Class: QgsGeometryEngine¶

class qgis.core.QgsGeometryEngine¶

Bases: sip.wrapper

Contains geometry relation and modification algorithms.

New in version 2.10: Enums

Methods

`area`
`buffer`	buffer(self, distance: float, segments: int, endCapStyle: int, joinStyle: int, miterLimit: float, errorMsg: str = ‘’) -> QgsAbstractGeometry
`centroid`	Calculates the centroid of this.
`combine`	Calculate the combination of this and `geom`.
`contains`	Checks if `geom` contains this.
`convexHull`	Calculate the convex hull of this.
`crosses`	Checks if `geom` crosses this.
`difference`	Calculate the difference of this and `geom`.
`disjoint`	Checks if `geom` is disjoint from this.
`distance`	Calculates the distance between this and `geom`.
`envelope`
`geometryChanged`	Should be called whenever the geometry associated with the engine has been modified and the engine must be updated to suit.
`interpolate`
`intersection`	Calculate the intersection of this and `geom`.
`intersects`	Checks if `geom` intersects this.
`isEmpty`
`isEqual`	Checks if this is equal to `geom`.
`isSimple`	Determines whether the geometry is simple (according to OGC definition).
`isValid`	Returns true if the geometry is valid.
`length`
`offsetCurve`
`overlaps`	Checks if `geom` overlaps this.
`pointOnSurface`	Calculate a point that is guaranteed to be on the surface of this.
`prepareGeometry`	Prepares the geometry, so that subsequent calls to spatial relation methods are much faster.
`relate`	Returns the Dimensional Extended 9 Intersection Model (DE-9IM) representation of the relationship between the geometries.
`relatePattern`	Tests whether two geometries are related by a specified Dimensional Extended 9 Intersection Model (DE-9IM) pattern.
`simplify`
`splitGeometry`	Splits this geometry according to a given line.
`symDifference`	Calculate the symmetric difference of this and `geom`.
`touches`	Checks if `geom` touches this.
`within`	Checks if `geom` is within this.

Signals

Attributes

`EngineError`
`InvalidBaseGeometry`
`InvalidInput`
`MethodNotImplemented`
`NodedGeometryError`
`NothingHappened`
`SplitCannotSplitPoint`
`Success`

EngineError = 1002¶

class EngineOperationResult¶: Bases: int

InvalidBaseGeometry = 1004¶

InvalidInput = 1005¶

MethodNotImplemented = 1001¶

NodedGeometryError = 1003¶

NothingHappened = 1000¶

SplitCannotSplitPoint = 1006¶

Success = 0¶

area(self, errorMsg: str = '') → float¶

buffer(self, distance: float, segments: int, errorMsg: str = '') → QgsAbstractGeometry¶: buffer(self, distance: float, segments: int, endCapStyle: int, joinStyle: int, miterLimit: float, errorMsg: str = ‘’) -> QgsAbstractGeometry

centroid(self, errorMsg: str = '') → QgsPoint¶: Calculates the centroid of this. May return a `None`.

New in version 3.0.

combine(self, geom: QgsAbstractGeometry, errorMsg: str = '') → QgsAbstractGeometry¶

Calculate the combination of this and geom.

New in version 3.0.

combine(self, geomList: object, errorMsg: str) -> QgsAbstractGeometry Calculate the combination of this and geometries.

New in version 3.0.

combine(self, geometries: Iterable[QgsGeometry], errorMsg: str = ‘’) -> QgsAbstractGeometry Calculate the combination of this and geometries.

New in version 3.0.

contains(self, geom: QgsAbstractGeometry, errorMsg: str = '') → bool¶: Checks if geom contains this.

New in version 3.0.

convexHull(self, errorMsg: str = '') → QgsAbstractGeometry¶: Calculate the convex hull of this.

crosses(self, geom: QgsAbstractGeometry, errorMsg: str = '') → bool¶: Checks if geom crosses this.

New in version 3.0.

difference(self, geom: QgsAbstractGeometry, errorMsg: str = '') → QgsAbstractGeometry¶: Calculate the difference of this and geom.

New in version 3.0.

disjoint(self, geom: QgsAbstractGeometry, errorMsg: str = '') → bool¶: Checks if geom is disjoint from this.

New in version 3.0.

distance(self, geom: QgsAbstractGeometry, errorMsg: str = '') → float¶: Calculates the distance between this and geom.

New in version 3.0.

envelope(self, errorMsg: str = '') → QgsAbstractGeometry¶

geometryChanged(self)¶: Should be called whenever the geometry associated with the engine has been modified and the engine must be updated to suit.

interpolate(self, distance: float, errorMsg: str = '') → QgsAbstractGeometry¶

intersection(self, geom: QgsAbstractGeometry, errorMsg: str = '') → QgsAbstractGeometry¶: Calculate the intersection of this and geom.

New in version 3.0.

intersects(self, geom: QgsAbstractGeometry, errorMsg: str = '') → bool¶: Checks if geom intersects this.

New in version 3.0.

isEmpty(self, errorMsg: str) → bool¶

isEqual(self, geom: QgsAbstractGeometry, errorMsg: str = '') → bool¶: Checks if this is equal to geom. If both are Null geometries, `False` is returned.

New in version 3.0.

isSimple(self, errorMsg: str = '') → bool¶: Determines whether the geometry is simple (according to OGC definition).

New in version 3.0.

isValid(self, errorMsg: str = '', allowSelfTouchingHoles: bool = False, errorLoc: QgsGeometry = None) → bool¶

Returns true if the geometry is valid.

If the geometry is invalid, errorMsg will be filled with the reported geometry error.

The allowSelfTouchingHoles argument specifies whether self-touching holes are permitted. OGC validity states that self-touching holes are NOT permitted, whilst other vendor validity checks (e.g. ESRI) permit self-touching holes.

If errorLoc is specified, it will be set to the geometry of the error location.

length(self, errorMsg: str = '') → float¶

offsetCurve(self, distance: float, segments: int, joinStyle: int, miterLimit: float, errorMsg: str = '') → QgsAbstractGeometry¶

overlaps(self, geom: QgsAbstractGeometry, errorMsg: str = '') → bool¶: Checks if geom overlaps this.

New in version 3.0.

pointOnSurface(self, errorMsg: str = '') → QgsPoint¶: Calculate a point that is guaranteed to be on the surface of this. May return a `None`.

New in version 3.0.

prepareGeometry(self)¶

Prepares the geometry, so that subsequent calls to spatial relation methods are much faster.

This should be called for any geometry which is used for multiple relation tests against other geometries.