QGIS API Documentation  3.5.0-Master (bc98f86)
Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
QgsGeometryCollection Class Reference

Geometry collection. More...

#include <qgsgeometrycollection.h>

Inheritance diagram for QgsGeometryCollection:
Inheritance graph
[legend]

Public Member Functions

 QgsGeometryCollection ()
 
 QgsGeometryCollection (const QgsGeometryCollection &c)
 
 ~QgsGeometryCollection () override
 
virtual bool addGeometry (QgsAbstractGeometry *g)
 Adds a geometry and takes ownership. Returns true in case of success. More...
 
bool addMValue (double mValue=0) override
 Adds a measure to the geometry, initialized to a preset value. More...
 
bool addZValue (double zValue=0) override
 Adds a z-dimension to the geometry, initialized to a preset value. More...
 
void adjacentVertices (QgsVertexId vertex, QgsVertexId &previousVertex, QgsVertexId &nextVertex) const override
 Returns the vertices adjacent to a specified vertex within a geometry. More...
 
double area () const override
 Returns the area of the geometry. More...
 
QDomElement asGml2 (QDomDocument &doc, int precision=17, const QString &ns="gml", QgsAbstractGeometry::AxisOrder axisOrder=QgsAbstractGeometry::AxisOrder::XY) const override
 Returns a GML2 representation of the geometry. More...
 
QDomElement asGml3 (QDomDocument &doc, int precision=17, const QString &ns="gml", QgsAbstractGeometry::AxisOrder axisOrder=QgsAbstractGeometry::AxisOrder::XY) const override
 Returns a GML3 representation of the geometry. More...
 
QString asJson (int precision=17) const override
 Returns a GeoJSON representation of the geometry. More...
 
QByteArray asWkb () const override
 Returns a WKB representation of the geometry. More...
 
QString asWkt (int precision=17) const override
 Returns a WKT representation of the geometry. More...
 
QgsAbstractGeometryboundary () const override
 Returns the closure of the combinatorial boundary of the geometry (ie the topological boundary of the geometry). More...
 
QgsRectangle boundingBox () const override
 Returns the minimal bounding box for the geometry. More...
 
const QgsGeometryCollectioncast (const QgsAbstractGeometry *geom) const
 Cast the geom to a QgsGeometryCollection. More...
 
void clear () override
 Clears the geometry, ie reset it to a null geometry. More...
 
QgsGeometryCollectionclone () const override
 Clones the geometry by performing a deep copy. More...
 
double closestSegment (const QgsPoint &pt, QgsPoint &segmentPt, QgsVertexId &vertexAfter, int *leftOf=nullptr, double epsilon=4 *std::numeric_limits< double >::epsilon()) const override
 Searches for the closest segment of the geometry to a given point. More...
 
QgsCoordinateSequence coordinateSequence () const override
 Retrieves the sequence of geometries, rings and nodes. More...
 
QgsGeometryCollectioncreateEmptyWithSameType () const override
 Creates a new geometry with the same class and same WKB type as the original and transfers ownership. More...
 
bool deleteVertex (QgsVertexId position) override
 Deletes a vertex within the geometry. More...
 
int dimension () const override
 Returns the inherent dimension of the geometry. More...
 
void draw (QPainter &p) const override
 Draws the geometry using the specified QPainter. More...
 
bool dropMValue () override
 Drops any measure values which exist in the geometry. More...
 
bool dropZValue () override
 Drops any z-dimensions which exist in the geometry. More...
 
void filterVertices (const std::function< bool(const QgsPoint &) > &filter) override
 Filters the vertices from the geometry in place, removing any which do not return true for the filter function check. More...
 
bool fromWkb (QgsConstWkbPtr &wkb) override
 Sets the geometry from a WKB string. More...
 
bool fromWkt (const QString &wkt) override
 Sets the geometry from a WKT string. More...
 
const QgsAbstractGeometrygeometryN (int n) const
 Returns a const reference to a geometry from within the collection. More...
 
QgsAbstractGeometrygeometryN (int n)
 Returns a geometry from within the collection. More...
 
