TriangulationDataStructure_3::Cell Concept Reference

Definition

The concept TriangulationDataStructure_3::Cell stores four Vertex_handles to its four vertices and four Cell_handles to its four neighbors. The vertices are indexed 0, 1, 2, and 3 in consistent order. The neighbor indexed \( i\) lies opposite to vertex i.

In degenerate dimensions, cells are used to store faces of maximal dimension: in dimension 2, each cell represents only one facet of index 3, and 3 edges \( (0,1)\), \( (1,2)\) and \( (2,0)\); in dimension 1, each cell represents one edge \( (0,1)\). (See also Section Representation.)

Creation

In order to obtain new cells or destruct unused cells, the user must call the create_cell() and delete_cell() methods of the triangulation data structure.

See also

TriangulationDataStructure_3::Vertex

Types
typedef TriangulationDataStructure_3	Triangulation_data_structure
typedef TriangulationDataStructure_3::Vertex_handle	Vertex_handle
typedef TriangulationDataStructure_3::Cell_handle	Cell_handle

Access Functions
Vertex_handle	vertex (int i) const
	Returns the vertex i of c. More...
int	index (Vertex_handle v) const
	Returns the index of vertex v in c. More...
bool	has_vertex (Vertex_handle v) const
	Returns true if v is a vertex of c.
bool	has_vertex (Vertex_handle v, int &i) const
	Returns true if v is a vertex of c, and computes its index i in c.
Cell_handle	neighbor (int i) const
	Returns the neighbor i of c. More...
int	index (Cell_handle n) const
	Returns the index corresponding to neighboring cell n. More...
bool	has_neighbor (Cell_handle n) const
	Returns true if n is a neighbor of c.
bool	has_neighbor (Cell_handle n, int &i) const
	Returns true if n is a neighbor of c, and computes its index i in c.

Setting
void	set_vertex (int i, Vertex_handle v)
	Sets vertex i to v. More...
void	set_vertices (Vertex_handle v0, Vertex_handle v1, Vertex_handle v2, Vertex_handle v3)
	Sets the vertex pointers.
void	set_neighbor (int i, Cell_handle n)
	Sets neighbor i to n. More...
void	set_neighbors (Cell_handle n0, Cell_handle n1, Cell_handle n2, Cell_handle n3)
	Sets the neighbors pointers.

Checking
bool	is_valid (bool verbose=false, int level=0) const
	This is a function for debugging purpose. More...

Member Function Documentation

index() [1/2]

int TriangulationDataStructure_3::Cell::index

(

Vertex_handle

v

)

const

Returns the index of vertex v in c.

Precondition

v is a vertex of c.

index() [2/2]

int TriangulationDataStructure_3::Cell::index

(

Cell_handle

n

)

const

Returns the index corresponding to neighboring cell n.

Precondition

n is a neighbor of c.

is_valid()

bool TriangulationDataStructure_3::Cell::is_valid	(	bool	verbose = false,
		int	level = 0
	)		const

This is a function for debugging purpose.

Debugging Support

User defined local validity checking function.

neighbor()

Cell_handle TriangulationDataStructure_3::Cell::neighbor

(

int

i

)

const

Returns the neighbor i of c.

Precondition

\( i \in\{0, 1, 2, 3\}\).

set_neighbor()

void TriangulationDataStructure_3::Cell::set_neighbor	(	int	i,
		Cell_handle	n
	)

Sets neighbor i to n.

Precondition

\( i \in\{0, 1, 2, 3\}\).

set_vertex()

void TriangulationDataStructure_3::Cell::set_vertex	(	int	i,
		Vertex_handle	v
	)

Sets vertex i to v.

Precondition

\( i \in\{0, 1, 2, 3\}\).

vertex()

Vertex_handle TriangulationDataStructure_3::Cell::vertex

(

int

i

)

const

Returns the vertex i of c.

Precondition

\( i \in\{0, 1, 2, 3\}\).