CGAL users discussion list

[Adam Getchell <>]

Hello all,

I’m searching for documentation on these two functions to determine if I am using them correctly. What is the difference between them? (What makes a particular check expensive?)

I have code which does a (2,6) Pachner move that starts out as:

void move_26(Delaunay* const D3,

             Cell_handle one_three_simplex,

             unsigned neighbor_index,

             Cell_handle three_one_simplex) noexcept {

  // Preconditions

  CGAL_triangulation_precondition((dimension() == 3)

                                   && (0 <= neighbor_index)

                                   && (neighbor_index < 4));

  CGAL_triangulation_precondition(one_three_simplex.has_neighbor

                                  (three_one_simplex));

  CGAL_triangulation_expensive_precondition(is_cell(one_three_simplex,

                                                    three_one_simplex));

  // Get vertices of common face

  unsigned i1 = (neighbor_index + 1)&3;

  unsigned i2 = (neighbor_index + 2)&3;

  unsigned i3 = (neighbor_index + 3)&3;

Adam Getchell
about.me/adamgetchell