# This file is part of the Open Data Cube, see https://opendatacube.org for more information
#
# Copyright (c) 2015-2020 ODC Contributors
# SPDX-License-Identifier: Apache-2.0
import array
import functools
import itertools
import math
import warnings
from collections import abc
from typing import (
Any,
Callable,
Dict,
Iterable,
Iterator,
List,
Optional,
Sequence,
Tuple,
Union,
)
import numpy
from affine import Affine
from shapely import geometry, ops
from shapely.geometry import base
from .crs import CRS, CRSMismatchError, MaybeCRS, SomeCRS, norm_crs, norm_crs_or_error
from .types import SomeShape, SupportsCoords, shape_
CoordList = List[Tuple[float, float]]
# pylint: disable=too-many-lines,too-many-public-methods
[docs]class BoundingBox(Sequence[float]):
"""Bounding box, defining extent in cartesian coordinates."""
__slots__ = "_crs", "_box"
[docs] def __init__(
self, left: float, bottom: float, right: float, top: float, crs: MaybeCRS = None
):
self._box = (left, bottom, right, top)
self._crs = norm_crs(crs)
@property
def left(self):
return self._box[0]
@property
def bottom(self):
return self._box[1]
@property
def right(self):
return self._box[2]
@property
def top(self):
return self._box[3]
@property
def crs(self) -> Optional[CRS]:
return self._crs
@property
def bbox(self) -> Tuple[float, float, float, float]:
return self._box
def __iter__(self):
return self._box.__iter__()
def __eq__(self, other: Any) -> bool:
if isinstance(other, BoundingBox):
return self._crs == other._crs and self._box == other._box
return self._box == other
def __hash__(self) -> int:
return hash((self._crs, self._box))
def __len__(self) -> int:
return 4
def __getitem__(self, idx):
return self._box[idx]
def __repr__(self) -> str:
if self.crs is None:
return f"BoundingBox(left={self.left}, bottom={self.bottom}, right={self.right}, top={self.top})"
return (
f"BoundingBox(left={self.left}, bottom={self.bottom},"
f" right={self.right}, top={self.top}, crs={repr(self.crs)})"
)
def __str__(self) -> str:
return self.__repr__()
[docs] def buffered(self, xbuff: float, ybuff: Optional[float] = None) -> "BoundingBox":
"""
Return a new BoundingBox, buffered in the x and y dimensions.
:param xbuff: X dimension buffering amount
:param ybuff: Y dimension buffering amount
:return: new BoundingBox
"""
if ybuff is None:
ybuff = xbuff
return BoundingBox(
left=self.left - xbuff,
bottom=self.bottom - ybuff,
right=self.right + xbuff,
top=self.top + ybuff,
crs=self._crs,
)
@property
def span_x(self) -> float:
"""Span of the bounding box along x axis."""
return self.right - self.left
@property
def span_y(self) -> float:
"""Span of the bounding box along y axis."""
return self.top - self.bottom
@property
def aspect(self) -> float:
"""Aspect ratio."""
return self.span_x / self.span_y
@property
def width(self) -> int:
"""``int(span_x)``"""
return int(self.right - self.left)
@property
def height(self) -> int:
"""``int(span_y)``"""
return int(self.top - self.bottom)
@property
def shape(self) -> Tuple[int, int]:
"""``(int(span_y), int(span_x))``."""
return (self.height, self.width)
@property
def range_x(self) -> Tuple[float, float]:
"""``left, right``"""
return (self.left, self.right)
@property
def range_y(self) -> Tuple[float, float]:
"""``bottom, top``"""
return (self.bottom, self.top)
@property
def points(self) -> CoordList:
"""Extract four corners of the bounding box."""
x0, y0, x1, y1 = self._box
return list(itertools.product((x0, x1), (y0, y1)))
def to_crs(self, crs: SomeCRS, **kw) -> "BoundingBox":
"""
Compute bounding box in other CRS.
"""
return self.polygon.to_crs(crs, **kw).boundingbox
def map_bounds(self) -> Tuple[Tuple[float, float], Tuple[float, float]]:
"""
Convert to bounds in folium/ipyleaflet style.
