CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr > Class Template Reference

#include <CGAL/Conforming_constrained_Delaunay_triangulation_3.h>

Definition

template<typename Traits, typename Tr = CGAL::Default>
class CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >

This class template represents a 3D conforming constrained Delaunay triangulation.

It contains a data member of type Tr and provides additional functionality for handling polygonal constraints during the triangulation process.

Template Parameters

Traits

is the geometric traits class and must be a model of ConformingConstrainedDelaunayTriangulationTraits_3.

Tr

is the underlying triangulation class. It must be CGAL::Default or an instance of the CGAL::Triangulation_3 class template with the same Traits template parameter. Its Vertex type must be a model of ConformingConstrainedDelaunayTriangulationVertexBase_3, and its Cell type must be a model of ConformingConstrainedDelaunayTriangulationCellBase_3. The default value is Triangulation_3<Traits, TDS> where TDS is Triangulation_data_structure_3<Conforming_constrained_Delaunay_triangulation_vertex_base_3<Traits>, Conforming_constrained_Delaunay_triangulation_cell_base_3<Traits>>.

Examples

Constrained_triangulation_3/ccdt_3_after_autorefinement.cpp, Constrained_triangulation_3/ccdt_3_preprocessing.cpp, and Constrained_triangulation_3/remesh_constrained_Delaunay_triangulation_3.cpp.

Public Types
using	Triangulation = typename CGAL::Default::Get< Tr, Triangulation_3< Traits, Triangulation_data_structure_3< Conforming_constrained_Delaunay_triangulation_vertex_base_3< Traits >, Conforming_constrained_Delaunay_triangulation_cell_base_3< Traits > > > >::type
	The internal triangulation type.
using	Vertex_handle = typename Triangulation::Vertex_handle
using	size_type = typename Triangulation::size_type
using	Constrained_facets_iterator = unspecified_type
	A bidirectional iterator for visiting all constrained facets of the triangulation.
using	Constrained_facets_range = CGAL::Iterator_range< Constrained_facets_iterator >
	defines a range type for iterating over the constrained facets.

Constructors
Conforming_constrained_Delaunay_triangulation_3 can be constructed from either a polygon soup or a polygon mesh. Input Data The input data requirements are described in the documentation of the function templates.
	Conforming_constrained_Delaunay_triangulation_3 ()
	Default constructor.
template<typename PolygonMesh , typename NamedParameters = CGAL::parameters::Default_named_parameters>
	Conforming_constrained_Delaunay_triangulation_3 (const PolygonMesh &mesh, const NamedParameters &np=parameters::default_values())
	creates a 3D constrained Delaunay triangulation conforming to the faces of a polygon mesh, following the same API and requirements as the function template make_conforming_constrained_Delaunay_triangulation_3().
template<typename PointRange , typename PolygonRange , typename NamedParams = parameters::Default_named_parameters>
	Conforming_constrained_Delaunay_triangulation_3 (const PointRange &points, const PolygonRange &polygons, const NamedParams &np=parameters::default_values())
	creates a 3D constrained Delaunay triangulation conforming to the faces of a polygon soup, following the same API and requirements as the function template make_conforming_constrained_Delaunay_triangulation_3().

Accessors for the Underlying Triangulation
const Triangulation &	triangulation () const &
	returns a const reference to the underlying triangulation.
Triangulation	triangulation () &&
	moves and returns the underlying triangulation, then clears the object.

Accessors for Constrained Facets
bool	is_facet_constrained (const typename Triangulation::Facet &f) const
	returns whether a facet is constrained or not.
bool	is_facet_constrained (typename Triangulation::Cell_handle ch, int index) const
	same as is_facet_constrained(f) with f being Triangulation::Facet(ch, index).
CDT_3_signed_index	face_constraint_index (typename Triangulation::Cell_handle ch, int i) const
	same as face_constraint_index(f) with f being Triangulation::Facet(ch, index).
CDT_3_signed_index	face_constraint_index (const typename Triangulation::Facet &f) const
	returns the index of the constraint that constrains the facet f
Triangulation::size_type	number_of_constrained_facets () const
	returns the number of constrained facets in the triangulation.
Constrained_facets_iterator	constrained_facets_begin () const
	returns an iterator to the start of the sequence of constrained facets.
Constrained_facets_iterator	constrained_facets_end () const
	returns the past-the-end iterator of the sequence of constrained facets.
Constrained_facets_range	constrained_facets () const
	returns a range of the constrained facets.

