QGIS API Documentation
3.2.0-Bonn (bc43194)
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Abstract base class for all geometries. More...
#include <qgsabstractgeometry.h>
Classes | |
class | vertex_iterator |
The vertex_iterator class provides STL-style iterator for vertices. More... | |
Public Types | |
enum | AxisOrder { XY = 0, YX } |
Axis order for GML generation. More... | |
enum | SegmentationToleranceType { MaximumAngle = 0, MaximumDifference } |
Segmentation tolerance as maximum angle or maximum difference between approximation and circle. More... | |
Public Member Functions | |
QgsAbstractGeometry ()=default | |
Constructor for QgsAbstractGeometry. More... | |
QgsAbstractGeometry (const QgsAbstractGeometry &geom) | |
virtual | ~QgsAbstractGeometry ()=default |
virtual bool | addMValue (double mValue=0)=0 |
Adds a measure to the geometry, initialized to a preset value. More... | |
virtual bool | addZValue (double zValue=0)=0 |
Adds a z-dimension to the geometry, initialized to a preset value. More... | |
virtual void | adjacentVertices (QgsVertexId vertex, QgsVertexId &previousVertex, QgsVertexId &nextVertex) const =0 |
Returns the vertices adjacent to a specified vertex within a geometry. More... | |
virtual double | area () const |
Returns the area of the geometry. More... | |
virtual QDomElement | asGml2 (QDomDocument &doc, int precision=17, const QString &ns="gml", AxisOrder axisOrder=QgsAbstractGeometry::AxisOrder::XY) const =0 |
Returns a GML2 representation of the geometry. More... | |
virtual QDomElement | asGml3 (QDomDocument &doc, int precision=17, const QString &ns="gml", AxisOrder axisOrder=QgsAbstractGeometry::AxisOrder::XY) const =0 |
Returns a GML3 representation of the geometry. More... | |
virtual QString | asJson (int precision=17) const =0 |
Returns a GeoJSON representation of the geometry. More... | |
virtual QByteArray | asWkb () const =0 |
Returns a WKB representation of the geometry. More... | |
virtual QString | asWkt (int precision=17) const =0 |
Returns a WKT representation of the geometry. More... | |
virtual QgsAbstractGeometry * | boundary () const =0 |
Returns the closure of the combinatorial boundary of the geometry (ie the topological boundary of the geometry). More... | |
virtual QgsRectangle | boundingBox () const =0 |
Returns the minimal bounding box for the geometry. More... | |
virtual QgsPoint | centroid () const |
Returns the centroid of the geometry. More... | |
virtual void | clear ()=0 |
Clears the geometry, ie reset it to a null geometry. More... | |
virtual QgsAbstractGeometry * | clone () const =0 |
Clones the geometry by performing a deep copy. More... | |
virtual double | closestSegment (const QgsPoint &pt, QgsPoint &segmentPt, QgsVertexId &vertexAfter, int *leftOf=nullptr, double epsilon=4 *std::numeric_limits< double >::epsilon()) const =0 |
Searches for the closest segment of the geometry to a given point. More... | |
virtual bool | convertTo (QgsWkbTypes::Type type) |
Converts the geometry to a specified type. More... | |
virtual QgsCoordinateSequence | coordinateSequence () const =0 |
Retrieves the sequence of geometries, rings and nodes. More... | |
virtual QgsAbstractGeometry * | createEmptyWithSameType () const =0 |
Creates a new geometry with the same class and same WKB type as the original and transfers ownership. More... | |
virtual bool | deleteVertex (QgsVertexId position)=0 |
Deletes a vertex within the geometry. More... | |
virtual int | dimension () const =0 |
Returns the inherent dimension of the geometry. More... | |
virtual void | draw (QPainter &p) const =0 |
Draws the geometry using the specified QPainter. More... | |
virtual bool | dropMValue ()=0 |
Drops any measure values which exist in the geometry. More... | |
virtual bool | dropZValue ()=0 |
Drops any z-dimensions which exist in the geometry. More... | |
virtual void | filterVertices (const std::function< bool(const QgsPoint &) > &filter) |
Filters the vertices from the geometry in place, removing any which do not return true for the filter function check. More... | |
virtual bool | fromWkb (QgsConstWkbPtr &wkb)=0 |
Sets the geometry from a WKB string. More... | |
virtual bool | fromWkt (const QString &wkt)=0 |
Sets the geometry from a WKT string. More... | |
virtual QString | geometryType () const =0 |
Returns a unique string representing the geometry type. More... | |
virtual bool | hasCurvedSegments () const |
Returns true if the geometry contains curved segments. More... | |
