CGAL 5.6.1 - dD Triangulations
TriangulationDataStructure::FullCell Concept Reference

Definition

The concept TriangulationDataStructure::FullCell describes the type used by a TriangulationDataStructure to store the full cells.

It sets requirements of combinatorial nature only, as geometry is not concerned here. In the context of triangulation, the term full cell refers to a face of maximal dimension. This maximality characteristic is emphasized by using the adjective full.

A TriangulationDataStructure::FullCell is responsible for storing handles to the vertices of the full cell as well as handles to the adjacent full cells. Two full cells are said to be adjacent when they share a facet. Adjacent full cells are called hereafter neighbors.

Has Models:

CGAL::Triangulation_ds_full_cell<TriangulationDataStructure_, DSFullCellStoragePolicy>

CGAL::Triangulation_full_cell<TriangulationTraits_, Data, TriangulationDSFullCell_>

See also
TriangulationDataStructure::FullCell
TriangulationDataStructure::Face
TriangulationDataStructure

Types

typedef unspecified_type Vertex_handle
 A handle to a vertex, which must be the same as the nested type TriangulationDataStructure::Vertex_handle.
 
typedef unspecified_type Vertex_handle_iterator
 An iterator over the handles to the vertices of the full cell.
 
typedef unspecified_type Full_cell_handle
 A handle to a full cell, which must be the same as the nested type TriangulationDataStructure::Full_cell_handle.
 
typedef TriangulationDataStructure::Full_cell_data TDS_data
 A data member of this type has to be stored and accessible through access function below.
 

Access Functions

int maximal_dimension () const
 Returns one less than the maximum number of vertices that the full cell can store. More...
 
Vertex_handle_iterator vertices_begin () const
 Returns an iterator to the first Vertex_handle stored in the full cell.
 
Vertex_handle_iterator vertices_end () const
 Returns an iterator pointing beyond the last Vertex_handle stored in the full cell.
 
Vertex_handle vertex (const int i) const
 Returns the i-th vertex of the full cell. More...
 
Full_cell_handle neighbor (const int i) const
 Returns the full cell opposite to the i-th vertex of the full cell c. More...
 
int mirror_index (const int i) const
 Returns the index of c in its \( i^{th}\) neighbor (c.neighbor(i)). More...
 
int index (Full_cell_handle n) const
 Returns the index i such that c.neighbor(i)==n. More...
 
int index (Vertex_handle v) const
 Returns the index i of the vertex v such that c.vertex(i)==v. More...
 

Internal

Advanced

These functions are used internally by the triangulation data structure.

The user is not encouraged to use them directly as they may change in the future.

const TDS_datatds_data () const
 Returns the data member of type TDS_data. More...
 
TDS_datatds_data ()
 Same as above, but returns a reference to a non-const object.
 
Vertex_handle mirror_vertex (const int i, const int cur_dim) const
 Returns a handle to the mirror vertex of the i-th vertex of full cell c. More...
 

Update Functions

void set_vertex (const int i, Vertex_handle v)
 Sets the \( i\)-th vertex of the full cell. More...
 
void set_neighbor (const int i, Full_cell_handle n)
 Sets the i-th neighbor of c to n. More...
 
void set_mirror_index (const int i, const int index)
 Sets the mirror index of the \( i\)-th vertex of c to index. More...
 
void swap_vertices (int d1, int d2)
 Switches the orientation of the full cell c by swapping its vertices with index d1 and d2. More...
 

Queries

bool has_vertex (Vertex_handle v) const
 Returns true if the vertex v is a vertex of the full cell c. More...
 
bool has_vertex (Vertex_handle v, int &ret) const
 Returns true and sets the value of ret to the index of v in c if the vertex v is a vertex of the full cell c. More...
 
bool has_neighbor (Full_cell_handle n) const
 Returns true if the full cell n is a neighbor of the full cell c. More...
 
bool has_neighbor (Full_cell_handle n, int &ret) const
 Returns true and sets the value of ret to the index of n as a neighbor of c if the full cell n is a neighbor of the full cell c. More...
 

Validity Check

bool is_valid (bool verbose=false) const
 This is a function for debugging purpose. More...
 

Input/Output

These operators can be used directly and are called by the I/O operator of class TriangulationDataStructure.

template<class TriangulationDataStructure >
std::ostream & operator<< (std::ostream &os, const Triangulation_ds_full_cell< TriangulationDataStructure > &c)
 Writes (possibly) non-combinatorial information about full cell c to the stream os.
 
template<class TriangulationDataStructure >
std::istream & operator>> (std::istream &is, Triangulation_ds_full_cell< TriangulationDataStructure > &c)
 Reads from stream is the full cell information written by operator<<.
 

Member Function Documentation

◆ has_neighbor() [1/2]

bool TriangulationDataStructure::FullCell::has_neighbor ( Full_cell_handle  n) const

Returns true if the full cell n is a neighbor of the full cell c.