Returns SW, and NE corners in lat/lon order.
``((lat_w, lon_s), (lat_e, lon_n))``.
"""
x0, y0, x1, y1 = self._box
if self._crs == "epsg:4326" or self._crs is None:
return (y0, x0), (y1, x1)
(x0, y0), _, (x1, y1) = self.polygon.exterior.to_crs("epsg:4326").points[:3]
return (y0, x0), (y1, x1)
@property
def polygon(self) -> "Geometry":
return box(*self.bbox, self.crs)
[docs] @staticmethod
def from_xy(
x: Tuple[float, float], y: Tuple[float, float], crs: MaybeCRS = None
) -> "BoundingBox":
"""
Construct :py:class:`~odc.geo.geom.BoundingBox` from x and y ranges.
:param x: (left, right)
:param y: (bottom, top)
:param crs: CRS
"""
x1, x2 = sorted(x)
y1, y2 = sorted(y)
return BoundingBox(x1, y1, x2, y2, crs)
[docs] @staticmethod
def from_points(
p1: Tuple[float, float], p2: Tuple[float, float], crs: MaybeCRS = None
) -> "BoundingBox":
"""
Construct :py:class:`~odc.geo.geom.BoundingBox` from two points.
:param p1: (x, y)
:param p2: (x, y)
:param crs: CRS
"""
return BoundingBox.from_xy((p1[0], p2[0]), (p1[1], p2[1]), crs)
def wrap_shapely(method):
"""
Takes a method that expects shapely geometry arguments and converts it to a method that operates
on :py:class:`odc.geo.geom.Geometry` objects that carry their CRSs.
"""
@functools.wraps(method, assigned=("__doc__",))
def wrapped(*args):
first = args[0]
for arg in args[1:]:
if first.crs != arg.crs:
raise CRSMismatchError((first.crs, arg.crs))
result = method(*[arg.geom for arg in args])
if isinstance(result, base.BaseGeometry):
return Geometry(result, first.crs)
return result
return wrapped
def force_2d(geojson: Dict[str, Any]) -> Dict[str, Any]:
assert "type" in geojson
assert "coordinates" in geojson
def is_scalar(x):
return isinstance(x, (int, float))
def go(x):
if is_scalar(x):
return x
if isinstance(x, abc.Sequence):
if all(is_scalar(y) for y in x):
return x[:2]
return [go(y) for y in x]
raise ValueError(f"invalid coordinate {x}")
return {"type": geojson["type"], "coordinates": go(geojson["coordinates"])}
[docs]def densify(coords: CoordList, resolution: float) -> CoordList:
"""
Adds points so they are at most `resolution` units apart.
"""
d2 = resolution**2
def short_enough(p1, p2):
return (p1[0] ** 2 + p2[0] ** 2) < d2
new_coords = [coords[0]]
for p1, p2 in zip(coords[:-1], coords[1:]):
if not short_enough(p1, p2):
segment = geometry.LineString([p1, p2])
segment_length = segment.length
d = resolution
while d < segment_length:
(pt,) = segment.interpolate(d).coords
new_coords.append(pt)
d += resolution
new_coords.append(p2)
return new_coords
def _clone_shapely_geom(geom: base.BaseGeometry) -> base.BaseGeometry:
return type(geom)(geom)
[docs]class Geometry(SupportsCoords[float]):
"""
2D Geometry with CRS.
This is a wrapper around :py:class:`shapely.geometry.BaseGeometry` that adds projection information.
Instantiate with a GeoJSON structure. If 3D coordinates are supplied, they are converted to 2D
by dropping the Z points.