QString geometryType () const override
 Returns a unique string representing the geometry type. More...
 
bool hasCurvedSegments () const override
 Returns true if the geometry contains curved segments. More...
 
virtual bool insertGeometry (QgsAbstractGeometry *g, int index)
 Inserts a geometry before a specified index and takes ownership. More...
 
bool insertVertex (QgsVertexId position, const QgsPoint &vertex) override
 Inserts a vertex into the geometry. More...
 
bool isEmpty () const override
 Returns true if the geometry is empty. More...
 
double length () const override
 Returns the length of the geometry. More...
 
bool moveVertex (QgsVertexId position, const QgsPoint &newPos) override
 Moves a vertex within the geometry. More...
 
int nCoordinates () const override
 Returns the number of nodes contained in the geometry. More...
 
bool nextVertex (QgsVertexId &id, QgsPoint &vertex) const override
 Returns next vertex id and coordinates. More...
 
int numGeometries () const
 Returns the number of geometries within the collection. More...
 
bool operator!= (const QgsAbstractGeometry &other) const override
 
QgsGeometryCollectionoperator= (const QgsGeometryCollection &c)
 
bool operator== (const QgsAbstractGeometry &other) const override
 
int partCount () const override
 Returns count of parts contained in the geometry. More...
 
double perimeter () const override
 Returns the perimeter of the geometry. More...
 
bool removeDuplicateNodes (double epsilon=4 *std::numeric_limits< double >::epsilon(), bool useZValues=false) override
 Removes duplicate nodes from the geometry, wherever removing the nodes does not result in a degenerate geometry. More...
 
virtual bool removeGeometry (int nr)
 Removes a geometry from the collection. More...
 
int ringCount (int part=0) const override
 Returns the number of rings of which this geometry is built. More...
 
QgsAbstractGeometrysegmentize (double tolerance=M_PI_2/90, SegmentationToleranceType toleranceType=MaximumAngle) const override
 Returns a geometry without curves. More...
 
double segmentLength (QgsVertexId startVertex) const override
 Returns the length of the segment of the geometry which begins at startVertex. More...
 
QgsGeometryCollectionsnappedToGrid (double hSpacing, double vSpacing, double dSpacing=0, double mSpacing=0) const override
 Makes a new geometry with all the points or vertices snapped to the closest point of the grid. More...
 
void swapXy () override
 Swaps the x and y coordinates from the geometry. More...
 
QgsGeometryCollectiontoCurveType () const override
 Returns the geometry converted to the more generic curve type. More...
 
void transform (const QgsCoordinateTransform &ct, QgsCoordinateTransform::TransformDirection d=QgsCoordinateTransform::ForwardTransform, bool transformZ=false) override SIP_THROW(QgsCsException)
 Transforms the geometry using a coordinate transform. More...
 
void transform (const QTransform &t, double zTranslate=0.0, double zScale=1.0, double mTranslate=0.0, double mScale=1.0) override
 Transforms the x and y components of the geometry using a QTransform object t. More...
 
void transformVertices (const std::function< QgsPoint(const QgsPoint &) > &transform) override
 Transforms the vertices from the geometry in place, applying the transform function to every vertex. More...
 
double vertexAngle (QgsVertexId vertex) const override
 Returns approximate angle at a vertex. More...
 
QgsPoint vertexAt (QgsVertexId id) const override
 Returns the point corresponding to a specified vertex id. More...
 
int vertexCount (int part=0, int ring=0) const override
 Returns the number of vertices of which this geometry is built. More...
 
int vertexNumberFromVertexId (QgsVertexId id) const override
 Returns the vertex number corresponding to a vertex id. More...
 
- Public Member Functions inherited from QgsAbstractGeometry
 QgsAbstractGeometry ()=default
 Constructor for QgsAbstractGeometry. More...
 
 QgsAbstractGeometry (const QgsAbstractGeometry &geom)
 
virtual ~QgsAbstractGeometry ()=default
 
virtual QgsPoint centroid () const
 Returns the centroid of the geometry. More...
 
const_part_iterator const_parts_begin () const
 Returns STL-style iterator pointing to the const first part of the geometry. More...
 
const_part_iterator const_parts_end () const
 Returns STL-style iterator pointing to the imaginary const part after the last part of the geometry. More...
 
virtual bool convertTo (QgsWkbTypes::Type type)
 Converts the geometry to a specified type. More...
 
bool is3D () const
 Returns true if the geometry is 3D and contains a z-value. More...
 
bool isMeasure () const
 Returns true if the geometry contains m values. More...
 
