CGAL 6.0.1  2D Arrangements

A vertex record in a DCEL data structure. A vertex is always associated with a point. However, the vertex record only stores a pointer to the associated point, and the actual Point
object is stored elsewhere.
A vertex usually has several halfedges incident to it, such that it is possible to access one of these halfedges directly and to traverse all incident halfedges around the vertex. However, the DCEL may also contain isolated vertices that have no incident halfedges. In this case, the vertex stores an isolated vertexinformation record, indicating the face that contains this vertex in its interior.
Types  
typedef unspecified_type  Halfedge 
the corresponding DCEL halfedge type.  
typedef unspecified_type  Isolated_vertex 
the corresponding DCEL isolated vertexinformation type.  
typedef unspecified_type  Point 
the point type associated with the vertex.  
Creation  
Arr_dcel_vertex ()  
default constructor.  
void  assign (const Self &other) 
assigns v with the contents of the other vertex.  
Access Functions  
All functions below also have  
bool  is_isolated () const 
returns whether the vertex is isolated (has no incident halfedges).  
Halfedge *  halfedge () 
returns an incident halfedge that has v as its target.  
Isolated_vertex *  isolated_vertex () 
returns the isolated vertexinformation record.  
bool  has_null_point () const 
returns whether the vertex is not associated with a valid point (i.e. it lies at infinity).  
Point &  point () 
returns the associated point.  
Arr_parameter_space  parameter_space_in_x () const 
returns the placement of the \( x\)coordinate in the parameter space, that is, either the left boundaryside, the interior, or the right boundaryside.  
Arr_parameter_space  parameter_space_in_y () const 
returns the placement of the \( y\)coordinate in the parameter space, that is, either the bottom boundaryside, the interior, or the top boundaryside.  
Modifiers  
void  set_halfedge (Halfedge *e) 
sets the incident halfedge, marking v as a regular vertex.  
void  set_isolated_vertex (Isolated_vertex *iv) 
sets the isolated vertexinformation record, marking v as an isolated vertex.  
void  set_point (Point *p) 
sets the associated point.  
void  set_boundary (Arr_parameter_space inf_x, Arr_parameter_space inf_y) 
sets v as a vertex on a boundary side.  
Halfedge * ArrangementDcelVertex::halfedge  (  ) 
returns an incident halfedge that has v
as its target.
v
is not an isolated vertex. Isolated_vertex * ArrangementDcelVertex::isolated_vertex  (  ) 
returns the isolated vertexinformation record.
v
is an isolated vertex. Point & ArrangementDcelVertex::point  (  ) 
returns the associated point.
v
() is associated with a valid point. void ArrangementDcelVertex::set_boundary  (  Arr_parameter_space  inf_x, 
Arr_parameter_space  inf_y  
) 
sets v
as a vertex on a boundary side.
inf_x
or inf_y
is not ARR_INTERIOR
.