Represents a NURBS (Non-Uniform Rational B-Spline) curve geometry in 2D/3D. More...

#include <qgsnurbscurve.h>

Inheritance diagram for QgsNurbsCurve:

[legend]

Public Member Functions
	QgsNurbsCurve ()
	Constructor for an empty NURBS curve geometry.
	QgsNurbsCurve (const QVector< QgsPoint > &controlPoints, int degree, const QVector< double > &knots, const QVector< double > &weights)
	Constructs a NURBS curve from control points, degree, knot vector and weights.
bool	addMValue (double mValue=0) override
	Adds a measure to the geometry, initialized to a preset value.
void	addToPainterPath (QPainterPath &path) const override
	Adds a curve to a painter path.
bool	addZValue (double zValue=0) override
	Adds a z-dimension to the geometry, initialized to a preset value.
QDomElement	asGml2 (QDomDocument &doc, int precision=17, const QString &ns="gml", QgsAbstractGeometry::AxisOrder axisOrder=QgsAbstractGeometry::AxisOrder::XY) const override
	Returns a GML2 representation of the geometry.
QDomElement	asGml3 (QDomDocument &doc, int precision=17, const QString &ns="gml", QgsAbstractGeometry::AxisOrder axisOrder=QgsAbstractGeometry::AxisOrder::XY) const override
	Returns a GML3 representation of the geometry.
json	asJsonObject (int precision=17) const override
	Returns a json object representation of the geometry.
QString	asKml (int precision=17) const override
	Returns a KML representation of the geometry.
QPolygonF	asQPolygonF () const override
	Returns a QPolygonF representing the points.
QByteArray	asWkb (QgsAbstractGeometry::WkbFlags flags=QgsAbstractGeometry::WkbFlags()) const override
	Returns a WKB representation of the geometry.
QString	asWkt (int precision=17) const override
	Returns a WKT representation of the geometry.
QgsRectangle	boundingBox () const override
	Returns the minimal bounding box for the geometry.
QgsBox3D	boundingBox3D () const override
	Returns the 3D bounding box for the geometry.
bool	boundingBoxIntersects (const QgsBox3D &box3d) const override
	Returns `true` if the bounding box of this geometry intersects with a box3d.
bool	boundingBoxIntersects (const QgsRectangle &rectangle) const override
	Returns `true` if the bounding box of this geometry intersects with a rectangle.
QgsPoint	centroid () const override
	Returns the centroid of the geometry.
void	clear () override
	Clears the geometry, ie reset it to a null geometry.
QgsNurbsCurve *	clone () const override
	Clones the geometry by performing a deep copy.
double	closestSegment (const QgsPoint &pt, QgsPoint &segmentPt, QgsVertexId &vertexAfter, int leftOf=nullptr, double epsilon=4 std::numeric_limits< double >::epsilon()) const override
	Searches for the closest segment of the geometry to a given point.
QVector< QgsPoint >	controlPoints () const
	Returns the control points of the NURBS curve.
QgsAbstractGeometry *	createEmptyWithSameType () const override
	Creates a new geometry with the same class and same WKB type as the original and transfers ownership.
QgsCurve *	curveSubstring (double startDistance, double endDistance) const override
	Returns a new curve representing a substring of this curve.
QgsLineString *	curveToLine (double tolerance=M_PI_2/90, SegmentationToleranceType toleranceType=MaximumAngle) const override
	Returns a new line string geometry corresponding to a segmentized approximation of the curve.
int	degree () const
	Returns the degree of the NURBS curve.
bool	deleteVertex (QgsVertexId position) override
	Deletes a vertex within the geometry.
int	dimension () const override
	Returns the inherent dimension of the geometry.
double	distanceBetweenVertices (QgsVertexId fromVertex, QgsVertexId toVertex) const override
	Returns the distance along the curve between two vertices.
void	draw (QPainter &p) const override
	Draws the geometry using the specified QPainter.
void	drawAsPolygon (QPainter &p) const override
	Draws the curve as a polygon on the specified QPainter.
bool	dropMValue () override
	Drops any measure values which exist in the geometry.
bool	dropZValue () override
	Drops any z-dimensions which exist in the geometry.
QgsPoint	endPoint () const override
	Returns the end point of the curve.
bool	equals (const QgsCurve &other) const override
	Checks whether this curve exactly equals another curve.
QgsPoint	evaluate (double t) const
	Evaluates the NURBS curve at parameter t ∈ [0,1].
void	filterVertices (const std::function< bool(const QgsPoint &)> &filter) override
bool	fromWkb (QgsConstWkbPtr &wkb) override
	Sets the geometry from a WKB string.
bool	fromWkt (const QString &wkt) override
	Sets the geometry from a WKT string.
bool	fuzzyDistanceEqual (const QgsAbstractGeometry &other, double epsilon=1e-8) const override
	Performs fuzzy distance comparison between this geometry and other using an epsilon.
bool	fuzzyEqual (const QgsAbstractGeometry &other, double epsilon=1e-8) const override
	Performs fuzzy comparison between this geometry and other using an epsilon.
QString	geometryType () const override
	Returns a unique string representing the geometry type.
bool	hasCurvedSegments () const override
	Returns `true` if the geometry contains curved segments.
int	indexOf (const QgsPoint &point) const override
	Returns the index of the first vertex matching the given point, or -1 if a matching vertex is not found.
bool	insertVertex (QgsVertexId position, const QgsPoint &vertex) override
	Inserts a vertex into the geometry.
QgsPoint *	interpolatePoint (double distance) const override
	Returns an interpolated point on the curve at the specified distance.
bool	isBezier () const
	Returns `true` if this curve represents a Bézier curve.
bool	isBSpline () const
	Returns `true` if this curve represents a B-spline (non-rational NURBS).
bool	isClosed () const override
	Returns `true` if the curve is closed.
bool	isClosed2D () const override
	Returns true if the curve is closed.
bool	isEmpty () const override
	Returns `true` if the geometry is empty.
bool	isPolyBezier () const
	Returns `true` if this curve represents a poly-Bézier curve.
bool	isRational () const
	Returns `true` if this curve is rational (has non-uniform weights).
bool	isValid (QString &error, Qgis::GeometryValidityFlags flags=Qgis::GeometryValidityFlags()) const override
	Checks validity of the geometry, and returns `true` if the geometry is valid.
QVector< double >	knots () const
	Returns the knot vector of the NURBS curve.
double	length () const override
	Returns the planar, 2-dimensional length of the geometry.
double	mAt (int index) const override
	Returns the m-coordinate of the specified node in the line string.
bool	moveVertex (QgsVertexId position, const QgsPoint &newPos) override
	Moves a vertex within the geometry.
int	numPoints () const override
	Returns the number of points in the curve.
int	partCount () const override
	Returns count of parts contained in the geometry.
bool	pointAt (int node, QgsPoint &point, Qgis::VertexType &type) const override
	Returns the point and vertex id of a point within the curve.
void	points (QgsPointSequence &pts) const override
	Returns a list of points within the curve.
bool	removeDuplicateNodes (double epsilon=4 *std::numeric_limits< double >::epsilon(), bool useZValues=false) override
	Removes duplicate nodes from the geometry, wherever removing the nodes does not result in a degenerate geometry.
QgsCurve *	reversed () const override
	Returns a reversed copy of the curve, where the direction of the curve has been flipped.
void	scroll (int firstVertexIndex) override
	Scrolls the curve vertices so that they start with the vertex at the given index.
double	segmentLength (QgsVertexId startVertex) const override
	Returns the length of the segment of the geometry which begins at startVertex.
void	setControlPoints (const QVector< QgsPoint > &points)
	Sets the control points of the NURBS curve.
