CGAL users discussion list

[Andreas Fabri <>]

Hi Wesley,

Maybe I get your question wrong, but there is a remove(Vertex_handle)
function in the 3D Delaunay class.

regards,

andreas

Wesley Smith wrote:
> What would it take to implement a remove() function in
> DelaunayTriangulation_3?  Are there some basic building blocks already
> in place to handle this?  I've been looking at insert_in_conflict() in
> Triangulation_3 which is what DelaunayTriangulation_3::insert() uses.
> There are a number of comments in this function refering to 'hidden'
> cells
>
> for example:
> // If the new point is not in conflict with its cell, it is hidden.
>       if (!tester.test_initial_cell(c)) {
>         hider.hide_point(c,p);
>         return Vertex_handle();
>       }
>
> // Ok, we really insert the point now.
>       // First, find the conflict region.
>       std::vector<Cell_handle> cells;
>       Facet facet;
>
>       cells.reserve(32);
>       find_conflicts
>         (c, tester, make_triple(Oneset_iterator<Facet>(facet),
>                                 std::back_inserter(cells),
>                                 Emptyset_iterator()));
>
>       // Remember the points that are hidden by the conflicting cells,
>       // as they will be deleted during the insertion.
>       hider.process_cells_in_conflict(cells.begin(), cells.end());
>
>
>       // Insertion.
>       v = tds()._insert_in_hole(cells.begin(), cells.end(),
>                                 facet.first, facet.second);
>
>       v->set_point (p);
>       // Store the hidden points in their new cells.
>       hider.reinsert_vertices(v);
>       return v;
>     }
>
>
>
> What does 'hidden' mean in this context?
>
> thanks,
> wes