"""
# pylint: disable=protected-access, multiple-statements
[docs] def __init__(
self,
geom: Union[base.BaseGeometry, Dict[str, Any], "Geometry"],
crs: MaybeCRS = None,
):
if isinstance(geom, Geometry):
assert crs is None
self.crs: Optional[CRS] = geom.crs
self.geom: base.BaseGeometry = _clone_shapely_geom(geom.geom)
return
crs = norm_crs(crs)
self.crs = crs
if isinstance(geom, base.BaseGeometry):
self.geom = geom
elif isinstance(geom, dict):
self.geom = geometry.shape(force_2d(geom))
else:
raise ValueError(f"Unexpected type {type(geom)}")
def clone(self) -> "Geometry":
return Geometry(self)
# fmt: off
@wrap_shapely
def contains(self, other: "Geometry") -> bool: return self.contains(other)
@wrap_shapely
def crosses(self, other: "Geometry") -> bool: return self.crosses(other)
@wrap_shapely
def disjoint(self, other: "Geometry") -> bool: return self.disjoint(other)
@wrap_shapely
def intersects(self, other: "Geometry") -> bool: return self.intersects(other)
@wrap_shapely
def touches(self, other: "Geometry") -> bool: return self.touches(other)
@wrap_shapely
def within(self, other: "Geometry") -> bool: return self.within(other)
@wrap_shapely
def overlaps(self, other: "Geometry") -> bool: return self.overlaps(other)
@wrap_shapely
def difference(self, other: "Geometry") -> "Geometry": return self.difference(other)
@wrap_shapely
def intersection(self, other: "Geometry") -> "Geometry": return self.intersection(other)
@wrap_shapely
def symmetric_difference(self, other: "Geometry") -> "Geometry": return self.symmetric_difference(other)
@wrap_shapely
def union(self, other: "Geometry") -> "Geometry": return self.union(other)
@wrap_shapely
def __and__(self, other: "Geometry") -> "Geometry": return self.__and__(other)
@wrap_shapely
def __or__(self, other: "Geometry") -> "Geometry": return self.__or__(other)
@wrap_shapely
def __xor__(self, other: "Geometry") -> "Geometry": return self.__xor__(other)
@wrap_shapely
def __sub__(self, other: "Geometry") -> "Geometry": return self.__sub__(other)
def svg(self, *args, **kw) -> str: return self.geom.svg(*args, *kw)
def _repr_svg_(self) -> str: return self.geom._repr_svg_()
@property
def type(self) -> str: return self.geom.type
@property
def is_empty(self) -> bool: return self.geom.is_empty
@property
def is_valid(self) -> bool: return self.geom.is_valid
@property
def is_ring(self) -> bool: return self.geom.is_ring
@property
def boundary(self) -> "Geometry": return Geometry(self.geom.boundary, self.crs)
@property
def exterior(self) -> "Geometry": return Geometry(self.geom.exterior, self.crs)
@property
def interiors(self) -> List["Geometry"]: return [Geometry(g, self.crs) for g in self.geom.interiors]
@property
def centroid(self) -> "Geometry": return Geometry(self.geom.centroid, self.crs)
@property
def coords(self) -> CoordList: return list(self.geom.coords)
@property
def points(self) -> CoordList: return self.coords
@property
def length(self) -> float: return self.geom.length
@property
def area(self) -> float: return self.geom.area
@property
def xy(self) -> Tuple[array.array, array.array]: return self.geom.xy
@property
def convex_hull(self) -> "Geometry": return Geometry(self.geom.convex_hull, self.crs)
@property
def envelope(self) -> "Geometry": return Geometry(self.geom.envelope, self.crs)
@property
def boundingbox(self) -> BoundingBox:
minx, miny, maxx, maxy = self.geom.bounds
return BoundingBox(left=minx, right=maxx, bottom=miny, top=maxy, crs=self.crs)
@property
def wkt(self) -> str: return self.geom.wkt
@property
def __geo_interface__(self): return self.geom.__geo_interface__
# fmt: on
@property
def json(self):
return self.__geo_interface__
def segmented(self, resolution: float) -> "Geometry":
"""
Increase resolution of the geometry.
Possibly add more points to the geometry so that no edge is longer than ``resolution``.
