QGIS API Documentation  3.23.0-Master (4fd2f04bd0)
QgsGeometryUtils Class Reference

Contains various geometry utility functions. More...

#include <qgsgeometryutils.h>

Classes

struct  SelfIntersection

Public Types

enum  ComponentType { Vertex , Ring , Part }

Static Public Member Functions

static double angleBetweenThreePoints (double x1, double y1, double x2, double y2, double x3, double y3) SIP_HOLDGIL
Calculates the angle between the lines AB and BC, where AB and BC described by points a, b and b, c. More...

static bool angleBisector (double aX, double aY, double bX, double bY, double cX, double cY, double dX, double dY, double &pointX, double &pointY, double &angle) SIP_HOLDGIL
Returns the point (pointX, pointY) forming the bisector from segment (aX aY) (bX bY) and segment (bX, bY) (dX, dY). More...

static bool angleOnCircle (double angle, double angle1, double angle2, double angle3) SIP_HOLDGIL
Returns true if an angle is between angle1 and angle3 on a circle described by angle1, angle2 and angle3. More...

static double averageAngle (double a1, double a2) SIP_HOLDGIL
Averages two angles, correctly handling negative angles and ensuring the result is between 0 and 2 pi. More...

static double averageAngle (double x1, double y1, double x2, double y2, double x3, double y3) SIP_HOLDGIL
Calculates the average angle (in radians) between the two linear segments from (x1, y1) to (x2, y2) and (x2, y2) to (x3, y3). More...

static bool bisector (double aX, double aY, double bX, double bY, double cX, double cY, double &pointX, double &pointY) SIP_HOLDGIL
Returns the point (pointX, pointY) forming the bisector from point (aX, aY) to the segment (bX, bY) (cX, cY). More...

static double ccwAngle (double dy, double dx) SIP_HOLDGIL
Returns the counter clockwise angle between a line with components dx, dy and the line with dx > 0 and dy = 0. More...

static bool circleAngleBetween (double angle, double angle1, double angle2, bool clockwise) SIP_HOLDGIL
Returns true if, in a circle, angle is between angle1 and angle2. More...

static void circleCenterRadius (const QgsPoint &pt1, const QgsPoint &pt2, const QgsPoint &pt3, double &radius, double &centerX, double &centerY) SIP_HOLDGIL
Returns radius and center of the circle through pt1, pt2, pt3. More...

static int circleCircleInnerTangents (const QgsPointXY &center1, double radius1, const QgsPointXY &center2, double radius2, QgsPointXY &line1P1, QgsPointXY &line1P2, QgsPointXY &line2P1, QgsPointXY &line2P2) SIP_HOLDGIL
Calculates the inner tangent points for two circles, centered at center1 and center2 and with radii of radius1 and radius2 respectively. More...

static int circleCircleIntersections (const QgsPointXY &center1, double radius1, const QgsPointXY &center2, double radius2, QgsPointXY &intersection1, QgsPointXY &intersection2) SIP_HOLDGIL
Calculates the intersections points between the circle with center center1 and radius radius1 and the circle with center center2 and radius radius2. More...

static int circleCircleOuterTangents (const QgsPointXY &center1, double radius1, const QgsPointXY &center2, double radius2, QgsPointXY &line1P1, QgsPointXY &line1P2, QgsPointXY &line2P1, QgsPointXY &line2P2) SIP_HOLDGIL
Calculates the outer tangent points for two circles, centered at center1 and center2 and with radii of radius1 and radius2 respectively. More...

static bool circleClockwise (double angle1, double angle2, double angle3) SIP_HOLDGIL
Returns true if the circle defined by three angles is ordered clockwise. More...

static double circleLength (double x1, double y1, double x2, double y2, double x3, double y3) SIP_HOLDGIL
Length of a circular string segment defined by pt1, pt2, pt3. More...

static double circleTangentDirection (const QgsPoint &tangentPoint, const QgsPoint &cp1, const QgsPoint &cp2, const QgsPoint &cp3) SIP_HOLDGIL
Calculates the direction angle of a circle tangent (clockwise from north in radians) More...

static QgsPoint closestPoint (const QgsAbstractGeometry &geometry, const QgsPoint &point)
Returns the nearest point on a segment of a geometry for the specified point. More...

template<class T >
static double closestSegmentFromComponents (T &container, ComponentType ctype, const QgsPoint &pt, QgsPoint &segmentPt, QgsVertexId &vertexAfter, int *leftOf, double epsilon)

static int closestSideOfRectangle (double right, double bottom, double left, double top, double x, double y)
Returns a number representing the closest side of a rectangle defined by /a right, bottom, left, top to the point at (x, y), where the point may be in the interior of the rectangle or outside it. More...

static QgsPoint closestVertex (const QgsAbstractGeometry &geom, const QgsPoint &pt, QgsVertexId &id)
Returns the closest vertex to a geometry for a specified point. More...

static void coefficients (const QgsPoint &pt1, const QgsPoint &pt2, double &a, double &b, double &c) SIP_HOLDGIL
Returns the coefficients (a, b, c for equation "ax + by + c = 0") of a line defined by points pt1 and pt2. More...

static double distanceToVertex (const QgsAbstractGeometry &geom, QgsVertexId id)
Returns the distance along a geometry from its first vertex to the specified vertex. More...

static QVector< QgsLineString * > extractLineStrings (const QgsAbstractGeometry *geom)
Returns list of linestrings extracted from the passed geometry. More...

static double gradient (const QgsPoint &pt1, const QgsPoint &pt2) SIP_HOLDGIL
Returns the gradient of a line defined by points pt1 and pt2. More...

static double interpolateArcValue (double angle, double a1, double a2, double a3, double zm1, double zm2, double zm3) SIP_HOLDGIL
Interpolate a value at given angle on circular arc given values (zm1, zm2, zm3) at three different angles (a1, a2, a3). More...

static QgsPoint interpolatePointOnArc (const QgsPoint &pt1, const QgsPoint &pt2, const QgsPoint &pt3, double distance) SIP_HOLDGIL
Interpolates a point on an arc defined by three points, pt1, pt2 and pt3. More...

static QgsPoint interpolatePointOnLine (const QgsPoint &p1, const QgsPoint &p2, double fraction) SIP_HOLDGIL
Interpolates the position of a point a fraction of the way along the line from p1 to p2. More...

static QgsPointXY interpolatePointOnLine (double x1, double y1, double x2, double y2, double fraction) SIP_HOLDGIL
Interpolates the position of a point a fraction of the way along the line from (x1, y1) to (x2, y2). More...

static QgsPointXY interpolatePointOnLineByValue (double x1, double y1, double v1, double x2, double y2, double v2, double value) SIP_HOLDGIL
Interpolates the position of a point along the line from (x1, y1) to (x2, y2). More...

static int leftOfLine (const double x, const double y, const double x1, const double y1, const double x2, const double y2) SIP_HOLDGIL
Returns a value < 0 if the point (x, y) is left of the line from (x1, y1) -> (x2, y2). More...

static int leftOfLine (const QgsPoint &point, const QgsPoint &p1, const QgsPoint &p2) SIP_HOLDGIL
Returns a value < 0 if the point point is left of the line from p1 -> p2. More...

static double lineAngle (double x1, double y1, double x2, double y2) SIP_HOLDGIL
Calculates the direction of line joining two points in radians, clockwise from the north direction. More...

static bool lineCircleIntersection (const QgsPointXY &center, double radius, const QgsPointXY &linePoint1, const QgsPointXY &linePoint2, QgsPointXY &intersection) SIP_HOLDGIL
Compute the intersection of a line and a circle. More...