void	setDegree (int degree)
	Sets the degree of the NURBS curve.
void	setKnots (const QVector< double > &knots)
	Sets the knot vector of the NURBS curve.
bool	setWeight (int index, double weight)
	Sets the weight at the specified control point index.
void	setWeights (const QVector< double > &weights)
	Sets the weight vector of the NURBS curve.
QgsAbstractGeometry *	simplifyByDistance (double tolerance) const override
	Simplifies the geometry by applying the Douglas Peucker simplification by distance algorithm.
QgsAbstractGeometry *	snappedToGrid (double hSpacing, double vSpacing, double dSpacing=0, double mSpacing=0, bool removeRedundantPoints=false) const override
	Makes a new geometry with all the points or vertices snapped to the closest point of the grid.
std::tuple< std::unique_ptr< QgsCurve >, std::unique_ptr< QgsCurve > >	splitCurveAtVertex (int index) const override
	Splits the curve at the specified vertex index, returning two curves which represent the portion of the curve up to an including the vertex at index, and the portion of the curve from the vertex at index (inclusive) to the end of the curve.
QgsPoint	startPoint () const override
	Returns the starting point of the curve.
void	sumUpArea (double &sum) const override
	Sums up the area of the curve by iterating over the vertices (shoelace formula).
void	sumUpArea3D (double &sum) const override
	Sums up the 3d area of the curve by iterating over the vertices (shoelace formula).
void	swapXy () override
	Swaps the x and y coordinates from the geometry.
QgsCurve *	toCurveType () const override
	Returns the geometry converted to the more generic curve type.
void	transform (const QgsCoordinateTransform &ct, Qgis::TransformDirection d=Qgis::TransformDirection::Forward, bool transformZ=false) override
	Transforms the geometry using a coordinate transform.
void	transform (const QTransform &t, double zTranslate=0.0, double zScale=1.0, double mTranslate=0.0, double mScale=1.0) override
	Transforms the x and y components of the geometry using a QTransform object t.
bool	transform (QgsAbstractGeometryTransformer transformer, QgsFeedback feedback=nullptr) override
	Transforms the vertices from the geometry in place, using the specified geometry transformer object.
double	vertexAngle (QgsVertexId vertex) const override
	Returns approximate angle at a vertex.
QgsPoint	vertexAt (QgsVertexId id) const override
	Returns the point corresponding to a specified vertex id.
int	vertexCount (int part=0, int ring=0) const override
	Returns the number of vertices of which this geometry is built.
int	vertexNumberFromVertexId (QgsVertexId id) const override
	Returns the vertex number corresponding to a vertex id.
double	weight (int index) const
	Returns the weight at the specified control point index.
QVector< double >	weights () const
	Returns the weight vector of the NURBS curve.
int	wkbSize (QgsAbstractGeometry::WkbFlags flags=QgsAbstractGeometry::WkbFlags()) const override
	Returns the length of the QByteArray returned by asWkb().
double	xAt (int index) const override
	Returns the x-coordinate of the specified node in the line string.
double	yAt (int index) const override
	Returns the y-coordinate of the specified node in the line string.
double	zAt (int index) const override
	Returns the z-coordinate of the specified node in the line string.
Public Member Functions inherited from QgsCurve
	QgsCurve ()=default
void	adjacentVertices (QgsVertexId vertex, QgsVertexId &previousVertex, QgsVertexId &nextVertex) const override
	Returns the vertices adjacent to a specified vertex within a geometry.
QPainterPath	asQPainterPath () const override
	Returns the geometry represented as a QPainterPath.
QgsAbstractGeometry *	boundary () const override
	Returns the closure of the combinatorial boundary of the geometry (ie the topological boundary of the geometry).
QgsCoordinateSequence	coordinateSequence () const override
	Retrieves the sequence of geometries, rings and nodes.
virtual bool	isRing () const
	Returns `true` if the curve is a ring.
bool	nextVertex (QgsVertexId &id, QgsPoint &vertex) const override
	Returns next vertex id and coordinates.
void	normalize () final
	Reorganizes the geometry into a normalized form (or "canonical" form).
bool	operator!= (const QgsAbstractGeometry &other) const override
bool	operator== (const QgsAbstractGeometry &other) const override
Qgis::AngularDirection	orientation () const
	Returns the curve's orientation, e.g.
int	ringCount (int part=0) const override
	Returns the number of rings of which this geometry is built.
QgsCurve *	segmentize (double tolerance=M_PI_2/90, SegmentationToleranceType toleranceType=MaximumAngle) const override
	Returns a geometry without curves.
double	sinuosity () const
	Returns the curve sinuosity, which is the ratio of the curve length() to curve straightDistance2d().
double	straightDistance2d () const
	Returns the straight distance of the curve, i.e.
Public Member Functions inherited from QgsAbstractGeometry
	QgsAbstractGeometry ()=default
	QgsAbstractGeometry (const QgsAbstractGeometry &geom)
virtual	~QgsAbstractGeometry ()=default
virtual double	area () const
	Returns the planar, 2-dimensional area of the geometry.
virtual double	area3D () const
	Returns the 3-dimensional surface area of the geometry.
QString	asJson (int precision=17)
	Returns a GeoJSON representation of the geometry as a QString.
virtual int	compareTo (const QgsAbstractGeometry *other) const
	Comparator for sorting of geometry.
const_part_iterator	const_parts_begin () const
	Returns STL-style iterator pointing to the const first part of the geometry.
const_part_iterator	const_parts_end () const
	Returns STL-style iterator pointing to the imaginary const part after the last part of the geometry.
virtual bool	convertTo (Qgis::WkbType type)
	Converts the geometry to a specified type.
virtual void	filterVertices (const std::function< bool(const QgsPoint &) > &filter)
	Filters the vertices from the geometry in place, removing any which do not return `true` for the filter function check.
bool	is3D () const
	Returns `true` if the geometry is 3D and contains a z-value.
bool	isMeasure () const
	Returns `true` if the geometry contains m values.
virtual int	nCoordinates () const
	Returns the number of nodes contained in the geometry.
QgsAbstractGeometry &	operator= (const QgsAbstractGeometry &geom)
QgsGeometryPartIterator	parts ()
	Returns Java-style iterator for traversal of parts of the geometry.
QgsGeometryConstPartIterator	parts () const
	Returns Java-style iterator for traversal of parts of the geometry.
part_iterator	parts_begin ()
	Returns STL-style iterator pointing to the first part of the geometry.
part_iterator	parts_end ()
	Returns STL-style iterator pointing to the imaginary part after the last part of the geometry.
virtual double	perimeter () const
	Returns the planar, 2-dimensional perimeter of the geometry.
virtual const QgsAbstractGeometry *	simplifiedTypeRef () const
	Returns a reference to the simplest lossless representation of this geometry, e.g.
virtual void	transformVertices (const std::function< QgsPoint(const QgsPoint &) > &transform)
	Transforms the vertices from the geometry in place, applying the transform function to every vertex.
QgsVertexIterator	vertices () const
	Returns a read-only, Java-style iterator for traversal of vertices of all the geometry, including all geometry parts and rings.
vertex_iterator	vertices_begin () const
	Returns STL-style iterator pointing to the first vertex of the geometry.
vertex_iterator	vertices_end () const
	Returns STL-style iterator pointing to the imaginary vertex after the last vertex of the geometry.
Qgis::WkbType	wkbType () const
	Returns the WKB type of the geometry.
QString	wktTypeStr () const
	Returns the WKT type string of the geometry.

