Point geometry type, with support for z-dimension and m-values. More...

#include <qgspoint.h>

Inheritance diagram for QgsPoint:

Public Member Functions
	QgsPoint (const QgsPointXY &p)
	Construct a QgsPoint from a QgsPointXY object.

	QgsPoint (double x=std::numeric_limits< double >::quiet_NaN(), double y=std::numeric_limits< double >::quiet_NaN(), double z=std::numeric_limits< double >::quiet_NaN(), double m=std::numeric_limits< double >::quiet_NaN(), Qgis::WkbType wkbType=Qgis::WkbType::Unknown)
	Construct a point with the provided initial coordinate values.

	QgsPoint (Qgis::WkbType wkbType, double x=std::numeric_limits< double >::quiet_NaN(), double y=std::numeric_limits< double >::quiet_NaN(), double z=std::numeric_limits< double >::quiet_NaN(), double m=std::numeric_limits< double >::quiet_NaN())
	Create a new point with the given wkbtype and values.

	QgsPoint (QPointF p)
	Construct a QgsPoint from a QPointF.

bool	addMValue (double mValue=0) override
	Adds a measure to the geometry, initialized to a preset value.

bool	addZValue (double zValue=0) override
	Adds a z-dimension to the geometry, initialized to a preset value.

void	adjacentVertices (QgsVertexId vertex, QgsVertexId &previousVertex, QgsVertexId &nextVertex) const override
	Returns the vertices adjacent to a specified vertex within a geometry.

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.

QPainterPath	asQPainterPath () const override
	Returns the geometry represented as a QPainterPath.

QByteArray	asWkb (QgsAbstractGeometry::WkbFlags=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.

double	azimuth (const QgsPoint &other) const
	Calculates Cartesian azimuth between this point and other one (clockwise in degree, starting from north)

QgsAbstractGeometry *	boundary () const override
	Returns the closure of the combinatorial boundary of the geometry (ie the topological boundary of 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.

void	clear () override
	Clears the geometry, ie reset it to a null geometry.

QgsPoint *	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.

bool	convertTo (Qgis::WkbType type) override
	Converts the geometry to a specified type.

QgsCoordinateSequence	coordinateSequence () const override
	Retrieves the sequence of geometries, rings and nodes.

QgsPoint *	createEmptyWithSameType () const override
	Creates a new geometry with the same class and same WKB type as the original and transfers ownership.

bool	deleteVertex (QgsVertexId position) override
	Deletes a vertex within the geometry.

int	dimension () const override
	Returns the inherent dimension of the geometry.

double	distance (const QgsPoint &other) const
	Returns the Cartesian 2D distance between this point and another point.

double	distance (double x, double y) const
	Returns the Cartesian 2D distance between this point and a specified x, y coordinate.

double	distance3D (const QgsPoint &other) const
	Returns the Cartesian 3D distance between this point and another point.

double	distance3D (double x, double y, double z) const
	Returns the Cartesian 3D distance between this point and a specified x, y, z coordinate.

double	distanceSquared (const QgsPoint &other) const
	Returns the Cartesian 2D squared distance between this point another point.

double	distanceSquared (double x, double y) const
	Returns the Cartesian 2D squared distance between this point a specified x, y coordinate.

double	distanceSquared3D (const QgsPoint &other) const
	Returns the Cartesian 3D squared distance between this point and another point.

double	distanceSquared3D (double x, double y, double z) const
	Returns the Cartesian 3D squared distance between this point and a specified x, y, z coordinate.

void	draw (QPainter &p) const override
	Draws the geometry using 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.

void	filterVertices (const std::function< bool(const QgsPoint &) > &filter) override
	Filters the vertices from the geometry in place, removing any which do not return `true` for the filter function check.

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.

double	inclination (const QgsPoint &other) const
	Calculates Cartesian inclination between this point and other one (starting from zenith = 0 to nadir = 180.

bool	insertVertex (QgsVertexId position, const QgsPoint &vertex) override
	Inserts a vertex into the geometry.

bool	isEmpty () const override
	Returns `true` if the geometry is empty.

bool	isValid (QString &error, Qgis::GeometryValidityFlags flags=Qgis::GeometryValidityFlags()) const override
	Checks validity of the geometry, and returns `true` if the geometry is valid.

double	m () const
	Returns the point's m value.

bool	moveVertex (QgsVertexId position, const QgsPoint &newPos) override
	Moves a vertex within the geometry.

int	nCoordinates () const override
	Returns the number of nodes contained in the geometry.

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

QgsPoint	operator+ (QgsVector v) const
	Adds a vector to this point.

QgsPoint &	operator+= (QgsVector v)
	Adds a vector to this point in place.

QgsVector	operator- (const QgsPoint &p) const
	Calculates the vector obtained by subtracting a point from this point.

