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[Pol Monsó Purtí <>]

Thanks!

I've got it:

CGAL::Object o = vd.dual().dual(e.dual());
K::Ray_2 r;
if(CGAL::assign(r,o))
    std::cout << "assigned" << std::endl;

where e is a VD::Halfedge

On Tue, Jul 19, 2016 at 4:25 PM, Sebastien Loriot (GeometryFactory) <> wrote:

The halfedge has a dual method that will gives you the Delaunay_edge you need to call the function I mentioned.

http://doc.cgal.org/latest/Voronoi_diagram_2/classCGAL_1_1Voronoi__diagram__2_1_1Halfedge.html#a55c12984864f6e688bc775220633ec63

Note you can access the underlying triangulation by calling Voronoi_diagram_2::dual();

http://doc.cgal.org/latest/Voronoi_diagram_2/classCGAL_1_1Voronoi__diagram__2.html#acd0aca0a4b4666c615e2902f71134cd1

Sebastien.



On 07/19/2016 04:21 PM, Pol Monsó Purtí wrote:

Thanks Sebastien,

If I understood your example correctly, an alternative would be to use
the voronoi's delaunay vd.dual() instead and traverse its edges to
obtain the voronoi lines/rays/segments.

It isn't possible to do it directly with the voronoi? I already have the
halfedge whose ray/line I want. They ray/line/segment should already be
defined somehow.







On Tue, Jul 19, 2016 at 3:23 PM, Sebastien Loriot (GeometryFactory)

< <mailto:>> wrote:

    This function should do what you want:

    http://doc.cgal.org/latest/Triangulation_2/classCGAL_1_1Delaunay__triangulation__2.html#a0f9dc798a43693e646e166718a0a0a82

    here is how it is used in Delaunay_triangulation_2::draw_dual()

           Finite_edges_iterator eit= this->finite_edges_begin();
           for (; eit != this->finite_edges_end(); ++eit) {
             Object o = dual(eit);
             typename Geom_traits::Line_2  l;
             typename Geom_traits::Ray_2   r;
             Segment s;
             if (CGAL::assign(s,o)) ps << s;
             if (CGAL::assign(r,o)) ps << r;
             if (CGAL::assign(l,o)) ps << l;
           }
           return ps;

    Sebastien.

    On 07/19/2016 03:05 PM, Pol Monsó Purtí wrote:

        Dear all,

        How should I convert a voronoi is_ray() to ray_2 ?

        I've found this old topic
        <http://cgal-discuss.949826.n4.nabble.com/Question-about-method-of-dealing-with-the-unbounded-half-edge-in-Voronoi-diagram-2-td2019585.html>
        but the links have rot, and it suggests a better alternative than
        buildling it up from the top-bottom sites.

        Cheers!

        Pol






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