Static Public Member Functions
static const QgsNurbsCurve *	cast (const QgsAbstractGeometry *geom)
	Cast the geom to a QgsNurbsCurve.
static QgsNurbsCurve *	cast (QgsAbstractGeometry *geom)
	Cast the geom to a QgsNurbsCurve.
Static Public Member Functions inherited from QgsCurve
static const QgsCurve *	cast (const QgsAbstractGeometry *geom)
	Cast the geom to a QgsCurve.
static QgsCurve *	cast (QgsAbstractGeometry *geom)
	Cast the geom to a QgsCurve.

Protected Member Functions
QgsBox3D	calculateBoundingBox3D () const override
	Calculates the minimal 3D bounding box for the geometry.
void	clearCache () const override
	Clears any cached parameters associated with the geometry, e.g., bounding boxes.
int	compareToSameClass (const QgsAbstractGeometry *other) const final
	Compares to an other geometry of the same class, and returns a integer for sorting of the two geometries.
Protected Member Functions inherited from QgsCurve
int	childCount () const override
	Returns number of child geometries (for geometries with child geometries) or child points (for geometries without child geometries - i.e.
QgsPoint	childPoint (int index) const override
	Returns point at index (for geometries without child geometries - i.e.
bool	snapToGridPrivate (double hSpacing, double vSpacing, double dSpacing, double mSpacing, const QVector< double > &srcX, const QVector< double > &srcY, const QVector< double > &srcZ, const QVector< double > &srcM, QVector< double > &outX, QVector< double > &outY, QVector< double > &outZ, QVector< double > &outM, bool removeRedundantPoints) const
	Helper function for QgsCurve subclasses to snap to grids.
Protected Member Functions inherited from QgsAbstractGeometry
virtual QgsRectangle	calculateBoundingBox () const
	Default calculator for the minimal bounding box for the geometry.
virtual QgsAbstractGeometry *	childGeometry (int index) const
	Returns pointer to child geometry (for geometries with child geometries - i.e.
virtual bool	hasChildGeometries () const
	Returns whether the geometry has any child geometries (`false` for point / curve, `true` otherwise).
void	setZMTypeFromSubGeometry (const QgsAbstractGeometry *subggeom, Qgis::WkbType baseGeomType)
	Updates the geometry type based on whether sub geometries contain z or m values.
int	sortIndex () const
	Returns the sort index for the geometry, used in the compareTo() method to compare geometries of different types.

Additional Inherited Members
Public Types inherited from QgsAbstractGeometry
enum	AxisOrder { XY = 0 , YX }
	Axis order for GML generation. More...
enum	SegmentationToleranceType { MaximumAngle = 0 , MaximumDifference }
	Segmentation tolerance as maximum angle or maximum difference between approximation and circle. More...
enum	WkbFlag { FlagExportTrianglesAsPolygons = 1 << 0 , FlagExportNanAsDoubleMin = 1 << 1 }
	WKB export flags. More...
typedef QFlags< WkbFlag >	WkbFlags
Protected Attributes inherited from QgsCurve
QgsBox3D	mBoundingBox
	Cached bounding box.
bool	mHasCachedSummedUpArea = false
bool	mHasCachedSummedUpArea3D = false
double	mSummedUpArea = 0
double	mSummedUpArea3D = 0
Protected Attributes inherited from QgsAbstractGeometry
Qgis::WkbType	mWkbType = Qgis::WkbType::Unknown

Detailed Description

Represents a NURBS (Non-Uniform Rational B-Spline) curve geometry in 2D/3D.

NURBS curves are a mathematical model commonly used in computer graphics for representing curves. They are parametric curves defined by control points, weights, knot vectors, and a degree.

Since: QGIS 4.0

Definition at line 41 of file qgsnurbscurve.h.

Constructor & Destructor Documentation

◆ QgsNurbsCurve() [1/2]

QgsNurbsCurve::QgsNurbsCurve ( )

Constructor for an empty NURBS curve geometry.

Definition at line 44 of file qgsnurbscurve.cpp.

◆ QgsNurbsCurve() [2/2]

QgsNurbsCurve::QgsNurbsCurve	(	const QVector< QgsPoint > &	controlPoints,
		int	degree,
		const QVector< double > &	knots,
		const QVector< double > &	weights )

Constructs a NURBS curve from control points, degree, knot vector and weights.

Parameters

controlPoints	control points defining the curve. The number of control points must be strictly greater than degree
degree	degree of the NURBS curve (must be >= 1, typically 1-3)
knots	knot vector (must have size = control points count + degree + 1, values must be non-decreasing)
weights	weight vector for rational curves (same size as control points)

Definition at line 49 of file qgsnurbscurve.cpp.

Member Function Documentation

◆ addMValue()

bool QgsNurbsCurve::addMValue ( double mValue = 0 )

overridevirtual

Adds a measure to the geometry, initialized to a preset value.

Parameters

mValue initial m-value for all nodes

Returns: true on success

See also: dropMValue(); addZValue()

Implements QgsAbstractGeometry.

Definition at line 545 of file qgsnurbscurve.cpp.

◆ addToPainterPath()

void QgsNurbsCurve::addToPainterPath ( QPainterPath & path ) const

overridevirtual

Adds a curve to a painter path.

Implements QgsCurve.

Definition at line 1156 of file qgsnurbscurve.cpp.

◆ addZValue()

bool QgsNurbsCurve::addZValue ( double zValue = 0 )

overridevirtual

Adds a z-dimension to the geometry, initialized to a preset value.

Parameters

zValue initial z-value for all nodes

Returns: true on success

See also: dropZValue(); addMValue()

Implements QgsAbstractGeometry.

Definition at line 529 of file qgsnurbscurve.cpp.

◆ asGml2()

QDomElement QgsNurbsCurve::asGml2	(	QDomDocument &	doc,
		int	precision = 17,
		const QString &	ns = "gml",
		QgsAbstractGeometry::AxisOrder	axisOrder = QgsAbstractGeometry::AxisOrder::XY ) const

overridevirtual

Returns a GML2 representation of the geometry.

Parameters

doc	DOM document
precision	number of decimal places for coordinates
ns	XML namespace
axisOrder	Axis order for generated GML

See also: asWkb(); asWkt(); asGml3(); asJson()

Implements QgsAbstractGeometry.

Definition at line 1602 of file qgsnurbscurve.cpp.

◆ asGml3()

QDomElement QgsNurbsCurve::asGml3	(	QDomDocument &	doc,
		int	precision = 17,
		const QString &	ns = "gml",
		QgsAbstractGeometry::AxisOrder	axisOrder = QgsAbstractGeometry::AxisOrder::XY ) const

overridevirtual

Returns a GML3 representation of the geometry.

Parameters

doc	DOM document
precision	number of decimal places for coordinates
ns	XML namespace
axisOrder	Axis order for generated GML

See also: asWkb(); asWkt(); asGml2(); asJson()

Implements QgsAbstractGeometry.

Definition at line 1612 of file qgsnurbscurve.cpp.

◆ asJsonObject()

json QgsNurbsCurve::asJsonObject ( int precision = 17 ) const

overridevirtual

Returns a json object representation of the geometry.

