Class that wraps a QgsMesh to ensure the consistency of the mesh during editing and help to access to elements from other elements. More...

#include <qgstopologicalmesh.h>

Classes
class	Changes
	Class that contains topological differences between two states of a topological mesh, only accessible from the QgsTopologicalMesh class. More...

class	TopologicalFaces
	Class that contains independent faces an topological information about this faces. More...

Public Types
using	FaceNeighbors = QVector< int >

Public Member Functions
Changes	addFaces (const TopologicalFaces &topologicFaces)
	Adds faces topologicFaces to the topologic mesh.

Changes	addFreeVertex (const QgsMeshVertex &vertex)
	Adds a free vertex in the face, that is a vertex that is not included or linked with any faces.

Changes	addVertexInFace (int faceIndex, const QgsMeshVertex &vertex)
	Adds a vertex in the face with index faceIndex.

void	applyChanges (const Changes &changes)
	Applies the changes.

bool	canBeMerged (int vertexIndex1, int vertexIndex2) const
	Returns `true` if faces separated by vertices with indexes vertexIndex1 and vertexIndex2 can be merged.

bool	canBeSplit (int faceIndex) const
	Returns `true` if face with index faceIndex can be split.

Changes	changeXYValue (const QList< int > &verticesIndexes, const QList< QgsPointXY > &newValues)
	Changes the (X,Y) values of the vertices with indexes in vertices indexes with the values in newValues.

Changes	changeZValue (const QList< int > &verticesIndexes, const QList< double > &newValues)
	Changes the Z values of the vertices with indexes in vertices indexes with the values in newValues.

QgsMeshEditingError	checkConsistency () const
	Checks the consistency of the topological mesh and return `false` if there is a consistency issue.

bool	delaunayConditionForEdge (int vertexIndex1, int vertexIndex2)
	Check if Delaunay condition holds for given edge returns `true` if delaunay condition holds `false` otherwise.

bool	edgeCanBeFlipped (int vertexIndex1, int vertexIndex2) const
	Returns `true` if the edge can be flipped (only available for edge shared by two faces with 3 vertices)

QList< int >	facesAroundVertex (int vertexIndex) const
	Returns the indexes of faces that are around the vertex with index vertexIndex.

QgsMeshEditingError	facesCanBeAdded (const TopologicalFaces &topologicalFaces) const
	Returns whether the faces can be added to the mesh.

QgsMeshEditingError	facesCanBeRemoved (const QList< int > &facesIndexes)
	Returns whether faces with index in faceIndexes can be removed/ The method an error object with type QgsMeshEditingError::NoError if the faces can be removed, otherwise returns the corresponding error.

int	firstFaceLinked (int vertexIndex) const
	Returns the index of the first face linked, returns -1 if it is a free vertex or out of range index.

Changes	flipEdge (int vertexIndex1, int vertexIndex2)
	Flips edge (vertexIndex1, vertexIndex2) The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

QList< int >	freeVerticesIndexes () const
	Returns a list of vertices are not linked to any faces.

Changes	insertVertexInFacesEdge (int faceIndex, int position, const QgsMeshVertex &vertex)
	Inserts a vertex in the edge of face with index faceIndex at position .

bool	isVertexFree (int vertexIndex) const
	Returns whether the vertex is a free vertex.

bool	isVertexOnBoundary (int vertexIndex) const
	Returns whether the vertex is on a boundary.

Changes	merge (int vertexIndex1, int vertexIndex2)
	Merges faces separated by vertices with indexes vertexIndex1 and vertexIndex2 The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

QgsMesh *	mesh () const
	Returns a pointer to the wrapped mesh.

QVector< int >	neighborsOfFace (int faceIndex) const
	Returns the indexes of neighbor faces of the face with index faceIndex.

void	reindex ()
	Reindexes faces and vertices, after this operation, the topological mesh can't be edited anymore and only the method mesh can be used to access to the raw mesh.

Changes	removeFaces (const QList< int > &facesIndexes)
	Removes faces with index in faceIndexes.