static bool lineIntersection (const QgsPoint &p1, QgsVector v1, const QgsPoint &p2, QgsVector v2, QgsPoint &intersection) SIP_HOLDGIL
Computes the intersection between two lines. More...

static double linePerpendicularAngle (double x1, double y1, double x2, double y2) SIP_HOLDGIL
Calculates the perpendicular angle to a line joining two points. More...

static bool linesIntersection3D (const QgsVector3D &La1, const QgsVector3D &La2, const QgsVector3D &Lb1, const QgsVector3D &Lb2, QgsVector3D &intersection) SIP_HOLDGIL
An algorithm to calculate an (approximate) intersection of two lines in 3D. More...

static QgsPoint midpoint (const QgsPoint &pt1, const QgsPoint &pt2) SIP_HOLDGIL
Returns a middle point between points pt1 and pt2. More...

static double normalizedAngle (double angle) SIP_HOLDGIL
Ensures that an angle is in the range 0 <= angle < 2 pi. More...

static void perpendicularCenterSegment (double centerPointX, double centerPointY, double segmentPoint1x, double segmentPoint1y, double segmentPoint2x, double segmentPoint2y, double &perpendicularSegmentPoint1x, double &perpendicularSegmentPoint1y, double &perpendicularSegmentPoint2x, double &perpendicularSegmentPoint2y, double segmentLength=0) SIP_HOLDGIL
Create a perpendicular line segment to a given segment [segmentPoint1,segmentPoint2] with its center at centerPoint. More...

static void perpendicularOffsetPointAlongSegment (double x1, double y1, double x2, double y2, double proportion, double offset, double *x, double *y)
Calculates a point a certain proportion of the way along the segment from (x1, y1) to (x2, y2), offset from the segment by the specified offset amount. More...

static QgsLineString perpendicularSegment (const QgsPoint &p, const QgsPoint &s1, const QgsPoint &s2) SIP_HOLDGIL
Create a perpendicular line segment from p to segment [s1, s2]. More...

static bool pointContinuesArc (const QgsPoint &a1, const QgsPoint &a2, const QgsPoint &a3, const QgsPoint &b, double distanceTolerance, double pointSpacingAngleTolerance) SIP_HOLDGIL
Returns true if point b is on the arc formed by points a1, a2, and a3, but not within that arc portion already described by a1, a2 and a3. More...

static QgsPoint pointOnLineWithDistance (const QgsPoint &startPoint, const QgsPoint &directionPoint, double distance) SIP_HOLDGIL
Returns a point a specified distance toward a second point. More...

static void pointOnLineWithDistance (double x1, double y1, double x2, double y2, double distance, double &x, double &y, double *z1=nullptr, double *z2=nullptr, double *z=nullptr, double *m1=nullptr, double *m2=nullptr, double *m=nullptr)
Calculates the point a specified distance from (x1, y1) toward a second point (x2, y2). More...

static QgsPointSequence pointsFromWKT (const QString &wktCoordinateList, bool is3D, bool isMeasure)
Returns a list of points contained in a WKT string. More...

static QDomElement pointsToGML2 (const QgsPointSequence &points, QDomDocument &doc, int precision, const QString &ns, QgsAbstractGeometry::AxisOrder axisOrder=QgsAbstractGeometry::AxisOrder::XY)
Returns a gml::coordinates DOM element. More...

static QDomElement pointsToGML3 (const QgsPointSequence &points, QDomDocument &doc, int precision, const QString &ns, bool is3D, QgsAbstractGeometry::AxisOrder axisOrder=QgsAbstractGeometry::AxisOrder::XY)
Returns a gml::posList DOM element. More...

static QString pointsToJSON (const QgsPointSequence &points, int precision)
Returns a geoJSON coordinates string. More...

static json pointsToJson (const QgsPointSequence &points, int precision)
Returns coordinates as json object. More...

static void pointsToWKB (QgsWkbPtr &wkb, const QgsPointSequence &points, bool is3D, bool isMeasure)
Returns a LinearRing { uint32 numPoints; Point points[numPoints]; }. More...

static QString pointsToWKT (const QgsPointSequence &points, int precision, bool is3D, bool isMeasure)
Returns a WKT coordinate list. More...

static QgsPoint projectPointOnSegment (const QgsPoint &p, const QgsPoint &s1, const QgsPoint &s2) SIP_HOLDGIL
Project the point on a segment. More...

static bool segmentIntersection (const QgsPoint &p1, const QgsPoint &p2, const QgsPoint &q1, const QgsPoint &q2, QgsPoint &intersectionPoint, bool &isIntersection, double tolerance=1e-8, bool acceptImproperIntersection=false) SIP_HOLDGIL
Compute the intersection between two segments. More...

static void segmentizeArc (const QgsPoint &p1, const QgsPoint &p2, const QgsPoint &p3, QgsPointSequence &points, double tolerance=M_PI_2/90, QgsAbstractGeometry::SegmentationToleranceType toleranceType=QgsAbstractGeometry::MaximumAngle, bool hasZ=false, bool hasM=false)
Convert circular arc defined by p1, p2, p3 (p1/p3 being start resp. More...

static bool segmentMidPoint (const QgsPoint &p1, const QgsPoint &p2, QgsPoint &result, double radius, const QgsPoint &mousePos) SIP_HOLDGIL
Calculates midpoint on circle passing through p1 and p2, closest to the given coordinate mousePos. More...

static QgsPoint segmentMidPointFromCenter (const QgsPoint &p1, const QgsPoint &p2, const QgsPoint &center, bool useShortestArc=true) SIP_HOLDGIL
Calculates the midpoint on the circle passing through p1 and p2, with the specified center coordinate. More...

static int segmentSide (const QgsPoint &pt1, const QgsPoint &pt3, const QgsPoint &pt2) SIP_HOLDGIL
For line defined by points pt1 and pt3, find out on which side of the line is point pt3. More...

static QVector< SelfIntersectionselfIntersections (const QgsAbstractGeometry *geom, int part, int ring, double tolerance)
Find self intersections in a polyline. More...

static Q_DECL_DEPRECATED bool setZValueFromPoints (const QgsPointSequence &points, QgsPoint &point)
A Z dimension is added to point if one of the point in the list points is in 3D. More...

static double skewLinesDistance (const QgsVector3D &P1, const QgsVector3D &P12, const QgsVector3D &P2, const QgsVector3D &P22) SIP_HOLDGIL
An algorithm to calculate the shortest distance between two skew lines. More...

static bool skewLinesProjection (const QgsVector3D &P1, const QgsVector3D &P12, const QgsVector3D &P2, const QgsVector3D &P22, QgsVector3D &X1, double epsilon=0.0001) SIP_HOLDGIL
A method to project one skew line onto another. More...

static double sqrDistance2D (const QgsPoint &pt1, const QgsPoint &pt2) SIP_HOLDGIL
Returns the squared 2D distance between two points. More...

static double sqrDistToLine (double ptX, double ptY, double x1, double y1, double x2, double y2, double &minDistX, double &minDistY, double epsilon) SIP_HOLDGIL
Returns the squared distance between a point and a line. More...

static double sweepAngle (double centerX, double centerY, double x1, double y1, double x2, double y2, double x3, double y3) SIP_HOLDGIL
Calculates angle of a circular string part defined by pt1, pt2, pt3. More...

static bool tangentPointAndCircle (const QgsPointXY &center, double radius, const QgsPointXY &p, QgsPointXY &pt1, QgsPointXY &pt2) SIP_HOLDGIL
Calculates the tangent points between the circle with the specified center and radius and the point p. More...

static bool transferFirstMValueToPoint (const QgsPointSequence &points, QgsPoint &point)
A M dimension is added to point if one of the points in the list points contains an M value. More...

