CGAL 5.6.1 - CGAL and the Boost Graph Library

Several functions to enlarge or reduce a k-ring selection of vertices, edges, or faces.

Functions

template<class FaceRange , class FaceGraph , class IsFaceSelectedPMap , class OutputIterator >
OutputIterator CGAL::expand_face_selection (const FaceRange &selection, FaceGraph &fg, unsigned int k, IsFaceSelectedPMap is_selected, OutputIterator out)
 augments a selection with faces of fg that are adjacent to a face in selection. More...
 
template<class FaceRange , class FaceGraph , class IsFaceSelectedPMap , class OutputIterator >
OutputIterator CGAL::reduce_face_selection (const FaceRange &selection, FaceGraph &fg, unsigned int k, IsFaceSelectedPMap is_selected, OutputIterator out)
 diminishes a selection of faces from faces adjacent to a non-selected face. More...
 
template<typename TriangleMesh , typename IsSelectedMap , typename NamedParameters = parameters::Default_named_parameters>
void CGAL::regularize_face_selection_borders (TriangleMesh &mesh, IsSelectedMap is_selected, double weight, const NamedParameters &np=parameters::default_values())
 regularizes a selection in order to minimize the length of the border of the selection. More...
 
template<class HalfedgeRange , class FaceGraph , class OutputIterator >
OutputIterator CGAL::select_incident_faces (const HalfedgeRange &hedges, FaceGraph &fg, OutputIterator out)
 Discovers and puts in out all faces incident to the target vertex of a halfedge in hedges. More...
 
template<class EdgeRange , class HalfedgeGraph , class IsEdgeSelectedPMap , class OutputIterator >
OutputIterator CGAL::expand_edge_selection (const EdgeRange &selection, HalfedgeGraph &fg, unsigned int k, IsEdgeSelectedPMap is_selected, OutputIterator out)
 augments a selection with edges of fg that are adjacent to an edge in selection. More...
 
template<class EdgeRange , class HalfedgeGraph , class IsEdgeSelectedPMap , class OutputIterator >
OutputIterator CGAL::reduce_edge_selection (const EdgeRange &selection, HalfedgeGraph &fg, unsigned int k, IsEdgeSelectedPMap is_selected, OutputIterator out)
 diminishes a selection of edges from edges adjacent to a non-selected edge. More...
 
template<class VertexRange , class HalfedgeGraph , class IsVertexSelectedPMap , class OutputIterator >
OutputIterator CGAL::expand_vertex_selection (const VertexRange &selection, HalfedgeGraph &fg, unsigned int k, IsVertexSelectedPMap is_selected, OutputIterator out)
 augments a selection with vertices of fg that are adjacent to a vertex in selection. More...
 
template<class VertexRange , class HalfedgeGraph , class IsVertexSelectedPMap , class OutputIterator >
OutputIterator CGAL::reduce_vertex_selection (const VertexRange &selection, HalfedgeGraph &fg, unsigned int k, IsVertexSelectedPMap is_selected, OutputIterator out)
 diminishes a selection of vertices from vertices adjacent to a non-selected vertex. More...
 
template<class TriangleMesh , class FaceRange , class IsSelectedMap >
void CGAL::expand_face_selection_for_removal (const FaceRange &faces_to_be_deleted, TriangleMesh &tm, IsSelectedMap is_selected)
 Expands a selection of faces so that their removal does not create any non manifold vertex. More...
 

Function Documentation

◆ expand_edge_selection()

template<class EdgeRange , class HalfedgeGraph , class IsEdgeSelectedPMap , class OutputIterator >
OutputIterator CGAL::expand_edge_selection ( const EdgeRange &  selection,
HalfedgeGraph fg,
unsigned int  k,
IsEdgeSelectedPMap  is_selected,
OutputIterator  out 
)

#include <CGAL/boost/graph/selection.h>

augments a selection with edges of fg that are adjacent to an edge in selection.

This process is applied k times considering all edges added in the previous steps. Two edges are said to be adjacent if they are incident to the same face or vertex. Each new edge added in the selection is added exactly once in out.