QgsAbstractGeometryoperator= (const QgsAbstractGeometry &geom)
 
QgsGeometryConstPartIterator parts () const
 Returns Java-style iterator for traversal of parts of the geometry. More...
 
QgsGeometryPartIterator parts ()
 Returns Java-style iterator for traversal of parts of the geometry. More...
 
part_iterator parts_begin ()
 Returns STL-style iterator pointing to the first part of the geometry. More...
 
part_iterator parts_end ()
 Returns STL-style iterator pointing to the imaginary part after the last part of the geometry. 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...
 
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

QgsRectangle calculateBoundingBox () const override
 Default calculator for the minimal bounding box for the geometry. More...
 
int childCount () const override
 Returns number of child geometries (for geometries with child geometries) or child points (for geometries without child geometries - i.e. More...
 
QgsAbstractGeometrychildGeometry (int index) const override
 Returns pointer to child geometry (for geometries with child geometries - i.e. More...
 
void clearCache () const override
 Clears any cached parameters associated with the geometry, e.g., bounding boxes. More...
 
bool fromCollectionWkt (const QString &wkt, const QVector< QgsAbstractGeometry *> &subtypes, const QString &defaultChildWkbType=QString())
 Reads a collection from a WKT string. More...
 
virtual bool wktOmitChildType () const
 Returns whether child type names are omitted from Wkt representations of the collection. More...
 
- Protected Member Functions inherited from QgsAbstractGeometry
virtual QgsPoint childPoint (int index) const
 Returns point at index (for geometries without child geometries - i.e. 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

QVector< QgsAbstractGeometry *> mGeometries
 
- Protected Attributes inherited from QgsAbstractGeometry
QgsWkbTypes::Type mWkbType = QgsWkbTypes::Unknown
 

Additional Inherited Members

- Public Types inherited from QgsAbstractGeometry
enum  AxisOrder { XY = 0, YX }
 Axis order for GML generation. More...
 
enum  SegmentationToleranceType { MaximumAngle = 0, MaximumDifference }
 Segmentation tolerance as maximum angle or maximum difference between approximation and circle. More...
 

Detailed Description

Geometry collection.

Since
QGIS 2.10

Definition at line 35 of file qgsgeometrycollection.h.

Constructor & Destructor Documentation

◆ QgsGeometryCollection() [1/2]

QgsGeometryCollection::QgsGeometryCollection ( )

Definition at line 31 of file qgsgeometrycollection.cpp.

◆ QgsGeometryCollection() [2/2]

QgsGeometryCollection::QgsGeometryCollection ( const QgsGeometryCollection c)

Definition at line 36 of file qgsgeometrycollection.cpp.

◆ ~QgsGeometryCollection()

QgsGeometryCollection::~QgsGeometryCollection ( )
override

Definition at line 62 of file qgsgeometrycollection.cpp.

Member Function Documentation

◆ addGeometry()

bool QgsGeometryCollection::addGeometry ( QgsAbstractGeometry g)
virtual

Adds a geometry and takes ownership. Returns true in case of success.

Reimplemented in QgsMultiPoint, QgsMultiCurve, QgsMultiLineString, QgsMultiSurface, and QgsMultiPolygon.

Definition at line 203 of file qgsgeometrycollection.cpp.

◆ addMValue()

bool QgsGeometryCollection::addMValue ( double  mValue = 0)
overridevirtual

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

Parameters
mValueinitial m-value for all nodes
Returns
true on success
See also
dropMValue()
addZValue()
Since
QGIS 2.12

Implements QgsAbstractGeometry.

Definition at line 779 of file qgsgeometrycollection.cpp.

◆ addZValue()

bool QgsGeometryCollection::addZValue ( double  zValue = 0)
overridevirtual

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

Parameters
zValueinitial z-value for all nodes
Returns
true on success
See also
dropZValue()
addMValue()
Since
QGIS 2.12

Implements QgsAbstractGeometry.

Definition at line 764 of file qgsgeometrycollection.cpp.

