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[Mael Rouxel-Labbé <>]

Hello,

By definition the ray has a source or a target, and you can get the 
direction because the Voronoi edge is orthogonal to the Delaunay edge. 
Hence, something like:

      ...
      Delaunay_vertex_const_handle v1 = he->up();
      Delaunay_vertex_const_handle v2 = he->down();
      Vector_2 direction(v1->point().y() - v2->point().y(), point().x() 
- v1->point().x());
      ...

Exception to that is if you are in dimension 1, but then the line is 
orthogonal to the segment and passing through the middle of the Delaunay 
edge.

Best,
Mael

On 01/05/2021 21:45, HEKTO ( via cgal-discuss 
Mailing List) wrote:
> I'm getting familiar with Voronoi diagrams in 2D. The following code fragment
> outputs sources and targets for *bounded* halfedges:
>
>    const std::list<Site> sv;
> // <=== sites are here
>    const VD vd(sv.cbegin(), sv.cend());                                 //
> <=== VD is a regular 'Voronoi_diagram_2'
>    for (auto fit = vd.faces_begin(); fit != vd.faces_end(); ++fit)
>    {
>      const auto heitBeg = fit->ccb();
>      auto heit = heitBeg;
>      do
>      {
>        if (heit->has_source()) cout << heit->source()->point() << endl;
>        if (heit->has_target()) cout << heit->target()->point() << endl;
>      } while (++heit != heitBeg);
>    }
>
> However I don't see how I can get any ray directions for halfedges, which
> don't have source or target.
> Could you please advise?
>
>
>
>
> --
> Sent from: http://cgal-discuss.949826.n4.nabble.com/