Class: QgsCurvePolygon¶

class qgis.core.QgsCurvePolygon¶

Bases: qgis._core.QgsSurface

Curve polygon geometry type

New in version 2.10: Enums

Methods

`addInteriorRing`	Adds an interior ring to the geometry (takes ownership)
`addMValue`
`addZValue`
`adjacentVertices`
`area`
`asGml2`
`asGml3`
`asWkb`
`asWkt`
`boundary`
`calculateBoundingBox`
`childCount`
`childGeometry`
`childPoint`
`clear`
`clearCache`
`clone`
`closestSegment`
`coordinateSequence`
`createEmptyWithSameType`
`deleteVertex`
`dimension`
`draw`
`dropMValue`
`dropZValue`
`exteriorRing`	Returns the curve polygon’s exterior ring.
`forceRHR`	Forces the geometry to respect the Right-Hand-Rule, in which the area that is bounded by the polygon is to the right of the boundary.
`fromWkb`
`fromWkt`
`geometryType`
`hasChildGeometries`
`hasCurvedSegments`
`insertVertex`
`interiorRing`	Retrieves an interior ring from the curve polygon.
`isEmpty`
`moveVertex`
`nCoordinates`
`nextVertex`
`numInteriorRings`	Returns the number of interior rings contained with the curve polygon.
`partCount`
`perimeter`
`removeDuplicateNodes`
`removeInteriorRing`	Removes an interior ring from the polygon.
`removeInteriorRings`	Removes the interior rings from the polygon.
`removeInvalidRings`	Removes any interior rings which are not valid from the polygon.
`ringCount`
`segmentLength`
`segmentize`	Returns a geometry without curves.
`setExteriorRing`	Sets the exterior ring of the polygon.
`setInteriorRings`	Sets all interior rings (takes ownership)
`setZMTypeFromSubGeometry`
`snappedToGrid`
`surfaceToPolygon`
`swapXy`
`toCurveType`
`toPolygon`	Returns a new polygon geometry corresponding to a segmentized approximation of the curve.
`transform`	transform(self, t: QTransform, zTranslate: float = 0, zScale: float = 1, mTranslate: float = 0, mScale: float = 1)
`vertexAngle`	Returns approximate rotation angle for a vertex.
`vertexAt`
`vertexCount`
`vertexNumberFromVertexId`

Signals

Attributes

addInteriorRing(self, ring: QgsCurve)¶: Adds an interior ring to the geometry (takes ownership)

addMValue(self, mValue: float = 0) → bool¶

addZValue(self, zValue: float = 0) → bool¶

adjacentVertices(self, vertex: QgsVertexId) → Tuple[QgsVertexId, QgsVertexId]¶

area(self) → float¶

asGml2(self, doc: QDomDocument, precision: int = 17, ns: str = '', axisOrder: QgsAbstractGeometry.AxisOrder = QgsAbstractGeometry.AxisOrder.XY) → QDomElement¶

asGml3(self, doc: QDomDocument, precision: int = 17, ns: str = '', axisOrder: QgsAbstractGeometry.AxisOrder = QgsAbstractGeometry.AxisOrder.XY) → QDomElement¶

asWkb(self) → QByteArray¶

asWkt(self, precision: int = 17) → str¶

boundary(self) → QgsAbstractGeometry¶

calculateBoundingBox(self) → QgsRectangle¶

childCount(self) → int¶

childGeometry(self, index: int) → QgsAbstractGeometry¶

childPoint()¶

clear(self)¶

clearCache()¶

clone(self) → QgsCurvePolygon¶

closestSegment(self, pt: QgsPoint, epsilon: float = 4*DBL_EPSILON) → Tuple[float, QgsPoint, QgsVertexId, int]¶

coordinateSequence(self) → object¶

createEmptyWithSameType(self) → QgsCurvePolygon¶

deleteVertex(self, position: QgsVertexId) → bool¶

dimension(self) → int¶

draw(self, p: QPainter)¶

dropMValue(self) → bool¶

dropZValue(self) → bool¶

exteriorRing(self) → QgsCurve¶: Returns the curve polygon’s exterior ring.

See also

interiorRing()

forceRHR(self)¶: Forces the geometry to respect the Right-Hand-Rule, in which the area that is bounded by the 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.

