DualEdgeTriangulation is an implementation of a triangulation class based on the dual edge data structure. More...

#include <qgsdualedgetriangulation.h>

Inheritance diagram for QgsDualEdgeTriangulation:

Public Member Functions
	QgsDualEdgeTriangulation ()

	QgsDualEdgeTriangulation (const QgsDualEdgeTriangulation &)=delete

	QgsDualEdgeTriangulation (int nop)
	Constructor with a number of points to reserve.

	~QgsDualEdgeTriangulation () override

void	addLine (const QVector< QgsPoint > &points, QgsInterpolator::SourceType lineType) override
	Adds a line (e.g.

int	addPoint (const QgsPoint &p) override
	Adds a point to the triangulation.

bool	calcNormal (double x, double y, QgsPoint &result) override
	Calculates the normal at a point on the surface.

bool	calcPoint (double x, double y, QgsPoint &result) override
	Calculates x-, y and z-value of the point on the surface and assigns it to 'result'.

void	eliminateHorizontalTriangles () override
	Eliminates the horizontal triangles by swapping or by insertion of new points.

QgsDualEdgeTriangulation &	operator= (const QgsDualEdgeTriangulation &other)=delete

int	oppositePoint (int p1, int p2) override
	Returns the number of the point opposite to the triangle points p1, p2 (which have to be on a halfedge).

void	performConsistencyTest () override
	Performs a consistency check, remove this later.

QgsPoint *	point (int i) const override
	Draws the points, edges and the forced lines.

bool	pointInside (double x, double y) override
	Returns `true`, if the point with coordinates x and y is inside the convex hull and `false` otherwise.

QList< int >	pointsAroundEdge (double x, double y) override
	Returns a value list with the numbers of the four points, which would be affected by an edge swap. This function is e.g. needed by NormVecDecorator to know the points, for which the normals have to be recalculated. The returned ValueList has to be deleted by the code which calls the method.

int	pointsCount () const override
	Returns the number of points.

void	ruppertRefinement () override
	Adds points to make the triangles better shaped (algorithm of ruppert)

bool	saveTriangulation (QgsFeatureSink sink, QgsFeedback feedback=nullptr) const override
	Saves the triangulation features to a feature sink.

void	setForcedCrossBehavior (QgsTriangulation::ForcedCrossBehavior b) override
	Sets the behavior of the triangulation in case of crossing forced lines.

void	setTriangleInterpolator (TriangleInterpolator *interpolator) override
	Sets an interpolator object.

QList< int >	surroundingTriangles (int pointno) override
	Returns a value list with the information of the triangles surrounding (counterclockwise) a point.

bool	swapEdge (double x, double y) override
	Swaps the edge which is closest to the point with x and y coordinates (if this is possible)

bool	triangleVertices (double x, double y, QgsPoint &p1, int &n1, QgsPoint &p2, int &n2, QgsPoint &p3, int &n3) override
	Finds out in which triangle the point with coordinates x and y is and assigns the numbers of the vertices to 'n1', 'n2' and 'n3' and the vertices to 'p1', 'p2' and 'p3'.

bool	triangleVertices (double x, double y, QgsPoint &p1, QgsPoint &p2, QgsPoint &p3) override
	Finds out, in which triangle the point with coordinates x and y is and assigns the points at the vertices to 'p1', 'p2' and 'p3.

virtual QgsMesh	triangulationToMesh (QgsFeedback *feedback=nullptr) const override
	Returns a QgsMesh corresponding to the triangulation.

double	xMax () const override
	Returns the largest x-coordinate value of the bounding box.

double	xMin () const override
	Returns the smallest x-coordinate value of the bounding box.

double	yMax () const override
	Returns the largest y-coordinate value of the bounding box.

double	yMin () const override
	Returns the smallest x-coordinate value of the bounding box.