Changes	removeVertexFillHole (int vertexIndex)
	Removes the vertex with index vertexIndex.

Changes	removeVertices (const QList< int > &vertices)
	Removes all the vertices with index in the list vertices If vertices in linked with faces, the operation leads also to remove the faces without filling holes.

bool	renumber ()
	Renumbers the indexes of vertices and faces using the Reverse CutHill McKee Algorithm.

void	reverseChanges (const Changes &changes)
	Reverses the changes.

Changes	splitFace (int faceIndex)
	Splits face with index faceIndex The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

QgsMeshVertexCirculator	vertexCirculator (int vertexIndex) const
	Returns a vertex circulator linked to this mesh around the vertex with index vertexIndex.

Static Public Member Functions
static QgsMeshEditingError	checkTopology (const QgsMesh &mesh, int maxVerticesPerFace)
	Checks the topology of the mesh mesh, if error occurs, this mesh can't be edited.

static QgsMeshEditingError	checkTopologyOfVerticesAsFace (const QVector< QgsMeshVertex > &vertices, bool &clockwise)
	Checks the topology of the vertices as they are contained in a face and returns indication on direction.

static QgsMeshEditingError	counterClockwiseFaces (QgsMeshFace &face, QgsMesh *mesh)
	Checks the topology of the face and sets it counter clockwise if necessary.

static TopologicalFaces	createNewTopologicalFaces (const QVector< QgsMeshFace > &faces, bool uniqueSharedVertexAllowed, QgsMeshEditingError &error)
	Creates new topological faces that are not yet included in the mesh.

static QgsTopologicalMesh	createTopologicalMesh (QgsMesh *mesh, int maxVerticesPerFace, QgsMeshEditingError &error)
	Creates a topologicaly consistent mesh with mesh, this static method modifies mesh to be topological consistent and return a QgsTopologicalMesh instance that contains and handles this mesh (does not take ownership).

static int	vertexPositionInFace (const QgsMesh &mesh, int vertexIndex, int faceIndex)
	Returns vertex position in face.

static int	vertexPositionInFace (int vertexIndex, const QgsMeshFace &face)
	Returns vertex position in face.

Friends
class	QgsMeshVertexCirculator

Detailed Description

Class that wraps a QgsMesh to ensure the consistency of the mesh during editing and help to access to elements from other elements.

A topological face need to:

be convex
counter clock wise
not share an unique vertex with another face

Since: QGIS 3.22

Definition at line 47 of file qgstopologicalmesh.h.

Member Typedef Documentation

◆ FaceNeighbors

using QgsTopologicalMesh::FaceNeighbors = QVector<int>

Definition at line 51 of file qgstopologicalmesh.h.

Member Function Documentation

◆ addFaces()

QgsTopologicalMesh::Changes QgsTopologicalMesh::addFaces ( const TopologicalFaces & topologicFaces )

Adds faces topologicFaces to the topologic mesh.

The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 283 of file qgstopologicalmesh.cpp.

◆ addFreeVertex()

QgsTopologicalMesh::Changes QgsTopologicalMesh::addFreeVertex ( const QgsMeshVertex & vertex )

Adds a free vertex in the face, that is a vertex that is not included or linked with any faces.

The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 1134 of file qgstopologicalmesh.cpp.

◆ addVertexInFace()

QgsTopologicalMesh::Changes QgsTopologicalMesh::addVertexInFace	(	int	faceIndex,
		const QgsMeshVertex &	vertex
	)

Adds a vertex in the face with index faceIndex.

The including face is removed and new faces surrounding the added vertex are added. The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 2296 of file qgstopologicalmesh.cpp.

◆ applyChanges()

void QgsTopologicalMesh::applyChanges ( const Changes & changes )

Applies the changes.

Definition at line 356 of file qgstopologicalmesh.cpp.

◆ canBeMerged()

bool QgsTopologicalMesh::canBeMerged	(	int	vertexIndex1,
		int	vertexIndex2
	)		const

Returns true if faces separated by vertices with indexes vertexIndex1 and vertexIndex2 can be merged.