◆ adjacentVertices()

void QgsGeometryCollection::adjacentVertices ( QgsVertexId  vertex,
QgsVertexId previousVertex,
QgsVertexId nextVertex 
) const
overridevirtual

Returns the vertices adjacent to a specified vertex within a geometry.

Since
QGIS 3.0

Implements QgsAbstractGeometry.

Definition at line 146 of file qgsgeometrycollection.cpp.

◆ area()

double QgsGeometryCollection::area ( ) const
overridevirtual

Returns the area of the geometry.

See also
length()
perimeter()

Reimplemented from QgsAbstractGeometry.

Definition at line 589 of file qgsgeometrycollection.cpp.

◆ asGml2()

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

Returns a GML2 representation of the geometry.

Parameters
docDOM document
precisionnumber of decimal places for coordinates
nsXML namespace
axisOrderAxis order for generated GML
See also
asWkb()
asWkt()
asGml3()
asJson()

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiPoint, QgsMultiCurve, QgsMultiLineString, QgsMultiSurface, and QgsMultiPolygon.

Definition at line 383 of file qgsgeometrycollection.cpp.

◆ asGml3()

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

Returns a GML3 representation of the geometry.

Parameters
docDOM document
precisionnumber of decimal places for coordinates
nsXML namespace
axisOrderAxis order for generated GML
See also
asWkb()
asWkt()
asGml2()
asJson()

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiPoint, QgsMultiCurve, QgsMultiLineString, QgsMultiSurface, and QgsMultiPolygon.

Definition at line 395 of file qgsgeometrycollection.cpp.

◆ asJson()

QString QgsGeometryCollection::asJson ( int  precision = 17) const
overridevirtual

Returns a GeoJSON representation of the geometry.

Parameters
precisionnumber of decimal places for coordinates
See also
asWkb()
asWkt()
asGml2()
asGml3()

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiPoint, QgsMultiCurve, QgsMultiLineString, QgsMultiSurface, and QgsMultiPolygon.

Definition at line 407 of file qgsgeometrycollection.cpp.

◆ asWkb()

QByteArray QgsGeometryCollection::asWkb ( ) const
overridevirtual

Returns a WKB representation of the geometry.

See also
asWkt
asGml2
asGml3
asJson()
Since
QGIS 3.0

Implements QgsAbstractGeometry.

Definition at line 336 of file qgsgeometrycollection.cpp.

◆ asWkt()

QString QgsGeometryCollection::asWkt ( int  precision = 17) const
overridevirtual

Returns a WKT representation of the geometry.

Parameters
precisionnumber of decimal places for coordinates
See also
asWkb()
asGml2()
asGml3()
asJson()

Implements QgsAbstractGeometry.

Definition at line 363 of file qgsgeometrycollection.cpp.

◆ boundary()

QgsAbstractGeometry * QgsGeometryCollection::boundary ( ) const
overridevirtual

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.

Returns
boundary for geometry. May be null for some geometry types.
Since
QGIS 3.0

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiCurve, QgsMultiPolygon, QgsMultiPoint, and QgsMultiSurface.

Definition at line 141 of file qgsgeometrycollection.cpp.

◆ boundingBox()

QgsRectangle QgsGeometryCollection::boundingBox ( ) const
overridevirtual

Returns the minimal bounding box for the geometry.

Implements QgsAbstractGeometry.

Definition at line 422 of file qgsgeometrycollection.cpp.

◆ calculateBoundingBox()

QgsRectangle QgsGeometryCollection::calculateBoundingBox ( ) const
overrideprotectedvirtual

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 from QgsAbstractGeometry.

Definition at line 431 of file qgsgeometrycollection.cpp.

◆ cast()

const QgsGeometryCollection* QgsGeometryCollection::cast ( const QgsAbstractGeometry geom) const
inline

Cast the geom to a QgsGeometryCollection.

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

Note
Not available in Python. Objects will be automatically be converted to the appropriate target type.
Since
QGIS 3.0

Definition at line 222 of file qgsgeometrycollection.h.

◆ childCount()

int QgsGeometryCollection::childCount ( ) const
overrideprotectedvirtual

Returns number of child geometries (for geometries with child geometries) or child points (for geometries without child geometries - i.e.

curve / point)

Note
used for vertex_iterator implementation
Since
QGIS 3.0

Reimplemented from QgsAbstractGeometry.