Public Member Functions inherited from QgsTriangulation
virtual	~QgsTriangulation ()=default

Friends
class	TestQgsInterpolator

Additional Inherited Members
Public Types inherited from QgsTriangulation
enum	ForcedCrossBehavior { SnappingTypeVertex , DeleteFirst , InsertVertex }
	Enumeration describing the behavior, if two forced lines cross. More...

Static Public Member Functions inherited from QgsTriangulation
static QgsFields	triangulationFields ()
	Returns the fields output by features when calling saveTriangulation().

Detailed Description

DualEdgeTriangulation is an implementation of a triangulation class based on the dual edge data structure.

Note: Not available in Python bindings.

Since: QGIS 3.16

Definition at line 49 of file qgsdualedgetriangulation.h.

Constructor & Destructor Documentation

◆ QgsDualEdgeTriangulation() [1/3]

QgsDualEdgeTriangulation::QgsDualEdgeTriangulation ( )

inline

Definition at line 187 of file qgsdualedgetriangulation.h.

◆ QgsDualEdgeTriangulation() [2/3]

QgsDualEdgeTriangulation::QgsDualEdgeTriangulation ( const QgsDualEdgeTriangulation & )

delete

◆ QgsDualEdgeTriangulation() [3/3]

QgsDualEdgeTriangulation::QgsDualEdgeTriangulation ( int nop )

inline

Constructor with a number of points to reserve.

Definition at line 193 of file qgsdualedgetriangulation.h.

◆ ~QgsDualEdgeTriangulation()

QgsDualEdgeTriangulation::~QgsDualEdgeTriangulation ( )

override

Definition at line 50 of file qgsdualedgetriangulation.cpp.

Member Function Documentation

◆ addLine()

void QgsDualEdgeTriangulation::addLine	(	const QVector< QgsPoint > &	points,
		QgsInterpolator::SourceType	lineType
	)

overridevirtual

Adds a line (e.g.

a break-, structure- or an isoline) to the triangulation, by specifying a list of source points.

Implements QgsTriangulation.

Definition at line 76 of file qgsdualedgetriangulation.cpp.

◆ addPoint()

int QgsDualEdgeTriangulation::addPoint ( const QgsPoint & point )

overridevirtual

Adds a point to the triangulation.

The point should have a z-value matching the value to interpolate.

Implements QgsTriangulation.

Definition at line 108 of file qgsdualedgetriangulation.cpp.

◆ calcNormal()

bool QgsDualEdgeTriangulation::calcNormal	(	double	x,
		double	y,
		QgsPoint &	result
	)

overridevirtual

Calculates the normal at a point on the surface.

Implements QgsTriangulation.

Definition at line 741 of file qgsdualedgetriangulation.cpp.

◆ calcPoint()

bool QgsDualEdgeTriangulation::calcPoint	(	double	x,
		double	y,
		QgsPoint &	result
	)

overridevirtual

Calculates x-, y and z-value of the point on the surface and assigns it to 'result'.

Returns true in case of success and false in case of failure

Implements QgsTriangulation.

Definition at line 754 of file qgsdualedgetriangulation.cpp.

◆ eliminateHorizontalTriangles()

void QgsDualEdgeTriangulation::eliminateHorizontalTriangles ( )

overridevirtual

Eliminates the horizontal triangles by swapping or by insertion of new points.

Implements QgsTriangulation.

Definition at line 1755 of file qgsdualedgetriangulation.cpp.

◆ operator=()

QgsDualEdgeTriangulation & QgsDualEdgeTriangulation::operator= ( const QgsDualEdgeTriangulation & other )

delete

◆ oppositePoint()

int QgsDualEdgeTriangulation::oppositePoint	(	int	p1,
		int	p2
	)

overridevirtual

Returns the number of the point opposite to the triangle points p1, p2 (which have to be on a halfedge).

Returns -1 if point is a virtual point. Returns -10 if point crosses over edges.

Implements QgsTriangulation.

Definition at line 1031 of file qgsdualedgetriangulation.cpp.

