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["Sebastien Loriot (GeometryFactory)" <>]

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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