virtual bool | insertVertex (QgsVertexId position, const QgsPoint &vertex)=0 |
Inserts a vertex into the geometry. More... | |
bool | is3D () const |
Returns true if the geometry is 3D and contains a z-value. More... | |
virtual bool | isEmpty () const |
Returns true if the geometry is empty. More... | |
bool | isMeasure () const |
Returns true if the geometry contains m values. More... | |
virtual double | length () const |
Returns the length of the geometry. More... | |
virtual bool | moveVertex (QgsVertexId position, const QgsPoint &newPos)=0 |
Moves a vertex within the geometry. More... | |
virtual int | nCoordinates () const |
Returns the number of nodes contained in the geometry. More... | |
virtual bool | nextVertex (QgsVertexId &id, QgsPoint &vertex) const =0 |
Returns next vertex id and coordinates. More... | |
virtual bool | operator!= (const QgsAbstractGeometry &other) const =0 |
QgsAbstractGeometry & | operator= (const QgsAbstractGeometry &geom) |
virtual bool | operator== (const QgsAbstractGeometry &other) const =0 |
virtual int | partCount () const =0 |
Returns count of parts contained in the geometry. More... | |
virtual double | perimeter () const |
Returns the perimeter of the geometry. More... | |
virtual bool | removeDuplicateNodes (double epsilon=4 *std::numeric_limits< double >::epsilon(), bool useZValues=false)=0 |
Removes duplicate nodes from the geometry, wherever removing the nodes does not result in a degenerate geometry. More... | |
virtual int | ringCount (int part=0) const =0 |
Returns the number of rings of which this geometry is built. More... | |
virtual QgsAbstractGeometry * | segmentize (double tolerance=M_PI/180., SegmentationToleranceType toleranceType=MaximumAngle) const |
Returns a version of the geometry without curves. More... | |
virtual double | segmentLength (QgsVertexId startVertex) const =0 |
Returns the length of the segment of the geometry which begins at startVertex. More... | |
virtual QgsAbstractGeometry * | snappedToGrid (double hSpacing, double vSpacing, double dSpacing=0, double mSpacing=0) const =0 |
Makes a new geometry with all the points or vertices snapped to the closest point of the grid. More... | |
virtual void | swapXy ()=0 |
Swaps the x and y coordinates from the geometry. More... | |
virtual QgsAbstractGeometry * | toCurveType () const =0 |
Returns the geometry converted to the more generic curve type. More... | |
virtual void | transform (const QgsCoordinateTransform &ct, QgsCoordinateTransform::TransformDirection d=QgsCoordinateTransform::ForwardTransform, bool transformZ=false) SIP_THROW(QgsCsException)=0 |
Transforms the geometry using a coordinate transform. More... | |
virtual void | transform (const QTransform &t, double zTranslate=0.0, double zScale=1.0, double mTranslate=0.0, double mScale=1.0)=0 |
Transforms the x and y components of the geometry using a QTransform object t. More... | |
virtual double | vertexAngle (QgsVertexId vertex) const =0 |
Returns approximate angle at a vertex. More... | |
virtual QgsPoint | vertexAt (QgsVertexId id) const =0 |
Returns the point corresponding to a specified vertex id. More... | |
virtual int | vertexCount (int part=0, int ring=0) const =0 |
Returns the number of vertices of which this geometry is built. More... | |
virtual int | vertexNumberFromVertexId (QgsVertexId id) const =0 |
Returns the vertex number corresponding to a vertex id. More... | |
QgsVertexIterator | vertices () const |
Returns Java-style iterator for traversal of vertices of the geometry. More... | |
vertex_iterator | vertices_begin () const |
Returns STL-style iterator pointing to the first vertex of the geometry. More... | |
vertex_iterator | vertices_end () const |
Returns STL-style iterator pointing to the imaginary vertex after the last vertex of the geometry. More... | |
QgsWkbTypes::Type | wkbType () const |
Returns the WKB type of the geometry. More... | |
QString | wktTypeStr () const |
Returns the WKT type string of the geometry. More... | |
Protected Member Functions | |
virtual QgsRectangle | calculateBoundingBox () const |
Default calculator for the minimal bounding box for the geometry. More... | |
virtual int | childCount () const |
Returns number of child geometries (for geometries with child geometries) or child points (for geometries without child geometries - i.e. More... | |
virtual QgsAbstractGeometry * | childGeometry (int index) const |
