initial commit

billinglayer/python/shapely/geometry/geo.py

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+"""
+Geometry factories based on the geo interface
+"""
+import numpy as np
+
+from shapely.errors import GeometryTypeError
+
+from .collection import GeometryCollection
+from .linestring import LineString
+from .multilinestring import MultiLineString
+from .multipoint import MultiPoint
+from .multipolygon import MultiPolygon
+from .point import Point
+from .polygon import LinearRing, Polygon
+
+
+def _is_coordinates_empty(coordinates):
+    """Helper to identify if coordinates or subset of coordinates are empty"""
+
+    if coordinates is None:
+        return True
+
+    if isinstance(coordinates, (list, tuple, np.ndarray)):
+        if len(coordinates) == 0:
+            return True
+        return all(map(_is_coordinates_empty, coordinates))
+    else:
+        return False
+
+
+def _empty_shape_for_no_coordinates(geom_type):
+    """Return empty counterpart for geom_type"""
+    if geom_type == "point":
+        return Point()
+    elif geom_type == "multipoint":
+        return MultiPoint()
+    elif geom_type == "linestring":
+        return LineString()
+    elif geom_type == "multilinestring":
+        return MultiLineString()
+    elif geom_type == "polygon":
+        return Polygon()
+    elif geom_type == "multipolygon":
+        return MultiPolygon()
+    else:
+        raise GeometryTypeError(f"Unknown geometry type: {geom_type!r}")
+
+
+def box(minx, miny, maxx, maxy, ccw=True):
+    """Returns a rectangular polygon with configurable normal vector"""
+    coords = [(maxx, miny), (maxx, maxy), (minx, maxy), (minx, miny)]
+    if not ccw:
+        coords = coords[::-1]
+    return Polygon(coords)
+
+
+def shape(context):
+    """
+    Returns a new, independent geometry with coordinates *copied* from the
+    context. Changes to the original context will not be reflected in the
+    geometry object.
+
+    Parameters
+    ----------
+    context :
+        a GeoJSON-like dict, which provides a "type" member describing the type
+        of the geometry and "coordinates" member providing a list of coordinates,
+        or an object which implements __geo_interface__.
+
+    Returns
+    -------
+    Geometry object
+
+    Examples
+    --------
+    Create a Point from GeoJSON, and then create a copy using __geo_interface__.
+
+    >>> context = {'type': 'Point', 'coordinates': [0, 1]}
+    >>> geom = shape(context)
+    >>> geom.geom_type == 'Point'
+    True
+    >>> geom.wkt
+    'POINT (0 1)'
+    >>> geom2 = shape(geom)
+    >>> geom == geom2
+    True
+    """
+    if hasattr(context, "__geo_interface__"):
+        ob = context.__geo_interface__
+    else:
+        ob = context
+    geom_type = ob.get("type").lower()
+    if "coordinates" in ob and _is_coordinates_empty(ob["coordinates"]):
+        return _empty_shape_for_no_coordinates(geom_type)
+    elif geom_type == "point":
+        return Point(ob["coordinates"])
+    elif geom_type == "linestring":
+        return LineString(ob["coordinates"])
+    elif geom_type == "linearring":
+        return LinearRing(ob["coordinates"])
+    elif geom_type == "polygon":
+        return Polygon(ob["coordinates"][0], ob["coordinates"][1:])
+    elif geom_type == "multipoint":
+        return MultiPoint(ob["coordinates"])
+    elif geom_type == "multilinestring":
+        return MultiLineString(ob["coordinates"])
+    elif geom_type == "multipolygon":
+        return MultiPolygon([[c[0], c[1:]] for c in ob["coordinates"]])
+    elif geom_type == "geometrycollection":
+        geoms = [shape(g) for g in ob.get("geometries", [])]
+        return GeometryCollection(geoms)
+    else:
+        raise GeometryTypeError(f"Unknown geometry type: {geom_type!r}")
+
+
+def mapping(ob):
+    """
+    Returns a GeoJSON-like mapping from a Geometry or any
+    object which implements __geo_interface__
+
+    Parameters
+    ----------
+    ob :
+        An object which implements __geo_interface__.
+
+    Returns
+    -------
+    dict
+
+    Examples
+    --------
+    >>> pt = Point(0, 0)
+    >>> mapping(pt)
+    {'type': 'Point', 'coordinates': (0.0, 0.0)}
+    """
+    return ob.__geo_interface__