Template Parameters
EdgeRangea range of edge descriptors, model of Range. Its iterator type is InputIterator.
FaceGrapha model of FaceGraph.
IsEdgeSelectedPMapa model of ReadWritePropertyMap with boost::graph_traits<FaceGraph>::edge_descriptor as key type and bool as value type.
OutputIteratoran output iterator accepting edge descriptors.
Parameters
selectionthe initial selection of edges that will be expanded.
fgthe graph containing the selected edges.
kthe number of times the expansion procedure is iteratively applied.
is_selectedindicates if an edge is part of the selection. It is updated by the function to accommodate new edges added to the selection.
outnew edges added to the selection are added exactly once in out.

◆ expand_face_selection()

template<class FaceRange , class FaceGraph , class IsFaceSelectedPMap , class OutputIterator >
OutputIterator CGAL::expand_face_selection ( const FaceRange &  selection,
FaceGraph fg,
unsigned int  k,
IsFaceSelectedPMap  is_selected,
OutputIterator  out 
)

#include <CGAL/boost/graph/selection.h>

augments a selection with faces of fg that are adjacent to a face in selection.

This process is applied k times considering all faces added in the previous steps. Two faces are said to be adjacent if they share a vertex or an edge. Each new face added in the selection is added exactly once in out.

Template Parameters
FaceRangea range of face descriptors, model of Range. Its iterator type is InputIterator.
FaceGrapha model of FaceGraph.
IsFaceSelectedPMapa model of ReadWritePropertyMap with boost::graph_traits<FaceGraph>::face_descriptor as key type and bool as value type.
OutputIteratoran output iterator accepting face descriptors.
Parameters
selectionthe initial selection of faces that will be expanded.
fgthe graph containing the selected faces.
kthe number of times the expansion procedure is iteratively applied.
is_selectedindicates if a face is part of the selection. It is updated by the function to accommodate new faces added to the selection.
outnew faces added to the selection are added exactly once in out.

◆ expand_face_selection_for_removal()

template<class TriangleMesh , class FaceRange , class IsSelectedMap >
void CGAL::expand_face_selection_for_removal ( const FaceRange &  faces_to_be_deleted,
TriangleMesh &  tm,
IsSelectedMap  is_selected 
)

#include <CGAL/boost/graph/selection.h>

Expands a selection of faces so that their removal does not create any non manifold vertex.

For each vertex that is incident to a selected face, we turn around that vertex and check if there is exactly one set of consecutive selected faces. If not, additional faces around that vertex are selected to match this condition.

Template Parameters
TriangleMesha model of FaceGraph that is triangulated.
FaceRangea range of boost::graph_traits<TriangleMesh>::face_descriptor, with an iterator type model of ForwardIterator.
IsSelectedMapa model of ReadWritePropertyMap with boost::graph_traits<TriangleMesh>::face_descriptor as key and bool as value.
Parameters
tmthe triangle mesh.
faces_to_be_deletedthe range of selected faces.
is_selecteda property map containing the selected-or-not status of each face of tm. It must associate true to each face of faces_to_be_deleted and false to any other face of tm. It will be modified if the face selection must be expanded.

◆ expand_vertex_selection()

template<class VertexRange , class HalfedgeGraph , class IsVertexSelectedPMap , class OutputIterator >
OutputIterator CGAL::expand_vertex_selection ( const VertexRange &  selection,
HalfedgeGraph fg,
unsigned int  k,
IsVertexSelectedPMap  is_selected,
OutputIterator  out 
)

#include <CGAL/boost/graph/selection.h>

augments a selection with vertices of fg that are adjacent to a vertex in selection.

This process is applied k times considering all vertices added in the previous steps. Two vertices are said to be adjacent if they are part of the same face. Each new vertex added in the selection is added exactly once in out.

