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QGIS API Documentation
3.6.0-Noosa (5873452)
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A geometry is the spatial representation of a feature. More...
#include <qgsgeometry.h>
Classes | |
| class | Error |
Public Types | |
| enum | BufferSide { SideLeft = 0, SideRight } |
| Side of line to buffer. More... | |
| enum | EndCapStyle { CapRound = 1, CapFlat, CapSquare } |
| End cap styles for buffers. More... | |
| enum | JoinStyle { JoinStyleRound = 1, JoinStyleMiter, JoinStyleBevel } |
| Join styles for buffers. More... | |
| enum | OperationResult { Success = 0, NothingHappened = 1000, InvalidBaseGeometry, InvalidInputGeometryType, SelectionIsEmpty, SelectionIsGreaterThanOne, GeometryEngineError, LayerNotEditable, AddPartSelectedGeometryNotFound, AddPartNotMultiGeometry, AddRingNotClosed, AddRingNotValid, AddRingCrossesExistingRings, AddRingNotInExistingFeature, SplitCannotSplitPoint } |
| Success or failure of a geometry operation. More... | |
| enum | ValidationMethod { ValidatorQgisInternal, ValidatorGeos } |
| Available methods for validating geometries. More... | |
Public Member Functions | |
| QgsGeometry () | |
| Constructor. More... | |
| QgsGeometry (const QgsGeometry &) | |
| Copy constructor will prompt a deep copy of the object. More... | |
| QgsGeometry (QgsAbstractGeometry *geom) | |
| Creates a geometry from an abstract geometry object. More... | |
| QgsGeometry (std::unique_ptr< QgsAbstractGeometry > geom) | |
| Creates a geometry from an abstract geometry object. More... | |
| ~QgsGeometry () | |
| OperationResult | addPart (const QVector< QgsPointXY > &points, QgsWkbTypes::GeometryType geomType=QgsWkbTypes::UnknownGeometry) |
| Adds a new part to a the geometry. More... | |
| OperationResult | addPart (const QgsPointSequence &points, QgsWkbTypes::GeometryType geomType=QgsWkbTypes::UnknownGeometry) |
| Adds a new part to a the geometry. More... | |
| OperationResult | addPart (QgsAbstractGeometry *part, QgsWkbTypes::GeometryType geomType=QgsWkbTypes::UnknownGeometry) |
| Adds a new part to this geometry. More... | |
| OperationResult | addPart (const QgsGeometry &newPart) |
| Adds a new island polygon to a multipolygon feature. More... | |
| OperationResult | addRing (const QVector< QgsPointXY > &ring) |
| Adds a new ring to this geometry. More... | |
| OperationResult | addRing (QgsCurve *ring) |
| Adds a new ring to this geometry. More... | |
| void | adjacentVertices (int atVertex, int &beforeVertex, int &afterVertex) const |
| Returns the indexes of the vertices before and after the given vertex index. More... | |
| double | angleAtVertex (int vertex) const |
| Returns the bisector angle for this geometry at the specified vertex. More... | |
| double | area () const |
| Returns the area of the geometry using GEOS. More... | |
| QVector< QgsGeometry > | asGeometryCollection () const |
| Returns contents of the geometry as a list of geometries. More... | |
| QString | asJson (int precision=17) const |
| Exports the geometry to a GeoJSON string. More... | |
| QgsMultiPointXY | asMultiPoint () const |
| Returns the contents of the geometry as a multi-point. More... | |
| QgsMultiPolygonXY | asMultiPolygon () const |
| Returns the contents of the geometry as a multi-polygon. More... | |
| QgsMultiPolylineXY | asMultiPolyline () const |
| Returns the contents of the geometry as a multi-linestring. More... | |
| QgsPointXY | asPoint () const |
| Returns the contents of the geometry as a 2-dimensional point. More... | |
| QgsPolygonXY | asPolygon () const |
| Returns the contents of the geometry as a polygon. More... | |
| QgsPolylineXY | asPolyline () const |
| Returns the contents of the geometry as a polyline. More... | |
| QPointF | asQPointF () const |
| Returns contents of the geometry as a QPointF if wkbType is WKBPoint, otherwise returns a null QPointF. More... | |
| QPolygonF | asQPolygonF () const |
| Returns contents of the geometry as a QPolygonF. More... | |
| QByteArray | asWkb () const |
| Export the geometry to WKB. More... | |
| QString | asWkt (int precision=17) const |
| Exports the geometry to WKT. More... | |
| int | avoidIntersections (const QList< QgsVectorLayer *> &avoidIntersectionsLayers, const QHash< QgsVectorLayer *, QSet< QgsFeatureId > > &ignoreFeatures=(QHash< QgsVectorLayer *, QSet< QgsFeatureId > >())) |
| Modifies geometry to avoid intersections with the layers specified in project properties. More... | |
| QgsRectangle | boundingBox () const |
| Returns the bounding box of the geometry. More... | |
| bool | boundingBoxIntersects (const QgsRectangle &rectangle) const |
| Returns true if the bounding box of this geometry intersects with a rectangle. More... | |
| bool | boundingBoxIntersects (const QgsGeometry &geometry) const |
| Returns true if the bounding box of this geometry intersects with the bounding box of another geometry. More... | |
| QgsGeometry | buffer (double distance, int segments) const |
| Returns a buffer region around this geometry having the given width and with a specified number of segments used to approximate curves. More... | |
| QgsGeometry | buffer (double distance, int segments, EndCapStyle endCapStyle, JoinStyle joinStyle, double miterLimit) const |
| Returns a buffer region around the geometry, with additional style options. More... | |
| QgsGeometry | centroid () const |
| Returns the center of mass of a geometry. More... | |
| QgsGeometry | clipped (const QgsRectangle &rectangle) |
| Clips the geometry using the specified rectangle. More... | |
| double | closestSegmentWithContext (const QgsPointXY &point, QgsPointXY &minDistPoint, int &afterVertex, int *leftOf=nullptr, double epsilon=DEFAULT_SEGMENT_EPSILON) const |
| Searches for the closest segment of geometry to the given point. More... | |
| QgsPointXY | closestVertex (const QgsPointXY &point, int &atVertex, int &beforeVertex, int &afterVertex, double &sqrDist) const |
| Returns the vertex closest to the given point, the corresponding vertex index, squared distance snap point / target point and the indices of the vertices before and after the closest vertex. More... | |
| double | closestVertexWithContext (const QgsPointXY &point, int &atVertex) const |
| Searches for the closest vertex in this geometry to the given point. More... | |
| QgsGeometry | combine (const QgsGeometry &geometry) const |
| Returns a geometry representing all the points in this geometry and other (a union geometry operation). More... | |
| QgsAbstractGeometry::const_part_iterator | const_parts_begin () const |
| Returns STL-style const iterator pointing to the first part of the geometry. More... | |
| QgsAbstractGeometry::const_part_iterator | const_parts_end () const |
| Returns STL-style iterator pointing to the imaginary part after the last part of the geometry. More... | |
| const QgsAbstractGeometry * | constGet () const |
| Returns a non-modifiable (const) reference to the underlying abstract geometry primitive. More... | |
| QgsGeometryConstPartIterator | constParts () const |
| Returns Java-style iterator for traversal of parts of the geometry. More... | |
| bool | contains (const QgsPointXY *p) const |
| Tests for containment of a point (uses GEOS) More... | |
| bool | contains (const QgsGeometry &geometry) const |
| Tests for if geometry is contained in another (uses GEOS) More... | |
| bool | convertGeometryCollectionToSubclass (QgsWkbTypes::GeometryType geomType) |
| Converts geometry collection to a the desired geometry type subclass (multi-point, multi-linestring or multi-polygon). More... | |
| bool | convertToMultiType () |
| Converts single type geometry into multitype geometry e.g. More... | |
| bool | convertToSingleType () |
| Converts multi type geometry into single type geometry e.g. More... | |
| void | convertToStraightSegment (double tolerance=M_PI/180., QgsAbstractGeometry::SegmentationToleranceType toleranceType=QgsAbstractGeometry::MaximumAngle) |
| Converts the geometry to straight line segments, if it is a curved geometry type. More... | |
| QgsGeometry | convertToType (QgsWkbTypes::GeometryType destType, bool destMultipart=false) const |
| Try to convert the geometry to the requested type. More... | |
| QgsGeometry | convexHull () const |
| Returns the smallest convex polygon that contains all the points in the geometry. More... | |
| bool | crosses (const QgsGeometry &geometry) const |
| Test for if geometry crosses another (uses GEOS) More... | |
| QgsGeometry | delaunayTriangulation (double tolerance=0.0, bool edgesOnly=false) const |
| Returns the Delaunay triangulation for the vertices of the geometry. More... | |
| bool | deletePart (int partNum) |
| Deletes part identified by the part number. More... | |
| bool | deleteRing (int ringNum, int partNum=0) |
| Deletes a ring in polygon or multipolygon. More... | |
| bool | deleteVertex (int atVertex) |
| Deletes the vertex at the given position number and item (first number is index 0) More... | |
| QgsGeometry | densifyByCount (int extraNodesPerSegment) const |
| Returns a copy of the geometry which has been densified by adding the specified number of extra nodes within each segment of the geometry. More... | |
| QgsGeometry | densifyByDistance (double distance) const |
| Densifies the geometry by adding regularly placed extra nodes inside each segment so that the maximum distance between any two nodes does not exceed the specified distance. More... | |
| QgsGeometry | difference (const QgsGeometry &geometry) const |
| Returns a geometry representing the points making up this geometry that do not make up other. More... | |
| bool | disjoint (const QgsGeometry &geometry) const |
| Tests for if geometry is disjoint of another (uses GEOS) More... | |
| double | distance (const QgsGeometry &geom) const |