See also: asWkb(); asWkt(); asGml2(); asGml3(); asJson()

Note: not available in Python bindings

Since: QGIS 3.10

Reimplemented from QgsAbstractGeometry.

Definition at line 1622 of file qgsnurbscurve.cpp.

◆ asKml()

QString QgsNurbsCurve::asKml ( int precision = 17 ) const

overridevirtual

Returns a KML representation of the geometry.

Since: QGIS 3.12

Reimplemented from QgsCurve.

Definition at line 1630 of file qgsnurbscurve.cpp.

◆ asQPolygonF()

QPolygonF QgsNurbsCurve::asQPolygonF ( ) const

overridevirtual

Returns a QPolygonF representing the points.

Reimplemented from QgsCurve.

Definition at line 336 of file qgsnurbscurve.cpp.

◆ asWkb()

QByteArray QgsNurbsCurve::asWkb ( QgsAbstractGeometry::WkbFlags flags = QgsAbstractGeometry::WkbFlags() ) const

overridevirtual

Returns a WKB representation of the geometry.

The optional flags argument specifies flags controlling WKB export behavior (since QGIS 3.14).

See also: asWkt; asGml2; asGml3; asJson()

Implements QgsAbstractGeometry.

Definition at line 1478 of file qgsnurbscurve.cpp.

◆ asWkt()

QString QgsNurbsCurve::asWkt ( int precision = 17 ) const

overridevirtual

Returns a WKT representation of the geometry.

Parameters

precision number of decimal places for coordinates

See also: asWkb(); asGml2(); asGml3(); asJson()

Implements QgsAbstractGeometry.

Definition at line 1537 of file qgsnurbscurve.cpp.

◆ boundingBox()

QgsRectangle QgsNurbsCurve::boundingBox ( ) const

overridevirtual

Returns the minimal bounding box for the geometry.

Reimplemented from QgsAbstractGeometry.

Definition at line 1356 of file qgsnurbscurve.cpp.

◆ boundingBox3D()

QgsBox3D QgsNurbsCurve::boundingBox3D ( ) const

overridevirtual

Returns the 3D bounding box for the geometry.

Since: QGIS 3.34

Reimplemented from QgsCurve.

Definition at line 1361 of file qgsnurbscurve.cpp.

◆ boundingBoxIntersects() [1/2]

bool QgsNurbsCurve::boundingBoxIntersects ( const QgsBox3D & box3d ) const

overridevirtual

Returns true if the bounding box of this geometry intersects with a box3d.

Since this test only considers the bounding box of the geometry, is is very fast to calculate and handles invalid geometries.

Since: QGIS 3.34

Reimplemented from QgsAbstractGeometry.

Definition at line 1663 of file qgsnurbscurve.cpp.

◆ boundingBoxIntersects() [2/2]

bool QgsNurbsCurve::boundingBoxIntersects ( const QgsRectangle & rectangle ) const

overridevirtual

Returns true if the bounding box of this geometry intersects with a rectangle.

Since this test only considers the bounding box of the geometry, is is very fast to calculate and handles invalid geometries.

Since: QGIS 3.20

Reimplemented from QgsAbstractGeometry.

Definition at line 1658 of file qgsnurbscurve.cpp.

◆ calculateBoundingBox3D()

QgsBox3D QgsNurbsCurve::calculateBoundingBox3D ( ) const

overrideprotectedvirtual

Calculates the minimal 3D bounding box for the geometry.

See also: calculateBoundingBox()

Since: QGIS 3.34

Reimplemented from QgsAbstractGeometry.

Definition at line 1370 of file qgsnurbscurve.cpp.

◆ cast() [1/2]

const QgsNurbsCurve * QgsNurbsCurve::cast ( const QgsAbstractGeometry * geom )

inlinestatic

Cast the geom to a QgsNurbsCurve.

Should be used by qgsgeometry_cast<QgsNurbsCurve *>( geometry ).

Note: Not available in Python.

Definition at line 328 of file qgsnurbscurve.h.

◆ cast() [2/2]

QgsNurbsCurve * QgsNurbsCurve::cast ( QgsAbstractGeometry * geom )

inlinestatic

Cast the geom to a QgsNurbsCurve.

Should be used by qgsgeometry_cast<QgsNurbsCurve *>( geometry ).

Note: Not available in Python.

Definition at line 340 of file qgsnurbscurve.h.

◆ centroid()

QgsPoint QgsNurbsCurve::centroid ( ) const

overridevirtual

Returns the centroid of the geometry.

Reimplemented from QgsAbstractGeometry.

Definition at line 1668 of file qgsnurbscurve.cpp.

◆ clear()

void QgsNurbsCurve::clear ( )

overridevirtual

Clears the geometry, ie reset it to a null geometry.

Implements QgsAbstractGeometry.

Definition at line 1649 of file qgsnurbscurve.cpp.

◆ clearCache()

void QgsNurbsCurve::clearCache ( ) const

overrideprotectedvirtual

Clears any cached parameters associated with the geometry, e.g., bounding boxes.

Reimplemented from QgsCurve.

Definition at line 1393 of file qgsnurbscurve.cpp.

◆ clone()

QgsNurbsCurve * QgsNurbsCurve::clone ( ) const

overridevirtual

Clones the geometry by performing a deep copy.

Implements QgsCurve.

Definition at line 68 of file qgsnurbscurve.cpp.

◆ closestSegment()

double QgsNurbsCurve::closestSegment	(	const QgsPoint &	pt,
		QgsPoint &	segmentPt,
		QgsVertexId &	vertexAfter,
		int *	leftOf = nullptr,
		double	epsilon = 4 *std::numeric_limits< double >::epsilon() ) const

overridevirtual

Searches for the closest segment of the geometry to a given point.

Parameters

pt	specifies the point to find closest segment to
segmentPt	storage for the closest point within the geometry
vertexAfter	storage for the ID of the vertex at the end of the closest segment
leftOf	indicates whether the point lies on the left side of the geometry (-1 if point is to the left of the geometry, +1 if the point is to the right of the geometry, or 0 for cases where left/right could not be determined, e.g. point exactly on a line) `false` if point is to right of segment)
epsilon	epsilon for segment snapping

Returns: squared distance to closest segment or negative value on error

Implements QgsAbstractGeometry.

Definition at line 1310 of file qgsnurbscurve.cpp.

◆ compareToSameClass()

int QgsNurbsCurve::compareToSameClass ( const QgsAbstractGeometry * other ) const

finalprotectedvirtual

Compares to an other geometry of the same class, and returns a integer for sorting of the two geometries.

Note: The actual logic for the sorting is an internal detail only and is subject to change between QGIS versions. The result should only be used for direct comparison of geometries and not stored for later use.

Since: QGIS 3.20

Implements QgsAbstractGeometry.

Definition at line 1674 of file qgsnurbscurve.cpp.

◆ controlPoints()

QVector< QgsPoint > QgsNurbsCurve::controlPoints ( ) const

inline

Returns the control points of the NURBS curve.

Definition at line 215 of file qgsnurbscurve.h.

◆ createEmptyWithSameType()

QgsAbstractGeometry * QgsNurbsCurve::createEmptyWithSameType ( ) const

overridevirtual

Creates a new geometry with the same class and same WKB type as the original and transfers ownership.

To create it, the geometry is default constructed and then the WKB is changed.

See also: clone()

Implements QgsAbstractGeometry.