Template Parameters
VertexRangea range of vertex descriptors, model of Range. Its iterator type is InputIterator.
FaceGrapha model of FaceGraph.
IsVertexSelectedPMapa model of ReadWritePropertyMap with boost::graph_traits<FaceGraph>::vertex_descriptor as key type and bool as value type.
OutputIteratoran output iterator accepting vertex descriptors.
Parameters
selectionthe initial selection of vertices that will be expanded.
fgthe graph containing the selected vertices.
kthe number of times the expansion procedure is iteratively applied.
is_selectedindicates if a vertex is part of the selection. It is updated by the function to accommodate new vertices added to the selection.
outnew vertices added to the selection are added exactly once in out.

◆ reduce_edge_selection()

template<class EdgeRange , class HalfedgeGraph , class IsEdgeSelectedPMap , class OutputIterator >
OutputIterator CGAL::reduce_edge_selection ( const EdgeRange &  selection,
HalfedgeGraph fg,
unsigned int  k,
IsEdgeSelectedPMap  is_selected,
OutputIterator  out 
)

#include <CGAL/boost/graph/selection.h>

diminishes a selection of edges from edges adjacent to a non-selected edge.

This process is applied k times considering all edges removed in the previous steps. Two edges are said to be adjacent if they are incident to the same face or vertex. Each edge removed from the selection is added exactly once in out.

Template Parameters
EdgeRangea range of edge descriptors, model of Range. Its iterator type is InputIterator.
FaceGrapha model of FaceGraph.
IsEdgeSelectedPMapa model of ReadWritePropertyMap with boost::graph_traits<FaceGraph>::edge_descriptor as key type and bool as value type.
OutputIteratoran output iterator accepting edge descriptors.
Parameters
selectionthe initial selection of edges that will be reduced.
fgthe graph containing the selected edges.
kthe number of times the reduction procedure is iteratively applied.
is_selectedindicates if an edge is part of the selection. It is updated by the function to accommodate edges removed from the selection.
outedges removed from the selection are added exactly once in out.

◆ reduce_face_selection()

template<class FaceRange , class FaceGraph , class IsFaceSelectedPMap , class OutputIterator >
OutputIterator CGAL::reduce_face_selection ( const FaceRange &  selection,
FaceGraph fg,
unsigned int  k,
IsFaceSelectedPMap  is_selected,
OutputIterator  out 
)

#include <CGAL/boost/graph/selection.h>

diminishes a selection of faces from faces adjacent to a non-selected face.

This process is applied k times considering all faces removed in the previous steps. Two faces are said to be adjacent if they share a vertex or an edge. Each face removed from the selection is added exactly once in out.

Template Parameters
FaceRangea range of face descriptors, model of Range. Its iterator type is InputIterator.
FaceGrapha model of FaceGraph.
IsFaceSelectedPMapa model of ReadWritePropertyMap with boost::graph_traits<FaceGraph>::face_descriptor as key type and bool as value type.
OutputIteratoran output iterator accepting face descriptors.
Parameters
selectionthe initial selection of faces that will be expanded.
fgthe graph containing the selected faces.
kthe number of times the reduction procedure is iteratively applied.
is_selectedindicates if a face is part of the selection. It is updated by the function to accommodate faces removed from the selection.
outfaces removed from the selection are added exactly once in out.

update is-selected attribute and output iterator

◆ reduce_vertex_selection()

template<class VertexRange , class HalfedgeGraph , class IsVertexSelectedPMap , class OutputIterator >
OutputIterator CGAL::reduce_vertex_selection ( const VertexRange &  selection,
HalfedgeGraph fg,
unsigned int  k,
IsVertexSelectedPMap  is_selected,
OutputIterator  out 
)

#include <CGAL/boost/graph/selection.h>

diminishes a selection of vertices from vertices adjacent to a non-selected vertex.

This process is applied k times considering all vertices removed in the previous steps. Two vertices are said to be adjacent if they are part of the same face. Each vertex removed from the selection is added exactly once in out.