Returns pointer to child geometry (for geometries with child geometries - i.e. More... | |
virtual QgsPoint | childPoint (int index) const |
Returns point at index (for geometries without child geometries - i.e. More... | |
virtual void | clearCache () const |
Clears any cached parameters associated with the geometry, e.g., bounding boxes. More... | |
virtual bool | hasChildGeometries () const |
Returns whether the geometry has any child geometries (false for point / curve, true otherwise) More... | |
void | setZMTypeFromSubGeometry (const QgsAbstractGeometry *subggeom, QgsWkbTypes::Type baseGeomType) |
Updates the geometry type based on whether sub geometries contain z or m values. More... | |
Protected Attributes | |
QgsWkbTypes::Type | mWkbType = QgsWkbTypes::Unknown |
Friends | |
class | TestQgsGeometry |
Abstract base class for all geometries.
Definition at line 53 of file qgsabstractgeometry.h.
Axis order for GML generation.
Enumerator | |
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XY | X comes before Y (or lon before lat) |
YX | Y comes before X (or lat before lon) |
Definition at line 110 of file qgsabstractgeometry.h.
Segmentation tolerance as maximum angle or maximum difference between approximation and circle.
Definition at line 94 of file qgsabstractgeometry.h.
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default |
Constructor for QgsAbstractGeometry.
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virtualdefault |
QgsAbstractGeometry::QgsAbstractGeometry | ( | const QgsAbstractGeometry & | geom | ) |
Definition at line 26 of file qgsabstractgeometry.cpp.
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pure virtual |
Adds a measure to the geometry, initialized to a preset value.
mValue | initial m-value for all nodes |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
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pure virtual |
Adds a z-dimension to the geometry, initialized to a preset value.
zValue | initial z-value for all nodes |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
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pure virtual |
Returns the vertices adjacent to a specified vertex within a geometry.
Implemented in QgsPoint, QgsCurvePolygon, QgsCurve, and QgsGeometryCollection.
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virtual |
Returns the area of the geometry.
Reimplemented in QgsGeometryCollection, and QgsCurvePolygon.
Definition at line 140 of file qgsabstractgeometry.cpp.
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pure virtual |
Returns a GML2 representation of the geometry.
doc | DOM document |
precision | number of decimal places for coordinates |
ns | XML namespace |
axisOrder | Axis order for generated GML |
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsCurvePolygon, QgsCompoundCurve, QgsMultiPoint, QgsMultiCurve, QgsMultiLineString, QgsMultiSurface, and QgsMultiPolygon.
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pure virtual |
Returns a GML3 representation of the geometry.
doc | DOM document |
precision | number of decimal places for coordinates |
ns | XML namespace |
axisOrder | Axis order for generated GML |
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsTriangle, QgsCurvePolygon, QgsCompoundCurve, QgsMultiPoint, QgsMultiCurve, QgsMultiLineString, QgsMultiSurface, and QgsMultiPolygon.
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pure virtual |
Returns a GeoJSON representation of the geometry.
precision | number of decimal places for coordinates |
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsCurvePolygon, QgsCompoundCurve, QgsMultiPoint, QgsMultiCurve, QgsMultiLineString, QgsMultiSurface, and QgsMultiPolygon.
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pure virtual |
Returns a WKB representation of the geometry.
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsCurvePolygon, QgsCompoundCurve, and QgsPolygon.
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pure virtual |
Returns a WKT representation of the geometry.
precision | number of decimal places for coordinates |
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsCurvePolygon, and QgsCompoundCurve.
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pure virtual |
Returns the closure of the combinatorial boundary of the geometry (ie the topological boundary of the geometry).
For instance, a polygon geometry will have a boundary consisting of the linestrings for each ring in the polygon.