Definition at line 1305 of file qgsnurbscurve.cpp.

◆ curveSubstring()

QgsCurve * QgsNurbsCurve::curveSubstring	(	double	startDistance,
		double	endDistance ) const

overridevirtual

Returns a new curve representing a substring of this curve.

The startDistance and endDistance arguments specify the length along the curve which the substring should start and end at. If the endDistance is greater than the total length of the curve then any "extra" length will be ignored.

If z or m values are present, the output z and m will be interpolated using the existing vertices' z or m values.

Since: QGIS 3.4

Implements QgsCurve.

Definition at line 1163 of file qgsnurbscurve.cpp.

◆ curveToLine()

QgsLineString * QgsNurbsCurve::curveToLine	(	double	tolerance = M_PI_2/90,
		SegmentationToleranceType	toleranceType = MaximumAngle ) const

overridevirtual

Returns a new line string geometry corresponding to a segmentized approximation of the curve.

Parameters

tolerance	segmentation tolerance
toleranceType	maximum segmentation angle or maximum difference between approximation and curve

Uses a MaximumAngle tolerance of 1 degrees by default (360 segments in a full circle)

Implements QgsCurve.

Definition at line 303 of file qgsnurbscurve.cpp.

◆ degree()

int QgsNurbsCurve::degree ( ) const

inline

Returns the degree of the NURBS curve.

Definition at line 200 of file qgsnurbscurve.h.

◆ deleteVertex()

bool QgsNurbsCurve::deleteVertex ( QgsVertexId position )

overridevirtual

Deletes a vertex within the geometry.

Parameters

position vertex id for vertex to delete

Returns: true if delete was successful

See also: insertVertex; moveVertex

Implements QgsAbstractGeometry.

Definition at line 591 of file qgsnurbscurve.cpp.

◆ dimension()

int QgsNurbsCurve::dimension ( ) const

overridevirtual

Returns the inherent dimension of the geometry.

For example, this is 0 for a point geometry, 1 for a linestring and 2 for a polygon.

Implements QgsAbstractGeometry.

Definition at line 1639 of file qgsnurbscurve.cpp.

◆ distanceBetweenVertices()

double QgsNurbsCurve::distanceBetweenVertices	(	QgsVertexId	fromVertex,
		QgsVertexId	toVertex ) const

overridevirtual

Returns the distance along the curve between two vertices.

This method calculates the accumulated distance along the curve from one vertex to another. For circular strings, this includes following the arc path precisely.

Note: For 3D geometries, the distance calculation includes the Z coordinate component.

Parameters

fromVertex	the starting vertex ID
toVertex	the ending vertex ID

Returns: distance along the curve between the vertices, or -1 if either vertex is invalid

Since: QGIS 4.00

Implements QgsCurve.

Definition at line 1185 of file qgsnurbscurve.cpp.

◆ draw()

void QgsNurbsCurve::draw ( QPainter & p ) const

overridevirtual

Draws the geometry using the specified QPainter.

Parameters

p	destination QPainter

Implements QgsAbstractGeometry.

Definition at line 322 of file qgsnurbscurve.cpp.

◆ drawAsPolygon()

void QgsNurbsCurve::drawAsPolygon ( QPainter & p ) const

overridevirtual

Draws the curve as a polygon on the specified QPainter.

Parameters

p	destination QPainter

Implements QgsCurve.

Definition at line 329 of file qgsnurbscurve.cpp.

◆ dropMValue()

bool QgsNurbsCurve::dropMValue ( )

overridevirtual

Drops any measure values which exist in the geometry.

Returns: true if m-values were present and have been removed

See also: addMValue(); dropZValue()

Implements QgsAbstractGeometry.

Definition at line 576 of file qgsnurbscurve.cpp.

◆ dropZValue()

bool QgsNurbsCurve::dropZValue ( )

overridevirtual

Drops any z-dimensions which exist in the geometry.

Returns: true if Z values were present and have been removed

See also: addZValue(); dropMValue()

Implements QgsAbstractGeometry.

Definition at line 561 of file qgsnurbscurve.cpp.

◆ endPoint()

QgsPoint QgsNurbsCurve::endPoint ( ) const

overridevirtual

Returns the end point of the curve.

See also: startPoint

Implements QgsCurve.

Definition at line 342 of file qgsnurbscurve.cpp.

◆ equals()

bool QgsNurbsCurve::equals ( const QgsCurve & other ) const

overridevirtual

Checks whether this curve exactly equals another curve.

Implements QgsCurve.

Definition at line 347 of file qgsnurbscurve.cpp.

◆ evaluate()

QgsPoint QgsNurbsCurve::evaluate ( double t ) const

nodiscard

Evaluates the NURBS curve at parameter t ∈ [0,1].

Uses the Cox-de Boor algorithm for B-spline basis function evaluation.

Parameters

t	parameter value between 0 and 1

Returns: point on the curve at parameter t

Definition at line 166 of file qgsnurbscurve.cpp.

◆ filterVertices()

void QgsNurbsCurve::filterVertices ( const std::function< bool(const QgsPoint &)> & filter )

override

Definition at line 614 of file qgsnurbscurve.cpp.

◆ fromWkb()

bool QgsNurbsCurve::fromWkb ( QgsConstWkbPtr & wkb )

overridevirtual

Sets the geometry from a WKB string.

After successful read the wkb argument will be at the position where the reading has stopped.

See also: fromWkt

Implements QgsAbstractGeometry.

Definition at line 652 of file qgsnurbscurve.cpp.

◆ fromWkt()

bool QgsNurbsCurve::fromWkt ( const QString & wkt )

overridevirtual

Sets the geometry from a WKT string.

See also: fromWkb

Implements QgsAbstractGeometry.

Definition at line 775 of file qgsnurbscurve.cpp.

◆ fuzzyDistanceEqual()

bool QgsNurbsCurve::fuzzyDistanceEqual	(	const QgsAbstractGeometry &	other,
		double	epsilon = 1e-8 ) const

overridevirtual

Performs fuzzy distance comparison between this geometry and other using an epsilon.

Traditionally, the comparison is done by examining the specific values (such as x and y) that define the location of vertices in the geometry. It focuses on the numerical differences or relationships between these values. On the other hand, comparing distances between points considers the actual spatial separation or length between the points, regardless of their coordinate values. This comparison involves measuring the distance between two points using formulas like the distance formula. Here, it's the "distance comparison" (fuzzyDistanceEqual).

See also: fuzzyEqual; QgsGeometryUtilsBase::fuzzyEqual

Since: QGIS 3.36

Implements QgsAbstractGeometry.

Definition at line 1049 of file qgsnurbscurve.cpp.

◆ fuzzyEqual()

bool QgsNurbsCurve::fuzzyEqual	(	const QgsAbstractGeometry &	other,
		double	epsilon = 1e-8 ) const

overridevirtual

Performs fuzzy comparison between this geometry and other using an epsilon.

The comparison is done by examining the specific values (such as x and y) that define the location of vertices in the geometry.

See also: fuzzyDistanceEqual; QgsGeometryUtilsBase::fuzzyDistanceEqual

Since: QGIS 3.36

Implements QgsAbstractGeometry.

Definition at line 1017 of file qgsnurbscurve.cpp.

◆ geometryType()

QString QgsNurbsCurve::geometryType ( ) const

overridevirtual

Returns a unique string representing the geometry type.

See also: wkbType; wktTypeStr

Implements QgsAbstractGeometry.