static bool transferFirstZOrMValueToPoint (const QgsGeometry &geom, QgsPoint &point)
A Z or M dimension is added to point if one of the points in the list points contains Z or M value. More...

static bool transferFirstZOrMValueToPoint (const QgsPointSequence &points, QgsPoint &point)
A Z or M dimension is added to point if one of the points in the list points contains Z or M value. More...

template<class Iterator >
static bool transferFirstZOrMValueToPoint (Iterator verticesBegin, Iterator verticesEnd, QgsPoint &point)
A Z or M dimension is added to point if one of the points in the list points contains Z or M value. More...

static bool transferFirstZValueToPoint (const QgsPointSequence &points, QgsPoint &point)
A Z dimension is added to point if one of the point in the list points is in 3D. More...

static double triangleArea (double aX, double aY, double bX, double bY, double cX, double cY) SIP_HOLDGIL
Returns the area of the triangle denoted by the points (aX, aY), (bX, bY) and (cX, cY). More...

static bool verticesAtDistance (const QgsAbstractGeometry &geometry, double distance, QgsVertexId &previousVertex, QgsVertexId &nextVertex)
Retrieves the vertices which are before and after the interpolated point at a specified distance along a linestring (or polygon boundary). More...

static void weightedPointInTriangle (double aX, double aY, double bX, double bY, double cX, double cY, double weightB, double weightC, double &pointX, double &pointY) SIP_HOLDGIL
Returns a weighted point inside the triangle denoted by the points (aX, aY), (bX, bY) and (cX, cY). More...

static QStringList wktGetChildBlocks (const QString &wkt, const QString &defaultType=QString())
Parses a WKT string and returns of list of blocks contained in the WKT. More...

static QPair< QgsWkbTypes::Type, QString > wktReadBlock (const QString &wkt)
Parses a WKT block of the format "TYPE( contents )" and returns a pair of geometry type to contents ("Pair(wkbType, "contents")") More...

Detailed Description

Contains various geometry utility functions.

Since
QGIS 2.10

Definition at line 38 of file qgsgeometryutils.h.

◆ ComponentType

Note
not available in Python bindings
Enumerator
Vertex
Ring
Part

Definition at line 987 of file qgsgeometryutils.h.

◆ angleBetweenThreePoints()

 double QgsGeometryUtils::angleBetweenThreePoints ( double x1, double y1, double x2, double y2, double x3, double y3 )
static

Calculates the angle between the lines AB and BC, where AB and BC described by points a, b and b, c.

Parameters
 x1 x-coordinate of point a y1 y-coordinate of point a x2 x-coordinate of point b y2 y-coordinate of point b x3 x-coordinate of point c y3 y-coordinate of point c
Returns
angle between lines in radians. Returned value is undefined if two or more points are equal.

Definition at line 1632 of file qgsgeometryutils.cpp.

◆ angleBisector()

 bool QgsGeometryUtils::angleBisector ( double aX, double aY, double bX, double bY, double cX, double cY, double dX, double dY, double & pointX, double & pointY, double & angle )
static

Returns the point (pointX, pointY) forming the bisector from segment (aX aY) (bX bY) and segment (bX, bY) (dX, dY).

The bisector segment of AB-CD is (point, projection of point by angle)

Parameters
 aX x-coordinate of first vertex of the segment ab aY y-coordinate of first vertex of the segment ab bX x-coordinate of second vertex of the segment ab bY y-coordinate of second vertex of the segment ab cX x-coordinate of first vertex of the segment cd cY y-coordinate of first vertex of the segment cd dX x-coordinate of second vertex of the segment cd dY y-coordinate of second vertex of the segment cd pointX x-coordinate of generated point pointY y-coordinate of generated point angle angle of the bisector from pointX, pointY origin on [ab-cd]
Returns
true if the bisector exists (A B and C D are not collinear)
Since
QGIS 3.18

Definition at line 1864 of file qgsgeometryutils.cpp.

◆ angleOnCircle()

 bool QgsGeometryUtils::angleOnCircle ( double angle, double angle1, double angle2, double angle3 )
static

Returns true if an angle is between angle1 and angle3 on a circle described by angle1, angle2 and angle3.

Definition at line 766 of file qgsgeometryutils.cpp.

◆ averageAngle() [1/2]

 double QgsGeometryUtils::averageAngle ( double a1, double a2 )
static

Averages two angles, correctly handling negative angles and ensuring the result is between 0 and 2 pi.

Parameters
Returns

Definition at line 1654 of file qgsgeometryutils.cpp.

◆ averageAngle() [2/2]

 double QgsGeometryUtils::averageAngle ( double x1, double y1, double x2, double y2, double x3, double y3 )
static

Calculates the average angle (in radians) between the two linear segments from (x1, y1) to (x2, y2) and (x2, y2) to (x3, y3).

Definition at line 1646 of file qgsgeometryutils.cpp.

◆ bisector()

 bool QgsGeometryUtils::bisector ( double aX, double aY, double bX, double bY, double cX, double cY, double & pointX, double & pointY )
static

Returns the point (pointX, pointY) forming the bisector from point (aX, aY) to the segment (bX, bY) (cX, cY).

The bisector segment of ABC is (A-point)

Parameters
 aX x-coordinate of first vertex in triangle aY y-coordinate of first vertex in triangle bX x-coordinate of second vertex in triangle bY y-coordinate of second vertex in triangle cX x-coordinate of third vertex in triangle cY y-coordinate of third vertex in triangle pointX x-coordinate of generated point pointY y-coordinate of generated point
Returns
true if the bisector exists (A B and C are not collinear)
Since
QGIS 3.18

Definition at line 1883 of file qgsgeometryutils.cpp.

◆ ccwAngle()

 double QgsGeometryUtils::ccwAngle ( double dy, double dx )
static

Returns the counter clockwise angle between a line with components dx, dy and the line with dx > 0 and dy = 0.

Definition at line 676 of file qgsgeometryutils.cpp.

◆ circleAngleBetween()

 bool QgsGeometryUtils::circleAngleBetween ( double angle, double angle1, double angle2, bool clockwise )
static

Returns true if, in a circle, angle is between angle1 and angle2.

Definition at line 740 of file qgsgeometryutils.cpp.

 void QgsGeometryUtils::circleCenterRadius ( const QgsPoint & pt1, const QgsPoint & pt2, const QgsPoint & pt3, double & radius, double & centerX, double & centerY )
static

Returns radius and center of the circle through pt1, pt2, pt3.

Definition at line 690 of file qgsgeometryutils.cpp.

◆ circleCircleInnerTangents()

 int QgsGeometryUtils::circleCircleInnerTangents ( const QgsPointXY & center1, double radius1, const QgsPointXY & center2, double radius2, QgsPointXY & line1P1, QgsPointXY & line1P2, QgsPointXY & line2P1, QgsPointXY & line2P2 )
static

Calculates the inner tangent points for two circles, centered at center1 and center2 and with radii of radius1 and radius2 respectively.

The inner tangent points correspond to the points at which the two lines which are drawn so that they are tangential to both circles and are crossing each other.

The first tangent line is described by the points stored in line1P1 and line1P2, and the second line is described by the points stored in line2P1 and line2P2.

Returns the number of tangents (either 0 or 2).

Since
QGIS 3.6

Definition at line 499 of file qgsgeometryutils.cpp.

◆ circleCircleIntersections()

 int QgsGeometryUtils::circleCircleIntersections ( const QgsPointXY & center1, double radius1, const QgsPointXY & center2, double radius2, QgsPointXY & intersection1, QgsPointXY & intersection2 )
static

If found, the intersection points will be stored in intersection1 and intersection2.