Definition at line 2076 of file qgstopologicalmesh.cpp.

◆ canBeSplit()

bool QgsTopologicalMesh::canBeSplit ( int faceIndex ) const

Returns true if face with index faceIndex can be split.

Definition at line 2209 of file qgstopologicalmesh.cpp.

◆ changeXYValue()

QgsTopologicalMesh::Changes QgsTopologicalMesh::changeXYValue	(	const QList< int > &	verticesIndexes,
		const QList< QgsPointXY > &	newValues
	)

Changes the (X,Y) values of the vertices with indexes in vertices indexes with the values in newValues.

Definition at line 2565 of file qgstopologicalmesh.cpp.

◆ changeZValue()

QgsTopologicalMesh::Changes QgsTopologicalMesh::changeZValue	(	const QList< int > &	verticesIndexes,
		const QList< double > &	newValues
	)

Changes the Z values of the vertices with indexes in vertices indexes with the values in newValues.

Definition at line 2546 of file qgstopologicalmesh.cpp.

◆ checkConsistency()

QgsMeshEditingError QgsTopologicalMesh::checkConsistency ( ) const

Checks the consistency of the topological mesh and return false if there is a consistency issue.

Definition at line 544 of file qgstopologicalmesh.cpp.

◆ checkTopology()

QgsMeshEditingError QgsTopologicalMesh::checkTopology	(	const QgsMesh &	mesh,
		int	maxVerticesPerFace
	)

static

Checks the topology of the mesh mesh, if error occurs, this mesh can't be edited.

Definition at line 589 of file qgstopologicalmesh.cpp.

◆ checkTopologyOfVerticesAsFace()

QgsMeshEditingError QgsTopologicalMesh::checkTopologyOfVerticesAsFace	(	const QVector< QgsMeshVertex > &	vertices,
		bool &	clockwise
	)

static

Checks the topology of the vertices as they are contained in a face and returns indication on direction.

If the face is clockwise, clockwise is true

Since: QGIS 3.30

Definition at line 635 of file qgstopologicalmesh.cpp.

◆ counterClockwiseFaces()

QgsMeshEditingError QgsTopologicalMesh::counterClockwiseFaces	(	QgsMeshFace &	face,
		QgsMesh *	mesh
	)

static

Checks the topology of the face and sets it counter clockwise if necessary.

Definition at line 678 of file qgstopologicalmesh.cpp.

◆ createNewTopologicalFaces()

QgsTopologicalMesh::TopologicalFaces QgsTopologicalMesh::createNewTopologicalFaces	(	const QVector< QgsMeshFace > &	faces,
		bool	uniqueSharedVertexAllowed,
		QgsMeshEditingError &	error
	)

static

Creates new topological faces that are not yet included in the mesh.

Definition at line 1707 of file qgstopologicalmesh.cpp.

◆ createTopologicalMesh()

QgsTopologicalMesh QgsTopologicalMesh::createTopologicalMesh	(	QgsMesh *	mesh,
		int	maxVerticesPerFace,
		QgsMeshEditingError &	error
	)

static

Creates a topologicaly consistent mesh with mesh, this static method modifies mesh to be topological consistent and return a QgsTopologicalMesh instance that contains and handles this mesh (does not take ownership).

Definition at line 1665 of file qgstopologicalmesh.cpp.

◆ delaunayConditionForEdge()

bool QgsTopologicalMesh::delaunayConditionForEdge	(	int	vertexIndex1,
		int	vertexIndex2
	)

Check if Delaunay condition holds for given edge returns true if delaunay condition holds false otherwise.

Since: QGIS 3.42

Definition at line 2589 of file qgstopologicalmesh.cpp.

◆ edgeCanBeFlipped()

bool QgsTopologicalMesh::edgeCanBeFlipped	(	int	vertexIndex1,
		int	vertexIndex2
	)		const

Returns true if the edge can be flipped (only available for edge shared by two faces with 3 vertices)

Definition at line 1941 of file qgstopologicalmesh.cpp.