Definition at line 1054 of file qgsnurbscurve.cpp.

◆ hasCurvedSegments()

bool QgsNurbsCurve::hasCurvedSegments ( ) const

overridevirtual

Returns true if the geometry contains curved segments.

Reimplemented from QgsAbstractGeometry.

Definition at line 1059 of file qgsnurbscurve.cpp.

◆ indexOf()

int QgsNurbsCurve::indexOf ( const QgsPoint & point ) const

overridevirtual

Returns the index of the first vertex matching the given point, or -1 if a matching vertex is not found.

Note: If the curve has m or z values then the search point must have exactly matching m and z values in order to be matched against the curve's vertices.; This method only matches against segment vertices, not curve vertices.

Since: QGIS 3.20

Implements QgsCurve.

Definition at line 375 of file qgsnurbscurve.cpp.

◆ insertVertex()

bool QgsNurbsCurve::insertVertex	(	QgsVertexId	position,
		const QgsPoint &	vertex )

overridevirtual

Inserts a vertex into the geometry.

Parameters

position	vertex id for position of inserted vertex
vertex	vertex to insert

Returns: true if insert was successful

See also: moveVertex; deleteVertex

Implements QgsAbstractGeometry.

Definition at line 1414 of file qgsnurbscurve.cpp.

◆ interpolatePoint()

QgsPoint * QgsNurbsCurve::interpolatePoint ( double distance ) const

overridevirtual

Returns an interpolated point on the curve at the specified distance.

If z or m values are present, the output z and m will be interpolated using the existing vertices' z or m values.

If distance is negative, or is greater than the length of the curve, nullptr will be returned.

Since: QGIS 3.4

Implements QgsCurve.

Definition at line 387 of file qgsnurbscurve.cpp.

◆ isBezier()

bool QgsNurbsCurve::isBezier ( ) const

Returns true if this curve represents a Bézier curve.

A Bézier curve is a special case of NURBS with uniform weights and specific knot vector.

Definition at line 73 of file qgsnurbscurve.cpp.

◆ isBSpline()

bool QgsNurbsCurve::isBSpline ( ) const

Returns true if this curve represents a B-spline (non-rational NURBS).

Definition at line 102 of file qgsnurbscurve.cpp.

◆ isClosed()

bool QgsNurbsCurve::isClosed ( ) const

overridevirtual

Returns true if the curve is closed.

See also: isClosed2D()

Reimplemented from QgsCurve.

Definition at line 274 of file qgsnurbscurve.cpp.

◆ isClosed2D()

bool QgsNurbsCurve::isClosed2D ( ) const

overridevirtual

Returns true if the curve is closed.

Unlike isClosed. It looks only for XY coordinates.

See also: isClosed()

Since: QGIS 3.20

Reimplemented from QgsCurve.

Definition at line 291 of file qgsnurbscurve.cpp.

◆ isEmpty()

bool QgsNurbsCurve::isEmpty ( ) const

overridevirtual

Returns true if the geometry is empty.

Reimplemented from QgsAbstractGeometry.

Definition at line 1644 of file qgsnurbscurve.cpp.

◆ isPolyBezier()

bool QgsNurbsCurve::isPolyBezier ( ) const

Returns true if this curve represents a poly-Bézier curve.

A poly-Bézier is a degree 3 NURBS with (n-1) divisible by 3, where n is the number of control points.

Definition at line 117 of file qgsnurbscurve.cpp.

◆ isRational()

bool QgsNurbsCurve::isRational ( ) const

Returns true if this curve is rational (has non-uniform weights).

Definition at line 112 of file qgsnurbscurve.cpp.

◆ isValid()

bool QgsNurbsCurve::isValid	(	QString &	error,
		Qgis::GeometryValidityFlags	flags = Qgis::GeometryValidityFlags() ) const

overridevirtual

Checks validity of the geometry, and returns true if the geometry is valid.

Parameters

error	will be set to the validity error message
flags	indicates optional flags which control the type of validity checking performed (corresponding to Qgis::GeometryValidityFlags).

Returns: true if geometry is valid

Since: QGIS 3.8

Reimplemented from QgsCurve.

Definition at line 1102 of file qgsnurbscurve.cpp.

◆ knots()

QVector< double > QgsNurbsCurve::knots ( ) const

inline

Returns the knot vector of the NURBS curve.

Definition at line 230 of file qgsnurbscurve.h.

◆ length()

double QgsNurbsCurve::length ( ) const

overridevirtual

Returns the planar, 2-dimensional length of the geometry.

Warning: QgsAbstractGeometry objects are inherently Cartesian/planar geometries, and the length returned by this method is calculated using strictly Cartesian mathematics. In contrast, the QgsDistanceArea class exposes methods for calculating the lengths of geometries using geodesic calculations which account for the curvature of the Earth (or any other celestial body).

See also: area(); perimeter()

Reimplemented from QgsAbstractGeometry.

Definition at line 1171 of file qgsnurbscurve.cpp.

◆ mAt()

double QgsNurbsCurve::mAt ( int index ) const

overridevirtual

Returns the m-coordinate of the specified node in the line string.

Parameters

index index of node, where the first node in the line is 0

Returns: m-coordinate of node, or 0.0 if index is out of bounds

Since: QGIS 3.28

Implements QgsCurve.

Definition at line 522 of file qgsnurbscurve.cpp.

◆ moveVertex()

bool QgsNurbsCurve::moveVertex	(	QgsVertexId	position,
		const QgsPoint &	newPos )

overridevirtual

Moves a vertex within the geometry.

Parameters

position	vertex id for vertex to move
newPos	new position of vertex

Returns: true if move was successful

See also: insertVertex; deleteVertex

Implements QgsAbstractGeometry.

Definition at line 1400 of file qgsnurbscurve.cpp.

◆ numPoints()

int QgsNurbsCurve::numPoints ( ) const

overridevirtual

Returns the number of points in the curve.

Implements QgsCurve.

Definition at line 397 of file qgsnurbscurve.cpp.

◆ partCount()

int QgsNurbsCurve::partCount ( ) const

overridevirtual

Returns count of parts contained in the geometry.

See also: vertexCount; ringCount

Reimplemented from QgsCurve.

Definition at line 1064 of file qgsnurbscurve.cpp.

◆ pointAt()

bool QgsNurbsCurve::pointAt	(	int	node,
		QgsPoint &	point,
		Qgis::VertexType &	type ) const

overridevirtual

Returns the point and vertex id of a point within the curve.

Parameters

node	node number, where the first node is 0
point	will be set to point at corresponding node in the curve
type	will be set to the vertex type of the node

Returns: true if node exists within the curve

Implements QgsCurve.

Definition at line 402 of file qgsnurbscurve.cpp.

◆ points()

void QgsNurbsCurve::points ( QgsPointSequence & pt ) const

overridevirtual

Returns a list of points within the curve.

Implements QgsCurve.

Definition at line 413 of file qgsnurbscurve.cpp.

◆ removeDuplicateNodes()

bool QgsNurbsCurve::removeDuplicateNodes	(	double	epsilon = 4 *std::numeric_limits< double >::epsilon(),
		bool	useZValues = false )

overridevirtual

Removes duplicate nodes from the geometry, wherever removing the nodes does not result in a degenerate geometry.

The epsilon parameter specifies the tolerance for coordinates when determining that vertices are identical.

