Source code for rastervision.core.data.crs_transformer.crs_transformer

from abc import ABC, abstractmethod
from typing import TYPE_CHECKING, Any, Optional, overload, Tuple

from shapely.ops import transform
from shapely.geometry.base import BaseGeometry

from rastervision.core.box import Box

if TYPE_CHECKING:
    import numpy as np


class CRSTransformer(ABC):
    """Transforms map points in some CRS into pixel coordinates.

    Each transformer is associated with a particular :class:`.RasterSource`.
    """

    def __init__(self,
                 transform: Optional[Any] = None,
                 image_crs: Optional[str] = None,
                 map_crs: Optional[str] = None):
        self.transform = transform
        self.image_crs = image_crs
        self.map_crs = map_crs

    @overload
    def map_to_pixel(self,
                     inp: Tuple[float, float],
                     bbox: Optional[Box] = None) -> Tuple[int, int]:
        ...

    @overload
    def map_to_pixel(self,
                     inp: Tuple['np.array', 'np.array'],
                     bbox: Optional[Box] = None
                     ) -> Tuple['np.array', 'np.array']:
        ...

    @overload
    def map_to_pixel(self, inp: Box, bbox: Optional[Box] = None) -> Box:
        ...

    @overload
    def map_to_pixel(self, inp: BaseGeometry,
                     bbox: Optional[Box] = None) -> BaseGeometry:
        ...

    def map_to_pixel(self, inp, bbox: Optional[Box] = None):
        """Transform input from map to pixel coords.

        Args:
            inp: (x, y) tuple or Box or shapely geometry in map coordinates.
                If tuple, x and y can be single values or array-like.
            bbox: If the extent of the associated RasterSource is constrained
                via a bbox, it can be passed here to get an output Box that is
                compatible with the RasterSource's get_chip(). In other words,
                the output Box will be in coordinates of the bbox rather than
                the full extent of the data source of the RasterSource. Only
                supported if ``inp`` is a :class:`.Box`. Defaults to None.

        Returns:
            Coordinate-transformed input in the same format.
        """
        if bbox is not None and not isinstance(inp, Box):
            raise NotImplementedError(
                'bbox is only supported if inp is a Box.')
        if isinstance(inp, Box):
            box_in = inp
            ymin, xmin, ymax, xmax = box_in
            xmin_tf, ymin_tf = self._map_to_pixel((xmin, ymin))
            xmax_tf, ymax_tf = self._map_to_pixel((xmax, ymax))
            box_out = Box(ymin_tf, xmin_tf, ymax_tf, xmax_tf)
            if bbox is not None:
                box_out = box_out.to_local_coords(bbox)
            return box_out
        elif isinstance(inp, BaseGeometry):
            geom_in = inp
            geom_out = transform(
                lambda x, y, z=None: self._map_to_pixel((x, y)), geom_in)
            return geom_out
        elif len(inp) == 2:
            return self._map_to_pixel(inp)
        else:
            raise TypeError(
                'Input must be 2-tuple or Box or shapely geometry.')

    @overload
    def pixel_to_map(self,
                     inp: Tuple[float, float],
                     bbox: Optional[Box] = None) -> Tuple[float, float]:
        ...

    @overload
    def pixel_to_map(self,
                     inp: Tuple['np.array', 'np.array'],
                     bbox: Optional[Box] = None
                     ) -> Tuple['np.array', 'np.array']:
        ...

    @overload
    def pixel_to_map(self, inp: Box, bbox: Optional[Box] = None) -> Box:
        ...

    @overload
    def pixel_to_map(self, inp: BaseGeometry,
                     bbox: Optional[Box] = None) -> BaseGeometry:
        ...

    def pixel_to_map(self, inp, bbox: Optional[Box] = None):
        """Transform input from pixel to map coords.

        Args:
            inp: (x, y) tuple or Box or shapely geometry in pixel coordinates.
                If tuple, x and y can be single values or array-like.
            bbox: If the extent of the associated RasterSource is constrained
                via a bbox, it can be passed here so that the box is
                interpreted to be in coordinates of the bbox rather than the
                full extent of the data source of the RasterSource. Only
                supported if ``inp`` is a :class:`.Box`. Defaults to None.

        Returns:
            Coordinate-transformed input in the same format.
        """
        if bbox is not None and not isinstance(inp, Box):
            raise NotImplementedError(
                'bbox is only supported if inp is a Box.')
        if isinstance(inp, Box):
            box_in = inp
            if bbox is not None:
                box_in = box_in.to_global_coords(bbox)
            ymin, xmin, ymax, xmax = box_in
            xmin_tf, ymin_tf = self._pixel_to_map((xmin, ymin))
            xmax_tf, ymax_tf = self._pixel_to_map((xmax, ymax))
            box_out = Box(ymin_tf, xmin_tf, ymax_tf, xmax_tf)
            return box_out
        elif isinstance(inp, BaseGeometry):
            geom_in = inp
            geom_out = transform(
                lambda x, y, z=None: self._pixel_to_map((x, y)), geom_in)
            return geom_out
        elif len(inp) == 2:
            return self._pixel_to_map(inp)
        else:
            raise TypeError(
                'Input must be 2-tuple or Box or shapely geometry.')

    @abstractmethod
    def _map_to_pixel(self, point: Tuple[float, float]) -> Tuple[int, int]:
        """Transform point from map to pixel coordinates.

        Args:
            map_point: (x, y) tuple in map coordinates (eg. lon/lat). x and y
            can be single values or array-like.

        Returns:
            Tuple[int, int]: (x, y) tuple in pixel coordinates.
        """
        pass

    @abstractmethod
    def _pixel_to_map(self, point: Tuple[float, float]) -> Tuple[float, float]:
        """Transform point from pixel to map coordinates.

        Args:
            pixel_point: (x, y) tuple in pixel coordinates. x and y can be
            single values or array-like.

        Returns:
            Tuple[float, float]: (x, y) tuple in map coordinates (eg. lon/lat).
        """
        pass