| Returns the minimum distance between this geometry and another geometry, using GEOS. More... | |
| double | distanceToVertex (int vertex) const |
| Returns the distance along this geometry from its first vertex to the specified vertex. More... | |
| void | draw (QPainter &p) const |
| Draws the geometry onto a QPainter. More... | |
| bool | equals (const QgsGeometry &geometry) const |
| Test if this geometry is exactly equal to another geometry. More... | |
| QgsGeometry | extendLine (double startDistance, double endDistance) const |
| Extends a (multi)line geometry by extrapolating out the start or end of the line by a specified distance. More... | |
| QgsGeometry | extrude (double x, double y) |
| Returns an extruded version of this geometry. More... | |
| 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. More... | |
| QgsGeometry | forceRHR () const |
| Forces geometries to respect the Right-Hand-Rule, in which the area that is bounded by a polygon is to the right of the boundary. More... | |
| void | fromWkb (unsigned char *wkb, int length) |
| Set the geometry, feeding in the buffer containing OGC Well-Known Binary and the buffer's length. More... | |
| void | fromWkb (const QByteArray &wkb) |
| Set the geometry, feeding in the buffer containing OGC Well-Known Binary. More... | |
| QgsAbstractGeometry * | get () |
| Returns a modifiable (non-const) reference to the underlying abstract geometry primitive. More... | |
| double | hausdorffDistance (const QgsGeometry &geom) const |
| Returns the Hausdorff distance between this geometry and geom. More... | |
| double | hausdorffDistanceDensify (const QgsGeometry &geom, double densifyFraction) const |
| Returns the Hausdorff distance between this geometry and geom. More... | |
| bool | insertVertex (double x, double y, int beforeVertex) |
| Insert a new vertex before the given vertex index, ring and item (first number is index 0) If the requested vertex number (beforeVertex.back()) is greater than the last actual vertex on the requested ring and item, it is assumed that the vertex is to be appended instead of inserted. More... | |
| bool | insertVertex (const QgsPoint &point, int beforeVertex) |
| Insert a new vertex before the given vertex index, ring and item (first number is index 0) If the requested vertex number (beforeVertex.back()) is greater than the last actual vertex on the requested ring and item, it is assumed that the vertex is to be appended instead of inserted. More... | |
| QgsGeometry | interpolate (double distance) const |
| Returns an interpolated point on the geometry at the specified distance. More... | |
| double | interpolateAngle (double distance) const |
| Returns the angle parallel to the linestring or polygon boundary at the specified distance along the geometry. More... | |
| QgsGeometry | intersection (const QgsGeometry &geometry) const |
| Returns a geometry representing the points shared by this geometry and other. More... | |
| bool | intersects (const QgsRectangle &rectangle) const |
| Returns true if this geometry exactly intersects with a rectangle. More... | |
| bool | intersects (const QgsGeometry &geometry) const |
| Returns true if this geometry exactly intersects with another geometry. More... | |
| bool | isEmpty () const |
| Returns true if the geometry is empty (eg a linestring with no vertices, or a collection with no geometries). More... | |
| bool | isGeosEqual (const QgsGeometry &) const |
| Compares the geometry with another geometry using GEOS. More... | |
| bool | isGeosValid () const |
| Checks validity of the geometry using GEOS. More... | |
| bool | isMultipart () const |
| Returns true if WKB of the geometry is of WKBMulti* type. More... | |
| bool | isNull () const |
| Returns true if the geometry is null (ie, contains no underlying geometry accessible via geometry() ). More... | |
| bool | isSimple () const |
| Determines whether the geometry is simple (according to OGC definition), i.e. More... | |
| QString | lastError () const |
| Returns an error string referring to the last error encountered either when this geometry was created or when an operation was performed on the geometry. More... | |
| double | length () const |
| Returns the length of geometry using GEOS. More... | |
| double | lineLocatePoint (const QgsGeometry &point) const |
| Returns a distance representing the location along this linestring of the closest point on this linestring geometry to the specified point. More... | |
| QgsGeometry | makeDifference (const QgsGeometry &other) const |
| Returns the geometry formed by modifying this geometry such that it does not intersect the other geometry. More... | |
| int | makeDifferenceInPlace (const QgsGeometry &other) |
| Changes this geometry such that it does not intersect the other geometry. More... | |
| QgsGeometry | makeValid () const |
| Attempts to make an invalid geometry valid without losing vertices. More... | |
| void | mapToPixel (const QgsMapToPixel &mtp) |
| Transforms the geometry from map units to pixels in place. More... | |
| QgsGeometry | mergeLines () const |
| Merges any connected lines in a LineString/MultiLineString geometry and converts them to single line strings. More... | |
| QgsGeometry | minimalEnclosingCircle (QgsPointXY ¢er, double &radius, unsigned int segments=36) const |
| Returns the minimal enclosing circle for the geometry. More... | |
| QgsGeometry | minimalEnclosingCircle (unsigned int segments=36) const |
| Returns the minimal enclosing circle for the geometry. More... | |
| bool | moveVertex (double x, double y, int atVertex) |
| Moves the vertex at the given position number and item (first number is index 0) to the given coordinates. More... | |
| bool | moveVertex (const QgsPoint &p, int atVertex) |
| Moves the vertex at the given position number and item (first number is index 0) to the given coordinates. More... | |
| QgsGeometry | nearestPoint (const QgsGeometry &other) const |
| Returns the nearest point on this geometry to another geometry. More... | |
| QgsGeometry | offsetCurve (double distance, int segments, JoinStyle joinStyle, double miterLimit) const |
| Returns an offset line at a given distance and side from an input line. More... | |
| operator QVariant () const | |
| Allows direct construction of QVariants from geometry. More... | |
| QgsGeometry & | operator= (QgsGeometry const &rhs) |
| Creates a deep copy of the object. More... | |
| QgsGeometry | orientedMinimumBoundingBox (double &area, double &angle, double &width, double &height) const |
| Returns the oriented minimum bounding box for the geometry, which is the smallest (by area) rotated rectangle which fully encompasses the geometry. More... | |
| QgsGeometry | orientedMinimumBoundingBox () const |
| Returns the oriented minimum bounding box for the geometry, which is the smallest (by area) rotated rectangle which fully encompasses the geometry. More... | |
| QgsGeometry | orthogonalize (double tolerance=1.0E-8, int maxIterations=1000, double angleThreshold=15.0) const |
| Attempts to orthogonalize a line or polygon geometry by shifting vertices to make the geometries angles either right angles or flat lines. More... | |
| bool | overlaps (const QgsGeometry &geometry) const |
| Test for if geometry overlaps another (uses GEOS) More... | |
| QgsGeometryPartIterator | parts () |
| Returns Java-style iterator for traversal of parts of the geometry. More... | |
| QgsAbstractGeometry::part_iterator | parts_begin () |
| Returns STL-style iterator pointing to the first part of the geometry. More... | |
| QgsAbstractGeometry::part_iterator | parts_end () |
| Returns STL-style iterator pointing to the imaginary part after the last part of the geometry. More... | |
| QgsGeometry | pointOnSurface () const |
| Returns a point guaranteed to lie on the surface of a geometry. More... | |
| QgsGeometry | poleOfInaccessibility (double precision, double *distanceToBoundary=nullptr) const |
| Calculates the approximate pole of inaccessibility for a surface, which is the most distant internal point from the boundary of the surface. More... | |
| bool | removeDuplicateNodes (double epsilon=4 *std::numeric_limits< double >::epsilon(), bool useZValues=false) |
| Removes duplicate nodes from the geometry, wherever removing the nodes does not result in a degenerate geometry. More... | |
| QgsGeometry | removeInteriorRings (double minimumAllowedArea=-1) const |
| Removes the interior rings from a (multi)polygon geometry. More... | |
| bool | requiresConversionToStraightSegments () const |
| Returns true if the geometry is a curved geometry type which requires conversion to display as straight line segments. More... | |
| OperationResult | reshapeGeometry (const QgsLineString &reshapeLineString) |
| Replaces a part of this geometry with another line. More... | |
| OperationResult | rotate (double rotation, const QgsPointXY ¢er) |
| Rotate this geometry around the Z axis. More... | |
| void | set (QgsAbstractGeometry *geometry) |
| Sets the underlying geometry store. More... | |
| QgsGeometry | shortestLine (const QgsGeometry &other) const |
| Returns the shortest line joining this geometry to another geometry. More... | |
| QgsGeometry | simplify (double tolerance) const |
| Returns a simplified version of this geometry using a specified tolerance value. More... | |
| QgsGeometry | singleSidedBuffer (double distance, int segments, BufferSide side, JoinStyle joinStyle=JoinStyleRound, double miterLimit=2.0) const |
| Returns a single sided buffer for a (multi)line geometry. More... | |
| QgsGeometry | smooth (unsigned int iterations=1, double offset=0.25, double minimumDistance=-1.0, double maxAngle=180.0) const |
| Smooths a geometry by rounding off corners using the Chaikin algorithm. More... | |