Returns
number of intersection points found.
Since
QGIS 3.2

Definition at line 375 of file qgsgeometryutils.cpp.

◆ circleCircleOuterTangents()

 int QgsGeometryUtils::circleCircleOuterTangents ( const QgsPointXY & center1, double radius1, const QgsPointXY & center2, double radius2, QgsPointXY & line1P1, QgsPointXY & line1P2, QgsPointXY & line2P1, QgsPointXY & line2P2 )
static

Calculates the outer tangent points for two circles, centered at center1 and center2 and with radii of radius1 and radius2 respectively.

The outer tangent points correspond to the points at which the two lines which are drawn so that they are tangential to both circles touch the circles.

The first tangent line is described by the points stored in line1P1 and line1P2, and the second line is described by the points stored in line2P1 and line2P2.

Returns the number of tangents (either 0 or 2).

Since
QGIS 3.2

Definition at line 463 of file qgsgeometryutils.cpp.

◆ circleClockwise()

 bool QgsGeometryUtils::circleClockwise ( double angle1, double angle2, double angle3 )
static

Returns true if the circle defined by three angles is ordered clockwise.

The angles are defined counter-clockwise from the origin, i.e. using Euclidean angles as opposed to geographic "North up" angles.

Definition at line 728 of file qgsgeometryutils.cpp.

◆ circleLength()

 double QgsGeometryUtils::circleLength ( double x1, double y1, double x2, double y2, double x3, double y3 )
static

Length of a circular string segment defined by pt1, pt2, pt3.

Definition at line 772 of file qgsgeometryutils.cpp.

◆ circleTangentDirection()

 double QgsGeometryUtils::circleTangentDirection ( const QgsPoint & tangentPoint, const QgsPoint & cp1, const QgsPoint & cp2, const QgsPoint & cp3 )
static

Calculates the direction angle of a circle tangent (clockwise from north in radians)

Definition at line 870 of file qgsgeometryutils.cpp.

◆ closestPoint()

 QgsPoint QgsGeometryUtils::closestPoint ( const QgsAbstractGeometry & geometry, const QgsPoint & point )
static

Returns the nearest point on a segment of a geometry for the specified point.

The z and m values will be linearly interpolated between the two neighbouring vertices.

Definition at line 101 of file qgsgeometryutils.cpp.

◆ closestSegmentFromComponents()

template<class T >
 static double QgsGeometryUtils::closestSegmentFromComponents ( T & container, ComponentType ctype, const QgsPoint & pt, QgsPoint & segmentPt, QgsVertexId & vertexAfter, int * leftOf, double epsilon )
inlinestatic
Note
not available in Python bindings

Definition at line 995 of file qgsgeometryutils.h.

◆ closestSideOfRectangle()

 int QgsGeometryUtils::closestSideOfRectangle ( double right, double bottom, double left, double top, double x, double y )
static

Returns a number representing the closest side of a rectangle defined by /a right, bottom, left, top to the point at (x, y), where the point may be in the interior of the rectangle or outside it.

The returned value may be:

1. Point is closest to top side of rectangle
2. Point is located on the top-right diagonal of rectangle, equally close to the top and right sides
3. Point is closest to right side of rectangle
4. Point is located on the bottom-right diagonal of rectangle, equally close to the bottom and right sides
5. Point is closest to bottom side of rectangle
6. Point is located on the bottom-left diagonal of rectangle, equally close to the bottom and left sides
7. Point is closest to left side of rectangle
8. Point is located on the top-left diagonal of rectangle, equally close to the top and left sides
Note
This method effectively partitions the space outside of the rectangle into Voronoi cells, so a point to the top left of the rectangle may be assigned to the left or top sides based on its position relative to the diagonal line extended from the rectangle's top-left corner.
Since
QGIS 3.20

Definition at line 1407 of file qgsgeometryutils.cpp.

◆ closestVertex()

 QgsPoint QgsGeometryUtils::closestVertex ( const QgsAbstractGeometry & geom, const QgsPoint & pt, QgsVertexId & id )
static

Returns the closest vertex to a geometry for a specified point.

On error null point will be returned and "id" argument will be invalid.

Definition at line 67 of file qgsgeometryutils.cpp.

◆ coefficients()

 void QgsGeometryUtils::coefficients ( const QgsPoint & pt1, const QgsPoint & pt2, double & a, double & b, double & c )
static

Returns the coefficients (a, b, c for equation "ax + by + c = 0") of a line defined by points pt1 and pt2.

Parameters
 pt1 first point. pt2 second point. a Output parameter, a coefficient of the equation. b Output parameter, b coefficient of the equation. c Output parameter, c coefficient of the equation.
Since
QGIS 3.0

Definition at line 1547 of file qgsgeometryutils.cpp.

◆ distanceToVertex()

 double QgsGeometryUtils::distanceToVertex ( const QgsAbstractGeometry & geom, QgsVertexId id )
static

Returns the distance along a geometry from its first vertex to the specified vertex.

Parameters
 geom geometry id vertex id to find distance to
Returns
distance to vertex (following geometry)
Since
QGIS 2.16

Definition at line 134 of file qgsgeometryutils.cpp.

◆ extractLineStrings()

 QVector< QgsLineString * > QgsGeometryUtils::extractLineStrings ( const QgsAbstractGeometry * geom )
static

Returns list of linestrings extracted from the passed geometry.

The returned objects have to be deleted by the caller.

Definition at line 31 of file qgsgeometryutils.cpp.

 double QgsGeometryUtils::gradient ( const QgsPoint & pt1, const QgsPoint & pt2 )
static

Returns the gradient of a line defined by points pt1 and pt2.

Parameters
 pt1 first point. pt2 second point.
Returns
The gradient of this linear entity, or infinity if vertical
Since
QGIS 3.0

Definition at line 1535 of file qgsgeometryutils.cpp.

◆ interpolateArcValue()

 double QgsGeometryUtils::interpolateArcValue ( double angle, double a1, double a2, double a3, double zm1, double zm2, double zm3 )
static

Interpolate a value at given angle on circular arc given values (zm1, zm2, zm3) at three different angles (a1, a2, a3).

Since
3.0

Definition at line 1096 of file qgsgeometryutils.cpp.

◆ interpolatePointOnArc()

 QgsPoint QgsGeometryUtils::interpolatePointOnArc ( const QgsPoint & pt1, const QgsPoint & pt2, const QgsPoint & pt3, double distance )
static

Interpolates a point on an arc defined by three points, pt1, pt2 and pt3.

The arc will be interpolated by the specified distance from pt1.

Any z or m values present in the points will also be linearly interpolated in the output.

Since
QGIS 3.4

Definition at line 651 of file qgsgeometryutils.cpp.

◆ interpolatePointOnLine() [1/2]

 QgsPoint QgsGeometryUtils::interpolatePointOnLine ( const QgsPoint & p1, const QgsPoint & p2, double fraction )
static

Interpolates the position of a point a fraction of the way along the line from p1 to p2.

Usually the fraction should be between 0 and 1, where 0 represents the point at the start of the line (p1) and 1 represents the end of the line (p2). However, it is possible to use a fraction < 0 or > 1, in which case the returned point is extrapolated from the supplied line.

Any Z or M values present in the input points will also be interpolated and present in the returned point.

interpolatePointOnLineByValue()
Since
QGIS 3.0.2

Definition at line 1509 of file qgsgeometryutils.cpp.

◆ interpolatePointOnLine() [2/2]

 QgsPointXY QgsGeometryUtils::interpolatePointOnLine ( double x1, double y1, double x2, double y2, double fraction )
static

Interpolates the position of a point a fraction of the way along the line from (x1, y1) to (x2, y2).