Definition at line 868 of file qgsgeometrycollection.cpp.

◆ childGeometry()

QgsAbstractGeometry * QgsGeometryCollection::childGeometry ( int  index) const
overrideprotectedvirtual

Returns pointer to child geometry (for geometries with child geometries - i.e.

geom. collection / polygon)

Note
used for vertex_iterator implementation
Since
QGIS 3.0

Reimplemented from QgsAbstractGeometry.

Definition at line 873 of file qgsgeometrycollection.cpp.

◆ clear()

void QgsGeometryCollection::clear ( )
overridevirtual

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

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiPoint, QgsMultiLineString, QgsMultiCurve, QgsMultiPolygon, and QgsMultiSurface.

Definition at line 105 of file qgsgeometrycollection.cpp.

◆ clearCache()

void QgsGeometryCollection::clearCache ( ) const
overrideprotectedvirtual

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

Reimplemented from QgsAbstractGeometry.

Definition at line 447 of file qgsgeometrycollection.cpp.

◆ clone()

QgsGeometryCollection * QgsGeometryCollection::clone ( ) const
overridevirtual

Clones the geometry by performing a deep copy.

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiLineString, QgsMultiPoint, QgsMultiPolygon, QgsMultiSurface, and QgsMultiCurve.

Definition at line 100 of file qgsgeometrycollection.cpp.

◆ closestSegment()

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

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

Parameters
ptspecifies the point to find closest segment to
segmentPtstorage for the closest point within the geometry
vertexAfterstorage for the ID of the vertex at the end of the closest segment
leftOfindicates 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)
epsilonepsilon for segment snapping
Returns
squared distance to closest segment or negative value on error

Implements QgsAbstractGeometry.

Definition at line 484 of file qgsgeometrycollection.cpp.

◆ coordinateSequence()

QgsCoordinateSequence QgsGeometryCollection::coordinateSequence ( ) const
overridevirtual

Retrieves the sequence of geometries, rings and nodes.

Returns
coordinate sequence

Implements QgsAbstractGeometry.

Definition at line 453 of file qgsgeometrycollection.cpp.

◆ createEmptyWithSameType()

QgsGeometryCollection * QgsGeometryCollection::createEmptyWithSameType ( ) const
overridevirtual

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

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

See also
clone()
Since
3.0

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiCurve, QgsMultiSurface, QgsMultiPoint, QgsMultiLineString, and QgsMultiPolygon.

Definition at line 93 of file qgsgeometrycollection.cpp.

◆ deleteVertex()

bool QgsGeometryCollection::deleteVertex ( QgsVertexId  position)
overridevirtual

Deletes a vertex within the geometry.

Parameters
positionvertex id for vertex to delete
Returns
true if delete was successful
See also
insertVertex
moveVertex

Implements QgsAbstractGeometry.

Definition at line 550 of file qgsgeometrycollection.cpp.

◆ dimension()

int QgsGeometryCollection::dimension ( ) const
overridevirtual

Returns the inherent dimension of the geometry.

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

Implements QgsAbstractGeometry.

Definition at line 241 of file qgsgeometrycollection.cpp.

◆ draw()

void QgsGeometryCollection::draw ( QPainter &  p) const
overridevirtual

Draws the geometry using the specified QPainter.

Parameters
pdestination QPainter

Implements QgsAbstractGeometry.

Definition at line 279 of file qgsgeometrycollection.cpp.

◆ dropMValue()

bool QgsGeometryCollection::dropMValue ( )
overridevirtual

Drops any measure values which exist in the geometry.

Returns
true if m-values were present and have been removed
See also
addMValue()
dropZValue()
Since
QGIS 2.14

Implements QgsAbstractGeometry.

Definition at line 809 of file qgsgeometrycollection.cpp.

◆ dropZValue()

bool QgsGeometryCollection::dropZValue ( )
overridevirtual

Drops any z-dimensions which exist in the geometry.

Returns
true if Z values were present and have been removed
See also
addZValue()
dropMValue()
Since
QGIS 2.14

Implements QgsAbstractGeometry.

Definition at line 795 of file qgsgeometrycollection.cpp.