By default, z values are not considered when detecting duplicate nodes. E.g. two nodes with the same x and y coordinate but different z values will still be considered duplicate and one will be removed. If useZValues is true, then the z values are also tested and nodes with the same x and y but different z will be maintained.

Note that duplicate nodes are not tested between different parts of a multipart geometry. E.g. a multipoint geometry with overlapping points will not be changed by this method.

The function will return true if nodes were removed, or false if no duplicate nodes were found.

Implements QgsAbstractGeometry.

Definition at line 1222 of file qgsnurbscurve.cpp.

◆ reversed()

QgsCurve * QgsNurbsCurve::reversed ( ) const

overridevirtual

Returns a reversed copy of the curve, where the direction of the curve has been flipped.

Implements QgsCurve.

Definition at line 422 of file qgsnurbscurve.cpp.

◆ scroll()

void QgsNurbsCurve::scroll ( int firstVertexIndex )

overridevirtual

Scrolls the curve vertices so that they start with the vertex at the given index.

Warning: This should only be called on closed curves, or the shape of the curve will be altered and the result is undefined.; The firstVertexIndex must correspond to a segment vertex and not a curve point or the result is undefined.

Since: QGIS 3.20

Implements QgsCurve.

Definition at line 443 of file qgsnurbscurve.cpp.

◆ segmentLength()

double QgsNurbsCurve::segmentLength ( QgsVertexId startVertex ) const

overridevirtual

Returns the length of the segment of the geometry which begins at startVertex.

Warning: QgsAbstractGeometry objects are inherently Cartesian/planar geometries, and the lengths returned by this method are calculated using strictly Cartesian mathematics.

Implements QgsAbstractGeometry.

Definition at line 1177 of file qgsnurbscurve.cpp.

◆ setControlPoints()

void QgsNurbsCurve::setControlPoints ( const QVector< QgsPoint > & points )

inline

Sets the control points of the NURBS curve.

Parameters

points control points

Definition at line 221 of file qgsnurbscurve.h.

◆ setDegree()

void QgsNurbsCurve::setDegree ( int degree )

inline

Sets the degree of the NURBS curve.

Parameters

degree curve degree (typically 1-3)

Definition at line 206 of file qgsnurbscurve.h.

◆ setKnots()

void QgsNurbsCurve::setKnots ( const QVector< double > & knots )

inline

Sets the knot vector of the NURBS curve.

Parameters

knots knot vector (must have size = control points count + degree + 1, values must be non-decreasing)

Definition at line 236 of file qgsnurbscurve.h.

◆ setWeight()

bool QgsNurbsCurve::setWeight	(	int	index,
		double	weight )

Sets the weight at the specified control point index.

Weight must be positive (> 0).

Returns: true if successful, false if index is out of range or weight is invalid.

Since: QGIS 4.0

Definition at line 1741 of file qgsnurbscurve.cpp.

◆ setWeights()

void QgsNurbsCurve::setWeights ( const QVector< double > & weights )

inline

Sets the weight vector of the NURBS curve.

Parameters

weights weight vector (same size as control points)

Definition at line 251 of file qgsnurbscurve.h.

◆ simplifyByDistance()

QgsAbstractGeometry * QgsNurbsCurve::simplifyByDistance ( double tolerance ) const

overridevirtual

Simplifies the geometry by applying the Douglas Peucker simplification by distance algorithm.

The caller takes ownership of the returned geometry. Curved geometries will be segmentized prior to simplification.

If a simplified geometry cannot be calculated nullptr will be returned.

The returned geometry may be invalid and contain self-intersecting rings.

Since: QGIS 3.38

Implements QgsAbstractGeometry.

Definition at line 1214 of file qgsnurbscurve.cpp.

◆ snappedToGrid()

QgsAbstractGeometry * QgsNurbsCurve::snappedToGrid	(	double	hSpacing,
		double	vSpacing,
		double	dSpacing = 0,
		double	mSpacing = 0,
		bool	removeRedundantPoints = false ) const

overridevirtual

Makes a new geometry with all the points or vertices snapped to the closest point of the grid.

Ownership is transferred to the caller.

If the gridified geometry could not be calculated nullptr will be returned. It may generate an invalid geometry (in some corner cases). It can also be thought as rounding the edges and it may be useful for removing errors.

Example:

geometry.snappedToGrid(1, 1)

In this case we use a 2D grid of 1x1 to gridify. In this case, it can be thought like rounding the x and y of all the points/vertices to full units (remove all decimals).

Parameters

hSpacing	Horizontal spacing of the grid (x axis). 0 to disable.
vSpacing	Vertical spacing of the grid (y axis). 0 to disable.
dSpacing	Depth spacing of the grid (z axis). 0 (default) to disable.
mSpacing	Custom dimension spacing of the grid (m axis). 0 (default) to disable.
removeRedundantPoints	if `true`, then points which are redundant (e.g. they represent mid points on a straight line segment) will be skipped (since QGIS 3.38)

Implements QgsAbstractGeometry.

Definition at line 1193 of file qgsnurbscurve.cpp.

◆ splitCurveAtVertex()

std::tuple< std::unique_ptr< QgsCurve >, std::unique_ptr< QgsCurve > > QgsNurbsCurve::splitCurveAtVertex ( int index ) const

overridevirtual

Splits the curve at the specified vertex index, returning two curves which represent the portion of the curve up to an including the vertex at index, and the portion of the curve from the vertex at index (inclusive) to the end of the curve.

Note: The vertex index must correspond to a segment vertex, not a curve vertex.; Not available in Python bindings.

Since: QGIS 3.20

Implements QgsCurve.

Definition at line 471 of file qgsnurbscurve.cpp.

◆ startPoint()

QgsPoint QgsNurbsCurve::startPoint ( ) const

overridevirtual

Returns the starting point of the curve.

See also: endPoint

Implements QgsCurve.

Definition at line 481 of file qgsnurbscurve.cpp.

◆ sumUpArea()

void QgsNurbsCurve::sumUpArea ( double & sum ) const

overridevirtual

Sums up the area of the curve by iterating over the vertices (shoelace formula).

Implements QgsCurve.

Definition at line 486 of file qgsnurbscurve.cpp.

◆ sumUpArea3D()

void QgsNurbsCurve::sumUpArea3D ( double & sum ) const

overridevirtual

Sums up the 3d area of the curve by iterating over the vertices (shoelace formula).

Since: QGIS 4.0

Implements QgsCurve.

Definition at line 494 of file qgsnurbscurve.cpp.

◆ swapXy()

void QgsNurbsCurve::swapXy ( )

overridevirtual

Swaps the x and y coordinates from the geometry.

This can be used to repair geometries which have accidentally had their latitude and longitude coordinates reversed.

Since: QGIS 3.2

Implements QgsAbstractGeometry.

Definition at line 1273 of file qgsnurbscurve.cpp.

◆ toCurveType()

QgsCurve * QgsNurbsCurve::toCurveType ( ) const

overridevirtual

Returns the geometry converted to the more generic curve type.

E.g. QgsLineString -> QgsCompoundCurve, QgsPolygon -> QgsCurvePolygon, QgsMultiLineString -> QgsMultiCurve, QgsMultiPolygon -> QgsMultiSurface

Returns: the converted geometry. Caller takes ownership

Reimplemented from QgsCurve.

Definition at line 1069 of file qgsnurbscurve.cpp.