"""
def segmentize_shapely(geom: base.BaseGeometry) -> base.BaseGeometry:
if geom.type in ["Point", "MultiPoint"]:
return type(geom)(geom) # clone without changes
if geom.type in ["GeometryCollection", "MultiPolygon", "MultiLineString"]:
return type(geom)([segmentize_shapely(g) for g in geom.geoms])
if geom.type in ["LineString", "LinearRing"]:
return type(geom)(densify(list(geom.coords), resolution))
if geom.type == "Polygon":
return geometry.Polygon(
densify(list(geom.exterior.coords), resolution),
[densify(list(i.coords), resolution) for i in geom.interiors],
)
raise ValueError(f"unknown geometry type {geom.type}") # pragma: no cover
return Geometry(segmentize_shapely(self.geom), self.crs)
def interpolate(self, distance: float) -> "Geometry":
"""
Returns a point ``distance`` units along the line.
@raises :py:class:`TypeError` if geometry doesn't support this operation.
"""
return Geometry(self.geom.interpolate(distance), self.crs)
def buffer(self, distance: float, resolution: float = 30) -> "Geometry":
return Geometry(self.geom.buffer(distance, resolution=resolution), self.crs)
def simplify(self, tolerance: float, preserve_topology: bool = True) -> "Geometry":
return Geometry(
self.geom.simplify(tolerance, preserve_topology=preserve_topology), self.crs
)
def transform(self, func) -> "Geometry":
"""
Map through arbitrary transform.
Applies ``func`` to all coordinates of :py:class:`~odc.geo.geom.Geometry` and returns a new
Geometry of the same type and in the same projection from the transformed coordinates.
``func`` maps ``x, y``, and optionally ``z`` to output ``xp, yp, zp``. The input parameters
may be iterable types like lists or arrays or single values. The output shall be of the same
type: scalars in, scalars out; lists in, lists out.
"""
if isinstance(func, Affine):
def _tr(A, x, y):
_xy = [A * xy for xy in zip(x, y)]
return [x for x, _ in _xy], [y for _, y in _xy]
_geom = ops.transform(functools.partial(_tr, func), self.geom)
else:
_geom = ops.transform(func, self.geom)
return Geometry(_geom, self.crs)
def _to_crs(self, crs: CRS) -> "Geometry":
assert self.crs is not None
return Geometry(ops.transform(self.crs.transformer_to_crs(crs), self.geom), crs)
[docs] def to_crs(
self,
crs: SomeCRS,
resolution: Optional[float] = None,
wrapdateline: bool = False,
) -> "Geometry":
"""
Convert geometry to a different Coordinate Reference System.
:param crs:
CRS to convert to
:param resolution:
When supplied, increase resolution of the geometry before projecting.
This is done by adding extra points such that no segment is longer
than ``resolution`` units in the source CRS of the geometry.
Reasonable value for the parameter depends on the application. Lower
value will result in higher precision, but larger output geometry and
slower processing.
Consider using :py:meth:`~odc.geo.geom.Geometry.simplify` on the
output of this function to reduce the size of the ouptut, especially
when using high precision transform.
If not supplied project the geometry as is without adding any extra points.
:param wrapdateline:
Attempt to gracefully handle geometry that intersects the dateline when converting to
geographic projections. Currently only works in few specific cases (source CRS is smooth
over the dateline).
"""
crs = norm_crs_or_error(crs)
if self.crs == crs:
return self
if self.crs is None:
raise ValueError("Cannot project geometries without CRS")
if resolution is not None and math.isfinite(resolution):
geom = self.segmented(resolution)
else:
geom = self
eps = 1e-4
if wrapdateline and crs.geographic:
# TODO: derive precision from resolution by converting to degrees
precision = 0.1
chopped = chop_along_antimeridian(geom, precision)
chopped_lonlat = chopped._to_crs(crs)
return clip_lon180(chopped_lonlat, eps)
return geom._to_crs(crs)
[docs] def geojson(
self,
properties: Optional[Dict[str, Any]] = None,
simplify: float = 0.05,
resolution: Optional[float] = None,
wrapdateline: bool = False,
**props,
) -> Dict[str, Any]:
"""
Render geometry to GeoJSON.
Convert geometry to ``ESPG:4326`` and wrap it in GeoJSON Feature with supplied properties.