◆ filterVertices()

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

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.

Note
Not available in Python bindings
Since
QGIS 3.2

Reimplemented from QgsAbstractGeometry.

Reimplemented in QgsMultiPoint.

Definition at line 823 of file qgsgeometrycollection.cpp.

◆ fromCollectionWkt()

bool QgsGeometryCollection::fromCollectionWkt ( const QString &  wkt,
const QVector< QgsAbstractGeometry *> &  subtypes,
const QString &  defaultChildWkbType = QString() 
)
protected

Reads a collection from a WKT string.

Definition at line 611 of file qgsgeometrycollection.cpp.

◆ fromWkb()

bool QgsGeometryCollection::fromWkb ( QgsConstWkbPtr wkb)
overridevirtual

Sets the geometry from a WKB string.

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

See also
fromWkt

Implements QgsAbstractGeometry.

Definition at line 288 of file qgsgeometrycollection.cpp.

◆ fromWkt()

bool QgsGeometryCollection::fromWkt ( const QString &  wkt)
overridevirtual

Sets the geometry from a WKT string.

See also
fromWkb

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiCurve, QgsMultiLineString, QgsMultiPoint, QgsMultiSurface, and QgsMultiPolygon.

Definition at line 326 of file qgsgeometrycollection.cpp.

◆ geometryN() [1/2]

const QgsAbstractGeometry* QgsGeometryCollection::geometryN ( int  n) const
inline

Returns a const reference to a geometry from within the collection.

Parameters
nindex of geometry to return
Note
not available in Python bindings

Definition at line 79 of file qgsgeometrycollection.h.

◆ geometryN() [2/2]

QgsAbstractGeometry * QgsGeometryCollection::geometryN ( int  n)

Returns a geometry from within the collection.

Parameters
nindex of geometry to return

Definition at line 184 of file qgsgeometrycollection.cpp.

◆ geometryType()

QString QgsGeometryCollection::geometryType ( ) const
overridevirtual

Returns a unique string representing the geometry type.

See also
wkbType
wktTypeStr

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiLineString, QgsMultiPoint, QgsMultiCurve, QgsMultiPolygon, and QgsMultiSurface.

Definition at line 256 of file qgsgeometrycollection.cpp.

◆ hasCurvedSegments()

bool QgsGeometryCollection::hasCurvedSegments ( ) const
overridevirtual

Returns true if the geometry contains curved segments.

Reimplemented from QgsAbstractGeometry.

Definition at line 672 of file qgsgeometrycollection.cpp.

◆ insertGeometry()

bool QgsGeometryCollection::insertGeometry ( QgsAbstractGeometry g,
int  index 
)
virtual

Inserts a geometry before a specified index and takes ownership.

Returns true in case of success.

Parameters
ggeometry to insert. Ownership is transferred to the collection.
indexposition to insert geometry before

Reimplemented in QgsMultiPoint, QgsMultiCurve, QgsMultiLineString, QgsMultiSurface, and QgsMultiPolygon.

Definition at line 215 of file qgsgeometrycollection.cpp.

◆ insertVertex()

bool QgsGeometryCollection::insertVertex ( QgsVertexId  position,
const QgsPoint vertex 
)
overridevirtual

Inserts a vertex into the geometry.

Parameters
positionvertex id for position of inserted vertex
vertexvertex to insert
Returns
true if insert was successful
See also
moveVertex
deleteVertex

Implements QgsAbstractGeometry.

Definition at line 520 of file qgsgeometrycollection.cpp.

◆ isEmpty()

bool QgsGeometryCollection::isEmpty ( ) const
overridevirtual

Returns true if the geometry is empty.

Reimplemented from QgsAbstractGeometry.

Definition at line 190 of file qgsgeometrycollection.cpp.

◆ length()

double QgsGeometryCollection::length ( ) const
overridevirtual

Returns the length of the geometry.

See also
area()
perimeter()

Reimplemented from QgsAbstractGeometry.

Definition at line 578 of file qgsgeometrycollection.cpp.

◆ moveVertex()

bool QgsGeometryCollection::moveVertex ( QgsVertexId  position,
const QgsPoint newPos 
)
overridevirtual

Moves a vertex within the geometry.