| QgsGeometry | snappedToGrid (double hSpacing, double vSpacing, double dSpacing=0, double mSpacing=0) const |
| Returns a new geometry with all points or vertices snapped to the closest point of the grid. More... | |
| OperationResult | splitGeometry (const QVector< QgsPointXY > &splitLine, QVector< QgsGeometry > &newGeometries, bool topological, QVector< QgsPointXY > &topologyTestPoints) |
| Splits this geometry according to a given line. More... | |
| double | sqrDistToVertexAt (QgsPointXY &point SIP_IN, int atVertex) const |
| Returns the squared Cartesian distance between the given point to the given vertex index (vertex at the given position number, ring and item (first number is index 0)) More... | |
| QgsGeometry | subdivide (int maxNodes=256) const |
| Subdivides the geometry. More... | |
| QgsGeometry | symDifference (const QgsGeometry &geometry) const |
| Returns a geometry representing the points making up this geometry that do not make up other. More... | |
| QgsGeometry | taperedBuffer (double startWidth, double endWidth, int segments) const |
| Calculates a variable width buffer ("tapered buffer") for a (multi)curve geometry. More... | |
| bool | touches (const QgsGeometry &geometry) const |
| Test for if geometry touch another (uses GEOS) More... | |
| OperationResult | transform (const QgsCoordinateTransform &ct, QgsCoordinateTransform::TransformDirection direction=QgsCoordinateTransform::ForwardTransform, bool transformZ=false) SIP_THROW(QgsCsException) |
| Transforms this geometry as described by the coordinate transform ct. More... | |
| OperationResult | transform (const QTransform &t, double zTranslate=0.0, double zScale=1.0, double mTranslate=0.0, double mScale=1.0) |
| Transforms the x and y components of the geometry using a QTransform object t. More... | |
| void | transformVertices (const std::function< QgsPoint(const QgsPoint &) > &transform) |
| Transforms the vertices from the geometry in place, applying the transform function to every vertex. More... | |
| OperationResult | translate (double dx, double dy, double dz=0.0, double dm=0.0) |
| Translates this geometry by dx, dy, dz and dm. More... | |
| QgsWkbTypes::GeometryType | type () const |
| Returns type of the geometry as a QgsWkbTypes::GeometryType. More... | |
| void | validateGeometry (QVector< QgsGeometry::Error > &errors, ValidationMethod method=ValidatorQgisInternal) const |
| Validates geometry and produces a list of geometry errors. More... | |
| QgsGeometry | variableWidthBufferByM (int segments) const |
| Calculates a variable width buffer for a (multi)linestring geometry, where the width at each node is taken from the linestring m values. More... | |
| QgsPoint | vertexAt (int atVertex) const |
| Returns coordinates of a vertex. More... | |
| bool | vertexIdFromVertexNr (int number, QgsVertexId &id) const |
| Calculates the vertex ID from a vertex number. More... | |
| int | vertexNrFromVertexId (QgsVertexId id) const |
| Returns the vertex number corresponding to a vertex id. More... | |
| QgsVertexIterator | vertices () const |
| Returns a read-only, Java-style iterator for traversal of vertices of all the geometry, including all geometry parts and rings. More... | |
| QgsAbstractGeometry::vertex_iterator | vertices_begin () const |
| Returns STL-style iterator pointing to the first vertex of the geometry. More... | |
| QgsAbstractGeometry::vertex_iterator | vertices_end () const |
| Returns STL-style iterator pointing to the imaginary vertex after the last vertex of the geometry. More... | |
| QgsGeometry | voronoiDiagram (const QgsGeometry &extent=QgsGeometry(), double tolerance=0.0, bool edgesOnly=false) const |
| Creates a Voronoi diagram for the nodes contained within the geometry. More... | |
| bool | within (const QgsGeometry &geometry) const |
| Test for if geometry is within another (uses GEOS) More... | |
| QgsWkbTypes::Type | wkbType () const |
| Returns type of the geometry as a WKB type (point / linestring / polygon etc.) More... | |
Static Public Member Functions | |
| static QgsGeometry | collectGeometry (const QVector< QgsGeometry > &geometries) |
| Creates a new multipart geometry from a list of QgsGeometry objects. More... | |
| static bool | compare (const QgsPolylineXY &p1, const QgsPolylineXY &p2, double epsilon=4 *std::numeric_limits< double >::epsilon()) |
| Compares two polylines for equality within a specified tolerance. More... | |
| static bool | compare (const QgsPolygonXY &p1, const QgsPolygonXY &p2, double epsilon=4 *std::numeric_limits< double >::epsilon()) |
| Compares two polygons for equality within a specified tolerance. More... | |
| static bool | compare (const QgsMultiPolygonXY &p1, const QgsMultiPolygonXY &p2, double epsilon=4 *std::numeric_limits< double >::epsilon()) |
| Compares two multipolygons for equality within a specified tolerance. More... | |
| static void | convertPointList (const QVector< QgsPointXY > &input, QgsPointSequence &output) |
| Upgrades a point list from QgsPointXY to QgsPoint. More... | |
| static void | convertPointList (const QgsPointSequence &input, QVector< QgsPointXY > &output) |
| Downgrades a point list from QgsPoint to QgsPointXY. More... | |
| static QgsGeometryEngine * | createGeometryEngine (const QgsAbstractGeometry *geometry) |
| Creates and returns a new geometry engine. More... | |
| static QgsPolygonXY | createPolygonFromQPolygonF (const QPolygonF &polygon) |
| Creates a QgsPolygonXYfrom a QPolygonF. More... | |
| static QgsPolylineXY | createPolylineFromQPolygonF (const QPolygonF &polygon) |
| Creates a QgsPolylineXY from a QPolygonF. More... | |
| static QgsGeometry | createWedgeBuffer (const QgsPoint ¢er, double azimuth, double angularWidth, double outerRadius, double innerRadius=0) |
| Creates a wedge shaped buffer from a center point. More... | |
| static QgsGeometry | fromMultiPointXY (const QgsMultiPointXY &multipoint) |
| Creates a new geometry from a QgsMultiPointXY object. More... | |
| static QgsGeometry | fromMultiPolygonXY (const QgsMultiPolygonXY &multipoly) |
| Creates a new geometry from a QgsMultiPolygon. More... | |
| static QgsGeometry | fromMultiPolylineXY (const QgsMultiPolylineXY &multiline) |
| Creates a new geometry from a QgsMultiPolylineXY object. More... | |
| static QgsGeometry | fromPointXY (const QgsPointXY &point) |
| Creates a new geometry from a QgsPointXY object. More... | |
| static QgsGeometry | fromPolygonXY (const QgsPolygonXY &polygon) |
| Creates a new geometry from a QgsPolygon. More... | |
| static QgsGeometry | fromPolyline (const QgsPolyline &polyline) |
| Creates a new LineString geometry from a list of QgsPoint points. More... | |
| static QgsGeometry | fromPolylineXY (const QgsPolylineXY &polyline) |
| Creates a new LineString geometry from a list of QgsPointXY points. More... | |
| static QgsGeometry | fromQPointF (QPointF point) |
| Construct geometry from a QPointF. More... | |
| static QgsGeometry | fromQPolygonF (const QPolygonF &polygon) |
| Construct geometry from a QPolygonF. More... | |
| static QgsGeometry | fromRect (const QgsRectangle &rect) |
| Creates a new geometry from a QgsRectangle. More... | |
| static QgsGeometry | fromWkt (const QString &wkt) |
| Creates a new geometry from a WKT string. More... | |
| static QgsGeometry | polygonize (const QVector< QgsGeometry > &geometries) |
| Creates a GeometryCollection geometry containing possible polygons formed from the constituent linework of a set of geometries. More... | |
| static QgsGeometry | unaryUnion (const QVector< QgsGeometry > &geometries) |
| Compute the unary union on a list of geometries. More... | |
Properties | |
| bool | isNull |
| QgsWkbTypes::GeometryType | type |
Friends | |
| class | QgsInternalGeometryEngine |
A geometry is the spatial representation of a feature.
Since QGIS 2.10, QgsGeometry acts as a generic container for geometry objects. QgsGeometry is implicitly shared, so making copies of geometries is inexpensive. The geometry container class can also be stored inside a QVariant object.
The actual geometry representation is stored as a QgsAbstractGeometry within the container, and can be accessed via the get() method or set using the set() method.
Definition at line 106 of file qgsgeometry.h.
Side of line to buffer.
| Enumerator | |
|---|---|
| SideLeft | Buffer to left of line. |
| SideRight | Buffer to right of line. |
Definition at line 1028 of file qgsgeometry.h.
End cap styles for buffers.
| Enumerator | |
|---|---|
| CapRound | Round cap. |
| CapFlat | Flat cap (in line with start/end of line) |
| CapSquare | Square cap (extends past start/end of line by buffer distance) |
Definition at line 1036 of file qgsgeometry.h.
Join styles for buffers.
| Enumerator | |
|---|---|
| JoinStyleRound | Use rounded joins. |
| JoinStyleMiter | Use mitered joins. |
| JoinStyleBevel | Use beveled joins. |
Definition at line 1045 of file qgsgeometry.h.
Success or failure of a geometry operation.
This gives details about cause of failure.
Definition at line 118 of file qgsgeometry.h.
Available methods for validating geometries.
| Enumerator | |
|---|---|
| ValidatorQgisInternal | Use internal QgsGeometryValidator method. |
| ValidatorGeos | Use GEOS validation methods. |
Definition at line 1854 of file qgsgeometry.h.
| QgsGeometry::QgsGeometry | ( | ) |
Constructor.
Definition at line 57 of file qgsgeometry.cpp.
| QgsGeometry::QgsGeometry | ( | const QgsGeometry & | other | ) |
Copy constructor will prompt a deep copy of the object.
Definition at line 82 of file qgsgeometry.cpp.
|
explicit |
Creates a geometry from an abstract geometry object.
Ownership of geom is transferred.
Definition at line 68 of file qgsgeometry.cpp.
|
explicit |
Creates a geometry from an abstract geometry object.
Ownership of geom is transferred.