◆ performConsistencyTest()

void QgsDualEdgeTriangulation::performConsistencyTest ( )

overridevirtual

Performs a consistency check, remove this later.

Implements QgsTriangulation.

Definition at line 56 of file qgsdualedgetriangulation.cpp.

◆ point()

QgsPoint * QgsDualEdgeTriangulation::point ( int i ) const

inlineoverridevirtual

Draws the points, edges and the forced lines.

Returns a pointer to the point with number i

Implements QgsTriangulation.

Definition at line 204 of file qgsdualedgetriangulation.h.

◆ pointInside()

bool QgsDualEdgeTriangulation::pointInside	(	double	x,
		double	y
	)

overridevirtual

Returns true, if the point with coordinates x and y is inside the convex hull and false otherwise.

Implements QgsTriangulation.

Definition at line 2708 of file qgsdualedgetriangulation.cpp.

◆ pointsAroundEdge()

QList< int > QgsDualEdgeTriangulation::pointsAroundEdge	(	double	x,
		double	y
	)

overridevirtual

Returns a value list with the numbers of the four points, which would be affected by an edge swap. This function is e.g. needed by NormVecDecorator to know the points, for which the normals have to be recalculated. The returned ValueList has to be deleted by the code which calls the method.

Implements QgsTriangulation.

Definition at line 3127 of file qgsdualedgetriangulation.cpp.

◆ pointsCount()

int QgsDualEdgeTriangulation::pointsCount ( ) const

inlineoverridevirtual

Returns the number of points.

Implements QgsTriangulation.

Definition at line 199 of file qgsdualedgetriangulation.h.

◆ ruppertRefinement()

void QgsDualEdgeTriangulation::ruppertRefinement ( )

overridevirtual

Adds points to make the triangles better shaped (algorithm of ruppert)

Implements QgsTriangulation.

Definition at line 1844 of file qgsdualedgetriangulation.cpp.

◆ saveTriangulation()

bool QgsDualEdgeTriangulation::saveTriangulation	(	QgsFeatureSink *	sink,
		QgsFeedback *	feedback = `nullptr`
	)		const

overridevirtual

Saves the triangulation features to a feature sink.

The sink must be setup to accept LineString features, with fields matching those returned by triangulationFields().

Returns: true in case of success

See also: triangulationFields()

Implements QgsTriangulation.

Definition at line 3185 of file qgsdualedgetriangulation.cpp.

◆ setForcedCrossBehavior()

void QgsDualEdgeTriangulation::setForcedCrossBehavior ( QgsTriangulation::ForcedCrossBehavior b )

overridevirtual

Sets the behavior of the triangulation in case of crossing forced lines.

Implements QgsTriangulation.

Definition at line 1745 of file qgsdualedgetriangulation.cpp.

◆ setTriangleInterpolator()

void QgsDualEdgeTriangulation::setTriangleInterpolator ( TriangleInterpolator * interpolator )

overridevirtual

Sets an interpolator object.

Implements QgsTriangulation.

Definition at line 1750 of file qgsdualedgetriangulation.cpp.

◆ surroundingTriangles()

QList< int > QgsDualEdgeTriangulation::surroundingTriangles ( int pointno )

overridevirtual

Returns a value list with the information of the triangles surrounding (counterclockwise) a point.

Four integer values describe a triangle, the first three are the number of the half edges of the triangle and the fourth is -10, if the third (and most counterclockwise) edge is a breakline, and -20 otherwise. Any virtual point needs to have the number -1

Implements QgsTriangulation.

Definition at line 1065 of file qgsdualedgetriangulation.cpp.

◆ swapEdge()

bool QgsDualEdgeTriangulation::swapEdge	(	double	x,
		double	y
	)

overridevirtual

Swaps the edge which is closest to the point with x and y coordinates (if this is possible)

Implements QgsTriangulation.

Definition at line 3066 of file qgsdualedgetriangulation.cpp.

