Two faces are in the same connected component if there is a path of adjacent faces such that all edges between two consecutive faces of the path are not marked as constrained.

Functions
template<typename PolygonMesh , typename FaceOutputIterator , typename NamedParameters >
FaceOutputIterator	CGAL::Polygon_mesh_processing::connected_component (typename boost::graph_traits< PolygonMesh >::face_descriptor seed_face, const PolygonMesh &pmesh, FaceOutputIterator out, const NamedParameters &np)
	discovers all the faces in the same connected component as `seed_face` and records them in `out`. More...

template<typename PolygonMesh , typename FaceComponentMap , typename NamedParameters >
boost::property_traits< FaceComponentMap >::value_type	CGAL::Polygon_mesh_processing::connected_components (const PolygonMesh &pmesh, FaceComponentMap fcm, const NamedParameters &np)
	computes for each face the index of the corresponding connected component. More...

template<typename PolygonMesh , typename NamedParameters >
std::size_t	CGAL::Polygon_mesh_processing::keep_largest_connected_components (PolygonMesh &pmesh, std::size_t nb_components_to_keep, const NamedParameters &np)
	removes the small connected components and all isolated vertices. More...

template<typename PolygonMesh , typename ThresholdValueType , typename NamedParameters >
std::size_t	CGAL::Polygon_mesh_processing::keep_large_connected_components (PolygonMesh &pmesh, const ThresholdValueType threshold_value, const NamedParameters &np)
	removes connected components whose size is (strictly) smaller than a given threshold value, where the size of a connected component is computed as the sum of the individual sizes of all the faces of the connected component. More...

template<typename PolygonMesh , typename ComponentRange , typename FaceComponentMap , typename NamedParameters >
void	CGAL::Polygon_mesh_processing::keep_connected_components (PolygonMesh &pmesh, const ComponentRange &components_to_keep, const FaceComponentMap &fcm, const NamedParameters &np)
	keeps the connected components designated by theirs ids in `components_to_keep`, and removes the other connected components as well as all isolated vertices. More...

template<typename PolygonMesh , typename ComponentRange , typename FaceComponentMap , typename NamedParameters >
void	CGAL::Polygon_mesh_processing::remove_connected_components (PolygonMesh &pmesh, const ComponentRange &components_to_remove, const FaceComponentMap &fcm, const NamedParameters &np)
	Removes in `pmesh` the connected components designated by theirs ids in `components_to_remove` as well as all isolated vertices. More...

template<typename PolygonMesh , typename FaceRange , typename NamedParameters >
void	CGAL::Polygon_mesh_processing::remove_connected_components (PolygonMesh &pmesh, const FaceRange &components_to_remove, const NamedParameters &np)
	keeps the connected components not designated by the faces in `components_to_remove`, and removes the other connected components and all isolated vertices. More...

template<typename PolygonMesh , typename FaceRange , typename NamedParameters >
void	CGAL::Polygon_mesh_processing::keep_connected_components (PolygonMesh &pmesh, const FaceRange &components_to_keep, const NamedParameters &np)
	keeps the connected components designated by the faces in `components_to_keep`, and removes the other connected components and all isolated vertices. More...

Function Documentation

◆ connected_component()

template<typename PolygonMesh , typename FaceOutputIterator , typename NamedParameters >

FaceOutputIterator CGAL::Polygon_mesh_processing::connected_component	(	typename boost::graph_traits< PolygonMesh >::face_descriptor	seed_face,
		const PolygonMesh &	pmesh,
		FaceOutputIterator	out,
		const NamedParameters &	np
	)

#include <CGAL/Polygon_mesh_processing/connected_components.h>

discovers all the faces in the same connected component as seed_face and records them in out.

seed_face will also be added in out.