Definition at line 75 of file qgsgeometry.cpp.
| QgsGeometry::~QgsGeometry | ( | ) |
Definition at line 62 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::addPart | ( | const QVector< QgsPointXY > & | points, |
| QgsWkbTypes::GeometryType | geomType = QgsWkbTypes::UnknownGeometry |
||
| ) |
Adds a new part to a the geometry.
| points | points describing part to add |
| geomType | default geometry type to create if no existing geometry |
Definition at line 673 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::addPart | ( | const QgsPointSequence & | points, |
| QgsWkbTypes::GeometryType | geomType = QgsWkbTypes::UnknownGeometry |
||
| ) |
Adds a new part to a the geometry.
| points | points describing part to add |
| geomType | default geometry type to create if no existing geometry |
Definition at line 680 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::addPart | ( | QgsAbstractGeometry * | part, |
| QgsWkbTypes::GeometryType | geomType = QgsWkbTypes::UnknownGeometry |
||
| ) |
Adds a new part to this geometry.
| part | part to add (ownership is transferred) |
| geomType | default geometry type to create if no existing geometry |
Definition at line 696 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::addPart | ( | const QgsGeometry & | newPart | ) |
Adds a new island polygon to a multipolygon feature.
Definition at line 726 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::addRing | ( | const QVector< QgsPointXY > & | ring | ) |
Adds a new ring to this geometry.
This makes only sense for polygon and multipolygons.
| ring | The ring to be added |
Definition at line 654 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::addRing | ( | QgsCurve * | ring | ) |
Adds a new ring to this geometry.
This makes only sense for polygon and multipolygons.
| ring | The ring to be added |
Definition at line 660 of file qgsgeometry.cpp.
| void QgsGeometry::adjacentVertices | ( | int | atVertex, |
| int & | beforeVertex, | ||
| int & | afterVertex | ||
| ) | const |
Returns the indexes of the vertices before and after the given vertex index.
This function takes into account the following factors:
Definition at line 432 of file qgsgeometry.cpp.
| double QgsGeometry::angleAtVertex | ( | int | vertex | ) | const |
Returns the bisector angle for this geometry at the specified vertex.
| vertex | vertex index to calculate bisector angle at |
Definition at line 416 of file qgsgeometry.cpp.
| double QgsGeometry::area | ( | ) | const |
Returns the area of the geometry using GEOS.
Definition at line 1582 of file qgsgeometry.cpp.
| QVector< QgsGeometry > QgsGeometry::asGeometryCollection | ( | ) | const |
Returns contents of the geometry as a list of geometries.
Definition at line 2298 of file qgsgeometry.cpp.
| QString QgsGeometry::asJson | ( | int | precision = 17 | ) | const |
Exports the geometry to a GeoJSON string.
Definition at line 1262 of file qgsgeometry.cpp.
| QgsMultiPointXY QgsGeometry::asMultiPoint | ( | ) | const |
Returns the contents of the geometry as a multi-point.
Any z or m values present in the geometry will be discarded.
Definition at line 1471 of file qgsgeometry.cpp.
| QgsMultiPolygonXY QgsGeometry::asMultiPolygon | ( | ) | const |
Returns the contents of the geometry as a multi-polygon.
Any z or m values present in the geometry will be discarded. If the geometry is a curved polygon type (such as a MultiSurface), it will be automatically segmentized.
Definition at line 1539 of file qgsgeometry.cpp.
| QgsMultiPolylineXY QgsGeometry::asMultiPolyline | ( | ) | const |
Returns the contents of the geometry as a multi-linestring.
Any z or m values present in the geometry will be discarded. If the geometry is a curved line type (such as a MultiCurve), it will be automatically segmentized.
Definition at line 1495 of file qgsgeometry.cpp.
| QgsPointXY QgsGeometry::asPoint | ( | ) | const |
Returns the contents of the geometry as a 2-dimensional point.
Any z or m values present in the geometry will be discarded.
Definition at line 1379 of file qgsgeometry.cpp.
| QgsPolygonXY QgsGeometry::asPolygon | ( | ) | const |
Returns the contents of the geometry as a polygon.
Any z or m values present in the geometry will be discarded. If the geometry is a curved polygon type (such as a CurvePolygon), it will be automatically segmentized.
Definition at line 1436 of file qgsgeometry.cpp.
| QgsPolylineXY QgsGeometry::asPolyline | ( | ) | const |
Returns the contents of the geometry as a polyline.
Any z or m values present in the geometry will be discarded. If the geometry is a curved line type (such as a CircularString), it will be automatically segmentized.
Definition at line 1394 of file qgsgeometry.cpp.
| QPointF QgsGeometry::asQPointF | ( | ) | const |
Returns contents of the geometry as a QPointF if wkbType is WKBPoint, otherwise returns a null QPointF.
Definition at line 2324 of file qgsgeometry.cpp.
| QPolygonF QgsGeometry::asQPolygonF | ( | ) | const |
Returns contents of the geometry as a QPolygonF.
If geometry is a linestring, then the result will be an open QPolygonF. If the geometry is a polygon, then the result will be a closed QPolygonF of the geometry's exterior ring.
Definition at line 2330 of file qgsgeometry.cpp.
| QByteArray QgsGeometry::asWkb | ( | ) | const |
| QString QgsGeometry::asWkt | ( | int | precision = 17 | ) | const |
Exports the geometry to WKT.
Definition at line 1253 of file qgsgeometry.cpp.
| int QgsGeometry::avoidIntersections | ( | const QList< QgsVectorLayer *> & | avoidIntersectionsLayers, |
| const QHash< QgsVectorLayer *, QSet< QgsFeatureId > > & | ignoreFeatures = ( QHash<QgsVectorLayer *, QSet<QgsFeatureId> >() ) |
||
| ) |
Modifies geometry to avoid intersections with the layers specified in project properties.
| avoidIntersectionsLayers | list of layers to check for intersections |
| ignoreFeatures | possibility to give a list of features where intersections should be ignored (not available in Python bindings) |
Definition at line 2389 of file qgsgeometry.cpp.
| QgsRectangle QgsGeometry::boundingBox | ( | ) | const |
Returns the bounding box of the geometry.
Definition at line 933 of file qgsgeometry.cpp.
| bool QgsGeometry::boundingBoxIntersects | ( | const QgsRectangle & | rectangle | ) | const |
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.
Definition at line 1133 of file qgsgeometry.cpp.
| bool QgsGeometry::boundingBoxIntersects | ( | const QgsGeometry & | geometry | ) | const |
Returns true if the bounding box of this geometry intersects with the bounding box of another geometry.
Since this test only considers the bounding box of the geometries, is is very fast to calculate and handles invalid geometries.
Definition at line 1143 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::buffer | ( | double | distance, |
| int | segments | ||
| ) | const |
Returns a buffer region around this geometry having the given width and with a specified number of segments used to approximate curves.
Definition at line 1726 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::buffer | ( | double | distance, |
| int | segments, | ||
| EndCapStyle | endCapStyle, | ||
| JoinStyle | joinStyle, | ||
| double | miterLimit | ||
| ) | const |
Returns a buffer region around the geometry, with additional style options.
| distance | buffer distance |
| segments | for round joins, number of segments to approximate quarter-circle |
| endCapStyle | end cap style |
| joinStyle | join style for corners in geometry |
| miterLimit | limit on the miter ratio used for very sharp corners (JoinStyleMiter only) |
Definition at line 1745 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::centroid | ( | ) | const |
Returns the center of mass of a geometry.
If the input is a NULL geometry, the output will also be a NULL geometry.
If an error was encountered while creating the result, more information can be retrieved by calling error() on the returned geometry.
Definition at line 1953 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::clipped | ( | const QgsRectangle & | rectangle | ) |
Clips the geometry using the specified rectangle.
Performs a fast, non-robust intersection between the geometry and a rectangle. The returned geometry may be invalid.
Definition at line 2589 of file qgsgeometry.cpp.
| double QgsGeometry::closestSegmentWithContext | ( | const QgsPointXY & | point, |
| QgsPointXY & | minDistPoint, | ||
| int & | afterVertex, | ||
| int * | leftOf = nullptr, |
||
| double | epsilon = DEFAULT_SEGMENT_EPSILON |
||
| ) | const |
Searches for the closest segment of geometry to the given point.
| point | Specifies the point for search |
| minDistPoint | Receives the nearest point on the segment |
| afterVertex | Receives index of the vertex after the closest segment. The vertex before the closest segment is always afterVertex - 1 |
| leftOf | Out: Returns if the point lies on the left of left side of the geometry ( < 0 means left, > 0 means right, 0 indicates that the test was unsuccessful, e.g. for a point exactly on the line) |
| epsilon | epsilon for segment snapping |
Definition at line 630 of file qgsgeometry.cpp.
| QgsPointXY QgsGeometry::closestVertex | ( | const QgsPointXY & | point, |
| int & | atVertex, | ||
| int & | beforeVertex, | ||
| int & | afterVertex, | ||
| double & | sqrDist | ||
| ) | const |
Returns the vertex closest to the given point, the corresponding vertex index, squared distance snap point / target point and the indices of the vertices before and after the closest vertex.
| point | point to search for |
| atVertex | will be set to the vertex index of the closest found vertex |
| beforeVertex | will be set to the vertex index of the previous vertex from the closest one. Will be set to -1 if not present. |
| afterVertex | will be set to the vertex index of the next vertex after the closest one. Will be set to -1 if not present. |
| sqrDist | will be set to the square distance between the closest vertex and the specified point |
Definition at line 372 of file qgsgeometry.cpp.
| double QgsGeometry::closestVertexWithContext | ( | const QgsPointXY & | point, |
| int & | atVertex | ||
| ) | const |
Searches for the closest vertex in this geometry to the given point.
| point | Specifiest the point for search |
| atVertex | Receives index of the closest vertex |
Definition at line 614 of file qgsgeometry.cpp.
|
static |
Creates a new multipart geometry from a list of QgsGeometry objects.