Implemented in QgsPoint, QgsCurve, QgsTriangle, QgsGeometryCollection, QgsCurvePolygon, QgsPolygon, QgsMultiCurve, QgsMultiPolygon, QgsMultiPoint, and QgsMultiSurface.
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pure virtual |
Returns the minimal bounding box for the geometry.
Implemented in QgsPoint, QgsCurve, QgsGeometryCollection, and QgsSurface.
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protectedvirtual |
Default calculator for the minimal bounding box for the geometry.
Derived classes should override this method if a more efficient bounding box calculation is available.
Reimplemented in QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
Definition at line 83 of file qgsabstractgeometry.cpp.
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virtual |
Returns the centroid of the geometry.
Reimplemented in QgsLineString.
Definition at line 155 of file qgsabstractgeometry.cpp.
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inlineprotectedvirtual |
Returns number of child geometries (for geometries with child geometries) or child points (for geometries without child geometries - i.e.
curve / point)
Reimplemented in QgsPoint, QgsCurve, QgsCurvePolygon, and QgsGeometryCollection.
Definition at line 687 of file qgsabstractgeometry.h.
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inlineprotectedvirtual |
Returns pointer to child geometry (for geometries with child geometries - i.e.
geom. collection / polygon)
Reimplemented in QgsCurvePolygon, and QgsGeometryCollection.
Definition at line 694 of file qgsabstractgeometry.h.
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Returns point at index (for geometries without child geometries - i.e.
curve / point)
Reimplemented in QgsPoint, and QgsCurve.
Definition at line 253 of file qgsabstractgeometry.cpp.
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pure virtual |
Clears the geometry, ie reset it to a null geometry.
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsTriangle, QgsCurvePolygon, QgsCompoundCurve, QgsMultiPoint, QgsPolygon, QgsMultiLineString, QgsMultiCurve, QgsMultiPolygon, and QgsMultiSurface.
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protectedvirtual |
Clears any cached parameters associated with the geometry, e.g., bounding boxes.
Reimplemented in QgsCurve, QgsGeometryCollection, and QgsSurface.
Definition at line 110 of file qgsabstractgeometry.cpp.
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pure virtual |
Clones the geometry by performing a deep copy.
Implemented in QgsPoint, QgsLineString, QgsCircularString, QgsTriangle, QgsCurve, QgsCurvePolygon, QgsGeometryCollection, QgsCompoundCurve, QgsPolygon, QgsMultiLineString, QgsMultiPoint, QgsMultiPolygon, QgsMultiSurface, and QgsMultiCurve.
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pure virtual |
Searches for the closest segment of the geometry to a given point.
pt | specifies the point to find closest segment to |
segmentPt | storage for the closest point within the geometry |
vertexAfter | storage for the ID of the vertex at the end of the closest segment |
leftOf | indicates whether the point lies on the left side of the geometry (-1 if point is to the left of the geometry, +1 if the point is to the right of the geometry, or 0 for cases where left/right could not be determined, e.g. point exactly on a line) false if point is to right of segment) |
epsilon | epsilon for segment snapping |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
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virtual |
Converts the geometry to a specified type.
Reimplemented in QgsPoint, and QgsLineString.
Definition at line 207 of file qgsabstractgeometry.cpp.
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pure virtual |
Retrieves the sequence of geometries, rings and nodes.
Implemented in QgsPoint, QgsCurvePolygon, QgsCurve, and QgsGeometryCollection.
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pure virtual |
Creates a new geometry with the same class and same WKB type as the original and transfers ownership.
To create it, the geometry is default constructed and then the WKB is changed.
Implemented in QgsPoint, QgsTriangle, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, QgsCompoundCurve, QgsPolygon, QgsMultiCurve, QgsMultiSurface, QgsMultiPoint, QgsMultiLineString, and QgsMultiPolygon.
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pure virtual |
Deletes a vertex within the geometry.
position | vertex id for vertex to delete |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, QgsCompoundCurve, and QgsTriangle.
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pure virtual |
Returns the inherent dimension of the geometry.
For example, this is 0 for a point geometry, 1 for a linestring and 2 for a polygon.
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsCurvePolygon, and QgsCompoundCurve.
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pure virtual |
Draws the geometry using the specified QPainter.
p | destination QPainter |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsCircularString, QgsGeometryCollection, and QgsCompoundCurve.