Usually the fraction should be between 0 and 1, where 0 represents the point at the start of the line (x1, y1) and 1 represents the end of the line (x2, y2). However, it is possible to use a fraction < 0 or > 1, in which case the returned point is extrapolated from the supplied line.

interpolatePointOnLineByValue()
Since
QGIS 3.0.2

Definition at line 1519 of file qgsgeometryutils.cpp.

◆ interpolatePointOnLineByValue()

 QgsPointXY QgsGeometryUtils::interpolatePointOnLineByValue ( double x1, double y1, double v1, double x2, double y2, double v2, double value )
static

Interpolates the position of a point along the line from (x1, y1) to (x2, y2).

The position is interpolated using a supplied target value and the value at the start of the line (v1) and end of the line (v2). The returned point will be linearly interpolated to match position corresponding to the target value.

interpolatePointOnLine()
Since
QGIS 3.0.2

Definition at line 1526 of file qgsgeometryutils.cpp.

◆ leftOfLine() [1/2]

 int QgsGeometryUtils::leftOfLine ( const double x, const double y, const double x1, const double y1, const double x2, const double y2 )
static

Returns a value < 0 if the point (x, y) is left of the line from (x1, y1) -> (x2, y2).

A positive return value indicates the point is to the right of the line.

If the return value is 0, then the test was unsuccessful (e.g. due to testing a point exactly on the line, or exactly in line with the segment) and the result is undefined.

Definition at line 589 of file qgsgeometryutils.cpp.

◆ leftOfLine() [2/2]

 int QgsGeometryUtils::leftOfLine ( const QgsPoint & point, const QgsPoint & p1, const QgsPoint & p2 )
static

Returns a value < 0 if the point point is left of the line from p1 -> p2.

A positive return value indicates the point is to the right of the line.

If the return value is 0, then the test was unsuccessful (e.g. due to testing a point exactly on the line, or exactly in line with the segment) and the result is undefined.

Since
QGIS 3.6

Definition at line 584 of file qgsgeometryutils.cpp.

◆ lineAngle()

 double QgsGeometryUtils::lineAngle ( double x1, double y1, double x2, double y2 )
static

Calculates the direction of line joining two points in radians, clockwise from the north direction.

Parameters
 x1 x-coordinate of line start y1 y-coordinate of line start x2 x-coordinate of line end y2 y-coordinate of line end
Returns
angle in radians. Returned value is undefined if start and end point are the same.

Definition at line 1625 of file qgsgeometryutils.cpp.

◆ lineCircleIntersection()

 bool QgsGeometryUtils::lineCircleIntersection ( const QgsPointXY & center, double radius, const QgsPointXY & linePoint1, const QgsPointXY & linePoint2, QgsPointXY & intersection )
static

Compute the intersection of a line and a circle.

If the intersection has two solutions (points), the closest point to the initial intersection point is returned.

Parameters
 center the center of the circle radius the radius of the circle linePoint1 a first point on the line linePoint2 a second point on the line intersection the initial point and the returned intersection point
Returns
true if an intersection has been found

Definition at line 321 of file qgsgeometryutils.cpp.

◆ lineIntersection()

 bool QgsGeometryUtils::lineIntersection ( const QgsPoint & p1, QgsVector v1, const QgsPoint & p2, QgsVector v2, QgsPoint & intersection )
static

Computes the intersection between two lines.

Z dimension is supported and is retrieved from the first 3D point amongst p1 and p2.

Parameters
 p1 Point on the first line v1 Direction vector of the first line p2 Point on the second line v2 Direction vector of the second line intersection Output parameter, the intersection point
Returns
Whether the lines intersect

Definition at line 242 of file qgsgeometryutils.cpp.

◆ linePerpendicularAngle()

 double QgsGeometryUtils::linePerpendicularAngle ( double x1, double y1, double x2, double y2 )
static

Calculates the perpendicular angle to a line joining two points.

Returned angle is in radians, clockwise from the north direction.

Parameters
 x1 x-coordinate of line start y1 y-coordinate of line start x2 x-coordinate of line end y2 y-coordinate of line end
Returns
angle in radians. Returned value is undefined if start and end point are the same.

Definition at line 1639 of file qgsgeometryutils.cpp.

◆ linesIntersection3D()

 bool QgsGeometryUtils::linesIntersection3D ( const QgsVector3D & La1, const QgsVector3D & La2, const QgsVector3D & Lb1, const QgsVector3D & Lb2, QgsVector3D & intersection )
static

An algorithm to calculate an (approximate) intersection of two lines in 3D.

Parameters
 La1 is the first point on the first line, La2 is the second point on the first line, Lb1 is the first point on the second line, Lb2 is the second point on the second line, intersection is the result intersection, of it can be found.
Returns
true if the intersection can be found, false - otherwise.

Example

# (True, PyQt5.QtGui.QgsVector3D(2.0, 0.0, 0.0))
# (True, PyQt5.QtGui.QgsVector3D(2.0, 0.0, 0.0))
# (True, PyQt5.QtGui.QgsVector3D(0.0, 0.0, 0.0))
# (True, PyQt5.QtGui.QgsVector3D(0.0, 0.0, 0.0))
# (False, PyQt5.QtGui.QgsVector3D(0.0, 0.0, 0.0))
# (False, PyQt5.QtGui.QgsVector3D(0.0, 0.0, 0.0))
# (True, PyQt5.QtGui.QgsVector3D(3.0, 3.0, 0.0))
# (True, PyQt5.QtGui.QgsVector3D(3.0, 3.0, 0.0))
# (True, PyQt5.QtGui.QgsVector3D(2.5, 2.5, 2.5))
# (True, PyQt5.QtGui.QgsVector3D(2.5, 2.5, 2.5))
# (True, PyQt5.QtGui.QgsVector3D(0.0, 5.0, 5.0))
static bool linesIntersection3D(const QgsVector3D &La1, const QgsVector3D &La2, const QgsVector3D &Lb1, const QgsVector3D &Lb2, QgsVector3D &intersection) SIP_HOLDGIL
An algorithm to calculate an (approximate) intersection of two lines in 3D.

Definition at line 1735 of file qgsgeometryutils.cpp.

◆ midpoint()

 QgsPoint QgsGeometryUtils::midpoint ( const QgsPoint & pt1, const QgsPoint & pt2 )
static

Returns a middle point between points pt1 and pt2.

Z value is computed if one of this point have Z. M value is computed if one of this point have M.

Parameters
 pt1 first point. pt2 second point.
Returns
New point at middle between points pt1 and pt2.

Example

p = QgsPoint( 4, 6 ) # 2D point
pr = midpoint ( p, QgsPoint( 2, 2 ) )
# pr is a 2D point: 'Point (3 4)'
pr = midpoint ( p, QgsPoint( QgsWkbTypes.PointZ, 2, 2, 2 ) )
# pr is a 3D point: 'PointZ (3 4 1)'
pr = midpoint ( p, QgsPoint( QgsWkbTypes.PointM, 2, 2, 0, 2 ) )
# pr is a 3D point: 'PointM (3 4 1)'
pr = midpoint ( p, QgsPoint( QgsWkbTypes.PointZM, 2, 2, 2, 2 ) )
# pr is a 3D point: 'PointZM (3 4 1 1)'
Point geometry type, with support for z-dimension and m-values.
Definition: qgspoint.h:49
Since
QGIS 3.0

Definition at line 1484 of file qgsgeometryutils.cpp.

◆ normalizedAngle()

 double QgsGeometryUtils::normalizedAngle ( double angle )
static

Ensures that an angle is in the range 0 <= angle < 2 pi.

Parameters
Returns
equivalent angle within the range [0, 2 pi)

Definition at line 1321 of file qgsgeometryutils.cpp.