◆ transform() [1/3]

void QgsNurbsCurve::transform	(	const QgsCoordinateTransform &	ct,
		Qgis::TransformDirection	d = Qgis::TransformDirection::Forward,
		bool	transformZ = false )

overridevirtual

Transforms the geometry using a coordinate transform.

Parameters

ct	coordinate transform
d	transformation direction
transformZ	set to `true` to also transform z coordinates. This requires that the z coordinates in the geometry represent height relative to the vertical datum of the source CRS (generally ellipsoidal heights) and are expressed in its vertical units (generally meters). If `false`, then z coordinates will not be changed by the transform.

Implements QgsAbstractGeometry.

Definition at line 1324 of file qgsnurbscurve.cpp.

◆ transform() [2/3]

void QgsNurbsCurve::transform	(	const QTransform &	t,
		double	zTranslate = 0.0,
		double	zScale = 1.0,
		double	mTranslate = 0.0,
		double	mScale = 1.0 )

overridevirtual

Transforms the x and y components of the geometry using a QTransform object t.

Optionally, the geometry's z values can be scaled via zScale and translated via zTranslate. Similarly, m-values can be scaled via mScale and translated via mTranslate.

Implements QgsAbstractGeometry.

Definition at line 1340 of file qgsnurbscurve.cpp.

◆ transform() [3/3]

bool QgsNurbsCurve::transform	(	QgsAbstractGeometryTransformer *	transformer,
		QgsFeedback *	feedback = nullptr )

overridevirtual

Transforms the vertices from the geometry in place, using the specified geometry transformer object.

Depending on the transformer used, this may result in an invalid geometry.

The optional feedback argument can be used to cancel the transformation before it completes. If this is done, the geometry will be left in a semi-transformed state.

Returns: true if the geometry was successfully transformed.

Since: QGIS 3.18

Implements QgsAbstractGeometry.

Definition at line 1284 of file qgsnurbscurve.cpp.

◆ vertexAngle()

double QgsNurbsCurve::vertexAngle ( QgsVertexId vertex ) const

overridevirtual

Returns approximate angle at a vertex.

This is usually the average angle between adjacent segments, and can be pictured as the orientation of a line following the curvature of the geometry at the specified vertex.

Parameters

vertex the vertex id

Returns: rotation in radians, clockwise from north

Implements QgsAbstractGeometry.

Definition at line 1265 of file qgsnurbscurve.cpp.

◆ vertexAt()

QgsPoint QgsNurbsCurve::vertexAt ( QgsVertexId id ) const

overridevirtual

Returns the point corresponding to a specified vertex id.

Reimplemented from QgsCurve.

Definition at line 1074 of file qgsnurbscurve.cpp.

◆ vertexCount()

int QgsNurbsCurve::vertexCount	(	int	part = 0,
		int	ring = 0 ) const

overridevirtual

Returns the number of vertices of which this geometry is built.

Reimplemented from QgsCurve.

Definition at line 1088 of file qgsnurbscurve.cpp.

◆ vertexNumberFromVertexId()

int QgsNurbsCurve::vertexNumberFromVertexId ( QgsVertexId id ) const

overridevirtual

Returns the vertex number corresponding to a vertex id.

The vertex numbers start at 0, so a return value of 0 corresponds to the first vertex.

Returns -1 if a corresponding vertex could not be found.

Reimplemented from QgsCurve.

Definition at line 1093 of file qgsnurbscurve.cpp.

◆ weight()

double QgsNurbsCurve::weight ( int index ) const

Returns the weight at the specified control point index.

Returns 1.0 if index is out of range.

Since: QGIS 4.0

Definition at line 1734 of file qgsnurbscurve.cpp.

◆ weights()

QVector< double > QgsNurbsCurve::weights ( ) const

inline

Returns the weight vector of the NURBS curve.

Definition at line 245 of file qgsnurbscurve.h.

◆ wkbSize()

int QgsNurbsCurve::wkbSize ( QgsAbstractGeometry::WkbFlags flags = QgsAbstractGeometry::WkbFlags() ) const

overridevirtual

Returns the length of the QByteArray returned by asWkb().

The optional flags argument specifies flags controlling WKB export behavior

Since: QGIS 3.16

Implements QgsAbstractGeometry.

Definition at line 1433 of file qgsnurbscurve.cpp.

◆ xAt()

double QgsNurbsCurve::xAt ( int index ) const

overridevirtual

Returns the x-coordinate of the specified node in the line string.

Parameters

index index of node, where the first node in the line is 0

Returns: x-coordinate of node, or 0.0 if index is out of bounds

Implements QgsCurve.

Definition at line 501 of file qgsnurbscurve.cpp.

◆ yAt()

double QgsNurbsCurve::yAt ( int index ) const

overridevirtual

Returns the y-coordinate of the specified node in the line string.

Parameters

index index of node, where the first node in the line is 0

Returns: y-coordinate of node, or 0.0 if index is out of bounds

Implements QgsCurve.

Definition at line 508 of file qgsnurbscurve.cpp.

◆ zAt()

double QgsNurbsCurve::zAt ( int index ) const

overridevirtual

Returns the z-coordinate of the specified node in the line string.

Parameters

index index of node, where the first node in the line is 0

Returns: z-coordinate of node, or 0.0 if index is out of bounds

Since: QGIS 3.28

Implements QgsCurve.

Definition at line 515 of file qgsnurbscurve.cpp.

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

/build/qgis-3.99.0+git20260124+a8882ad4560+99sid/src/core/geometry/qgsnurbscurve.h
/build/qgis-3.99.0+git20260124+a8882ad4560+99sid/src/core/geometry/qgsnurbscurve.cpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsNurbsCurve() [1/2]

◆ QgsNurbsCurve() [2/2]

Member Function Documentation

◆ addMValue()

◆ addToPainterPath()

◆ addZValue()

◆ asGml2()

◆ asGml3()

◆ asJsonObject()

◆ asKml()

◆ asQPolygonF()

◆ asWkb()

◆ asWkt()

◆ boundingBox()

◆ boundingBox3D()

◆ boundingBoxIntersects() [1/2]

◆ boundingBoxIntersects() [2/2]

◆ calculateBoundingBox3D()

◆ cast() [1/2]

◆ cast() [2/2]

◆ centroid()

◆ clear()

◆ clearCache()

◆ clone()

◆ closestSegment()

◆ compareToSameClass()

◆ controlPoints()

◆ createEmptyWithSameType()

◆ curveSubstring()

◆ curveToLine()

◆ degree()

◆ deleteVertex()

◆ dimension()

◆ distanceBetweenVertices()

◆ draw()

◆ drawAsPolygon()

◆ dropMValue()

◆ dropZValue()

◆ endPoint()

◆ equals()

◆ evaluate()

◆ filterVertices()

◆ fromWkb()

◆ fromWkt()

◆ fuzzyDistanceEqual()

◆ fuzzyEqual()

◆ geometryType()

◆ hasCurvedSegments()

◆ indexOf()

◆ insertVertex()

◆ interpolatePoint()

◆ isBezier()

◆ isBSpline()

◆ isClosed()

◆ isClosed2D()

◆ isEmpty()

◆ isPolyBezier()

◆ isRational()

◆ isValid()

◆ knots()

◆ length()

◆ mAt()

◆ moveVertex()

◆ numPoints()

◆ partCount()

◆ pointAt()

◆ points()

◆ removeDuplicateNodes()

◆ reversed()

◆ scroll()

◆ segmentLength()

◆ setControlPoints()

◆ setDegree()

◆ setKnots()