Template Parameters

PolygonMesh	a model of `FaceGraph`
FaceOutputIterator	a model of `OutputIterator` that accepts faces of type `boost::graph_traits<PolygonMesh>::face_descriptor`.
NamedParameters	a sequence of Named Parameters

Parameters

seed_face	a face of `pmesh` from which exploration starts to detect the connected component that contains it
pmesh	the polygon mesh
out	the output iterator that collects faces from the same connected component as `seed_face`
np	optional Named Parameters described below

Named Parameters

edge_is_constrained_map a property map containing the constrained-or-not status of each edge of pmesh

Returns: the output iterator.

Examples:: Polygon_mesh_processing/connected_components_example.cpp.

◆ connected_components()

template<typename PolygonMesh , typename FaceComponentMap , typename NamedParameters >

boost::property_traits<FaceComponentMap>::value_type CGAL::Polygon_mesh_processing::connected_components	(	const PolygonMesh &	pmesh,
		FaceComponentMap	fcm,
		const NamedParameters &	np
	)

#include <CGAL/Polygon_mesh_processing/connected_components.h>

computes for each face the index of the corresponding connected component.

A property map for CGAL::face_index_t must be either available as an internal property map to pmesh or provided as one of the Named Parameters.

Template Parameters

PolygonMesh	a model of `FaceListGraph`
FaceComponentMap	a model of `WritablePropertyMap` with `boost::graph_traits<PolygonMesh>::face_descriptor` as key type and `boost::graph_traits<PolygonMesh>::faces_size_type` as value type.
NamedParameters	a sequence of Named Parameters

Parameters

pmesh	the polygon mesh
fcm	the property map with indices of components associated to faces in `pmesh`
np	optional Named Parameters described below

Named Parameters

edge_is_constrained_map	a property map containing the constrained-or-not status of each edge of `pmesh`
face_index_map	a property map containing the index of each face of `pmesh`

Returns: the number of connected components.

Examples:: Polygon_mesh_processing/connected_components_example.cpp, and Polygon_mesh_processing/face_filtered_graph_example.cpp.

◆ keep_connected_components() [1/2]

template<typename PolygonMesh , typename ComponentRange , typename FaceComponentMap , typename NamedParameters >

void CGAL::Polygon_mesh_processing::keep_connected_components	(	PolygonMesh &	pmesh,
		const ComponentRange &	components_to_keep,
		const FaceComponentMap &	fcm,
		const NamedParameters &	np
	)

#include <CGAL/Polygon_mesh_processing/connected_components.h>

keeps the connected components designated by theirs ids in components_to_keep, and removes the other connected components as well as all isolated vertices.

The connected component id of a face is given by fcm.

Note: If the removal of the connected components makes pmesh a non-manifold surface, then the behavior of this function is undefined.

Property maps for CGAL::vertex_index_t must be either available as internal property map to pmesh or provided as Named Parameters.

Template Parameters

PolygonMesh	a model of `FaceListGraph` and `MutableFaceGraph`
NamedParameters	a sequence of Named Parameters
ComponentRange	a range of ids convertible to `std::size`
FaceComponentMap	a model of `ReadWritePropertyMap` with `boost::graph_traits<PolygonMesh>::face_descriptor` as key type and `boost::graph_traits<PolygonMesh>::faces_size_type` as value type.

Parameters

components_to_keep	the range of ids of connected components to keep
pmesh	the polygon mesh
fcm	the property map with indices of components associated to faces in `pmesh`. After calling this function, the values of `fcm` are undefined.
np	optional Named Parameters described below

Named Parameters

vertex_index_map a property map containing the index of each vertex of pmesh

◆ keep_connected_components() [2/2]

template<typename PolygonMesh , typename FaceRange , typename NamedParameters >

void CGAL::Polygon_mesh_processing::keep_connected_components	(	PolygonMesh &	pmesh,
		const FaceRange &	components_to_keep,
		const NamedParameters &	np
	)

#include <CGAL/Polygon_mesh_processing/connected_components.h>

keeps the connected components designated by the faces in components_to_keep, and removes the other connected components and all isolated vertices.

