CGAL 5.2.2 - 2D Arrangements
ArrangementDcelFace Concept Reference

Definition

A face record in a Dcel data structure. A face may either be unbounded, otherwise it has an incident halfedge along the chain defining its outer boundary. A face may also contain holes and isolated vertices in its interior.

See also
ArrangementDcel
ArrangementDcelVertex
ArrangementDcelHalfedge

Types

The non-mutable iterators Hole_const_iterator, and Isolated_vertex_const_iterator are also defined.

typedef unspecified_type Vertex
 the corresponding Dcel vertex type.
 
typedef unspecified_type Halfedge
 the corresponding Dcel halfedge type.
 
typedef unspecified_type Hole_iterator
 a bidirectional iterator over the holes in inside the face. More...
 
typedef unspecified_type Isolated_vertex_iterator
 a bidirectional iterator over the isolated vertices in inside the face. More...
 

Creation

 Arr_dcel_face ()
 default constructor.
 
void assign (const Self &other)
 assigns f with the contents of the other face.
 

Access Functions

All functions below also have const counterparts, returning non-mutable pointers or iterators:

bool is_unbounded () const
 returns whether the face is unbounded.
 
Halfedgehalfedge ()
 returns an incident halfedge along the outer boundary of the face. More...
 
size_t number_of_holes () const
 returns the number of holes inside f.
 
Hole_iterator holes_begin ()
 returns a begin-iterator for the holes inside f.
 
Hole_iterator holes_end ()
 returns a past-the-end iterator for the holes inside f.
 
size_t number_of_isolated_vertices () const
 returns the number of isolated vertices inside f.
 
Isolated_vertex_iterator isolated_vertices_begin ()
 returns a begin-iterator for the isolated vertices inside f.
 
Isolated_vertex_iterator isolated_vertices_end ()
 returns a past-the-end iterator for the isolated vertices inside f.
 

Modifiers

void set_unbounded (bool flag)
 sets the face as unbounded (if flag is true), or as a bounded face (if it is false).
 
void set_halfedge (Halfedge *e)
 sets the incident halfedge.
 
void add_hole (Halfedge *e)
 adds e as a hole inside f.
 
void erase_hole (Hole_iterator it)
 removes the hole that it points to from inside f.
 
void add_isolated_vertex (Vertex *v)
 adds v as an isolated vertex inside f.
 
void erase_isolated_vertex (Isolated_vertex_iterator it)
 removes the isolated vertex that it points to from inside f.
 

Member Typedef Documentation

◆ Hole_iterator

a bidirectional iterator over the holes in inside the face.

Its value-type is Halfedge*.

◆ Isolated_vertex_iterator

a bidirectional iterator over the isolated vertices in inside the face.

Its value-type is Vertex*.

Member Function Documentation

◆ halfedge()

Halfedge* ArrangementDcelFace::halfedge ( )

returns an incident halfedge along the outer boundary of the face.

If f has no outer boundary, the function returns nullptr.