# This file is part of the Open Data Cube, see https://opendatacube.org for more information
#
# Copyright (c) 2015-2025 ODC Contributors
# SPDX-License-Identifier: Apache-2.0
"""
Geometric operations on GeoBox class
"""
import itertools
import math
from collections.abc import Iterable
from typing import TypeAlias
from affine import Affine
from odc.geo.math import clamp
from . import BoundingBox, GeoBox, Geometry
from .tools import align_up
# pylint: disable=invalid-name
MaybeInt: TypeAlias = int | None
MaybeFloat: TypeAlias = float | None
def flipy(gbox: GeoBox) -> GeoBox:
"""
:returns: GeoBox covering the same region but with Y-axis flipped
"""
H, W = gbox.shape
A = Affine.translation(0, H) * Affine.scale(1, -1)
A = gbox.affine * A
return GeoBox(W, H, A, gbox.crs)
def flipx(gbox: GeoBox) -> GeoBox:
"""
:returns: GeoBox covering the same region but with X-axis flipped
"""
H, W = gbox.shape
A = Affine.translation(W, 0) * Affine.scale(-1, 1)
A = gbox.affine * A
return GeoBox(W, H, A, gbox.crs)
def translate_pix(gbox: GeoBox, tx: float, ty: float) -> GeoBox:
"""
Shift GeoBox in pixel plane.
(0,0) of the new GeoBox will be at the same location as pixel (tx, ty) in the original GeoBox.
"""
H, W = gbox.shape
A = gbox.affine * Affine.translation(tx, ty)
return GeoBox(W, H, A, gbox.crs)
def pad(gbox: GeoBox, padx: int, pady: MaybeInt = None) -> GeoBox:
"""
Expand GeoBox by fixed number of pixels on each side
"""
pady = padx if pady is None else pady
H, W = gbox.shape
A = gbox.affine * Affine.translation(-padx, -pady)
return GeoBox(W + padx * 2, H + pady * 2, A, gbox.crs)
def pad_wh(gbox: GeoBox, alignx: int = 16, aligny: MaybeInt = None) -> GeoBox:
"""
Expand GeoBox such that width and height are multiples of supplied number.
"""
aligny = alignx if aligny is None else aligny
H, W = gbox.shape
return GeoBox(align_up(W, alignx), align_up(H, aligny), gbox.affine, gbox.crs)
def zoom_out(gbox: GeoBox, factor: float) -> GeoBox:
"""
Change the resolution but cover the same region
factor > 1 --> smaller width/height, fewer but bigger pixels
factor < 1 --> bigger width/height, more but smaller pixels
:returns: GeoBox covering the same region but with bigger pixels (i.e. lower resolution)
"""
from math import ceil
H, W = (max(1, ceil(s / factor)) for s in gbox.shape)
A = gbox.affine * Affine.scale(factor, factor)
return GeoBox(W, H, A, gbox.crs)
def zoom_to(gbox: GeoBox, shape: tuple[int, int]) -> GeoBox:
"""
:returns: GeoBox covering the same region but with different number of pixels and therefore resolution.
"""
H, W = gbox.shape
h, w = shape
sx, sy = W / float(w), H / float(h)
A = gbox.affine * Affine.scale(sx, sy)
return GeoBox(w, h, A, gbox.crs)
def rotate(gbox: GeoBox, deg: float) -> GeoBox:
"""
Rotate GeoBox around the center.
It's as if you stick a needle through the center of the GeoBox footprint
and rotate it counter clock wise by supplied number of degrees.
Note that from pixel point of view, the image rotates the other way. If you have
a source image with an arrow pointing right, and you rotate the GeoBox 90 degrees,
in that view arrow should point down (this is assuming usual case of inverted
y-axis)
"""
h, w = gbox.shape
c0 = gbox.transform * (w * 0.5, h * 0.5)
A = Affine.rotation(deg, c0) * gbox.transform
return GeoBox(w, h, A, gbox.crs)
def affine_transform_pix(gbox: GeoBox, transform: Affine) -> GeoBox:
"""
Apply affine transform on pixel side.
