CGAL users discussion list

[Matthias Preisig <>]

Sylvain Pion wrote:
>  a écrit :
> > i found a possible bug in CGAL::intersection when i try to intersect 
> > two objects of type Triangle_2. in the case where the intersection 
> > should be a triangle something doesn't work properly, the result is 
> > that i the function returns no object.
> >
> > i'm using CGAL version 3.1, but as far as i can see from the list of 
> > changes this problem hasn't been resolved in version 3.3
>
> Please try 3.3.1.  The changes list does not always go in every detail.
i realized i use CGAL-3.2.1, not 3.1. i might try 3.3.1 later. for now i 
don't want to upgrade since with that fix in 
'triangle_2_triangle_2_intersection.c' i have exactly what i need.
> > i use microsoft visual c++ compiler.
> >
> > the following code should return a Triangle_2 when i try intersecting 
> > the triangles {(0,0),(1,0),(0,1)} and {(0.1,0.1),(1.1,0.1),(0.1,1)}.
> >
> >
> >
> > #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
> > #include <CGAL/intersections.h>
> > #include <CGAL/Polygon_2.h>
> >
> > #include <fstream>
> >
> > struct K : CGAL::Exact_predicates_inexact_constructions_kernel {};
>
> What does it give for Exact_predicates_exact_constructions_kernel ?
using Exact_predicates_exact_constructions_kernel yields the same result.

matthias preisig