QgsPoint	operator- (QgsVector v) const
	Subtracts a vector from this point.

QgsPoint &	operator-= (QgsVector v)
	Subtracts a vector from this point in place.

bool	operator== (const QgsAbstractGeometry &other) const override

int	partCount () const override
	Returns count of parts contained in the geometry.

QgsPoint	project (double distance, double azimuth, double inclination=90.0) const
	Returns a new point which corresponds to this point projected by a specified distance with specified angles (azimuth and inclination), using Cartesian mathematics.

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.

int	ringCount (int=0) const override
	Returns the number of rings of which this geometry is built.

double &	rm ()
	Returns a reference to the m value of this point.

double &	rx ()
	Returns a reference to the x-coordinate of this point.

double &	ry ()
	Returns a reference to the y-coordinate of this point.

double &	rz ()
	Returns a reference to the z-coordinate of this point.

double	segmentLength (QgsVertexId startVertex) const override
	Returns the length of the segment of the geometry which begins at startVertex.

void	setM (double m)
	Sets the point's m-value.

void	setX (double x)
	Sets the point's x-coordinate.

void	setY (double y)
	Sets the point's y-coordinate.

void	setZ (double z)
	Sets the point's z-coordinate.

QgsPoint *	simplifyByDistance (double tolerance) const override
	Simplifies the geometry by applying the Douglas Peucker simplification by distance algorithm.

QgsPoint *	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.

void	swapXy () override
	Swaps the x and y coordinates from the geometry.

QgsPoint *	toCurveType () const override
	Returns the geometry converted to the more generic curve type.

QPointF	toQPointF () const
	Returns the point as a QPointF.

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.

void	transformVertices (const std::function< QgsPoint(const QgsPoint &) > &transform) override
	Transforms the vertices from the geometry in place, applying the transform function to every vertex.

double	vertexAngle (QgsVertexId vertex) const override
	Angle undefined.

QgsPoint	vertexAt (QgsVertexId) const override
	Returns the point corresponding to a specified vertex id.

int	vertexCount (int=0, int=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.

int	wkbSize (QgsAbstractGeometry::WkbFlags flags=QgsAbstractGeometry::WkbFlags()) const override
	Returns the length of the QByteArray returned by asWkb()

double	x () const
	Returns the point's x-coordinate.

double	y () const
	Returns the point's y-coordinate.

double	z () const
	Returns the point's z-coordinate.

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.

QString	asJson (int precision=17)
	Returns a GeoJSON representation of the geometry as a QString.

virtual QgsRectangle	boundingBox () const
	Returns the minimal bounding box for the geometry.

virtual QgsPoint	centroid () const
	Returns the centroid of the geometry.

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	hasCurvedSegments () const
	Returns `true` if the geometry contains curved segments.

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 double	length () const
	Returns the planar, 2-dimensional length of 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 QgsAbstractGeometry *	segmentize (double tolerance=M_PI/180., SegmentationToleranceType toleranceType=MaximumAngle) const
	Returns a version of the geometry without curves.

virtual const QgsAbstractGeometry *	simplifiedTypeRef () const
	Returns a reference to the simplest lossless representation of this geometry, e.g.

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 QgsPoint *	cast (const QgsAbstractGeometry *geom)
	Cast the geom to a QgsPoint.

Protected Member Functions
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.

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 QgsAbstractGeometry
virtual QgsRectangle	calculateBoundingBox () const
	Default calculator for the minimal bounding box for the geometry.

virtual QgsBox3D	calculateBoundingBox3D () const
	Calculates the minimal 3D bounding box for the geometry.

virtual QgsAbstractGeometry *	childGeometry (int index) const
	Returns pointer to child geometry (for geometries with child geometries - i.e.

virtual void	clearCache () const
	Clears any cached parameters associated with the geometry, e.g., bounding boxes.

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.

Properties
double	m

double	x

double	y

double	z

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 QgsAbstractGeometry
Qgis::WkbType	mWkbType = Qgis::WkbType::Unknown

Detailed Description

Point geometry type, with support for z-dimension and m-values.

A QgsPoint represents a 2, 3 or 4-dimensional position, with X and Y and optional Z or M coordinates. Since it supports these additional dimensions, QgsPoint is used as the low-level storage of geometry coordinates throughout QGIS.

In some scenarios it is preferable to use the QgsPointXY class instead, which is lighter and has smaller memory requirements compared to QgsPoint. See the QgsPointXY documentation for examples of situations where it is appropriate to use QgsPointXY instead of QgsPoint.

See also: QgsPointXY

Definition at line 48 of file qgspoint.h.

Constructor & Destructor Documentation

◆ QgsPoint() [1/4]

QgsPoint::QgsPoint	(	double	x = `std::numeric_limits<double>::quiet_NaN()`,
		double	y = `std::numeric_limits<double>::quiet_NaN()`,
		double	z = `std::numeric_limits<double>::quiet_NaN()`,
		double	m = `std::numeric_limits<double>::quiet_NaN()`,
		Qgis::WkbType	wkbType = `Qgis::WkbType::Unknown`
	)

Construct a point with the provided initial coordinate values.