Definition at line 243 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::combine | ( | const QgsGeometry & | geometry | ) | const |
Returns a geometry representing all the points in this geometry and other (a union geometry operation).
If the input is a NULL geometry, the output will also be a NULL geometry.
If an error was encountered while creating the result, more information can be retrieved by calling error() on the returned geometry.
Definition at line 2207 of file qgsgeometry.cpp.
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static |
Compares two polylines for equality within a specified tolerance.
| p1 | first polyline |
| p2 | second polyline |
| epsilon | maximum difference for coordinates between the polylines |
Definition at line 2845 of file qgsgeometry.cpp.
|
static |
Compares two polygons for equality within a specified tolerance.
| p1 | first polygon |
| p2 | second polygon |
| epsilon | maximum difference for coordinates between the polygons |
Definition at line 2858 of file qgsgeometry.cpp.
|
static |
Compares two multipolygons for equality within a specified tolerance.
| p1 | first multipolygon |
| p2 | second multipolygon |
| epsilon | maximum difference for coordinates between the multipolygons |
Definition at line 2872 of file qgsgeometry.cpp.
| QgsAbstractGeometry::const_part_iterator QgsGeometry::const_parts_begin | ( | ) | const |
Returns STL-style const iterator pointing to the first part of the geometry.
This method avoids a detach and is more efficient then parts_begin() for read only iteration.
Definition at line 1695 of file qgsgeometry.cpp.
| QgsAbstractGeometry::const_part_iterator QgsGeometry::const_parts_end | ( | ) | const |
Returns STL-style iterator pointing to the imaginary part after the last part of the geometry.
This method avoids a detach and is more efficient then parts_end() for read only iteration.
Definition at line 1702 of file qgsgeometry.cpp.
| const QgsAbstractGeometry * QgsGeometry::constGet | ( | ) | const |
Returns a non-modifiable (const) reference to the underlying abstract geometry primitive.
This is much faster then calling the non-const get() method.
Definition at line 124 of file qgsgeometry.cpp.
| QgsGeometryConstPartIterator QgsGeometry::constParts | ( | ) | const |
Returns Java-style iterator for traversal of parts of the geometry.
This iterator returns read-only references to parts and cannot be used to modify the parts.
Unlike parts(), this method does not force a detach and is more efficient if read-only iteration only is required.
Definition at line 1718 of file qgsgeometry.cpp.
| bool QgsGeometry::contains | ( | const QgsPointXY * | p | ) | const |
Tests for containment of a point (uses GEOS)
Definition at line 1153 of file qgsgeometry.cpp.
| bool QgsGeometry::contains | ( | const QgsGeometry & | geometry | ) | const |
Tests for if geometry is contained in another (uses GEOS)
Definition at line 1166 of file qgsgeometry.cpp.
| bool QgsGeometry::convertGeometryCollectionToSubclass | ( | QgsWkbTypes::GeometryType | geomType | ) |
Converts geometry collection to a the desired geometry type subclass (multi-point, multi-linestring or multi-polygon).
Child geometries of different type are filtered out. Does nothing the geometry is not a geometry collection. May leave the geometry empty if none of the child geometries match the desired type.
Definition at line 1343 of file qgsgeometry.cpp.
|
static |
Upgrades a point list from QgsPointXY to QgsPoint.
| input | list of QgsPointXY objects to be upgraded |
| output | destination for list of points converted to QgsPoint |
Definition at line 2763 of file qgsgeometry.cpp.
|
static |
Downgrades a point list from QgsPoint to QgsPointXY.
| input | list of QgsPoint objects to be downgraded |
| output | destination for list of points converted to QgsPointXY |
Definition at line 2772 of file qgsgeometry.cpp.
| bool QgsGeometry::convertToMultiType | ( | ) |
Converts single type geometry into multitype geometry e.g.
a polygon into a multipolygon geometry with one polygon If it is already a multipart geometry, it will return true and not change the geometry.
Definition at line 1289 of file qgsgeometry.cpp.
| bool QgsGeometry::convertToSingleType | ( | ) |
Converts multi type geometry into single type geometry e.g.
a multipolygon into a polygon geometry. Only the first part of the multi geometry will be retained. If it is already a single part geometry, it will return true and not change the geometry.
Definition at line 1321 of file qgsgeometry.cpp.
| void QgsGeometry::convertToStraightSegment | ( | double | tolerance = M_PI / 180., |
| QgsAbstractGeometry::SegmentationToleranceType | toleranceType = QgsAbstractGeometry::MaximumAngle |
||
| ) |
Converts the geometry to straight line segments, if it is a curved geometry type.
| tolerance | segmentation tolerance |
| toleranceType | maximum segmentation angle or maximum difference between approximation and curve |
Definition at line 2535 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::convertToType | ( | QgsWkbTypes::GeometryType | destType, |
| bool | destMultipart = false |
||
| ) | const |
Try to convert the geometry to the requested type.
| destType | the geometry type to be converted to |
| destMultipart | determines if the output geometry will be multipart or not |
Definition at line 1271 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::convexHull | ( | ) | const |
Returns the smallest convex polygon that contains all the points in the geometry.
If the input is a NULL geometry, the output will also be a NULL geometry.
If an error was encountered while creating the result, more information can be retrieved by calling error() on the returned geometry.
Definition at line 1999 of file qgsgeometry.cpp.
|
static |
Creates and returns a new geometry engine.
Definition at line 3371 of file qgsgeometry.cpp.
|
static |
Creates a QgsPolygonXYfrom a QPolygonF.
| polygon | source polygon |
Definition at line 2827 of file qgsgeometry.cpp.
|
static |
Creates a QgsPolylineXY from a QPolygonF.
| polygon | source polygon |
Definition at line 2834 of file qgsgeometry.cpp.
|
static |
Creates a wedge shaped buffer from a center point.
The azimuth gives the angle (in degrees) for the middle of the wedge to point. The buffer width (in degrees) is specified by the angularWidth parameter. Note that the wedge will extend to half of the angularWidth either side of the azimuth direction.
The outer radius of the buffer is specified via outerRadius, and optionally an innerRadius can also be specified.
The returned geometry will be a CurvePolygon geometry containing circular strings. It may need to be segmentized to convert to a standard Polygon geometry.
Definition at line 262 of file qgsgeometry.cpp.
| bool QgsGeometry::crosses | ( | const QgsGeometry & | geometry | ) | const |
Test for if geometry crosses another (uses GEOS)
Definition at line 1241 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::delaunayTriangulation | ( | double | tolerance = 0.0, |
| bool | edgesOnly = false |
||
| ) | const |
Returns the Delaunay triangulation for the vertices of the geometry.
The tolerance parameter specifies an optional snapping tolerance which can be used to improve the robustness of the triangulation. If edgesOnly is true than line string boundary geometries will be returned instead of polygons. An empty geometry will be returned if the diagram could not be calculated.
Definition at line 2031 of file qgsgeometry.cpp.
| bool QgsGeometry::deletePart | ( | int | partNum | ) |
Deletes part identified by the part number.
Definition at line 2371 of file qgsgeometry.cpp.
| bool QgsGeometry::deleteRing | ( | int | ringNum, |
| int | partNum = 0 |
||
| ) |
Deletes a ring in polygon or multipolygon.
Ring 0 is outer ring and can't be deleted.
Definition at line 2359 of file qgsgeometry.cpp.
| bool QgsGeometry::deleteVertex | ( | int | atVertex | ) |
Deletes the vertex at the given position number and item (first number is index 0)
Definition at line 489 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::densifyByCount | ( | int | extraNodesPerSegment | ) | const |
Returns a copy of the geometry which has been densified by adding the specified number of extra nodes within each segment of the geometry.
If the geometry has z or m values present then these will be linearly interpolated at the added nodes. Curved geometry types are automatically segmentized by this routine.
Definition at line 1939 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::densifyByDistance | ( | double | distance | ) | const |
Densifies the geometry by adding regularly placed extra nodes inside each segment so that the maximum distance between any two nodes does not exceed the specified distance.
E.g. specifying a distance 3 would cause the segment [0 0] -> [10 0] to be converted to [0 0] -> [2.5 0] -> [5 0] -> [7.5 0] -> [10 0], since 3 extra nodes are required on the segment and spacing these at 2.5 increments allows them to be evenly spaced over the segment. If the geometry has z or m values present then these will be linearly interpolated at the added nodes. Curved geometry types are automatically segmentized by this routine.
Definition at line 1946 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::difference | ( | const QgsGeometry & | geometry | ) | const |
Returns a geometry representing the points making up this geometry that do not make up other.
If the input is a NULL geometry, the output will also be a NULL geometry.
If an error was encountered while creating the result, more information can be retrieved by calling error() on the returned geometry.
Definition at line 2246 of file qgsgeometry.cpp.
| bool QgsGeometry::disjoint | ( | const QgsGeometry & | geometry | ) | const |
Tests for if geometry is disjoint of another (uses GEOS)
Definition at line 1178 of file qgsgeometry.cpp.
| double QgsGeometry::distance | ( | const QgsGeometry & | geom | ) | const |
Returns the minimum distance between this geometry and another geometry, using GEOS.
Will return a negative value if a geometry is missing.
| geom | geometry to find minimum distance to |
Definition at line 1616 of file qgsgeometry.cpp.
| double QgsGeometry::distanceToVertex | ( | int | vertex | ) | const |
Returns the distance along this geometry from its first vertex to the specified vertex.
| vertex | vertex index to calculate distance to |
Definition at line 400 of file qgsgeometry.cpp.
| void QgsGeometry::draw | ( | QPainter & | p | ) | const |
Draws the geometry onto a QPainter.
| p | destination QPainter |
Definition at line 2608 of file qgsgeometry.cpp.
| bool QgsGeometry::equals | ( | const QgsGeometry & | geometry | ) | const |
Test if this geometry is exactly equal to another geometry.