:param properties:
Properties to include in the GeoJSON output.
:param simplify:
Tolerance in degrees for simplifying geometry after changing to lon/lat. Larger number
will result in a smaller (fewer points) and hence faster to display, but less precise
geometry. Default is ``0.05`` of a degree. To disable set to ``0``.
:param resolution:
When supplied, extra points will be added to the original geometry such that no segment
is longer than ``resolution`` units. Passed on to
:py:meth:`~odc.geo.geom.Geometry.to_crs`.
:param wrapdateline: Passed on to :py:meth:`~odc.geo.geom.Geometry.to_crs`
:return: GeoJSON Feature dictionary
"""
gg = self.to_crs("epsg:4326", resolution=resolution, wrapdateline=wrapdateline)
if simplify > 0:
gg = gg.simplify(simplify)
if properties is None:
properties = dict(**props)
return {"type": "Feature", "geometry": gg.json, "properties": properties}
def split(self, splitter: "Geometry") -> Iterable["Geometry"]:
"""shapely.ops.split"""
if splitter.crs != self.crs:
raise CRSMismatchError(self.crs, splitter.crs)
for g in ops.split(self.geom, splitter.geom).geoms:
yield Geometry(g, self.crs)
@property
def geoms(self) -> Iterator["Geometry"]:
sub_geoms = getattr(self.geom, "geoms", [])
for geom in sub_geoms:
yield Geometry(geom, self.crs)
def __iter__(self) -> Iterator["Geometry"]:
warnings.warn(
"Iteration interface is deprecated, please use `.geoms`",
category=DeprecationWarning,
)
yield from self.geoms
def __nonzero__(self) -> bool:
return not self.is_empty
def __bool__(self) -> bool:
return not self.is_empty
def __eq__(self, other: Any) -> bool:
return (
hasattr(other, "crs")
and self.crs == other.crs
and hasattr(other, "geom")
and self.geom == other.geom
)
def __str__(self):
return f"Geometry({self.__geo_interface__}, {self.crs!r})"
def __repr__(self):
return f"Geometry({self.geom}, {self.crs})"
# Implement pickle/unpickle
# It does work without these two methods, but gdal/ogr prints 'ERROR 1: Empty geometries cannot be constructed'
# when unpickling, which is quite unpleasant.
def __getstate__(self):
return {"geom": self.json, "crs": self.crs}
def __setstate__(self, state):
self.__init__(**state)
@property
def is_multi(self) -> bool:
"""True for multi-geometry types."""
t = self.type
return t.startswith("Multi") or t == "GeometryCollection"
def __rmul__(self, A: Affine) -> "Geometry":
"""
Map geometry points through linear transform ``A*g``.
"""
return self.transform(A)
def svg_path(self, ndecimal: int = 6) -> str:
"""
Produce SVG path text.
This should work for polygons/rings/lines, doesn't really
makes sense for points.
Example usage: ``f'<path d="{g.svg_path(0)}" ... />'``
"""
def render_ring(g, close):
return (
"M"
+ "L".join(f"{x:.{ndecimal}f},{y:.{ndecimal}f}" for x, y in g.coords)
+ ("z" if close else "")
)
if self.is_multi:
return "".join([g.svg_path(ndecimal) for g in self.geoms])
if self.type == "Polygon":
return "".join(
[render_ring(g, close=True) for g in [self.exterior, *self.interiors]]
)
return render_ring(self, close=self.is_ring)
def filter(self, pred: Callable[[float, float], bool]) -> "Geometry":
"""
Keep only those points for which `pred(x,y) is True`.
