CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

schlady wrote:
> mr_hell wrote:
> > I have some troubles with filling CGAL::Delaunay_triangulation_2 with
> > vertices using info() in vertex handle.
> > Normally i use this kind of code
> >
> > for(int i = 0; i < inp_pointscount; i++){
> > 		Delaunay2::Vertex_handle vert =  
> > triangulation.insert(DelaunayPoint2(inputpoints[i].x,inputpoints[i].y));
> >                 vert->info() = i;
> > }
> >
> > but in this case each triangulation.insert call causes triangulation
> > recalculation, so i have inp_pointscount triangulation calls instead of
> > one, and it takes more time to get result.
> >
> > and this code
> >
> > triangulation.insert(pointlist.begin(), pointlist.end());
> >
> > int count = 0;
> >         for(Delaunay2::Finite_vertices_iterator v_it =
> > triangulation.finite_vertices_begin(); v_it !=
> > triangulation.finite_vertices_end(); ++v_it, count++) 
> > 		v_it->info() = count;
> >
> > doesnt work correctly.
> >
> > how to fill info() field, get correct results and call triangulation only
> > one time?
>
> Hello list,
>
> I am also having the same problem. 
> I try to assign unique indices to the Delaunay vertices by using info().
>
> Is there a way to fill the info() field by using the iterator version of the
> insert method?
Have a look here for a solution in 3D:
https://lists-sop.inria.fr/sympa/arc/cgal-discuss/2010-01/msg00004.html

An integrated solution may be in the next release of CGAL.

> I also would like to know, does the vertex iterator preserve the same order
> of vertices/points as I inserted them?

Points are first sorted using CGAL::spatial_sort  documented here:
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Spatial_sorting_ref/Function_spatial_sort.html
More details here:
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Spatial_sorting/Chapter_main.html

S.
> Cheers,
> Jens