CGAL users discussion list

[Olivier Devillers <>]

> > - for each tetrahedron on the convex hull, the index (local index, 
> > i.e. in
> > 1-4) of the vertex NOT on the convex hull
> Iterate over infinite cells
> (use the range all_cells_begin(),all_cell_end() and the 
> is_infinite(Cell_handle) function documented in [1])
> For each such cell, get the index of the infinite vertex,
> using int i=cell->index(t.infinite_vertex()). Then use
> Facet f=t.mirror_facet( Facet_3(cell,i) );
> where Facet is
> "typedef std::pair<Cell_handle, int>  Facet;
>  (c,i) is the facet of c opposite to the vertex of index i"
> as documented in [2]

It gives for each facet (triangle) on the convex hull the finite vertex 
that makes a Delaunay
tetrahdron with this facet. Notice that it is possible that this vertex 
is on the convex hull.