"""
if self.type == "Polygon":
# TODO: deal with interior rings
pts = [(x, y) for x, y in self.exterior.points if pred(x, y)]
return polygon(pts, self.crs)
if self.type in ("LinearRing", "LineString"):
pts = [(x, y) for x, y in self.points if pred(x, y)]
_geom = type(self.geom)(pts)
return Geometry(_geom, self.crs)
if self.type == "Point":
x, y = self.coords[0]
if pred(x, y):
return self
return Geometry(geometry.Point(), self.crs)
if self.type == "MultiPoint":
pts = [(x, y) for x, y in [pt.points[0] for pt in self.geoms] if pred(x, y)]
return multipoint(pts, self.crs)
if self.is_multi:
_filtered = [g.filter(pred).geom for g in self.geoms]
_filtered = [g for g in _filtered if not g.is_empty]
_geom = type(self.geom)(_filtered)
return Geometry(_geom, self.crs)
raise AssertionError("Unhandled geometry type detected") # pragma: no cover
def dropna(self) -> "Geometry":
"""
Only keep finite points.
"""
return self.filter(lambda x, y: math.isfinite(x) and math.isfinite(y))
[docs]def common_crs(geoms: Iterable[Geometry]) -> Optional[CRS]:
"""
Compute common CRS.
:return: CRS common across geometries.
:return: ``None`` when input was empty
:raises: :py:class:`odc.geo.crs.CRSMismatchError` when there are multiple.
"""
all_crs = [g.crs for g in geoms]
if len(all_crs) == 0:
return None
ref = all_crs[0]
for crs in all_crs[1:]:
if crs != ref:
raise CRSMismatchError()
return ref
[docs]def projected_lon(
crs: MaybeCRS,
lon: float,
lat: Tuple[float, float] = (-90.0, 90.0),
step: float = 1.0,
) -> Geometry:
"""
Project vertical line along some longitude into a given CRS.
:param crs: Destination CRS
:param lon: Longitude to project
:param lat: Optionally limit range of the line
:param step: Line "resolution" in degrees
"""
crs = norm_crs_or_error(crs)
yy = numpy.arange(lat[0], lat[1], step, dtype="float32")
xx = numpy.full_like(yy, lon)
tr = CRS("EPSG:4326").transformer_to_crs(crs)
xx_, yy_ = tr(xx, yy)
pts = [
(float(x), float(y))
for x, y in zip(xx_, yy_)
if math.isfinite(x) and math.isfinite(y)
]
return line(pts, crs)
[docs]def clip_lon180(geom: Geometry, tol=1e-6) -> Geometry:
"""
Tweak Geometry in the vicinity of longitude discontinuity.
For every point within ``tol`` degress of ``lon=180|-180``, clip to either ``lon=180`` or
``lon=-180``. Which one is decided based on where the majority of other points lie.
.. note::
This will only do the "right thing" for "chopped" geometries. Expectation is that all the
points are to one side of ``lon=180`` line, but some might have moved just beyond due to
numeric tolerance issues.
.. seealso:: :py:meth:`odc.geo.geom.chop_along_antimeridian`
"""
thresh = 180 - tol
def _clip_180(xx, clip):
return [x if abs(x) < thresh else clip for x in xx]
def _pick_clip(xx: List[float]):
cc = 0
for x in xx:
if abs(x) < thresh:
cc += 1 if x > 0 else -1
return 180 if cc >= 0 else -180
def transformer(xx, yy):
clip = _pick_clip(xx)
return _clip_180(xx, clip), yy
if geom.type.startswith("Multi"):
return multigeom(g.transform(transformer) for g in geom.geoms)
return geom.transform(transformer)
[docs]def chop_along_antimeridian(geom: Geometry, precision: float = 0.1) -> Geometry:
"""
Chop a geometry along the antimeridian.
:param geom: Geometry to maybe partition
:param precision: in degrees
:returns: either the same geometry if it doesn't intersect the antimeridian,
or multi-geometry that has been split.
"""
if geom.crs is None:
raise ValueError("Expect geometry with CRS defined")
l180 = projected_lon(geom.crs, 180, step=precision)
if geom.intersects(l180):
return multigeom(geom.split(l180))
return geom
###########################################
# Helper constructor functions a la shapely
###########################################
[docs]def point(x: float, y: float, crs: MaybeCRS) -> Geometry:
"""
Create a 2D Point.