This is a strict equality check, where the underlying geometries must have exactly the same type, component vertices and vertex order.
Calling this method is dramatically faster than the topological equality test performed by isGeosEqual().
Definition at line 1190 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::extendLine | ( | double | startDistance, |
| double | endDistance | ||
| ) | const |
Extends a (multi)line geometry by extrapolating out the start or end of the line by a specified distance.
Lines are extended using the bearing of the first or last segment in the line.
Definition at line 1880 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::extrude | ( | double | x, |
| double | y | ||
| ) |
Returns an extruded version of this geometry.
Definition at line 2286 of file qgsgeometry.cpp.
| void QgsGeometry::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.
Has no effect when called on a single point geometry.
Depending on the filter used, this may result in an invalid geometry.
Definition at line 2743 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::forceRHR | ( | ) | const |
Forces geometries to respect the Right-Hand-Rule, in which the area that is bounded by a polygon is to the right of the boundary.
In particular, the exterior ring is oriented in a clockwise direction and the interior rings in a counter-clockwise direction.
Definition at line 2418 of file qgsgeometry.cpp.
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static |
Creates a new geometry from a QgsMultiPointXY object.
Definition at line 195 of file qgsgeometry.cpp.
|
static |
Creates a new geometry from a QgsMultiPolygon.
Definition at line 215 of file qgsgeometry.cpp.
|
static |
Creates a new geometry from a QgsMultiPolylineXY object.
Definition at line 205 of file qgsgeometry.cpp.
|
static |
Creates a new geometry from a QgsPointXY object.
Definition at line 160 of file qgsgeometry.cpp.
|
static |
Creates a new geometry from a QgsPolygon.
Definition at line 185 of file qgsgeometry.cpp.
|
static |
Creates a new LineString geometry from a list of QgsPoint points.
This method will respect any Z or M dimensions present in the input points. E.g. if input points are PointZ type, the resultant linestring will be a LineStringZ type.
Definition at line 180 of file qgsgeometry.cpp.
|
static |
Creates a new LineString geometry from a list of QgsPointXY points.
Using fromPolyline() is preferred, as fromPolyline() is more efficient and will respect any Z or M dimensions present in the input points.
Definition at line 170 of file qgsgeometry.cpp.
|
static |
Construct geometry from a QPointF.
| point | source QPointF |
Definition at line 2810 of file qgsgeometry.cpp.
|
static |
Construct geometry from a QPolygonF.
If the polygon is closed than the resultant geometry will be a polygon, if it is open than the geometry will be a polyline.
| polygon | source QPolygonF |
Definition at line 2815 of file qgsgeometry.cpp.
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static |
Creates a new geometry from a QgsRectangle.
Definition at line 225 of file qgsgeometry.cpp.
| void QgsGeometry::fromWkb | ( | unsigned char * | wkb, |
| int | length | ||
| ) |
Set the geometry, feeding in the buffer containing OGC Well-Known Binary and the buffer's length.
This class will take ownership of the buffer.
Definition at line 318 of file qgsgeometry.cpp.
| void QgsGeometry::fromWkb | ( | const QByteArray & | wkb | ) |
Set the geometry, feeding in the buffer containing OGC Well-Known Binary.
Definition at line 325 of file qgsgeometry.cpp.
|
static |
Creates a new geometry from a WKT string.
Definition at line 150 of file qgsgeometry.cpp.
| QgsAbstractGeometry * QgsGeometry::get | ( | ) |
Returns a modifiable (non-const) reference to the underlying abstract geometry primitive.
This method can be slow to call, as it may trigger a detachment of the geometry and a deep copy. Where possible, use constGet() instead.
Definition at line 129 of file qgsgeometry.cpp.
| double QgsGeometry::hausdorffDistance | ( | const QgsGeometry & | geom | ) | const |
Returns the Hausdorff distance between this geometry and geom.
This is basically a measure of how similar or dissimilar 2 geometries are.
This algorithm is an approximation to the standard Hausdorff distance. This approximation is exact or close enough for a large subset of useful cases. Examples of these are:
If the default approximate provided by this method is insufficient, use hausdorffDistanceDensify() instead.
In case of error -1 will be returned.
Definition at line 1634 of file qgsgeometry.cpp.
| double QgsGeometry::hausdorffDistanceDensify | ( | const QgsGeometry & | geom, |
| double | densifyFraction | ||
| ) | const |
Returns the Hausdorff distance between this geometry and geom.
This is basically a measure of how similar or dissimilar 2 geometries are.
This function accepts a densifyFraction argument. The function performs a segment densification before computing the discrete Hausdorff distance. The densifyFraction parameter sets the fraction by which to densify each segment. Each segment will be split into a number of equal-length subsegments, whose fraction of the total length is closest to the given fraction.
This method can be used when the default approximation provided by hausdorffDistance() is not sufficient. Decreasing the densifyFraction parameter will make the distance returned approach the true Hausdorff distance for the geometries.
In case of error -1 will be returned.
Definition at line 1646 of file qgsgeometry.cpp.
| bool QgsGeometry::insertVertex | ( | double | x, |
| double | y, | ||
| int | beforeVertex | ||
| ) |
Insert a new vertex before the given vertex index, ring and item (first number is index 0) If the requested vertex number (beforeVertex.back()) is greater than the last actual vertex on the requested ring and item, it is assumed that the vertex is to be appended instead of inserted.
Returns false if atVertex does not correspond to a valid vertex on this geometry (including if this geometry is a Point). It is up to the caller to distinguish between these error conditions. (Or maybe we add another method to this object to help make the distinction?)
Definition at line 522 of file qgsgeometry.cpp.
| bool QgsGeometry::insertVertex | ( | const QgsPoint & | point, |
| int | beforeVertex | ||
| ) |
Insert a new vertex before the given vertex index, ring and item (first number is index 0) If the requested vertex number (beforeVertex.back()) is greater than the last actual vertex on the requested ring and item, it is assumed that the vertex is to be appended instead of inserted.
Returns false if atVertex does not correspond to a valid vertex on this geometry (including if this geometry is a Point). It is up to the caller to distinguish between these error conditions. (Or maybe we add another method to this object to help make the distinction?)
Definition at line 548 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::interpolate | ( | double | distance | ) | const |
Returns an interpolated point on the geometry at the specified distance.
If the original geometry is a polygon type, the boundary of the polygon will be used during interpolation. If the original geometry is a point type, a null geometry will be returned.
If z or m values are present, the output z and m will be interpolated using the existing vertices' z or m values.
If the input is a NULL geometry, the output will also be a NULL geometry.
Definition at line 2072 of file qgsgeometry.cpp.
| double QgsGeometry::interpolateAngle | ( | double | distance | ) | const |
Returns the angle parallel to the linestring or polygon boundary at the specified distance along the geometry.
Angles are in radians, clockwise from north. If the distance coincides precisely at a node then the average angle from the segment either side of the node is returned.
| distance | distance along geometry |
Definition at line 2131 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::intersection | ( | const QgsGeometry & | geometry | ) | const |
Returns a geometry representing the points shared by this geometry and other.
If the input is a NULL geometry, the output will also be a NULL geometry.
If an error was encountered while creating the result, more information can be retrieved by calling error() on the returned geometry.
Definition at line 2185 of file qgsgeometry.cpp.
| bool QgsGeometry::intersects | ( | const QgsRectangle & | rectangle | ) | const |
Returns true if this geometry exactly intersects with a rectangle.
This test is exact and can be slow for complex geometries.
The GEOS library is used to perform the intersection test. Geometries which are not valid may return incorrect results.
Definition at line 1115 of file qgsgeometry.cpp.
| bool QgsGeometry::intersects | ( | const QgsGeometry & | geometry | ) | const |
Returns true if this geometry exactly intersects with another geometry.
This test is exact and can be slow for complex geometries.
The GEOS library is used to perform the intersection test. Geometries which are not valid may return incorrect results.
Definition at line 1121 of file qgsgeometry.cpp.
| bool QgsGeometry::isEmpty | ( | ) | const |
Returns true if the geometry is empty (eg a linestring with no vertices, or a collection with no geometries).
A null geometry will always return true for isEmpty().
Definition at line 353 of file qgsgeometry.cpp.
| bool QgsGeometry::isGeosEqual | ( | const QgsGeometry & | g | ) | const |
Compares the geometry with another geometry using GEOS.
This method performs a slow, topological check, where geometries are considered equal if all of the their component edges overlap. E.g. lines with the same vertex locations but opposite direction will be considered equal by this method.
Consider using the much faster, stricter equality test performed by equals() instead.
Definition at line 2493 of file qgsgeometry.cpp.
| bool QgsGeometry::isGeosValid | ( | ) | const |
Checks validity of the geometry using GEOS.
Definition at line 2465 of file qgsgeometry.cpp.
| bool QgsGeometry::isMultipart | ( | ) | const |
Returns true if WKB of the geometry is of WKBMulti* type.
Definition at line 363 of file qgsgeometry.cpp.
| bool QgsGeometry::isNull | ( | ) | const |
| bool QgsGeometry::isSimple | ( | ) | const |
Determines whether the geometry is simple (according to OGC definition), i.e.
it has no anomalous geometric points, such as self-intersection or self-tangency. Uses GEOS library for the test.
Definition at line 2483 of file qgsgeometry.cpp.
| QString QgsGeometry::lastError | ( | ) | const |
Returns an error string referring to the last error encountered either when this geometry was created or when an operation was performed on the geometry.