◆ facesAroundVertex()

QList< int > QgsTopologicalMesh::facesAroundVertex ( int vertexIndex ) const

Returns the indexes of faces that are around the vertex with index vertexIndex.

Definition at line 1808 of file qgstopologicalmesh.cpp.

◆ facesCanBeAdded()

QgsMeshEditingError QgsTopologicalMesh::facesCanBeAdded ( const TopologicalFaces & topologicalFaces ) const

Returns whether the faces can be added to the mesh.

Definition at line 1525 of file qgstopologicalmesh.cpp.

◆ facesCanBeRemoved()

QgsMeshEditingError QgsTopologicalMesh::facesCanBeRemoved ( const QList< int > & facesIndexes )

Returns whether faces with index in faceIndexes can be removed/ The method an error object with type QgsMeshEditingError::NoError if the faces can be removed, otherwise returns the corresponding error.

Definition at line 1815 of file qgstopologicalmesh.cpp.

◆ firstFaceLinked()

int QgsTopologicalMesh::firstFaceLinked ( int vertexIndex ) const

Returns the index of the first face linked, returns -1 if it is a free vertex or out of range index.

Definition at line 602 of file qgstopologicalmesh.cpp.

◆ flipEdge()

QgsTopologicalMesh::Changes QgsTopologicalMesh::flipEdge	(	int	vertexIndex1,
		int	vertexIndex2
	)

Flips edge (vertexIndex1, vertexIndex2) The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 1982 of file qgstopologicalmesh.cpp.

◆ freeVerticesIndexes()

QList< int > QgsTopologicalMesh::freeVerticesIndexes ( ) const

Returns a list of vertices are not linked to any faces.

Definition at line 630 of file qgstopologicalmesh.cpp.

◆ insertVertexInFacesEdge()

QgsTopologicalMesh::Changes QgsTopologicalMesh::insertVertexInFacesEdge	(	int	faceIndex,
		int	position,
		const QgsMeshVertex &	vertex
	)

Inserts a vertex in the edge of face with index faceIndex at position .

The faces that are on each side of the edge are removed and replaced by new faces constructed by a triangulation.

Definition at line 2359 of file qgstopologicalmesh.cpp.

◆ isVertexFree()

bool QgsTopologicalMesh::isVertexFree ( int vertexIndex ) const

Returns whether the vertex is a free vertex.

Definition at line 619 of file qgstopologicalmesh.cpp.

◆ isVertexOnBoundary()

bool QgsTopologicalMesh::isVertexOnBoundary ( int vertexIndex ) const

Returns whether the vertex is on a boundary.

Definition at line 609 of file qgstopologicalmesh.cpp.

◆ merge()

QgsTopologicalMesh::Changes QgsTopologicalMesh::merge	(	int	vertexIndex1,
		int	vertexIndex2
	)

Merges faces separated by vertices with indexes vertexIndex1 and vertexIndex2 The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 2119 of file qgstopologicalmesh.cpp.

◆ mesh()

QgsMesh * QgsTopologicalMesh::mesh ( ) const

Returns a pointer to the wrapped mesh.

Definition at line 597 of file qgstopologicalmesh.cpp.

◆ neighborsOfFace()

QVector< int > QgsTopologicalMesh::neighborsOfFace ( int faceIndex ) const

Returns the indexes of neighbor faces of the face with index faceIndex.

Definition at line 1803 of file qgstopologicalmesh.cpp.

◆ reindex()

void QgsTopologicalMesh::reindex ( )

Reindexes faces and vertices, after this operation, the topological mesh can't be edited anymore and only the method mesh can be used to access to the raw mesh.

Definition at line 715 of file qgstopologicalmesh.cpp.

◆ removeFaces()

QgsTopologicalMesh::Changes QgsTopologicalMesh::removeFaces ( const QList< int > & facesIndexes )

Removes faces with index in faceIndexes.

The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 1834 of file qgstopologicalmesh.cpp.

◆ removeVertexFillHole()

QgsTopologicalMesh::Changes QgsTopologicalMesh::removeVertexFillHole ( int vertexIndex )

Removes the vertex with index vertexIndex.