◆ triangleVertices() [1/2]

bool QgsDualEdgeTriangulation::triangleVertices	(	double	x,
		double	y,
		QgsPoint &	p1,
		int &	n1,
		QgsPoint &	p2,
		int &	n2,
		QgsPoint &	p3,
		int &	n3
	)

overridevirtual

Finds out in which triangle the point with coordinates x and y is and assigns the numbers of the vertices to 'n1', 'n2' and 'n3' and the vertices to 'p1', 'p2' and 'p3'.

Implements QgsTriangulation.

Definition at line 1101 of file qgsdualedgetriangulation.cpp.

◆ triangleVertices() [2/2]

bool QgsDualEdgeTriangulation::triangleVertices	(	double	x,
		double	y,
		QgsPoint &	p1,
		QgsPoint &	p2,
		QgsPoint &	p3
	)

overridevirtual

Finds out, in which triangle the point with coordinates x and y is and assigns the points at the vertices to 'p1', 'p2' and 'p3.

Implements QgsTriangulation.

Definition at line 1209 of file qgsdualedgetriangulation.cpp.

◆ triangulationToMesh()

QgsMesh QgsDualEdgeTriangulation::triangulationToMesh ( QgsFeedback * feedback = nullptr ) const

overridevirtual

Returns a QgsMesh corresponding to the triangulation.

Since: QGIS 3.16

Implements QgsTriangulation.

Definition at line 3248 of file qgsdualedgetriangulation.cpp.

◆ xMax()

double QgsDualEdgeTriangulation::xMax ( ) const

inlineoverridevirtual

Returns the largest x-coordinate value of the bounding box.

Implements QgsTriangulation.

Definition at line 76 of file qgsdualedgetriangulation.h.

◆ xMin()

double QgsDualEdgeTriangulation::xMin ( ) const

inlineoverridevirtual

Returns the smallest x-coordinate value of the bounding box.

Implements QgsTriangulation.

Definition at line 78 of file qgsdualedgetriangulation.h.

◆ yMax()

double QgsDualEdgeTriangulation::yMax ( ) const

inlineoverridevirtual

Returns the largest y-coordinate value of the bounding box.

Implements QgsTriangulation.

Definition at line 80 of file qgsdualedgetriangulation.h.

◆ yMin()

double QgsDualEdgeTriangulation::yMin ( ) const

inlineoverridevirtual

Returns the smallest x-coordinate value of the bounding box.

Implements QgsTriangulation.

Definition at line 82 of file qgsdualedgetriangulation.h.

Friends And Related Symbol Documentation

◆ TestQgsInterpolator

friend class TestQgsInterpolator

friend

Definition at line 182 of file qgsdualedgetriangulation.h.

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

/build/qgis-3.41.0+git20241119+45a0abf3bec+99sid/src/analysis/interpolation/qgsdualedgetriangulation.h
/build/qgis-3.41.0+git20241119+45a0abf3bec+99sid/src/analysis/interpolation/qgsdualedgetriangulation.cpp

Public Member Functions

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsDualEdgeTriangulation() [1/3]

◆ QgsDualEdgeTriangulation() [2/3]

◆ QgsDualEdgeTriangulation() [3/3]

◆ ~QgsDualEdgeTriangulation()

Member Function Documentation

◆ addLine()

◆ addPoint()

◆ calcNormal()

◆ calcPoint()

◆ eliminateHorizontalTriangles()

◆ operator=()

◆ oppositePoint()

◆ performConsistencyTest()

◆ point()

◆ pointInside()

◆ pointsAroundEdge()

◆ pointsCount()

◆ ruppertRefinement()

◆ saveTriangulation()

◆ setForcedCrossBehavior()

◆ setTriangleInterpolator()

◆ surroundingTriangles()

◆ swapEdge()

◆ triangleVertices() [1/2]

◆ triangleVertices() [2/2]

◆ triangulationToMesh()

◆ xMax()

◆ xMin()

◆ yMax()

◆ yMin()

Friends And Related Symbol Documentation

◆ TestQgsInterpolator