Module transformnd.adapters.shapely

Classes

class GeometryAdapter

Transform shapely geometries.

As well as the generic __call__(), there are methods for transforming different geometry subclasses.

N.B. some transforms may create invalid topologies (incorrect winding, self-intersections etc.)

Expand source code

class GeometryAdapter(BaseAdapter[BaseGeometry]):
    """Transform shapely geometries.

    As well as the generic `__call__()`,
    there are methods for transforming different geometry subclasses.

    N.B. some transforms may create invalid topologies
    (incorrect winding, self-intersections etc.)
    """

    def transform_point(self, transform: Transform, point: Point) -> Point:
        return Point(*transform.apply(np.array(point.coords))[0])

    def transform_linestring(
        self, transform: Transform, linestring: LineString
    ) -> LineString:
        return LineString(transform.apply(np.array(linestring.coords)))

    def transform_linear_ring(
        self, transform: Transform, linear_ring: LinearRing
    ) -> LinearRing:
        return LinearRing(transform.apply(np.array(linear_ring.coords)))

    def transform_polygon(self, transform: Transform, polygon: Polygon) -> Polygon:
        return Polygon(
            self.transform_linear_ring(transform, polygon.exterior),
            [self.transform_linear_ring(transform, i) for i in polygon.interiors],
        )

    def transform_multi(self, transform: Transform, multi_geom):
        cls = type(multi_geom)
        method = {
            MultiPoint: self.transform_point,
            MultiLineString: self.transform_linestring,
            MultiPolygon: self.transform_polygon,
        }[cls]
        return cls([method(transform, obj) for obj in multi_geom])

    def apply(
        self,
        transform: Transform,
        obj: BaseGeometry,
    ) -> BaseGeometry:
        """Transform the shapely geometry.

        Parameters
        ----------
        transform : Transform
        obj : BaseGeometry
            Some shapely geometry in 2 or 3D

        Returns
        -------
        BaseGeometry
            An object of the same type as the input.
        """
        if isinstance(obj, BaseMultipartGeometry):
            return self.transform_multi(transform, obj)

        method = {
            Point: self.transform_point,
            LineString: self.transform_linestring,
            LinearRing: self.transform_linear_ring,
            Polygon: self.transform_polygon,
        }[type(obj)]
        return method(transform, obj)

Ancestors

• BaseAdapter
• typing.Generic
• abc.ABC

Methods

def apply(self, transform: Transform, obj: shapely.geometry.base.BaseGeometry) ‑> shapely.geometry.base.BaseGeometry

Transform the shapely geometry.

Parameters

transform : Transform

 

obj : BaseGeometry

Some shapely geometry in 2 or 3D

Returns

BaseGeometry

An object of the same type as the input.

Expand source code

def apply(
    self,
    transform: Transform,
    obj: BaseGeometry,
) -> BaseGeometry:
    """Transform the shapely geometry.

    Parameters
    ----------
    transform : Transform
    obj : BaseGeometry
        Some shapely geometry in 2 or 3D

    Returns
    -------
    BaseGeometry
        An object of the same type as the input.
    """
    if isinstance(obj, BaseMultipartGeometry):
        return self.transform_multi(transform, obj)

    method = {
        Point: self.transform_point,
        LineString: self.transform_linestring,
        LinearRing: self.transform_linear_ring,
        Polygon: self.transform_polygon,
    }[type(obj)]
    return method(transform, obj)

def transform_linear_ring(self, transform: Transform, linear_ring: shapely.geometry.polygon.LinearRing) ‑> shapely.geometry.polygon.LinearRing

Expand source code

def transform_linear_ring(
    self, transform: Transform, linear_ring: LinearRing
) -> LinearRing:
    return LinearRing(transform.apply(np.array(linear_ring.coords)))

def transform_linestring(self, transform: Transform, linestring: shapely.geometry.linestring.LineString) ‑> shapely.geometry.linestring.LineString

Expand source code

def transform_linestring(
    self, transform: Transform, linestring: LineString
) -> LineString:
    return LineString(transform.apply(np.array(linestring.coords)))

def transform_multi(self, transform: Transform, multi_geom)

Expand source code

def transform_multi(self, transform: Transform, multi_geom):
    cls = type(multi_geom)
    method = {
        MultiPoint: self.transform_point,
        MultiLineString: self.transform_linestring,
        MultiPolygon: self.transform_polygon,
    }[cls]
    return cls([method(transform, obj) for obj in multi_geom])

def transform_point(self, transform: Transform, point: shapely.geometry.point.Point) ‑> shapely.geometry.point.Point

Expand source code

def transform_point(self, transform: Transform, point: Point) -> Point:
    return Point(*transform.apply(np.array(point.coords))[0])

def transform_polygon(self, transform: Transform, polygon: shapely.geometry.polygon.Polygon) ‑> shapely.geometry.polygon.Polygon

Expand source code

def transform_polygon(self, transform: Transform, polygon: Polygon) -> Polygon:
    return Polygon(
        self.transform_linear_ring(transform, polygon.exterior),
        [self.transform_linear_ring(transform, i) for i in polygon.interiors],
    )

Inherited members

• BaseAdapter:
  • partial