CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

Hello Costas,

Costas Tsirogiannis wrote:
>  I am trying to find a "fast" way to do the following:
>
> Given an object t of type Triangulation_2  create a Polyhedron_3 which has
> the same vertex and edge set
> as t.
A fast solution is to use the Polyhedron_incremental_builder.
(http://www.cgal.org/Manual/last/doc_html/cgal_manual/Polyhedron_ref/Class_Polyhedron_incremental_builder_3.html)
Iterator over finite triangulation vertices to insert them in the
Polyhedron_incremental_builder (maintain a map<T2::Vertex*,unsigned> to
get the insertion order).
then iterate over triangulation finite facets and create facets using 
the map to get the vertex indices.

S.

>  Looking at the BGL interface for CGAL, I was thinking to use  either the
> copy_graph command with a custom
> VertexCopier function or use the Boost DFS algorithm on the Triangulation
> while handling the addition of edges
> on the Polyhedron with a customized visitor.  But I'm not sure if this is
> supposed to work since there doesn't
> seem to be some way to create a vertex in your target graph (here: the
> Polyhedron) so that you can set any of 
> the member values of this vertex (e.g. to enter the coordinates of the 3D
> point associated with this vertex ).
>