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pure virtual |
Drops any measure values which exist in the geometry.
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
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pure virtual |
Drops any z-dimensions which exist in the geometry.
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
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virtual |
Filters the vertices from the geometry in place, removing any which do not return true for the filter function check.
Has no meaning when called on a single point geometry.
Depending on the filter used, this may result in an invalid geometry.
Reimplemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, QgsCompoundCurve, and QgsMultiPoint.
Definition at line 238 of file qgsabstractgeometry.cpp.
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pure virtual |
Sets the geometry from a WKB string.
After successful read the wkb argument will be at the position where the reading has stopped.
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsTriangle, QgsCurvePolygon, QgsCompoundCurve, and QgsPolygon.
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pure virtual |
Sets the geometry from a WKT string.
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsTriangle, QgsCurvePolygon, QgsCompoundCurve, QgsMultiCurve, QgsMultiLineString, QgsMultiPoint, QgsMultiSurface, and QgsMultiPolygon.
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pure virtual |
Returns a unique string representing the geometry type.
Implemented in QgsPoint, QgsLineString, QgsGeometryCollection, QgsCircularString, QgsTriangle, QgsCurvePolygon, QgsCompoundCurve, QgsPolygon, QgsMultiLineString, QgsMultiPoint, QgsMultiCurve, QgsMultiPolygon, and QgsMultiSurface.
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protectedvirtual |
Returns whether the geometry has any child geometries (false for point / curve, true otherwise)
Definition at line 248 of file qgsabstractgeometry.cpp.
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virtual |
Returns true if the geometry contains curved segments.
Reimplemented in QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
Definition at line 266 of file qgsabstractgeometry.cpp.
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pure virtual |
Inserts a vertex into the geometry.
position | vertex id for position of inserted vertex |
vertex | vertex to insert |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, QgsCompoundCurve, and QgsTriangle.
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inline |
Returns true if the geometry is 3D and contains a z-value.
Definition at line 184 of file qgsabstractgeometry.h.
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virtual |
Returns true if the geometry is empty.
Reimplemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsCircularString, QgsGeometryCollection, and QgsCompoundCurve.
Definition at line 259 of file qgsabstractgeometry.cpp.
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inline |
Returns true if the geometry contains m values.
Definition at line 193 of file qgsabstractgeometry.h.
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virtual |
Returns the length of the geometry.
Reimplemented in QgsLineString, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
Definition at line 130 of file qgsabstractgeometry.cpp.
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pure virtual |
Moves a vertex within the geometry.
position | vertex id for vertex to move |
newPos | new position of vertex |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, QgsCompoundCurve, and QgsTriangle.
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virtual |
Returns the number of nodes contained in the geometry.
Reimplemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, and QgsMultiPoint.
Definition at line 114 of file qgsabstractgeometry.cpp.
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pure virtual |
Returns next vertex id and coordinates.
id | initial value should be the starting vertex id. The next vertex id will be stored in this variable if found. |
vertex | container for found node |
Implemented in QgsPoint, QgsCurvePolygon, QgsGeometryCollection, and QgsCurve.
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pure virtual |
Implemented in QgsPoint, QgsCurve, QgsGeometryCollection, and QgsCurvePolygon.
QgsAbstractGeometry & QgsAbstractGeometry::operator= | ( | const QgsAbstractGeometry & | geom | ) |
Definition at line 31 of file qgsabstractgeometry.cpp.
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pure virtual |
Implemented in QgsPoint, QgsCurve, QgsGeometryCollection, and QgsCurvePolygon.
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pure virtual |
Returns count of parts contained in the geometry.
Implemented in QgsPoint, QgsCurvePolygon, QgsCurve, and QgsGeometryCollection.
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virtual |
Returns the perimeter of the geometry.
Reimplemented in QgsGeometryCollection, and QgsCurvePolygon.
Definition at line 135 of file qgsabstractgeometry.cpp.
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pure virtual |
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.
Implemented in QgsPoint, QgsLineString, QgsCircularString, QgsGeometryCollection, QgsCompoundCurve, and QgsCurvePolygon.
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pure virtual |
Returns the number of rings of which this geometry is built.
Implemented in QgsPoint, QgsCurvePolygon, QgsCurve, and QgsGeometryCollection.