◆ perpendicularCenterSegment()

 void QgsGeometryUtils::perpendicularCenterSegment ( double centerPointX, double centerPointY, double segmentPoint1x, double segmentPoint1y, double segmentPoint2x, double segmentPoint2y, double & perpendicularSegmentPoint1x, double & perpendicularSegmentPoint1y, double & perpendicularSegmentPoint2x, double & perpendicularSegmentPoint2y, double segmentLength = 0 )
static

Create a perpendicular line segment to a given segment [segmentPoint1,segmentPoint2] with its center at centerPoint.

May be used to split geometries. Unless segmentLength is specified the new centered perpendicular line segment will have double the length of the input segment.

The result is a line (segment) centered in point p and perpendicular to segment [segmentPoint1, segmentPoint2].

Parameters
 centerPointX x-coordinate of the point where the center of the perpendicular should be located centerPointY y-coordinate of the point where the center of the perpendicular should be located segmentPoint1x x-coordinate of segmentPoint1, the segment's start point segmentPoint1y y-coordinate of segmentPoint1, the segment's start point segmentPoint2x x-coordinate of segmentPoint2, the segment's end point segmentPoint2y y-coordinate of segmentPoint2, the segment's end point perpendicularSegmentPoint1x x-coordinate of the perpendicularCenterSegment's start point perpendicularSegmentPoint1y y-coordinate of the perpendicularCenterSegment's start point perpendicularSegmentPoint2x x-coordinate of the perpendicularCenterSegment's end point perpendicularSegmentPoint2y y-coordinate of the perpendicularCenterSegment's end point segmentLength (optional) Trims to given length. A segmentLength value of 0 refers to the default length which is double the length of the input segment. Set to 1 for a normalized length.
Since
QGIS 3.24

Definition at line 1608 of file qgsgeometryutils.cpp.

◆ perpendicularOffsetPointAlongSegment()

 void QgsGeometryUtils::perpendicularOffsetPointAlongSegment ( double x1, double y1, double x2, double y2, double proportion, double offset, double * x, double * y )
static

Calculates a point a certain proportion of the way along the segment from (x1, y1) to (x2, y2), offset from the segment by the specified offset amount.

Parameters
 x1 x-coordinate of start of segment y1 y-coordinate of start of segment x2 x-coordinate of end of segment y2 y-coordinate of end of segment proportion proportion of the segment's length at which to place the point (between 0.0 and 1.0) offset perpendicular offset from segment to apply to point. A negative offset shifts the point to the left of the segment, while a positive offset will shift it to the right of the segment. x calculated point x-coordinate y calculated point y-coordinate

Example

# Offset point at center of segment by 2 units to the right
# (6.0, 3.0)
# Offset point at center of segment by 2 units to the left
# (6.0, 7.0)
static void perpendicularOffsetPointAlongSegment(double x1, double y1, double x2, double y2, double proportion, double offset, double *x, double *y)
Calculates a point a certain proportion of the way along the segment from (x1, y1) to (x2,...
Since
QGIS 3.20

Definition at line 634 of file qgsgeometryutils.cpp.

◆ perpendicularSegment()

 QgsLineString QgsGeometryUtils::perpendicularSegment ( const QgsPoint & p, const QgsPoint & s1, const QgsPoint & s2 )
static

Create a perpendicular line segment from p to segment [s1, s2].

Parameters
 p The point s1 The segment start point s2 The segment end point
Returns
A line (segment) from p to perpendicular point on segment [s1, s2]

Definition at line 1570 of file qgsgeometryutils.cpp.

◆ pointContinuesArc()

 bool QgsGeometryUtils::pointContinuesArc ( const QgsPoint & a1, const QgsPoint & a2, const QgsPoint & a3, const QgsPoint & b, double distanceTolerance, double pointSpacingAngleTolerance )
static

Returns true if point b is on the arc formed by points a1, a2, and a3, but not within that arc portion already described by a1, a2 and a3.

The distanceTolerance specifies the maximum deviation allowed between the original location of point and where it would fall on the candidate arc.

This method only consider a segments as continuing an arc if the points are all regularly spaced on the candidate arc. The pointSpacingAngleTolerance parameter specifies the maximum angular deviation (in radians) allowed when testing for regular point spacing.

Note
The API is considered EXPERIMENTAL and can be changed without a notice
Since
QGIS 3.14

Definition at line 895 of file qgsgeometryutils.cpp.

◆ pointOnLineWithDistance() [1/2]

 QgsPoint QgsGeometryUtils::pointOnLineWithDistance ( const QgsPoint & startPoint, const QgsPoint & directionPoint, double distance )
static

Returns a point a specified distance toward a second point.

Definition at line 600 of file qgsgeometryutils.cpp.

◆ pointOnLineWithDistance() [2/2]

 void QgsGeometryUtils::pointOnLineWithDistance ( double x1, double y1, double x2, double y2, double distance, double & x, double & y, double * z1 = nullptr, double * z2 = nullptr, double * z = nullptr, double * m1 = nullptr, double * m2 = nullptr, double * m = nullptr )
static

Calculates the point a specified distance from (x1, y1) toward a second point (x2, y2).

Optionally, interpolated z and m values can be obtained by specifying the z1, z2 and z arguments and/or the m1, m2, m arguments.

Note
Not available in Python bindings
Since
QGIS 3.4

Definition at line 607 of file qgsgeometryutils.cpp.

◆ pointsFromWKT()

 QgsPointSequence QgsGeometryUtils::pointsFromWKT ( const QString & wktCoordinateList, bool is3D, bool isMeasure )
static

Returns a list of points contained in a WKT string.

Note
not available in Python bindings

Definition at line 1116 of file qgsgeometryutils.cpp.

◆ pointsToGML2()

 QDomElement QgsGeometryUtils::pointsToGML2 ( const QgsPointSequence & points, QDomDocument & doc, int precision, const QString & ns, QgsAbstractGeometry::AxisOrder axisOrder = QgsAbstractGeometry::AxisOrder::XY )
static

Returns a gml::coordinates DOM element.

Note
not available in Python bindings

Definition at line 1239 of file qgsgeometryutils.cpp.

◆ pointsToGML3()

 QDomElement QgsGeometryUtils::pointsToGML3 ( const QgsPointSequence & points, QDomDocument & doc, int precision, const QString & ns, bool is3D, QgsAbstractGeometry::AxisOrder axisOrder = QgsAbstractGeometry::AxisOrder::XY )
static

Returns a gml::posList DOM element.

Note
not available in Python bindings

Definition at line 1266 of file qgsgeometryutils.cpp.

◆ pointsToJSON()

 QString QgsGeometryUtils::pointsToJSON ( const QgsPointSequence & points, int precision )
static

Returns a geoJSON coordinates string.

Note
not available in Python bindings

Definition at line 1288 of file qgsgeometryutils.cpp.

◆ pointsToJson()

 json QgsGeometryUtils::pointsToJson ( const QgsPointSequence & points, int precision )
static

Returns coordinates as json object.

Note
not available in Python bindings

Definition at line 1304 of file qgsgeometryutils.cpp.

◆ pointsToWKB()

 void QgsGeometryUtils::pointsToWKB ( QgsWkbPtr & wkb, const QgsPointSequence & points, bool is3D, bool isMeasure )
static

Returns a LinearRing { uint32 numPoints; Point points[numPoints]; }.

Note
not available in Python bindings

Definition at line 1203 of file qgsgeometryutils.cpp.

◆ pointsToWKT()

 QString QgsGeometryUtils::pointsToWKT ( const QgsPointSequence & points, int precision, bool is3D, bool isMeasure )
static

Returns a WKT coordinate list.

Note
not available in Python bindings

Definition at line 1220 of file qgsgeometryutils.cpp.

