visitor V(B,omit_vertex, scd,VI);
>       scd.visit_shell_objects(sf, V);
>       B.end_surface();
> +      if ( B.error() ) B.rollback();
>     }
> 
>   };