BGLGraphExternalIndices

A number of BGL and CGAL algorithms require the graph to have (initialized) integer-like indices for its vertices, edges, or faces. However, not all graphs intrinsically offer a natural way to attach a unique ID to each element. The following classes and functions paliate this by attaching and initializing external IDs to the elements of the graph.

Classes
class	CGAL::HalfedgeDS_face_max_base_with_id< Refs >
class	CGAL::HalfedgeDS_halfedge_max_base_with_id< Refs >
class	CGAL::HalfedgeDS_vertex_max_base_with_id< Refs >
struct	CGAL::Linear_cell_complex_bgl_min_items
struct	CGAL::Linear_cell_complex_for_bgl_combinatorial_map_helper< d, d2, LCCTraits, Alloc >
class	CGAL::Polyhedron_items_with_id_3
class	CGAL::Triangulation_face_base_with_id_2< TriangulationTraits_2, TriangulationFaceBase_2 >
class	CGAL::Triangulation_vertex_base_with_id_2< TriangulationTraits_2, TriangulationVertexBase_2 >

Functions
template<class HalfedgeDS_with_id >
void	CGAL::set_halfedgeds_items_id (Polyhedron_with_id &P)
template<typename Triangulation >
void	CGAL::set_triangulation_ids (Triangulation &tr)

Function Documentation

set_halfedgeds_items_id()

template<class HalfedgeDS_with_id >

void CGAL::set_halfedgeds_items_id

(

Polyhedron_with_id &

P

)

#include <CGAL/Polyhedron_items_with_id_3.h>

Given a CGAL::Polyhedron_3, for each simplex type (vertex, halfedge, facet) associates an index from 0 to the number of simplices minus 1 to each simplex of hds. All simplex types must provide an id() method return a reference to a variable that can be assigned a std::size_t. An item class suited for this use is CGAL::Polyhedron_items_with_id_3.

set_triangulation_ids()

template<typename Triangulation >

void CGAL::set_triangulation_ids

(

Triangulation &

tr

)

#include <CGAL/Triangulation_face_base_with_id_2.h>

This function initializes vertex, edge, and face indices of the triangulation tr and must be called prior to using tr as a BGL graph in an algorithm that requires vertex, halfedge, edge, or face indices.

Template Parameters

Triangulation

a 2D triangulation of CGAL, whose combinatorial data structure has been initialized with the vertex and face classes Triangulation_vertex_base_with_id_2 and Triangulation_face_base_with_id_2.

See also

the PkgTriangulation2 package