Property maps for CGAL::face_index_t and CGAL::vertex_index_t must be either available as internal property maps to pmesh or provided as Named Parameters.

Note: If the removal of the connected components makes pmesh a non-manifold surface, then the behavior of this function is undefined.

Template Parameters

PolygonMesh	a model of `FaceListGraph` and `MutableFaceGraph`
NamedParameters	a sequence of Named Parameters
FaceRange	a range of `boost::graph_traits<PolygonMesh>::face_descriptor` indicating the connected components to be kept.

Parameters

pmesh	the polygon mesh
components_to_keep	a face range, including one face or more on each component to be kept
np	optional Named Parameters, amongst those described below

Named Parameters

edge_is_constrained_map	a property map containing the constrained-or-not status of each edge of `pmesh`
face_index_map	a property map containing the index of each face of `pmesh`
vertex_index_map	a property map containing the index of each vertex of `pmesh`

◆ keep_large_connected_components()

template<typename PolygonMesh , typename ThresholdValueType , typename NamedParameters >

std::size_t CGAL::Polygon_mesh_processing::keep_large_connected_components	(	PolygonMesh &	pmesh,
		const ThresholdValueType	threshold_value,
		const NamedParameters &	np
	)

#include <CGAL/Polygon_mesh_processing/connected_components.h>

removes connected components whose size is (strictly) smaller than a given threshold value, where the size of a connected component is computed as the sum of the individual sizes of all the faces of the connected component.

By default, the size of a face is 1 (and thus the size of a connected component is the number of faces it contains), but it is also possible to pass custom sizes, such as the area of the face.

Property maps for CGAL::face_index_t and CGAL::vertex_index_t must be either available as internal property maps to pmesh or provided as Named Parameters.

Template Parameters

PolygonMesh	a model of `FaceListGraph` and `MutableFaceGraph`
ThresholdValueType	the type of the threshold value
NamedParameters	a sequence of Named Parameters

Parameters

pmesh	the polygon mesh
threshold_value	any connected component with a size (strictly) smaller than this value will be discarded
np	optional Named Parameters, amongst those described below

Named Parameters

edge_is_constrained_map	a property map containing the constrained-or-not status of each edge of `pmesh`
face_index_map	a property map containing the index of each face of `pmesh`
vertex_index_map	a property map containing the index of each vertex of `pmesh`
face_size_map	a property map containing a size for each face of `pmesh`. The value type of this property map is chosen by the user, but must be constructible from `0` and support `operator+=()` and comparisons.

Precondition: If a face size property map is passed by the user, ThresholdValueType must be the same type as the value type of the property map. Otherwise, ThresholdValueType must be std::size_t.

Returns: the number of connected components removed (ignoring isolated vertices).

Examples:: Polygon_mesh_processing/connected_components_example.cpp.

◆ keep_largest_connected_components()

template<typename PolygonMesh , typename NamedParameters >

std::size_t CGAL::Polygon_mesh_processing::keep_largest_connected_components	(	PolygonMesh &	pmesh,
		std::size_t	nb_components_to_keep,
		const NamedParameters &	np
	)

#include <CGAL/Polygon_mesh_processing/connected_components.h>

removes the small connected components and all isolated vertices.

Keep the nb_components_to_keep largest connected components, where the size of a connected component is computed as the sum of the individual sizes of all the faces of the connected component. By default, the size of a face is 1 (and thus the size of a connected component is the number of faces it contains), but it is also possible to pass custom sizes, such as the area of the face.

Property maps for CGAL::face_index_t and CGAL::vertex_index_t must be either available as internal property maps to pmesh or provided as Named Parameters.

