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["Sebastien Loriot (GeometryFactory)" <>]

Use the functor version, it will be safer.

You can do:

Kernel::Intersect_3 inter = Kernel().intersect_3_object();
Kernel::Do_intersect_3 do_inter = Kernel().do_intersect_3_object();

Then call CGAL::Object inter(sg1,sg2);

The problem is coming from a too general overload of intersection
function that has been added. Anyway I think for derived objects, using
functor is the best way to proceed as the Kernel is then specified and
you should not have problem then.


S.

On 04/12/2011 07:48 PM, S. Gerace wrote:
> class Segment_2D : public CGAL::Segment_2
> {
> public:
>
>      // Constructs a new Segment2D with a given start and end coordinates
>      inline Segment_2D(const CGAL::Point_2&p,
>                        const CGAL::Point_2&q)
>          : CGAL::Segment_2(p, q) { }
> };
>
> void CgalInheritanceTest()
> {
>      typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
>
>      // Using CGAL classes with CGAL::intersection works fine
>      CGAL::Segment_2 s1(CGAL::Point_2(0,0), CGAL::Point_2(1,1));
>      CGAL::Segment_2 s2(CGAL::Point_2(0,0.5), CGAL::Point_2(1,0.5));
>      bool doesIntersect = CGAL::do_intersect(s1, s2);
>      CGAL::Object result = CGAL::intersection(s1, s2);
>
>      std::cout<<  "Did intersect: "<<  doesIntersect<<  std::endl;
>      std::cout<<    "Found intersection: "<<  !(result.is_empty())<<
> std::endl<<  std::endl;
>
>
>      // Using child classes of CGAL classes with CGAL::intersection does not
> work
>      Segment_2D sg1(CGAL::Point_2(0,0), CGAL::Point_2(1,1));
>      Segment_2D sg2(CGAL::Point_2(0,0.5), CGAL::Point_2(1,0.5));
>
>      bool doesIntersect2 = CGAL::do_intersect(sg1, sg2); // This call works
> fine
>      CGAL::Object result2 = CGAL::intersection(sg1, sg2); // Compile error:
> conversion from CGAL::Null_tag to non-scalar type CGAL::Object with CGAL 3.7
>
>      std::cout<<  "Did intersect: "<<  doesIntersect2<<  std::endl;
>      std::cout<<    "Found intersection: "<<  !(result2.is_empty())<<
> std::endl;
> }