CGAL users discussion list

[Panagiotis Foteinos <>]

Hello yall!

I am developing my own Delaunay refinement technique and I am stuck debugging. Therefore, I would like to be sure that I understand quite well how CGAL updates the new cells.

In few words, I would like to know after removal or insertion which cells are not valid any more.
A valid cell is a cell that either does not belong to the triangulation any more or accommodates a different tetrahedron than it accommodated before the operation (removal or insertion).


........
........
Delaunay_Triangulation_3 T;


My_Removal(Vertex_handle v)
{
       1)  std::list<Cell_handle> to_be_invalid_cells;  //these are the only cells that will not be valid after the removal.
       2)  T.incident_cells(v, invalid_cells);

            //do something with those incident cells stored in to_be_invalid_cells;

       3)  std::list<Vertex_handle> vertices_list;  //the vertices that the new cells will consist of.
       4)  T.incident_vertices(v, vertices_list);

       5)  T.remove(v);  //remove the vertex for real.

       6) find the cells that consist only with the vertices stored in vertices_list; //these are the new cells.
       
           //do something with the new cells found right above;
       
}


My_Insertion(Point p)
{
       1)  std::list<Cell_handle> to_be_invalid_cells;  //these are the only cells that are not be valid after the insertion.
       2)  T.find_conflicts(v, cells_list);

            //do something with those cells stored in to_be_invalid_cells;

       3)  Vertex_handle v = T.insert(p);  //insert the point for real.

       4)  std::list<Cell_handle> new_cells;  //these will be the new cells.
       5)  T.incident_cells(v, new_cells);
       
           //do something with the new cells found right above;
       
}


Do I capture the to be invalid and new cells correctly?

Hope I was clear,
Regards,

Panagiotis