Template Parameters

PolygonMesh	a model of `FaceListGraph` and `MutableFaceGraph`
NamedParameters	a sequence of Named Parameters

Parameters

pmesh	the polygon mesh
nb_components_to_keep	the number of components to be kept
np	optional Named Parameters, amongst those described below

Named Parameters

edge_is_constrained_map	a property map containing the constrained-or-not status of each edge of `pmesh`
face_index_map	a property map containing the index of each face of `pmesh`
vertex_index_map	a property map containing the index of each vertex of `pmesh`
face_size_map	a property map containing a size for each face of `pmesh`. The value type of this property map is chosen by the user, but must be constructible from `0` and support `operator+=()` and comparisons.

Returns: the number of connected components removed (ignoring isolated vertices).

Examples:: Polygon_mesh_processing/connected_components_example.cpp.

◆ remove_connected_components() [1/2]

template<typename PolygonMesh , typename ComponentRange , typename FaceComponentMap , typename NamedParameters >

void CGAL::Polygon_mesh_processing::remove_connected_components	(	PolygonMesh &	pmesh,
		const ComponentRange &	components_to_remove,
		const FaceComponentMap &	fcm,
		const NamedParameters &	np
	)

#include <CGAL/Polygon_mesh_processing/connected_components.h>

Removes in pmesh the connected components designated by theirs ids in components_to_remove as well as all isolated vertices.

The connected component id of a face is given by fcm.

Note: If the removal of the connected components makes pmesh a non-manifold surface, then the behavior of this function is undefined.

Property maps for CGAL::vertex_index_t must be either available as internal property map to pmesh or provided as Named Parameters.

Template Parameters

PolygonMesh	a model of `FaceListGraph` and `MutableFaceGraph`
NamedParameters	a sequence of Named Parameters
ComponentRange	a range of ids convertible to `std::size`
FaceComponentMap	a model of `ReadWritePropertyMap` with `boost::graph_traits<PolygonMesh>::face_descriptor` as key type and `boost::graph_traits<PolygonMesh>::faces_size_type` as value type.

Parameters

components_to_remove	the range of ids of connected components to remove
pmesh	the polygon mesh
fcm	the property map with indices of components associated to faces in `pmesh`. After calling this function, the values of `fcm` are undefined.
np	optional Named Parameters described below

Named Parameters

vertex_index_map a property map containing the index of each vertex of pmesh

◆ remove_connected_components() [2/2]

template<typename PolygonMesh , typename FaceRange , typename NamedParameters >

void CGAL::Polygon_mesh_processing::remove_connected_components	(	PolygonMesh &	pmesh,
		const FaceRange &	components_to_remove,
		const NamedParameters &	np
	)

#include <CGAL/Polygon_mesh_processing/connected_components.h>

keeps the connected components not designated by the faces in components_to_remove, and removes the other connected components and all isolated vertices.

Property maps for CGAL::face_index_t and CGAL::vertex_index_t must be either available as internal property maps to pmesh or provided as Named Parameters.

Note: If the removal of the connected components makes pmesh a non-manifold surface, then the behavior of this function is undefined.

Template Parameters

PolygonMesh	a model of `FaceListGraph` and `MutableFaceGraph`
NamedParameters	a sequence of Named Parameters
FaceRange	a range of `boost::graph_traits<PolygonMesh>::face_descriptor` indicating the connected components to be removed.

Parameters

components_to_remove	a face range, including one face or more on each component to be removed
pmesh	the polygon mesh
np	optional Named Parameters, amongst those described below

Named Parameters

edge_is_constrained_map	a property map containing the constrained-or-not status of each edge of `pmesh`
face_index_map	a property map containing the index of each face of `pmesh`
vertex_index_map	a property map containing the index of each vertex of `pmesh`

Functions

Function Documentation

◆ connected_component()

◆ connected_components()

◆ keep_connected_components() [1/2]

◆ keep_connected_components() [2/2]

◆ keep_large_connected_components()

◆ keep_largest_connected_components()

◆ remove_connected_components() [1/2]

◆ remove_connected_components() [2/2]