Class: QgsMeshSpatialIndex¶

A spatial index for QgsMeshFace or QgsMeshEdge objects.

QgsMeshSpatialIndex objects are implicitly shared and can be inexpensively copied.

Note

While the underlying libspatialindex is not thread safe on some platforms, the QgsMeshSpatialIndex class implements its own locks and accordingly, a single QgsMeshSpatialIndex object can safely be used across multiple threads

See also

QgsSpatialIndex which is for vector features

Added in version 3.6.

Methods

`addFace`	Adds a face with faceIndex from the mesh in the spatial index
`elementType`	Returns the type of mesh elements that are indexed
`intersects`	Returns a list of face ids with a bounding box which intersects the specified rectangle.
`nearestNeighbor`	Returns nearest neighbors to a point.
`removeFace`	Removes a face with faceIndex from the mesh in the spatial index

class qgis.core.QgsMeshSpatialIndex[source]¶

Bases: object

__init__(): Constructor for QgsSpatialIndex. Creates an empty R-tree index.

__init__(mesh: QgsMesh, feedback: QgsFeedback | None = None, elementType: QgsMesh.ElementType = QgsMesh.ElementType.Face)

Constructor - creates R-tree and bulk loads faces or edges from the specified mesh

Not implemented to construct R-tree for vertices Since QGIS 3.14 possibility to create R-tree for edges

The optional feedback object can be used to allow cancellation of bulk face loading. Ownership of feedback is not transferred, and callers must take care that the lifetime of feedback exceeds that of the spatial index construction.

Parameters:

mesh (QgsMesh)
feedback (Optional[QgsFeedback] = None)
elementType (QgsMesh.ElementType = QgsMesh.ElementType.Face)

__init__(other: QgsMeshSpatialIndex)

Parameters:: other (QgsMeshSpatialIndex)

addFace(self, faceIndex: int, mesh: QgsMesh)[source]¶

Adds a face with faceIndex from the mesh in the spatial index

Parameters:

faceIndex (int)
mesh (QgsMesh)

elementType(self) → QgsMesh.ElementType[source]¶

Returns the type of mesh elements that are indexed

Added in version 3.14.

Return type:: QgsMesh.ElementType

intersects(self, rectangle: QgsRectangle) → List[int]¶

Returns a list of face ids with a bounding box which intersects the specified rectangle.

Note

The intersection test is performed based on the face bounding boxes only, so it is necessary to manually test the returned faces for exact geometry intersection when required.

Parameters:: rectangle (QgsRectangle)
Return type:: List[int]

nearestNeighbor(self, point: QgsPointXY, neighbors: int) → List[int]¶

Returns nearest neighbors to a point. The number of neighbours returned is specified by the neighbours argument.

Note

The nearest neighbour test is performed based on the face bounding boxes only, so this method is not guaranteed to return the actual closest neighbours.

Parameters:

point (QgsPointXY)
neighbors (int)

Return type:

List[int]

removeFace(self, faceIndex: int, mesh: QgsMesh)[source]¶

Removes a face with faceIndex from the mesh in the spatial index

Parameters:

faceIndex (int)
mesh (QgsMesh)