Parameters
positionvertex id for vertex to move
newPosnew position of vertex
Returns
true if move was successful
See also
insertVertex
deleteVertex

Implements QgsAbstractGeometry.

Definition at line 535 of file qgsgeometrycollection.cpp.

◆ nCoordinates()

int QgsGeometryCollection::nCoordinates ( ) const
overridevirtual

Returns the number of nodes contained in the geometry.

Reimplemented from QgsAbstractGeometry.

Reimplemented in QgsMultiPoint.

Definition at line 471 of file qgsgeometrycollection.cpp.

◆ nextVertex()

bool QgsGeometryCollection::nextVertex ( QgsVertexId id,
QgsPoint vertex 
) const
overridevirtual

Returns next vertex id and coordinates.

Parameters
idinitial value should be the starting vertex id. The next vertex id will be stored in this variable if found.
vertexcontainer for found node
Returns
false if at end

Implements QgsAbstractGeometry.

Definition at line 489 of file qgsgeometrycollection.cpp.

◆ numGeometries()

int QgsGeometryCollection::numGeometries ( ) const
inline

Returns the number of geometries within the collection.

Definition at line 51 of file qgsgeometrycollection.h.

◆ operator!=()

bool QgsGeometryCollection::operator!= ( const QgsAbstractGeometry other) const
overridevirtual

Implements QgsAbstractGeometry.

Definition at line 88 of file qgsgeometrycollection.cpp.

◆ operator=()

QgsGeometryCollection & QgsGeometryCollection::operator= ( const QgsGeometryCollection c)

Definition at line 46 of file qgsgeometrycollection.cpp.

◆ operator==()

bool QgsGeometryCollection::operator== ( const QgsAbstractGeometry other) const
overridevirtual

Implements QgsAbstractGeometry.

Definition at line 67 of file qgsgeometrycollection.cpp.

◆ partCount()

int QgsGeometryCollection::partCount ( ) const
overridevirtual

Returns count of parts contained in the geometry.

See also
vertexCount
ringCount

Implements QgsAbstractGeometry.

Definition at line 754 of file qgsgeometrycollection.cpp.

◆ perimeter()

double QgsGeometryCollection::perimeter ( ) const
overridevirtual

Returns the perimeter of the geometry.

See also
area()
length()

Reimplemented from QgsAbstractGeometry.

Definition at line 600 of file qgsgeometrycollection.cpp.

◆ removeDuplicateNodes()

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

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

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

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

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

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

Since
QGIS 3.0

Implements QgsAbstractGeometry.

Definition at line 131 of file qgsgeometrycollection.cpp.

◆ removeGeometry()

bool QgsGeometryCollection::removeGeometry ( int  nr)
virtual

Removes a geometry from the collection.

Parameters
nrindex of geometry to remove
Returns
true if removal was successful.

Definition at line 229 of file qgsgeometrycollection.cpp.

◆ ringCount()

int QgsGeometryCollection::ringCount ( int  part = 0) const
overridevirtual

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

Implements QgsAbstractGeometry.

Definition at line 744 of file qgsgeometrycollection.cpp.

◆ segmentize()

QgsAbstractGeometry * QgsGeometryCollection::segmentize ( double  tolerance = M_PI_2 / 90,
SegmentationToleranceType  toleranceType = MaximumAngle 
) const
overridevirtual

Returns a geometry without curves.

Caller takes ownership

Parameters
tolerancesegmentation tolerance
toleranceTypemaximum segmentation angle or maximum difference between approximation and curve

Reimplemented from QgsAbstractGeometry.

Definition at line 685 of file qgsgeometrycollection.cpp.

◆ segmentLength()

double QgsGeometryCollection::segmentLength ( QgsVertexId  startVertex) const
overridevirtual

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

Since
QGIS 3.0

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiPoint.

Definition at line 718 of file qgsgeometrycollection.cpp.

◆ snappedToGrid()

QgsGeometryCollection * QgsGeometryCollection::snappedToGrid ( double  hSpacing,
double  vSpacing,
double  dSpacing = 0,
double  mSpacing = 0 
) const
overridevirtual

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

Ownership is transferred to the caller.