If the vertex in linked with faces, the operation leads also to remove the faces. In this case, the hole is filled by a triangulation. The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 1179 of file qgstopologicalmesh.cpp.

◆ removeVertices()

QgsTopologicalMesh::Changes QgsTopologicalMesh::removeVertices ( const QList< int > & vertices )

Removes all the vertices with index in the list vertices If vertices in linked with faces, the operation leads also to remove the faces without filling holes.

The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 1495 of file qgstopologicalmesh.cpp.

◆ renumber()

bool QgsTopologicalMesh::renumber ( )

Renumbers the indexes of vertices and faces using the Reverse CutHill McKee Algorithm.

Definition at line 765 of file qgstopologicalmesh.cpp.

◆ reverseChanges()

void QgsTopologicalMesh::reverseChanges ( const Changes & changes )

Reverses the changes.

Definition at line 438 of file qgstopologicalmesh.cpp.

◆ splitFace()

QgsTopologicalMesh::Changes QgsTopologicalMesh::splitFace ( int faceIndex )

Splits face with index faceIndex The method returns a instance of the class QgsTopologicalMesh::Change that can be used to reverse or reapply the operation.

Definition at line 2216 of file qgstopologicalmesh.cpp.

◆ vertexCirculator()

QgsMeshVertexCirculator QgsTopologicalMesh::vertexCirculator ( int vertexIndex ) const

Returns a vertex circulator linked to this mesh around the vertex with index vertexIndex.

Definition at line 512 of file qgstopologicalmesh.cpp.

◆ vertexPositionInFace() [1/2]

int QgsTopologicalMesh::vertexPositionInFace	(	const QgsMesh &	mesh,
		int	vertexIndex,
		int	faceIndex
	)

static

Returns vertex position in face.

Definition at line 28 of file qgstopologicalmesh.cpp.

◆ vertexPositionInFace() [2/2]

static int QgsTopologicalMesh::vertexPositionInFace	(	int	vertexIndex,
		const QgsMeshFace &	face
	)

inlinestatic

Returns vertex position in face.

Definition at line 343 of file qgstopologicalmesh.h.

Friends And Related Symbol Documentation

◆ QgsMeshVertexCirculator

friend class QgsMeshVertexCirculator

friend

Definition at line 393 of file qgstopologicalmesh.h.

The documentation for this class was generated from the following files:

/build/qgis-3.41.0+git20250116+d2aaa9c6e02+99sid/src/core/mesh/qgstopologicalmesh.h
/build/qgis-3.41.0+git20250116+d2aaa9c6e02+99sid/src/core/mesh/qgstopologicalmesh.cpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Friends

Detailed Description

Member Typedef Documentation

◆ FaceNeighbors

Member Function Documentation

◆ addFaces()

◆ addFreeVertex()

◆ addVertexInFace()

◆ applyChanges()

◆ canBeMerged()

◆ canBeSplit()

◆ changeXYValue()

◆ changeZValue()

◆ checkConsistency()

◆ checkTopology()

◆ checkTopologyOfVerticesAsFace()

◆ counterClockwiseFaces()

◆ createNewTopologicalFaces()

◆ createTopologicalMesh()

◆ delaunayConditionForEdge()

◆ edgeCanBeFlipped()

◆ facesAroundVertex()

◆ facesCanBeAdded()

◆ facesCanBeRemoved()

◆ firstFaceLinked()

◆ flipEdge()

◆ freeVerticesIndexes()

◆ insertVertexInFacesEdge()

◆ isVertexFree()

◆ isVertexOnBoundary()

◆ merge()

◆ mesh()

◆ neighborsOfFace()

◆ reindex()

◆ removeFaces()

◆ removeVertexFillHole()

◆ removeVertices()

◆ renumber()

◆ reverseChanges()

◆ splitFace()

◆ vertexCirculator()

◆ vertexPositionInFace() [1/2]

◆ vertexPositionInFace() [2/2]

Friends And Related Symbol Documentation

◆ QgsMeshVertexCirculator