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virtual |
Returns a version of the geometry without curves.
Caller takes ownership of the returned geometry.
tolerance | segmentation tolerance |
toleranceType | maximum segmentation angle or maximum difference between approximation and curve |
Reimplemented in QgsCurvePolygon, QgsCurve, and QgsGeometryCollection.
Definition at line 271 of file qgsabstractgeometry.cpp.
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pure virtual |
Returns the length of the segment of the geometry which begins at startVertex.
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, QgsCompoundCurve, and QgsMultiPoint.
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protected |
Updates the geometry type based on whether sub geometries contain z or m values.
Definition at line 41 of file qgsabstractgeometry.cpp.
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pure virtual |
Makes a new geometry with all the points or vertices snapped to the closest point of the grid.
Ownership is transferred to the caller.
If the gridified geometry could not be calculated a nullptr will be returned. It may generate an invalid geometry (in some corner cases). It can also be thought as rounding the edges and it may be useful for removing errors. Example:
In this case we use a 2D grid of 1x1 to gridify. In this case, it can be thought like rounding the x and y of all the points/vertices to full units (remove all decimals).
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. |
Implemented in QgsPoint, QgsLineString, QgsCircularString, QgsGeometryCollection, QgsCompoundCurve, and QgsCurvePolygon.
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pure virtual |
Swaps the x and y coordinates from the geometry.
This can be used to repair geometries which have accidentally had their latitude and longitude coordinates reversed.
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
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pure virtual |
Returns the geometry converted to the more generic curve type.
E.g. QgsLineString -> QgsCompoundCurve, QgsPolygon -> QgsCurvePolygon, QgsMultiLineString -> QgsMultiCurve, QgsMultiPolygon -> QgsMultiSurface
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCurve, QgsTriangle, QgsMultiLineString, QgsMultiPolygon, QgsPolygon, QgsMultiCurve, QgsMultiPoint, and QgsMultiSurface.
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pure virtual |
Transforms the geometry using a coordinate transform.
ct | coordinate transform |
d | transformation direction |
transformZ | set to true to also transform z coordinates. This requires that the z coordinates in the geometry represent height relative to the vertical datum of the source CRS (generally ellipsoidal heights) and are expressed in its vertical units (generally meters). If false, then z coordinates will not be changed by the transform. |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsCircularString, QgsCompoundCurve, and QgsGeometryCollection.
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pure virtual |
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.
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsCircularString, QgsCompoundCurve, and QgsGeometryCollection.
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pure virtual |
Returns approximate angle at a vertex.
This is usually the average angle between adjacent segments, and can be pictured as the orientation of a line following the curvature of the geometry at the specified vertex.
vertex | the vertex id |
Implemented in QgsPoint, QgsLineString, QgsCurvePolygon, QgsGeometryCollection, QgsCircularString, and QgsCompoundCurve.
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pure virtual |
Returns the point corresponding to a specified vertex id.
Implemented in QgsPoint, QgsCurvePolygon, QgsCurve, and QgsGeometryCollection.
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pure virtual |
Returns the number of vertices of which this geometry is built.
Implemented in QgsPoint, QgsCurvePolygon, QgsCurve, and QgsGeometryCollection.
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pure virtual |
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.
Implemented in QgsPoint, QgsCurvePolygon, QgsCurve, QgsGeometryCollection, and QgsMultiPoint.
QgsVertexIterator QgsAbstractGeometry::vertices | ( | ) | const |
Returns Java-style iterator for traversal of vertices of the geometry.
Definition at line 243 of file qgsabstractgeometry.cpp.
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inline |
Returns STL-style iterator pointing to the first vertex of the geometry.
Definition at line 644 of file qgsabstractgeometry.h.
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inline |
Returns STL-style iterator pointing to the imaginary vertex after the last vertex of the geometry.
Definition at line 653 of file qgsabstractgeometry.h.
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inline |
Returns the WKB type of the geometry.
Definition at line 171 of file qgsabstractgeometry.h.
QString QgsAbstractGeometry::wktTypeStr | ( | ) | const |
Returns the WKT type string of the geometry.
Definition at line 145 of file qgsabstractgeometry.cpp.
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friend |
Definition at line 722 of file qgsabstractgeometry.h.
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protected |
Definition at line 704 of file qgsabstractgeometry.h.