If the gridified geometry could not be calculated 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:

geometry->snappedToGrid(1, 1);

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

Parameters
hSpacingHorizontal spacing of the grid (x axis). 0 to disable.
vSpacingVertical spacing of the grid (y axis). 0 to disable.
dSpacingDepth spacing of the grid (z axis). 0 (default) to disable.
mSpacingCustom dimension spacing of the grid (m axis). 0 (default) to disable.
Since
3.0

Implements QgsAbstractGeometry.

Definition at line 112 of file qgsgeometrycollection.cpp.

◆ swapXy()

void QgsGeometryCollection::swapXy ( )
overridevirtual

Swaps the x and y coordinates from the geometry.

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

Since
QGIS 3.2

Implements QgsAbstractGeometry.

Definition at line 843 of file qgsgeometrycollection.cpp.

◆ toCurveType()

QgsGeometryCollection * QgsGeometryCollection::toCurveType ( ) const
overridevirtual

Returns the geometry converted to the more generic curve type.

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

Returns
the converted geometry. Caller takes ownership

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiLineString, QgsMultiPolygon, QgsMultiCurve, QgsMultiPoint, and QgsMultiSurface.

Definition at line 853 of file qgsgeometrycollection.cpp.

◆ transform() [1/2]

void QgsGeometryCollection::transform ( const QgsCoordinateTransform ct,
QgsCoordinateTransform::TransformDirection  d = QgsCoordinateTransform::ForwardTransform,
bool  transformZ = false 
)
overridevirtual

Transforms the geometry using a coordinate transform.

Parameters
ctcoordinate transform
dtransformation direction
transformZset to true to also transform z coordinates. This requires that the z coordinates in the geometry represent height relative to the vertical datum of the source CRS (generally ellipsoidal heights) and are expressed in its vertical units (generally meters). If false, then z coordinates will not be changed by the transform.

Implements QgsAbstractGeometry.

Definition at line 261 of file qgsgeometrycollection.cpp.

◆ transform() [2/2]

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

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

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

Implements QgsAbstractGeometry.

Definition at line 270 of file qgsgeometrycollection.cpp.

◆ transformVertices()

void QgsGeometryCollection::transformVertices ( const std::function< QgsPoint(const QgsPoint &) > &  transform)
overridevirtual

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.

Note
Not available in Python bindings
Since
QGIS 3.4

Reimplemented from QgsAbstractGeometry.

Definition at line 833 of file qgsgeometrycollection.cpp.

◆ vertexAngle()

double QgsGeometryCollection::vertexAngle ( QgsVertexId  vertex) const
overridevirtual

Returns approximate angle at a vertex.

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

Parameters
vertexthe vertex id
Returns
rotation in radians, clockwise from north

Implements QgsAbstractGeometry.

Definition at line 702 of file qgsgeometrycollection.cpp.

◆ vertexAt()

QgsPoint QgsGeometryCollection::vertexAt ( QgsVertexId  id) const
overridevirtual

Returns the point corresponding to a specified vertex id.

Implements QgsAbstractGeometry.

Definition at line 759 of file qgsgeometrycollection.cpp.

◆ vertexCount()

int QgsGeometryCollection::vertexCount ( int  part = 0,
int  ring = 0 
) const
overridevirtual

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

Implements QgsAbstractGeometry.

Definition at line 734 of file qgsgeometrycollection.cpp.

◆ vertexNumberFromVertexId()

int QgsGeometryCollection::vertexNumberFromVertexId ( QgsVertexId  id) const
overridevirtual

Returns the vertex number corresponding to a vertex id.

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

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

Since
QGIS 3.0

Implements QgsAbstractGeometry.

Reimplemented in QgsMultiPoint.

Definition at line 158 of file qgsgeometrycollection.cpp.

◆ wktOmitChildType()

bool QgsGeometryCollection::wktOmitChildType ( ) const
protectedvirtual

Returns whether child type names are omitted from Wkt representations of the collection.

Since
QGIS 2.12

Reimplemented in QgsMultiPoint, QgsMultiLineString, and QgsMultiPolygon.

Definition at line 863 of file qgsgeometrycollection.cpp.

Member Data Documentation

◆ mGeometries

QVector< QgsAbstractGeometry * > QgsGeometryCollection::mGeometries
protected

Definition at line 299 of file qgsgeometrycollection.h.


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