If wkbType is set to Qgis::WkbType::Point, Qgis::WkbType::PointZ, Qgis::WkbType::PointM or Qgis::WkbType::PointZM the type will be set accordingly. If it is left to the default Qgis::WkbType::Unknown, the type will be set based on the following rules:

If only x and y are specified, the type will be a 2D point.
If any or both of the Z and M are specified, the appropriate type will be created.

pt = QgsPoint(43.4, 5.3)
pt.asWkt() # Point(43.4 5.3)
 
pt_z = QgsPoint(120, 343, 77)
pt_z.asWkt() # PointZ(120 343 77)
 
pt_m = QgsPoint(33, 88, m=5)
pt_m.m() # 5
pt_m.wkbType() # 2001 (QgsWkbTypes.PointM)
 
pt = QgsPoint(30, 40, wkbType=QgsWkbTypes.PointZ)
pt.z() # nan
pt.wkbType() # 1001 (QgsWkbTypes.PointZ)

Definition at line 41 of file qgspoint.cpp.

◆ QgsPoint() [2/4]

QgsPoint::QgsPoint ( const QgsPointXY & p )

explicit

Construct a QgsPoint from a QgsPointXY object.

Definition at line 65 of file qgspoint.cpp.

◆ QgsPoint() [3/4]

QgsPoint::QgsPoint ( QPointF p )

explicit

Construct a QgsPoint from a QPointF.

Definition at line 79 of file qgspoint.cpp.

◆ QgsPoint() [4/4]

QgsPoint::QgsPoint	(	Qgis::WkbType	wkbType,
		double	x = `std::numeric_limits<double>::quiet_NaN()`,
		double	y = `std::numeric_limits<double>::quiet_NaN()`,
		double	z = `std::numeric_limits<double>::quiet_NaN()`,
		double	m = `std::numeric_limits<double>::quiet_NaN()`
	)

explicit

Create a new point with the given wkbtype and values.

Note: Not available in Python bindings

Definition at line 88 of file qgspoint.cpp.

Member Function Documentation

◆ addMValue()

bool QgsPoint::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

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

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

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

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).

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

id	initial value should be the starting vertex id. The next vertex id will be stored in this variable if found.
vertex	container for found node

QgsPoint QgsPoint::project	(	double	distance,
		double	azimuth,
		double	inclination = `90.0`
	)		const

distance	distance to project
azimuth	angle to project in X Y, clockwise in degrees starting from north
inclination	angle to project in Z (3D). If the point is 2D, the Z value is assumed to be 0.

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)

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.

Public Member Functions

Static Public Member Functions

Protected Member Functions

Properties

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QgsPoint() [1/4]

◆ QgsPoint() [2/4]

◆ QgsPoint() [3/4]

◆ QgsPoint() [4/4]

Member Function Documentation

◆ addMValue()

◆ addZValue()

◆ adjacentVertices()

◆ asGml2()

◆ asGml3()

◆ asJsonObject()

◆ asKml()

◆ asQPainterPath()

◆ asWkb()

◆ asWkt()

◆ azimuth()

◆ boundary()

◆ boundingBox3D()

◆ boundingBoxIntersects() [1/2]

◆ boundingBoxIntersects() [2/2]

◆ cast()

◆ childCount()

◆ childPoint()

◆ clear()

◆ clone()

◆ closestSegment()

◆ compareToSameClass()

◆ convertTo()

◆ coordinateSequence()

◆ createEmptyWithSameType()

◆ deleteVertex()

◆ dimension()

◆ distance() [1/2]

◆ distance() [2/2]

◆ distance3D() [1/2]

◆ distance3D() [2/2]

◆ distanceSquared() [1/2]

◆ distanceSquared() [2/2]

◆ distanceSquared3D() [1/2]

◆ distanceSquared3D() [2/2]

◆ draw()

◆ dropMValue()

◆ dropZValue()

◆ filterVertices()

◆ fromWkb()

◆ fromWkt()

◆ fuzzyDistanceEqual()

◆ fuzzyEqual()

◆ geometryType()

◆ inclination()

◆ insertVertex()

◆ isEmpty()

◆ isValid()

◆ m()

◆ moveVertex()

◆ nCoordinates()

◆ nextVertex()

◆ normalize()

◆ operator!=()

◆ operator+()

◆ operator+=()

◆ operator-() [1/2]

◆ operator-() [2/2]

◆ operator-=()

◆ operator==()

◆ partCount()

◆ project()

Example

◆ removeDuplicateNodes()

◆ ringCount()

◆ rm()

◆ rx()

◆ ry()