Definition at line 2738 of file qgsgeometry.cpp.
| double QgsGeometry::length | ( | ) | const |
Returns the length of geometry using GEOS.
Definition at line 1605 of file qgsgeometry.cpp.
| double QgsGeometry::lineLocatePoint | ( | const QgsGeometry & | point | ) | const |
Returns a distance representing the location along this linestring of the closest point on this linestring geometry to the specified point.
Ie, the returned value indicates how far along this linestring you need to traverse to get to the closest location where this linestring comes to the specified point.
| point | point to seek proximity to |
Definition at line 2112 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::makeDifference | ( | const QgsGeometry & | other | ) | const |
Returns the geometry formed by modifying this geometry such that it does not intersect the other geometry.
| other | geometry that should not be intersect |
Definition at line 912 of file qgsgeometry.cpp.
| int QgsGeometry::makeDifferenceInPlace | ( | const QgsGeometry & | other | ) |
Changes this geometry such that it does not intersect the other geometry.
| other | geometry that should not be intersect |
Definition at line 892 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::makeValid | ( | ) | const |
Attempts to make an invalid geometry valid without losing vertices.
Already-valid geometries are returned without further intervention. In case of full or partial dimensional collapses, the output geometry may be a collection of lower-to-equal dimension geometries or a geometry of lower dimension. Single polygons may become multi-geometries in case of self-intersections. It preserves Z values, but M values will be dropped.
If an error was encountered during the process, more information can be retrieved by calling error() on the returned geometry.
Definition at line 2405 of file qgsgeometry.cpp.
| void QgsGeometry::mapToPixel | ( | const QgsMapToPixel & | mtp | ) |
Transforms the geometry from map units to pixels in place.
| mtp | map to pixel transform |
Definition at line 2580 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::mergeLines | ( | ) | const |
Merges any connected lines in a LineString/MultiLineString geometry and converts them to single line strings.
Definition at line 2226 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::minimalEnclosingCircle | ( | QgsPointXY & | center, |
| double & | radius, | ||
| unsigned int | segments = 36 |
||
| ) | const |
Returns the minimal enclosing circle for the geometry.
| center | Center of the minimal enclosing circle returneds |
| radius | Radius of the minimal enclosing circle returned |
| segments | Number of segments used to segment geometry. |
Definition at line 1055 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::minimalEnclosingCircle | ( | unsigned int | segments = 36 | ) | const |
Returns the minimal enclosing circle for the geometry.
| segments | Number of segments used to segment geometry. |
Definition at line 1082 of file qgsgeometry.cpp.
| bool QgsGeometry::moveVertex | ( | double | x, |
| double | y, | ||
| int | atVertex | ||
| ) |
Moves the vertex at the given position number and item (first number is index 0) to the given coordinates.
Returns false if atVertex does not correspond to a valid vertex on this geometry
Definition at line 453 of file qgsgeometry.cpp.
| bool QgsGeometry::moveVertex | ( | const QgsPoint & | p, |
| int | atVertex | ||
| ) |
Moves the vertex at the given position number and item (first number is index 0) to the given coordinates.
Returns false if atVertex does not correspond to a valid vertex on this geometry
Definition at line 471 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::nearestPoint | ( | const QgsGeometry & | other | ) | const |
Returns the nearest point on this geometry to another geometry.
Definition at line 596 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::offsetCurve | ( | double | distance, |
| int | segments, | ||
| JoinStyle | joinStyle, | ||
| double | miterLimit | ||
| ) | const |
Returns an offset line at a given distance and side from an input line.
| distance | buffer distance |
| segments | for round joins, number of segments to approximate quarter-circle |
| joinStyle | join style for corners in geometry |
| miterLimit | limit on the miter ratio used for very sharp corners (JoinStyleMiter only) |
Definition at line 1764 of file qgsgeometry.cpp.
|
inline |
Allows direct construction of QVariants from geometry.
Definition at line 2205 of file qgsgeometry.h.
| QgsGeometry & QgsGeometry::operator= | ( | QgsGeometry const & | rhs | ) |
Creates a deep copy of the object.
Definition at line 89 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::orientedMinimumBoundingBox | ( | double & | area, |
| double & | angle, | ||
| double & | width, | ||
| double & | height | ||
| ) | const |
Returns the oriented minimum bounding box for the geometry, which is the smallest (by area) rotated rectangle which fully encompasses the geometry.
The area, angle (clockwise in degrees from North), width and height of the rotated bounding box will also be returned.
Definition at line 942 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::orientedMinimumBoundingBox | ( | ) | const |
Returns the oriented minimum bounding box for the geometry, which is the smallest (by area) rotated rectangle which fully encompasses the geometry.
Definition at line 1001 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::orthogonalize | ( | double | tolerance = 1.0E-8, |
| int | maxIterations = 1000, |
||
| double | angleThreshold = 15.0 |
||
| ) | const |
Attempts to orthogonalize a line or polygon geometry by shifting vertices to make the geometries angles either right angles or flat lines.
This is an iterative algorithm which will loop until either the vertices are within a specified tolerance of right angles or a set number of maximum iterations is reached. The angle threshold parameter specifies how close to a right angle or straight line an angle must be before it is attempted to be straightened.
Definition at line 1090 of file qgsgeometry.cpp.
| bool QgsGeometry::overlaps | ( | const QgsGeometry & | geometry | ) | const |
Test for if geometry overlaps another (uses GEOS)
Definition at line 1217 of file qgsgeometry.cpp.
| QgsGeometryPartIterator QgsGeometry::parts | ( | ) |
Returns Java-style iterator for traversal of parts of the geometry.
This iterator can safely be used to modify parts of the geometry.
This method forces a detach. Use constParts() to avoid the detach if the parts are not going to be modified.
Definition at line 1709 of file qgsgeometry.cpp.
| QgsAbstractGeometry::part_iterator QgsGeometry::parts_begin | ( | ) |
Returns STL-style iterator pointing to the first part of the geometry.
This method forces a detach. Use const_parts_begin() to avoid the detach if the parts are not going to be modified.
Definition at line 1679 of file qgsgeometry.cpp.
| QgsAbstractGeometry::part_iterator QgsGeometry::parts_end | ( | ) |
Returns STL-style iterator pointing to the imaginary part after the last part of the geometry.
This method forces a detach. Use const_parts_begin() to avoid the detach if the parts are not going to be modified.
Definition at line 1688 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::pointOnSurface | ( | ) | const |
Returns a point guaranteed to lie on the surface of a geometry.
While the centroid() of a geometry may be located outside of the geometry itself (e.g., for concave shapes), the point on surface will always be inside the geometry.
If the input is a NULL geometry, the output will also be a NULL geometry.
If an error was encountered while creating the result, more information can be retrieved by calling error() on the returned geometry.
Definition at line 1977 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::poleOfInaccessibility | ( | double | precision, |
| double * | distanceToBoundary = nullptr |
||
| ) | const |
Calculates the approximate pole of inaccessibility for a surface, which is the most distant internal point from the boundary of the surface.
This function uses the 'polylabel' algorithm (Vladimir Agafonkin, 2016), which is an iterative approach guaranteed to find the true pole of inaccessibility within a specified tolerance. More precise tolerances require more iterations and will take longer to calculate. Optionally, the distance to the polygon boundary from the pole can be stored.
Definition at line 1992 of file qgsgeometry.cpp.
|
static |
Creates a GeometryCollection geometry containing possible polygons formed from the constituent linework of a set of geometries.
The input geometries must be fully noded (i.e. nodes exist at every common intersection of the geometries). The easiest way to ensure this is to first call unaryUnion() on the set of input geometries and then pass the result to polygonize(). An empty geometry will be returned in the case of errors.
Definition at line 2516 of file qgsgeometry.cpp.
| bool QgsGeometry::removeDuplicateNodes | ( | double | epsilon = 4 * std::numeric_limits<double>::epsilon(), |
| bool | useZValues = false |
||
| ) |
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.
Definition at line 1106 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::removeInteriorRings | ( | double | minimumAllowedArea = -1 | ) | const |
Removes the interior rings from a (multi)polygon geometry.
If the minimumAllowedArea parameter is specified then only rings smaller than this minimum area will be removed.
Definition at line 740 of file qgsgeometry.cpp.
| bool QgsGeometry::requiresConversionToStraightSegments | ( | ) | const |
Returns true if the geometry is a curved geometry type which requires conversion to display as straight line segments.
Definition at line 2546 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::reshapeGeometry | ( | const QgsLineString & | reshapeLineString | ) |
Replaces a part of this geometry with another line.
Definition at line 853 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::rotate | ( | double | rotation, |
| const QgsPointXY & | center | ||
| ) |
Rotate this geometry around the Z axis.
| rotation | clockwise rotation in degrees |
| center | rotation center |
Definition at line 789 of file qgsgeometry.cpp.
| void QgsGeometry::set | ( | QgsAbstractGeometry * | geometry | ) |
Sets the underlying geometry store.
Ownership of geometry is transferred.
Definition at line 135 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::shortestLine | ( | const QgsGeometry & | other | ) | const |
Returns the shortest line joining this geometry to another geometry.
Definition at line 605 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::simplify | ( | double | tolerance | ) | const |
Returns a simplified version of this geometry using a specified tolerance value.
Definition at line 1920 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::singleSidedBuffer | ( | double | distance, |
| int | segments, | ||
| BufferSide | side, | ||
| JoinStyle | joinStyle = JoinStyleRound, |
||
| double | miterLimit = 2.0 |
||
| ) | const |
Returns a single sided buffer for a (multi)line geometry.