Checking
These methods are mainly a debugging help for the users of advanced features.
bool	is_valid (bool verbose=false) const
	returns whether the triangulation is valid.

Member Typedef Documentation

Constrained_facets_iterator

template<typename Traits , typename Tr = CGAL::Default>

using CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::Constrained_facets_iterator = unspecified_type

A bidirectional iterator for visiting all constrained facets of the triangulation.

The value type of this iterator is Triangulation::Facet.

Constrained_facets_range

template<typename Traits , typename Tr = CGAL::Default>

using CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::Constrained_facets_range = CGAL::Iterator_range<Constrained_facets_iterator>

defines a range type for iterating over the constrained facets.

This type is used to iterate through all facets that are constrained. Its iterator type is Constrained_facets_iterator.

Constructor & Destructor Documentation

Conforming_constrained_Delaunay_triangulation_3()

template<typename Traits , typename Tr = CGAL::Default>

CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::Conforming_constrained_Delaunay_triangulation_3

(

)

Default constructor.

This constructor initializes an empty Conforming_constrained_Delaunay_triangulation_3 object.

Member Function Documentation

constrained_facets()

template<typename Traits , typename Tr = CGAL::Default>

Constrained_facets_range CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::constrained_facets

(

)

const

returns a range of the constrained facets.

Its iterator type is Constrained_facets_iterator

constrained_facets_begin()

template<typename Traits , typename Tr = CGAL::Default>

Constrained_facets_iterator CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::constrained_facets_begin

(

)

const

returns an iterator to the start of the sequence of constrained facets.

This function provides an iterator to the first facet that is constrained within the triangulation. The sequence of constrained facets is in an arbitrary order.

face_constraint_index() [1/2]

template<typename Traits , typename Tr = CGAL::Default>

CDT_3_signed_index CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::face_constraint_index

(

const typename Triangulation::Facet &

f

)

const

returns the index of the constraint that constrains the facet f

Precondition

is_facet_constrained(f)

face_constraint_index() [2/2]

template<typename Traits , typename Tr = CGAL::Default>

CDT_3_signed_index CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::face_constraint_index	(	typename Triangulation::Cell_handle	ch,
		int	i
	)		const

same as face_constraint_index(f) with f being Triangulation::Facet(ch, index).

Precondition

is_facet_constrained(f)

is_facet_constrained()

template<typename Traits , typename Tr = CGAL::Default>

bool CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::is_facet_constrained

(

const typename Triangulation::Facet &

f

)

const

returns whether a facet is constrained or not.

Parameters

f	is a facet of the triangulation, of type Triangulation::Facet, as defined by its triangulation data structure.

is_valid()

template<typename Traits , typename Tr = CGAL::Default>

bool CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::is_valid

(

bool

verbose = false

)

const

returns whether the triangulation is valid.

When verbose is set to true, messages describing the first invalidity encountered are printed.

triangulation() [1/2]

template<typename Traits , typename Tr = CGAL::Default>

Triangulation CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::triangulation

(

)

&&

moves and returns the underlying triangulation, then clears the object.

This function allows the underlying triangulation to be moved out of this object.

Example usage:

  auto tr = std::move(ccdt).triangulation();
  // Now `tr` is a valid `CGAL::Triangulation_3` object that can be used for further processing.
  // and the triangulation of `ccdt` is empty.
  std::cout << "Number of vertices in the triangulation `tr`: "
            << tr.number_of_vertices() << '\n';
  std::cout << "Number of vertices in `ccdt`: "
            << ccdt.triangulation().number_of_vertices() << '\n';
  assert(ccdt.triangulation().number_of_vertices() == 0);

After calling this function, ccdt will be empty and tr will be move-constructed from the underlying triangulation, avoiding any copy.

Note

This function is available only when the object is an rvalue.

Postcondition

After this function is called, the object is in a state equivalent to that of a default-constructed object.

triangulation() [2/2]

template<typename Traits , typename Tr = CGAL::Default>

const Triangulation & CGAL::Conforming_constrained_Delaunay_triangulation_3< Traits, Tr >::triangulation

(

)

const &

returns a const reference to the underlying triangulation.

This allows the use of all non-modifying functions of the base triangulation. See the other overload for a way to move the triangulation out of this object and then modify it.

Example usage:

  std::cout << "Number of vertices in the CDT: "
            << ccdt.triangulation().number_of_vertices() << '\n';