X_old_pix = transform * X_new_pix
:param transform: Affine matrix mapping from new pixel coordinate space to pixel coordinate space of input gbox
:returns: GeoBox of the same pixel shape but covering different region, pixels in the output gbox
relate to input geobox via `transform`
"""
H, W = gbox.shape
A = gbox.affine * transform
return GeoBox(W, H, A, gbox.crs)
[docs]
class GeoboxTiles:
"""
Partition a GeoBox into sub geoboxes
Construct from a :class:`~datacube.utils.geometry.GeoBox`.
:param box: the source :class:`~datacube.utils.geometry.GeoBox`
:param tile_shape: Shape of sub-tiles in pixels (rows, cols)
"""
[docs]
def __init__(self, box: GeoBox, tile_shape: tuple[int, int]) -> None:
self._gbox = box
self._tile_shape = tile_shape
self._shape = tuple(
math.ceil(float(N) / n) for N, n in zip(box.shape, tile_shape)
)
self._cache: dict[tuple[int, int], GeoBox] = {}
@property
def base(self) -> GeoBox:
"""
The base GeoBox
"""
return self._gbox
@property
def shape(self):
"""
Number of tiles along each dimension
"""
return self._shape
def _idx_to_slice(self, idx: tuple[int, int]) -> tuple[slice, slice]:
def _slice(i, N, n) -> slice:
_in = i * n
if 0 <= _in < N:
return slice(_in, min(_in + n, N))
else:
raise IndexError("Index ({},{})is out of range".format(*idx))
ir, ic = (
_slice(i, N, n) for i, N, n in zip(idx, self._gbox.shape, self._tile_shape)
)
return ir, ic
[docs]
def chunk_shape(self, idx: tuple[int, int]) -> tuple[int, int]:
"""
Chunk shape for a given chunk index.
:param idx: (row, col) index
:raises: IndexError when index is outside of ``[(0,0) -> .shape)``
:returns: tuple (nrow, ncols) shape of a tile (edge tiles might be smaller)
"""
def _sz(i: int, n: int, tile_sz: int, total_sz: int) -> int:
if 0 <= i < n - 1: # not edge tile
return tile_sz
elif i == n - 1: # edge tile
return total_sz - (i * tile_sz)
else: # out of index case
raise IndexError("Index ({},{}) is out of range".format(*idx))
n1, n2 = map(_sz, idx, self._shape, self._tile_shape, self._gbox.shape)
return n1, n2
def __getitem__(self, idx: tuple[int, int]) -> GeoBox:
"""
Lookup tile by index, index is in matrix access order: (row, col)
:param idx: (row, col) index
:raises: IndexError when index is outside of ``[(0,0) -> .shape)``
:returns: GeoBox of a tile
"""
sub_gbox = self._cache.get(idx, None)
if sub_gbox is not None:
return sub_gbox
roi = self._idx_to_slice(idx)
return self._cache.setdefault(idx, self._gbox[roi])
[docs]
def range_from_bbox(self, bbox: BoundingBox) -> tuple[range, range]:
"""
Compute rows and columns overlapping with a given :class:`~datacube.utils.geometry.BoundingBox`
"""
def clamped_range(v1: float, v2: float, N: int) -> range:
_in = clamp(math.floor(v1), 0, N)
_out = clamp(math.ceil(v2), 0, N)
return range(_in, _out)
sy, sx = self._tile_shape
A = Affine.scale(1.0 / sx, 1.0 / sy) * (~self._gbox.transform)
# A maps from X,Y in meters to chunk index
bbox = bbox.transform(A)
NY, NX = self.shape
xx = clamped_range(bbox.left, bbox.right, NX)
yy = clamped_range(bbox.bottom, bbox.top, NY)
return yy, xx
[docs]
def tiles(self, polygon: Geometry) -> Iterable[tuple[int, int]]:
"""
Return tile indexes overlapping the polygon
"""
if self._gbox.crs is None:
poly = polygon
else:
poly = polygon.to_crs(self._gbox.crs)
yy, xx = self.range_from_bbox(poly.boundingbox)
for idx in itertools.product(yy, xx):
gbox = self[idx]
if gbox.extent.intersects(poly):
yield idx