>>> point(10, 10, crs=None)
Geometry(POINT (10 10), None)
"""
return Geometry({"type": "Point", "coordinates": [float(x), float(y)]}, crs=crs)
[docs]def multipoint(coords: CoordList, crs: MaybeCRS) -> Geometry:
"""
Create a 2D MultiPoint Geometry.
>>> multipoint([(10, 10), (20, 20)], None)
Geometry(MULTIPOINT (10 10, 20 20), None)
:param coords: list of x,y coordinate tuples
"""
return Geometry({"type": "MultiPoint", "coordinates": coords}, crs=crs)
[docs]def line(coords: CoordList, crs: MaybeCRS) -> Geometry:
"""
Create a 2D LineString (Connected set of lines).
>>> line([(10, 10), (20, 20), (30, 40)], None)
Geometry(LINESTRING (10 10, 20 20, 30 40), None)
:param coords: list of x,y coordinate tuples
"""
return Geometry({"type": "LineString", "coordinates": coords}, crs=crs)
[docs]def multiline(coords: List[CoordList], crs: MaybeCRS) -> Geometry:
"""
Create a 2D MultiLineString (Multiple disconnected sets of lines).
>>> multiline([[(10, 10), (20, 20), (30, 40)], [(50, 60), (70, 80), (90, 99)]], None)
Geometry(MULTILINESTRING ((10 10, 20 20, 30 40), (50 60, 70 80, 90 99)), None)
:param coords: list of lists of x,y coordinate tuples
"""
return Geometry({"type": "MultiLineString", "coordinates": coords}, crs=crs)
[docs]def polygon(outer, crs: MaybeCRS, *inners) -> Geometry:
"""
Create a 2D Polygon.
>>> polygon([(10, 10), (20, 20), (20, 10), (10, 10)], None)
Geometry(POLYGON ((10 10, 20 20, 20 10, 10 10)), None)
:param coords: list of 2d x,y coordinate tuples
"""
return Geometry({"type": "Polygon", "coordinates": (outer,) + inners}, crs=crs)
[docs]def multipolygon(coords: List[List[CoordList]], crs: MaybeCRS) -> Geometry:
"""
Create a 2D MultiPolygon.
:param coords:
List of polygons. Where each "polygon" is itself a list of "rings". Each "ring" is a list of
``(x, y)`` tuples. First ring is an outer layer of the polygon, the rest, if present, define
holes in the outer layer.
"""
return Geometry({"type": "MultiPolygon", "coordinates": coords}, crs=crs)
[docs]def box(
left: float, bottom: float, right: float, top: float, crs: MaybeCRS
) -> Geometry:
"""
Create a 2D Box (Polygon).
>>> box(10, 10, 20, 20, None)
Geometry(POLYGON ((10 10, 10 20, 20 20, 20 10, 10 10)), None)
"""
points = [
(left, bottom),
(left, top),
(right, top),
(right, bottom),
(left, bottom),
]
return polygon(points, crs=crs)
[docs]def sides(poly: Geometry) -> Iterable[Geometry]:
"""
Returns a sequence of Geometry[Line] objects.
One for each side of the exterior ring of the input polygon.
"""
XY = poly.exterior.points
crs = poly.crs
for p1, p2 in zip(XY[:-1], XY[1:]):
yield line([p1, p2], crs)
[docs]def multigeom(geoms: Iterable[Geometry]) -> Geometry:
"""Construct ``Multi{Polygon|LineString|Point}``."""
geoms = list(geoms) # force into list
src_type = {g.type for g in geoms}
raw_geoms = [g.geom for g in geoms]
crs = common_crs(geoms) # will raise if some differ
if len(src_type) > 1:
return Geometry(geometry.GeometryCollection(raw_geoms), crs)
src_type = src_type.pop()
if src_type == "Polygon":
return Geometry(geometry.MultiPolygon(raw_geoms), crs)
if src_type == "Point":
return Geometry(geometry.MultiPoint(raw_geoms), crs)
if src_type == "LineString":
return Geometry(geometry.MultiLineString(raw_geoms), crs)
raise ValueError("Only understand Polygon|LineString|Point")
###########################################
# Multi-geometry operations
###########################################
[docs]def unary_union(geoms: Iterable[Geometry]) -> Optional[Geometry]:
"""
Compute union of multiple (multi)polygons efficiently.