◆ projectPointOnSegment()

 static QgsPoint QgsGeometryUtils::projectPointOnSegment ( const QgsPoint & p, const QgsPoint & s1, const QgsPoint & s2 )
inlinestatic

Project the point on a segment.

Parameters
 p The point s1 The segment start point s2 The segment end point
Returns
The projection of the point on the segment

Definition at line 239 of file qgsgeometryutils.h.

◆ segmentIntersection()

 bool QgsGeometryUtils::segmentIntersection ( const QgsPoint & p1, const QgsPoint & p2, const QgsPoint & q1, const QgsPoint & q2, QgsPoint & intersectionPoint, bool & isIntersection, double tolerance = 1e-8, bool acceptImproperIntersection = false )
static

Compute the intersection between two segments.

Parameters
 p1 First segment start point p2 First segment end point q1 Second segment start point q2 Second segment end point intersectionPoint Output parameter, the intersection point isIntersection Output parameter, return true if an intersection is found tolerance The tolerance to use acceptImproperIntersection By default, this method returns true only if segments have proper intersection. If set true, returns also TRUE if segments have improper intersection (end of one segment on other segment ; continuous segments).
Returns
Whether the segments intersect

Example

ret = QgsGeometryUtils.segmentIntersection( QgsPoint( 0, 0 ), QgsPoint( 0, 1 ), QgsPoint( 1, 1 ), QgsPoint( 1, 0 ) )
ret, ret.asWkt(), ret
# Whether the segments intersect, the intersection point, is intersect
# (False, 'Point (0 0)', False)
ret = QgsGeometryUtils.segmentIntersection( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 0, 5 ), QgsPoint( 1, 5 ) )
ret, ret.asWkt(), ret
# (False, 'Point (0 5)', True)
ret = QgsGeometryUtils.segmentIntersection( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 0, 5 ), QgsPoint( 1, 5 ), acceptImproperIntersection=True )
ret, ret.asWkt(), ret
# (True, 'Point (0 5)', True)
ret = QgsGeometryUtils.segmentIntersection( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 0, 2 ), QgsPoint( 1, 5 ) )
ret, ret.asWkt(), ret
# (False, 'Point (0 2)', True)
ret = QgsGeometryUtils.segmentIntersection( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 0, 2 ), QgsPoint( 1, 5 ), acceptImproperIntersection=True )
ret, ret.asWkt(), ret
# (True, 'Point (0 2)', True)
ret = QgsGeometryUtils.segmentIntersection( QgsPoint( 0, -5 ), QgsPoint( 0, 5 ), QgsPoint( 2, 0 ), QgsPoint( -1, 0 ) )
ret, ret.asWkt(), ret
# (True, 'Point (0 0)', True)
static bool segmentIntersection(const QgsPoint &p1, const QgsPoint &p2, const QgsPoint &q1, const QgsPoint &q2, QgsPoint &intersectionPoint, bool &isIntersection, double tolerance=1e-8, bool acceptImproperIntersection=false) SIP_HOLDGIL
Compute the intersection between two segments.

Definition at line 261 of file qgsgeometryutils.cpp.

◆ segmentizeArc()

 void QgsGeometryUtils::segmentizeArc ( const QgsPoint & p1, const QgsPoint & p2, const QgsPoint & p3, QgsPointSequence & points, double tolerance = M_PI_2 / 90, QgsAbstractGeometry::SegmentationToleranceType toleranceType = QgsAbstractGeometry::MaximumAngle, bool hasZ = false, bool hasM = false )
static

Convert circular arc defined by p1, p2, p3 (p1/p3 being start resp.

end point, p2 lies on the arc) into a sequence of points.

Since
3.0

Definition at line 954 of file qgsgeometryutils.cpp.

◆ segmentMidPoint()

 bool QgsGeometryUtils::segmentMidPoint ( const QgsPoint & p1, const QgsPoint & p2, QgsPoint & result, double radius, const QgsPoint & mousePos )
static

Calculates midpoint on circle passing through p1 and p2, closest to the given coordinate mousePos.

Z dimension is supported and is retrieved from the first 3D point amongst p1 and p2.

segmentMidPointFromCenter()

Definition at line 814 of file qgsgeometryutils.cpp.

◆ segmentMidPointFromCenter()

 QgsPoint QgsGeometryUtils::segmentMidPointFromCenter ( const QgsPoint & p1, const QgsPoint & p2, const QgsPoint & center, bool useShortestArc = true )
static

Calculates the midpoint on the circle passing through p1 and p2, with the specified center coordinate.

If useShortestArc is true, then the midpoint returned will be that corresponding to the shorter arc from p1 to p2. If it is false, the longer arc from p1 to p2 will be used (i.e. winding the other way around the circle).

segmentMidPoint()
Since
QGIS 3.2

Definition at line 861 of file qgsgeometryutils.cpp.

◆ segmentSide()

 int QgsGeometryUtils::segmentSide ( const QgsPoint & pt1, const QgsPoint & pt3, const QgsPoint & pt2 )
static

For line defined by points pt1 and pt3, find out on which side of the line is point pt3.

Returns -1 if pt3 on the left side, 1 if pt3 is on the right side or 0 if pt3 lies on the line.

Since
3.0

Definition at line 1075 of file qgsgeometryutils.cpp.

◆ selfIntersections()

 QVector< QgsGeometryUtils::SelfIntersection > QgsGeometryUtils::selfIntersections ( const QgsAbstractGeometry * geom, int part, int ring, double tolerance )
static

Find self intersections in a polyline.

Parameters
 geom The geometry to check part The part of the geometry to check ring The ring of the geometry part to check tolerance The tolerance to use
Returns
The list of self intersections
Note
not available in Python bindings
Since
QGIS 2.12

Definition at line 544 of file qgsgeometryutils.cpp.

◆ setZValueFromPoints()

 static Q_DECL_DEPRECATED bool QgsGeometryUtils::setZValueFromPoints ( const QgsPointSequence & points, QgsPoint & point )
inlinestatic

A Z dimension is added to point if one of the point in the list points is in 3D.

Moreover, the Z value of point is updated with the first Z value found in list points even if point already contains a Z value.

Parameters
 points List of points in which a 3D point is searched. point The point to update with Z dimension and value.
Returns
true if the point is updated, false otherwise
Warning
This method does not copy the z value of the coordinate from the points whose z value is closest to the original x/y point, but only the first one found.
Since
QGIS 3.0
Deprecated:
since QGIS 3.20 use transferFirstZValueToPoint( const QgsPointSequence &points, QgsPoint &point ) instead

Definition at line 818 of file qgsgeometryutils.h.

◆ skewLinesDistance()

 double QgsGeometryUtils::skewLinesDistance ( const QgsVector3D & P1, const QgsVector3D & P12, const QgsVector3D & P2, const QgsVector3D & P22 )
static

An algorithm to calculate the shortest distance between two skew lines.

Parameters
 P1 is the first point of the first line, P12 is the second point on the first line, P2 is the first point on the second line, P22 is the second point on the second line.
Returns
the shortest distance

Definition at line 1681 of file qgsgeometryutils.cpp.

◆ skewLinesProjection()

 bool QgsGeometryUtils::skewLinesProjection ( const QgsVector3D & P1, const QgsVector3D & P12, const QgsVector3D & P2, const QgsVector3D & P22, QgsVector3D & X1, double epsilon = 0.0001 )
static

A method to project one skew line onto another.

Parameters
 P1 is a first point that belonds to first skew line, P12 is the second point that belongs to first skew line, P2 is the first point that belongs to second skew line, P22 is the second point that belongs to second skew line, X1 is the result projection point of line P2P22 onto line P1P12, epsilon the tolerance to use.
Returns
true if such point exists, false - otherwise.