Template Parameters
VertexRangea range of vertex descriptors, model of Range. Its iterator type is InputIterator.
FaceGrapha model of FaceGraph.
IsVertexSelectedPMapa model of ReadWritePropertyMap with boost::graph_traits<FaceGraph>::vertex_descriptor as key type and bool as value type.
OutputIteratoran output iterator accepting vertex descriptors.
Parameters
selectionthe initial selection of vertices that will be reduced.
fgthe graph containing the selected vertices.
kthe number of times the reduction procedure is iteratively applied.
is_selectedindicates if a vertex is part of the selection. It is updated by the function to accommodate vertices removed from the selection.
outvertices removed from the selection are added exactly once in out.

◆ regularize_face_selection_borders()

template<typename TriangleMesh , typename IsSelectedMap , typename NamedParameters = parameters::Default_named_parameters>
void CGAL::regularize_face_selection_borders ( TriangleMesh &  mesh,
IsSelectedMap  is_selected,
double  weight,
const NamedParameters &  np = parameters::default_values() 
)

#include <CGAL/boost/graph/selection.h>

regularizes a selection in order to minimize the length of the border of the selection.

The alpha expansion algorithm is used (see CGAL::alpha_expansion_graphcut()) using the length of the edge between two faces as the edge cost and the initial selected/unselected property of a face as the face cost.

If prevent_unselection is set to true, the cost of unselecting a face is set to infinity, which forces the regularization to only select new faces and ensures that the regularization keeps all selected faces.

Template Parameters
TriangleMesha model of FaceGraph
IsSelectedMapa model of ReadWritePropertyMap with boost::graph_traits<TriangleMesh>::face_descriptor as key type and bool as value type
NamedParametersa sequence of named parameters
Parameters
meshthe mesh containing the selected faces.
is_selectedindicates if a face is part of the selection. It is updated by the function to accommodate faces added or removed from the selection.
weightsets the tradeoff between data fidelity and regularity, ranging from 0 (no regularization at all, selection is left unaltered) to 1 (maximum regularization, usually selects or unselects everything so that the length of the border of the selection is 0)
npan optional sequence of Named Parameters among the ones listed below
Optional Named Parameters
  • a property map associating points to the vertices of tm
  • Type: a class model of ReadWritePropertyMap with boost::graph_traits<TriangleMesh>::vertex_descriptor as key type and Point_3 as value type
  • Default: boost::get(CGAL::vertex_point, tm)
  • Extra: If this parameter is omitted, an internal property map for CGAL::vertex_point_t must be available in TriangleMesh.

  • a property map associating to each face of tm a unique index between 0 and num_faces(tm) - 1
  • Type: a class model of ReadablePropertyMap with boost::graph_traits<TriangleMesh>::face_descriptor as key type and std::size_t as value type
  • Default: an automatically indexed internal map

  • Boolean used to indicate if selection can be only expanded or if it can also be shrunk.
  • Type: bool
  • Default: false
  • Extra: The geometric traits class must be compatible with the vertex point type.

  • an instance of a geometric traits class
  • Type: a class model of Kernel
  • Default: a CGAL Kernel deduced from the point type, using CGAL::Kernel_traits
  • Extra: The geometric traits class must be compatible with the vertex point type.
Examples:
BGL_graphcut/face_selection_borders_regularization_example.cpp.

◆ select_incident_faces()

template<class HalfedgeRange , class FaceGraph , class OutputIterator >
OutputIterator CGAL::select_incident_faces ( const HalfedgeRange &  hedges,
FaceGraph fg,
OutputIterator  out 
)

#include <CGAL/boost/graph/selection.h>

Discovers and puts in out all faces incident to the target vertex of a halfedge in hedges.

Faces are put exactly once in out.

Template Parameters
HalfedgeRangea range of halfedge descriptors, model of Range. Its iterator type is InputIterator.
HalfedgeGrapha model of HalfedgeGraph.
OutputIteratoran output iterator accepting face descriptors.
Parameters
hedgesthe range a halfedge descriptors consider during the face selection.
fgthe graph containing the input halfedges.
outfaces added to the selection are added exactly once in out.