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["Sebastien Loriot (GeometryFactory)" <>]

annie wrote:
> Hello,
>
> I'm trying to get geometric coordinates of vertices of segment Delaunay
> graph.
> How to plug in the proper class for vertices there?
>
> There is a class TriangulationDataStructure_2::Vertex with a member point(),
> which is used in point Delaunay graph. With segment,
> Segment_Delaunay_graph_vertex_base_2 class doesn't have one. There is also
> some rebind mechanism there. Is it possible to use class with point() for
> vertices in segment Delaunay graph? Of course I wish this method would
> return proper coordinates.
>
> I would be very grateful for any help as I'm trying hard to get vertices
> from a while...
>
> annie

The following is working for me:

SDG2::Finite_vertices_iterator it=sdg.finite_vertices_begin();
for (;it!=sdg.finite_vertices_end();++it){
  if (it->site().is_point())
    std::cout << it->site().point() << std::endl;
  if (it->site().is_segment())
    std::cout << it->site().segment() << std::endl;
}


The documentation is here:
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Segment_Delaunay_graph_2_ref/Concept_SegmentDelaunayGraphSite_2.html

If you need the exact constructions, you probably need to use the 
storage site documented here:
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Segment_Delaunay_graph_2_ref/Concept_SegmentDelaunayGraphStorageSite_2.html
The representation of output sites is given here:
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Segment_Delaunay_graph_2/Chapter_main.html#Section_42.2

S.