Definition at line 1693 of file qgsgeometryutils.cpp.

◆ sqrDistance2D()

 double QgsGeometryUtils::sqrDistance2D ( const QgsPoint & pt1, const QgsPoint & pt2 )
static

Returns the squared 2D distance between two points.

Definition at line 198 of file qgsgeometryutils.cpp.

◆ sqrDistToLine()

 double QgsGeometryUtils::sqrDistToLine ( double ptX, double ptY, double x1, double y1, double x2, double y2, double & minDistX, double & minDistY, double epsilon )
static

Returns the squared distance between a point and a line.

Definition at line 203 of file qgsgeometryutils.cpp.

◆ sweepAngle()

 double QgsGeometryUtils::sweepAngle ( double centerX, double centerY, double x1, double y1, double x2, double y2, double x3, double y3 )
static

Calculates angle of a circular string part defined by pt1, pt2, pt3.

Definition at line 784 of file qgsgeometryutils.cpp.

◆ tangentPointAndCircle()

 bool QgsGeometryUtils::tangentPointAndCircle ( const QgsPointXY & center, double radius, const QgsPointXY & p, QgsPointXY & pt1, QgsPointXY & pt2 )
static

Calculates the tangent points between the circle with the specified center and radius and the point p.

If found, the tangent points will be stored in pt1 and pt2.

Since
QGIS 3.2

Definition at line 439 of file qgsgeometryutils.cpp.

◆ transferFirstMValueToPoint()

 bool QgsGeometryUtils::transferFirstMValueToPoint ( const QgsPointSequence & points, QgsPoint & point )
static

A M dimension is added to point if one of the points in the list points contains an M value.

Moreover, the M value of point is updated with the first M value found in list points even if point already contains a M value.

Parameters
 points List of points in which a M point is searched. point The point to update with M dimension and value.
Returns
true if the point is updated, false otherwise
Warning
This method does not copy the m value of the coordinate from the points whose m value is closest to the original x/y point, but only the first one found.
Since
QGIS 3.20

Definition at line 1828 of file qgsgeometryutils.cpp.

◆ transferFirstZOrMValueToPoint() [1/3]

 static bool QgsGeometryUtils::transferFirstZOrMValueToPoint ( const QgsGeometry & geom, QgsPoint & point )
inlinestatic

A Z or M dimension is added to point if one of the points in the list points contains Z or M value.

This method is equivalent to successively calling Z and M but avoiding looping twice over the set of points.

Parameters
 geom geometry in which a M point is searched. point The point to update with Z or M dimension and value.
Returns
true if the point is updated, false otherwise
Warning
This method does not copy the z or m value of the coordinate from the points whose z or m value is closest to the original x/y point, but only the first one found.
Since
QGIS 3.20

Definition at line 938 of file qgsgeometryutils.h.

◆ transferFirstZOrMValueToPoint() [2/3]

 static bool QgsGeometryUtils::transferFirstZOrMValueToPoint ( const QgsPointSequence & points, QgsPoint & point )
inlinestatic

A Z or M dimension is added to point if one of the points in the list points contains Z or M value.

This method is equivalent to successively calling Z and M but avoiding looping twice over the set of points.

Parameters
 points List of points in which a M point is searched. point The point to update with Z or M dimension and value.
Returns
true if the point is updated, false otherwise
Warning
This method does not copy the z or m value of the coordinate from the points whose z or m value is closest to the original x/y point, but only the first one found.
Since
QGIS 3.20

Definition at line 917 of file qgsgeometryutils.h.

◆ transferFirstZOrMValueToPoint() [3/3]

template<class Iterator >
 static bool QgsGeometryUtils::transferFirstZOrMValueToPoint ( Iterator verticesBegin, Iterator verticesEnd, QgsPoint & point )
inlinestatic

A Z or M dimension is added to point if one of the points in the list points contains Z or M value.

This method is equivalent to successively calling Z and M but avoiding looping twice over the set of points.

Parameters
 verticesBegin begin vertex which a Z or M point is searched. verticesEnd end vertex which a Z or M point is searched. point The point to update with Z or M dimension and value.
Returns
true if the point is updated, false otherwise
Warning
This method does not copy the z or m value of the coordinate from the points whose z or m value is closest to the original x/y point, but only the first one found.
Note
Not available in Python bindings
Since
QGIS 3.20

Definition at line 875 of file qgsgeometryutils.h.

◆ transferFirstZValueToPoint()

 bool QgsGeometryUtils::transferFirstZValueToPoint ( const QgsPointSequence & points, QgsPoint & point )
static

A Z dimension is added to point if one of the point in the list points is in 3D.

Moreover, the Z value of point is updated with the first Z value found in list points even if point already contains a Z value.

Parameters
 points List of points in which a 3D point is searched. point The point to update with Z dimension and value.
Returns
true if the point is updated, false otherwise
Warning
This method does not copy the z value of the coordinate from the points whose z value is closest to the original x/y point, but only the first one found.
Since
QGIS 3.20

Definition at line 1846 of file qgsgeometryutils.cpp.

◆ triangleArea()

 double QgsGeometryUtils::triangleArea ( double aX, double aY, double bX, double bY, double cX, double cY )
static

Returns the area of the triangle denoted by the points (aX, aY), (bX, bY) and (cX, cY).

Since
QGIS 3.10

Definition at line 1804 of file qgsgeometryutils.cpp.

◆ verticesAtDistance()

 bool QgsGeometryUtils::verticesAtDistance ( const QgsAbstractGeometry & geometry, double distance, QgsVertexId & previousVertex, QgsVertexId & nextVertex )
static

Retrieves the vertices which are before and after the interpolated point at a specified distance along a linestring (or polygon boundary).

Parameters
 geometry line or polygon geometry distance distance to traverse along geometry previousVertex will be set to previous vertex ID nextVertex will be set to next vertex ID
Returns
true if vertices were successfully retrieved
Note
if the distance coincides exactly with a vertex, then both previousVertex and nextVertex will be set to this vertex
Since
QGIS 3.0

Definition at line 153 of file qgsgeometryutils.cpp.

◆ weightedPointInTriangle()

 void QgsGeometryUtils::weightedPointInTriangle ( double aX, double aY, double bX, double bY, double cX, double cY, double weightB, double weightC, double & pointX, double & pointY )
static

Returns a weighted point inside the triangle denoted by the points (aX, aY), (bX, bY) and (cX, cY).

Parameters
 aX x-coordinate of first vertex in triangle aY y-coordinate of first vertex in triangle bX x-coordinate of second vertex in triangle bY y-coordinate of second vertex in triangle cX x-coordinate of third vertex in triangle cY y-coordinate of third vertex in triangle weightB weighting factor along axis A-B (between 0 and 1) weightC weighting factor along axis A-C (between 0 and 1) pointX x-coordinate of generated point pointY y-coordinate of generated point
Since
QGIS 3.10

Definition at line 1809 of file qgsgeometryutils.cpp.

◆ wktGetChildBlocks()

 QStringList QgsGeometryUtils::wktGetChildBlocks ( const QString & wkt, const QString & defaultType = QString() )
static

Parses a WKT string and returns of list of blocks contained in the WKT.

Parameters
 wkt WKT string in the format "TYPE1 (contents1), TYPE2 (TYPE3 (contents3), TYPE4 (contents4))" defaultType default geometry type for children
Returns
list of WKT child block strings, e.g., List("TYPE1 (contents1)", "TYPE2 (TYPE3 (contents3), TYPE4 (contents4))")
Note
not available in Python bindings

Definition at line 1367 of file qgsgeometryutils.cpp.