Returns false otherwise.

◆ has_neighbor() [2/2]

bool TriangulationDataStructure::FullCell::has_neighbor ( Full_cell_handle  n,
int &  ret 
) const

Returns true and sets the value of ret to the index of n as a neighbor of c if the full cell n is a neighbor of the full cell c.

Returns false otherwise.

◆ has_vertex() [1/2]

bool TriangulationDataStructure::FullCell::has_vertex ( Vertex_handle  v) const

Returns true if the vertex v is a vertex of the full cell c.

Returns false otherwise.

◆ has_vertex() [2/2]

bool TriangulationDataStructure::FullCell::has_vertex ( Vertex_handle  v,
int &  ret 
) const

Returns true and sets the value of ret to the index of v in c if the vertex v is a vertex of the full cell c.

Returns false otherwise.

◆ index() [1/2]

int TriangulationDataStructure::FullCell::index ( Full_cell_handle  n) const

Returns the index i such that c.neighbor(i)==n.

Precondition
n must be a neighbor of c.

◆ index() [2/2]

int TriangulationDataStructure::FullCell::index ( Vertex_handle  v) const

Returns the index i of the vertex v such that c.vertex(i)==v.

Precondition
v must be a vertex of the c.

◆ is_valid()

bool TriangulationDataStructure::FullCell::is_valid ( bool  verbose = false) const

This is a function for debugging purpose.

Debugging Support

Performs some validity checks on the full cell c.

It must at least check that for each existing neighbor n, c is also a neighbor of n.

Returns true if all the tests pass, false if any test fails. See the documentation for the models of this concept to see the additional (if any) validity checks that they implement.

◆ maximal_dimension()

int TriangulationDataStructure::FullCell::maximal_dimension ( ) const

Returns one less than the maximum number of vertices that the full cell can store.

This does not return the dimension of the actual full cell stored in c.

◆ mirror_index()

int TriangulationDataStructure::FullCell::mirror_index ( const int  i) const

Returns the index of c in its \( i^{th}\) neighbor (c.neighbor(i)).

If the returned integer is not negative, it holds that c.neighbor(i)->neighbor(j) == c. Returns -1 if c has no adjacent full cell of index i.

Precondition
\(0 \leq i \leq \) maximal_dimension().

◆ mirror_vertex()

Vertex_handle TriangulationDataStructure::FullCell::mirror_vertex ( const int  i,
const int  cur_dim 
) const

Returns a handle to the mirror vertex of the i-th vertex of full cell c.

cur_dim is the current dimension of the triangulation data structure.

Advanced

This function works even if the adjacency information stored in the neighbor full cell *c.neighbor(i) is corrupted. This is useful when temporary corruption is necessary during surgical operations on a triangulation.

Precondition
\(0 \leq i,\) cur_dim \( \leq \) maximal_dimension().

◆ neighbor()

Full_cell_handle TriangulationDataStructure::FullCell::neighbor ( const int  i) const

Returns the full cell opposite to the i-th vertex of the full cell c.

Precondition
\(0 \leq i \leq \)maximal_dimension().

◆ set_mirror_index()

void TriangulationDataStructure::FullCell::set_mirror_index ( const int  i,
const int  index 
)

Sets the mirror index of the \( i\)-th vertex of c to index.

This corresponds to the index, in c->neighbor(i), of the full cell c.

Note: a model of this concept may choose not to store mirror indices, in which case this function should do nothing.

Precondition
\(0 \leq i \leq \)maximal_dimension().

◆ set_neighbor()

void TriangulationDataStructure::FullCell::set_neighbor ( const int  i,
Full_cell_handle  n 
)

Sets the i-th neighbor of c to n.

Full cell n is opposite to the \( i\)-th vertex of c.

Precondition
\(0 \leq i \leq \)maximal_dimension().

◆ set_vertex()

void TriangulationDataStructure::FullCell::set_vertex ( const int  i,
Vertex_handle  v 
)

Sets the \( i\)-th vertex of the full cell.

Precondition
\(0 \leq i \leq \) maximal_dimension().

◆ swap_vertices()

void TriangulationDataStructure::FullCell::swap_vertices ( int  d1,
int  d2 
)

Switches the orientation of the full cell c by swapping its vertices with index d1 and d2.

Precondition
\(0 \leq d1,d2 \leq \)maximal_dimension().

◆ tds_data()

const TDS_data& TriangulationDataStructure::FullCell::tds_data ( ) const

Returns the data member of type TDS_data.

It is typically used to mark the full cell as visited during operations on a TriangulationDataStructure.

◆ vertex()

Vertex_handle TriangulationDataStructure::FullCell::vertex ( const int  i) const

Returns the i-th vertex of the full cell.

Precondition
\(0 \leq i \leq \) maximal_dimension().