"""
geoms = list(geoms)
if len(geoms) == 0:
return None
first = geoms[0]
crs = first.crs
for g in geoms[1:]:
if crs != g.crs:
raise CRSMismatchError((crs, g.crs))
return Geometry(ops.unary_union([g.geom for g in geoms]), crs)
[docs]def unary_intersection(geoms: Iterable[Geometry]) -> Geometry:
"""
Compute intersection of multiple (multi)polygons.
"""
return functools.reduce(Geometry.intersection, geoms)
[docs]def intersects(a: Geometry, b: Geometry) -> bool:
"""
Check for intersection.
:return: ``True`` if geometries intersect, else ``False``
"""
return a.intersects(b) and not a.touches(b)
[docs]def bbox_union(bbs: Iterable[BoundingBox]) -> BoundingBox:
"""
Compute union of bounding boxes.
Given a stream of bounding boxes compute enclosing :py:class:`~odc.geo.geom.BoundingBox`.
"""
# pylint: disable=invalid-name
try:
bb, *bbs = bbs
except ValueError:
raise ValueError("Union of empty stream is undefined") from None
L, B, R, T = bb
crs = bb.crs
for bb in bbs:
l, b, r, t = bb
L = min(l, L)
B = min(b, B)
R = max(r, R)
T = max(t, T)
if crs != bb.crs:
raise CRSMismatchError((crs, bb.crs))
return BoundingBox(L, B, R, T, crs)
[docs]def bbox_intersection(bbs: Iterable[BoundingBox]) -> BoundingBox:
"""
Compute intersection of boudning boxes.
Given a stream of bounding boxes compute the overlap :py:class:`~odc.geo.geom.BoundingBox`.
"""
# pylint: disable=invalid-name
try:
bb, *bbs = bbs
except ValueError:
raise ValueError("Intersection of empty stream is undefined") from None
L, B, R, T = bb
crs = bb.crs
for bb in bbs:
l, b, r, t = bb
L = max(l, L)
B = max(b, B)
R = min(r, R)
T = min(t, T)
if crs != bb.crs:
raise CRSMismatchError((crs, bb.crs))
return BoundingBox(L, B, R, T, crs)
[docs]def lonlat_bounds(
geom: Geometry, mode: str = "safe", resolution: Optional[float] = None
) -> BoundingBox:
"""
Return the bounding box of a geometry.
:param geom:
Geometry in any projection
:param mode:
safe|quick
:param resolution:
If supplied will first segmentize input geometry to have no segment longer than
``resolution``, this increases accuracy at the cost of computation
"""
assert mode in ("safe", "quick")
if geom.crs is None:
raise ValueError("lonlat_bounds can only operate on Geometry with CRS defined")
if geom.crs.geographic:
return geom.boundingbox
if resolution is not None and math.isfinite(resolution):
geom = geom.segmented(resolution)
bbox = geom.to_crs("EPSG:4326").boundingbox
xx_range = bbox.range_x
if mode == "safe":
# If range in Longitude is more than 180 then it's probably wrapped
# around 180 (X-360 for X > 180), so we add back 360 but only for X<0
# values. This only works if input geometry doesn't span more than half
# a globe, so we need to check for that too, but this is not yet
# implemented...
if bbox.span_x > 180:
# TODO: check the case when input geometry spans >180 region.
# For now we assume "smaller" geometries not too close
# to poles.
xx_ = [x + 360 if x < 0 else x for x in bbox.range_x]
xx_range_ = min(xx_), max(xx_)
span_x_ = xx_range_[1] - xx_range_[0]
if span_x_ < bbox.span_x:
xx_range = xx_range_
return BoundingBox.from_xy(xx_range, bbox.range_y)
[docs]def mid_longitude(geom: Geometry) -> float:
"""
Compute longitude of the center point of a geometry.
"""
((lon,), _) = geom.centroid.to_crs("epsg:4326").xy
return lon