The buffer is only applied to one side of the line.
| distance | buffer distance |
| segments | for round joins, number of segments to approximate quarter-circle |
| side | side of geometry to buffer |
| joinStyle | join style for corners |
| miterLimit | limit on the miter ratio used for very sharp corners |
Definition at line 1822 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::smooth | ( | unsigned int | iterations = 1, |
| double | offset = 0.25, |
||
| double | minimumDistance = -1.0, |
||
| double | maxAngle = 180.0 |
||
| ) | const |
Smooths a geometry by rounding off corners using the Chaikin algorithm.
This operation roughly doubles the number of vertices in a geometry.
If input geometries contain Z or M values, these will also be smoothed and the output geometry will retain the same dimensionality as the input geometry.
| iterations | number of smoothing iterations to run. More iterations results in a smoother geometry |
| offset | fraction of line to create new vertices along, between 0 and 1.0, e.g., the default value of 0.25 will create new vertices 25% and 75% along each line segment of the geometry for each iteration. Smaller values result in "tighter" smoothing. |
| minimumDistance | minimum segment length to apply smoothing to |
| maxAngle | maximum angle at node (0-180) at which smoothing will be applied |
Definition at line 2885 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::snappedToGrid | ( | double | hSpacing, |
| double | vSpacing, | ||
| double | dSpacing = 0, |
||
| double | mSpacing = 0 |
||
| ) | const |
Returns a new geometry with all points or vertices snapped to the closest point of the grid.
If the gridified geometry could not be calculated (or was totally collapsed) an empty geometry will be returned. Note that snapping to grid 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.
| 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. |
Definition at line 1097 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::splitGeometry | ( | const QVector< QgsPointXY > & | splitLine, |
| QVector< QgsGeometry > & | newGeometries, | ||
| bool | topological, | ||
| QVector< QgsPointXY > & | topologyTestPoints | ||
| ) |
Splits this geometry according to a given line.
| splitLine | the line that splits the geometry | |
| [out] | newGeometries | list of new geometries that have been created with the split |
| topological | true if topological editing is enabled | |
| [out] | topologyTestPoints | points that need to be tested for topological completeness in the dataset |
Definition at line 805 of file qgsgeometry.cpp.
| double QgsGeometry::sqrDistToVertexAt | ( | QgsPointXY &point | SIP_IN, |
| int | atVertex | ||
| ) | const |
Returns the squared Cartesian distance between the given point to the given vertex index (vertex at the given position number, ring and item (first number is index 0))
Definition at line 590 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::subdivide | ( | int | maxNodes = 256 | ) | const |
Subdivides the geometry.
The returned geometry will be a collection containing subdivided parts from the original geometry, where no part has more then the specified maximum number of nodes (maxNodes).
This is useful for dividing a complex geometry into less complex parts, which are better able to be spatially indexed and faster to perform further operations such as intersects on. The returned geometry parts may not be valid and may contain self-intersections.
The minimum allowed value for maxNodes is 8.
Curved geometries will be segmentized before subdivision.
If the input is a NULL geometry, the output will also be a NULL geometry.
If an error was encountered while creating the result, more information can be retrieved by calling error() on the returned geometry.
Definition at line 2045 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::symDifference | ( | const QgsGeometry & | geometry | ) | const |
Returns a geometry representing the points making up this geometry that do not make up other.
If the input is a NULL geometry, the output will also be a NULL geometry.
If an error was encountered while creating the result, more information can be retrieved by calling error() on the returned geometry.
Definition at line 2266 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::taperedBuffer | ( | double | startWidth, |
| double | endWidth, | ||
| int | segments | ||
| ) | const |
Calculates a variable width buffer ("tapered buffer") for a (multi)curve geometry.
The buffer begins at a width of startWidth at the start of each curve, and ends at a width of endWidth. Note that unlike buffer() methods, startWidth and endWidth are the diameter of the buffer at these points, not the radius.
The segments argument specifies the number of segments to approximate quarter-circle curves in the buffer.
Non (multi)curve input geometries will return a null output geometry.
Definition at line 1866 of file qgsgeometry.cpp.
| bool QgsGeometry::touches | ( | const QgsGeometry & | geometry | ) | const |
Test for if geometry touch another (uses GEOS)
Definition at line 1205 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::transform | ( | const QgsCoordinateTransform & | ct, |
| QgsCoordinateTransform::TransformDirection | direction = QgsCoordinateTransform::ForwardTransform, |
||
| bool | transformZ = false |
||
| ) |
Transforms this geometry as described by the coordinate transform ct.
The transformation defaults to a forward transform, but the direction can be swapped by setting the direction argument.
By default, z-coordinates are not transformed, even if the coordinate transform includes a vertical datum transformation. To transform z-coordinates, set transformZ to true. 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).
Definition at line 2556 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::transform | ( | const QTransform & | t, |
| double | zTranslate = 0.0, |
||
| double | zScale = 1.0, |
||
| double | mTranslate = 0.0, |
||
| double | mScale = 1.0 |
||
| ) |
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.
Definition at line 2568 of file qgsgeometry.cpp.
| void QgsGeometry::transformVertices | ( | const std::function< QgsPoint(const QgsPoint &) > & | transform | ) |
Transforms the vertices from the geometry in place, applying the transform function to every vertex.
Depending on the transform used, this may result in an invalid geometry.
Transform functions are not permitted to alter the dimensionality of vertices. If a transform which adds (or removes) z/m values is desired, first call the corresponding addZValue() or addMValue() function to change the geometry's dimensionality and then transform.
Definition at line 2753 of file qgsgeometry.cpp.
| QgsGeometry::OperationResult QgsGeometry::translate | ( | double | dx, |
| double | dy, | ||
| double | dz = 0.0, |
||
| double | dm = 0.0 |
||
| ) |
Translates this geometry by dx, dy, dz and dm.
Definition at line 776 of file qgsgeometry.cpp.
| QgsWkbTypes::GeometryType QgsGeometry::type | ( | ) | const |
Returns type of the geometry as a QgsWkbTypes::GeometryType.
|
static |
Compute the unary union on a list of geometries.
May be faster than an iterative union on a set of geometries. The returned geometry will be fully noded, i.e. a node will be created at every common intersection of the input geometries. An empty geometry will be returned in the case of errors.
Definition at line 2505 of file qgsgeometry.cpp.
| void QgsGeometry::validateGeometry | ( | QVector< QgsGeometry::Error > & | errors, |
| ValidationMethod | method = ValidatorQgisInternal |
||
| ) | const |
Validates geometry and produces a list of geometry errors.
The method argument dictates which validator to utilize.
Definition at line 2460 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::variableWidthBufferByM | ( | int | segments | ) | const |
Calculates a variable width buffer for a (multi)linestring geometry, where the width at each node is taken from the linestring m values.
The segments argument specifies the number of segments to approximate quarter-circle curves in the buffer.
Non (multi)linestring input geometries will return a null output geometry.
Definition at line 1873 of file qgsgeometry.cpp.
| QgsPoint QgsGeometry::vertexAt | ( | int | atVertex | ) | const |
Returns coordinates of a vertex.
| atVertex | index of the vertex |
Definition at line 574 of file qgsgeometry.cpp.
| bool QgsGeometry::vertexIdFromVertexNr | ( | int | number, |
| QgsVertexId & | id | ||
| ) | const |
Calculates the vertex ID from a vertex number.
If a matching vertex was found, it will be stored in id.
Returns true if vertex was found.
Definition at line 2693 of file qgsgeometry.cpp.
| int QgsGeometry::vertexNrFromVertexId | ( | QgsVertexId | id | ) | const |
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.
Definition at line 2729 of file qgsgeometry.cpp.
| QgsVertexIterator QgsGeometry::vertices | ( | ) | const |
Returns a read-only, Java-style iterator for traversal of vertices of all the geometry, including all geometry parts and rings.
Definition at line 1672 of file qgsgeometry.cpp.
| QgsAbstractGeometry::vertex_iterator QgsGeometry::vertices_begin | ( | ) | const |
Returns STL-style iterator pointing to the first vertex of the geometry.
Definition at line 1658 of file qgsgeometry.cpp.
| QgsAbstractGeometry::vertex_iterator QgsGeometry::vertices_end | ( | ) | const |
Returns STL-style iterator pointing to the imaginary vertex after the last vertex of the geometry.
Definition at line 1665 of file qgsgeometry.cpp.
| QgsGeometry QgsGeometry::voronoiDiagram | ( | const QgsGeometry & | extent = QgsGeometry(), |
| double | tolerance = 0.0, |
||
| bool | edgesOnly = false |
||
| ) | const |
Creates a Voronoi diagram for the nodes contained within the geometry.
Returns the Voronoi polygons for the nodes contained within the geometry. If extent is specified then it will be used as a clipping envelope for the diagram. If no extent is set then the clipping envelope will be automatically calculated. In either case the diagram will be clipped to the larger of the provided envelope OR the envelope surrounding all input nodes. The tolerance parameter specifies an optional snapping tolerance which can be used to improve the robustness of the diagram calculation. If edgesOnly is true than line string boundary geometries will be returned instead of polygons. An empty geometry will be returned if the diagram could not be calculated.
Definition at line 2017 of file qgsgeometry.cpp.
| bool QgsGeometry::within | ( | const QgsGeometry & | geometry | ) | const |
Test for if geometry is within another (uses GEOS)
Definition at line 1229 of file qgsgeometry.cpp.
| QgsWkbTypes::Type QgsGeometry::wkbType | ( | ) | const |
Returns type of the geometry as a WKB type (point / linestring / polygon etc.)
Definition at line 331 of file qgsgeometry.cpp.
|
friend |
Definition at line 2268 of file qgsgeometry.h.
|
read |
Definition at line 109 of file qgsgeometry.h.
|
read |
Definition at line 110 of file qgsgeometry.h.
1.8.13