New in version 3.6.

fromWkb(self, wkb: QgsConstWkbPtr) → bool¶

fromWkt(self, wkt: str) → bool¶

geometryType(self) → str¶

hasChildGeometries()¶

hasCurvedSegments(self) → bool¶

insertVertex(self, position: QgsVertexId, vertex: QgsPoint) → bool¶

interiorRing(self, i: int) → QgsCurve¶

Retrieves an interior ring from the curve polygon. The first interior ring has index 0.

An IndexError will be raised if no interior ring with the specified index exists.

See also

numInteriorRings()

See also

exteriorRing()

isEmpty(self) → bool¶

moveVertex(self, position: QgsVertexId, newPos: QgsPoint) → bool¶

nCoordinates(self) → int¶

nextVertex(self, id: QgsVertexId) → Tuple[bool, QgsPoint]¶

numInteriorRings(self) → int¶: Returns the number of interior rings contained with the curve polygon.

See also

interiorRing()

partCount(self) → int¶

perimeter(self) → float¶

removeDuplicateNodes(self, epsilon: float = 4*DBL_EPSILON, useZValues: bool = False) → bool¶

removeInteriorRing(self, i: int) → bool¶

Removes an interior ring from the polygon. The first interior ring has index 0. The corresponding ring is removed from the polygon and deleted. It is not possible to remove the exterior ring using this method.

An IndexError will be raised if no interior ring with the specified index exists.

See also

removeInteriorRings()

removeInteriorRings(self, minimumAllowedArea: float = -1)¶: Removes the interior rings from the polygon. If the minimumAllowedArea parameter is specified then only rings smaller than this minimum area will be removed.

See also

removeInteriorRing()

New in version 3.0.

removeInvalidRings(self)¶

Removes any interior rings which are not valid from the polygon.

For example, this removes unclosed rings and rings with less than 4 vertices.

New in version 3.0.

ringCount(self, part: int = 0) → int¶

segmentLength(self, startVertex: QgsVertexId) → float¶

segmentize(self, tolerance: float = M_PI_2/90, toleranceType: QgsAbstractGeometry.SegmentationToleranceType = QgsAbstractGeometry.MaximumAngle) → QgsAbstractGeometry¶

Returns a geometry without curves. Caller takes ownership

Parameters

tolerance – segmentation tolerance
toleranceType – maximum segmentation angle or maximum difference between approximation and curve*

setExteriorRing(self, ring: QgsCurve)¶

Sets the exterior ring of the polygon. The CurvePolygon type will be updated to match the dimensionality of the exterior ring. For instance, setting a 2D exterior ring on a 3D CurvePolygon will drop the z dimension from the CurvePolygon and all interior rings.

Parameters: ring – new exterior ring. Ownership is transferred to the CurvePolygon.

See also

setInteriorRings()

See also

exteriorRing()

setInteriorRings(self, rings: object)¶: Sets all interior rings (takes ownership)

setZMTypeFromSubGeometry()¶

snappedToGrid(self, hSpacing: float, vSpacing: float, dSpacing: float = 0, mSpacing: float = 0) → QgsCurvePolygon¶

surfaceToPolygon(self) → QgsPolygon¶

swapXy(self)¶

toCurveType(self) → QgsCurvePolygon¶

toPolygon(self, tolerance: float = M_PI_2/90, toleranceType: QgsAbstractGeometry.SegmentationToleranceType = QgsAbstractGeometry.MaximumAngle) → QgsPolygon¶

Returns a new polygon geometry corresponding to a segmentized approximation of the curve.

Parameters

tolerance – segmentation tolerance
toleranceType – maximum segmentation angle or maximum difference between approximation and curve*

transform(self, ct: QgsCoordinateTransform, d: QgsCoordinateTransform.TransformDirection = QgsCoordinateTransform.ForwardTransform, transformZ: bool = False)¶: transform(self, t: QTransform, zTranslate: float = 0, zScale: float = 1, mTranslate: float = 0, mScale: float = 1)

vertexAngle(self, vertex: QgsVertexId) → float¶

Returns approximate rotation angle for a vertex. Usually average angle between adjacent segments.

Parameters: vertex – the vertex id
Returns: rotation in radians, clockwise from north

vertexAt(self, id: QgsVertexId) → QgsPoint¶

vertexCount(self, part: int = 0, ring: int = 0) → int¶

vertexNumberFromVertexId(self, id: QgsVertexId) → int¶