def flatten_geometry(geometry: BaseGeometry) -> BaseGeometry:
"""
:param geometry: Shapely geometry object
:return: geometry with Z values removed
"""
geometry_type = type(geometry)
# strip 3rd dimension
if 'POLYGON Z' in geometry.wkt:
polygons = ([polygon for polygon in geometry]
if geometry_type is MultiPolygon else [geometry])
for polygon_index, polygon in enumerate(polygons):
exterior_2d = LinearRing(
[vertex[:2] for vertex in polygon.exterior.coords])
interiors_2d = [
LinearRing([vertex[:2] for vertex in interior.coords])
for interior in polygon.interiors
]
polygons[polygon_index] = Polygon(exterior_2d, interiors_2d)
geometry = (MultiPolygon(polygons)
if geometry_type is MultiPolygon else Polygon(polygons[0]))
if not geometry.is_valid:
geometry = geometry.buffer(0)
return geometry
def stretch_contour(geom: BaseGeometry, width: float = 1) -> BaseGeometry:
"""
Stretch geometry (expected to be a geometry contour) to given width scale.
"""
if width > 1 and geom:
buf = 1 + (width - 1) / 10
return geom.buffer(buf)
return geom
def is_similar(geom1: BaseGeometry, geom2: BaseGeometry, eps: float = 1e-6) -> bool:
if type(geom1) is not type(geom2):
return False
if isinstance(geom1, (LineString, MultiLineString, Point, MultiPoint)):
return (geom1.buffer(eps).contains(geom2)
and geom2.buffer(eps).contains(geom1))
if isinstance(geom1, (Polygon, MultiPolygon)):
return geom1.symmetric_difference(geom2).area < eps
if isinstance(geom1, GeometryCollection):
polygons1, non_polygons1 = separate(geom1, lambda geom: isinstance(geom, Polygon))
polygons2, non_polygons2 = separate(geom2, lambda geom: isinstance(geom, Polygon))
polygon_union1 = unary_union(polygons1)
non_polygon_union1 = unary_union(non_polygons1)
polygon_union2 = unary_union(polygons2)
non_polygon_union2 = unary_union(non_polygons2)
return (polygon_union1.symmetric_difference(polygon_union2).area < eps
and non_polygon_union1.buffer(eps).contains(non_polygon_union2)
and non_polygon_union2.buffer(eps).contains(non_polygon_union1))
def _valid_shape(shape: BaseGeometry) -> BaseGeometry:
if shape.is_valid:
return shape
return shape.buffer(0)
