sky_starearth_tiler/src/starearth/bound.py

# 一个简单的二维向量 Vector2

class V2:

    def __init__(self, x, y):

        self.x = x
        self.y = y

        pass

    pass


# 一个简单的范围碰撞计算类

class R2:

    def __init__(self, minimum, maximum):

        self._data = (minimum, maximum)

        pass

    @property
    def min(self): return self._data[0]

    @property
    def max(self): return self._data[1]

    @property
    def length(self): return self._data[1] - self._data[0]

    def intersect(self, other):

        if self.min > other.max or self.max < other.min:

            return None

        minimum = self.min if self.min > other.min else other.min
        maximum = self.max if self.max < other.max else other.max

        return R2(minimum, maximum)

    pass


class Bound:

    class CartesianLH:

        @staticmethod
        def top   (r): return r.min

        @staticmethod
        def bottom(r): return r.max

        pass

    class CartesianRH:

        @staticmethod
        def top   (r): return r.max

        @staticmethod
        def bottom(r): return r.min

        pass

    def __init__(self, x_min, x_max, y_min, y_max, cartesian):

        self._rx = R2(x_min, x_max)
        self._ry = R2(y_min, y_max)

        self._cartesian = cartesian

        pass

    @property
    def left  (self): return self._rx.min

    @property
    def right (self): return self._rx.max

    @property
    def top   (self): return self._cartesian.top   (self._ry)

    @property
    def bottom(self): return self._cartesian.bottom(self._ry)

    @property
    def west (self): return self.left

    @property
    def east (self): return self.right

    @property
    def north(self): return self.top

    @property
    def south(self): return self.bottom

    @property
    def x(self): return self._rx.min

    @property
    def y(self): return self._ry.min

    @property
    def width (self): return self._rx.length

    @property
    def height(self): return self._ry.length

    @property
    def value(self):

        return self.west, self.south, self.east, self.north

    @property
    def coordinates(self):

        return \
            [
                [self.west, self.south],
                [self.east, self.south],
                [self.east, self.north],
                [self.west, self.north],
                [self.west, self.south]
            ]

    def intersect(self, other):

        other: Bound = other

        ix = self._rx.intersect(other._rx)
        iy = self._ry.intersect(other._ry)

        if ix is None or iy is None:

            return None

        return Bound(ix.min, ix.max, iy.min, iy.max, self._cartesian)

    @staticmethod
    def LH(left, top, right, bottom):

        return Bound(left, right, top, bottom, Bound.CartesianLH)

    @staticmethod
    def RH(left, bottom, right, top):

        return Bound(left, right, bottom, top, Bound.CartesianRH)

    @staticmethod
    def LH_XYWH(x, y, width, height):

        return Bound.LH(x, y, x + width, y + height)

    @staticmethod
    def RH_XYWH(x, y, width, height):

        return Bound.RH(x, y, x + width, y + height)

    @staticmethod
    def from_transform(width: int, height: int, transform):

        """
        使用从 GDAL 中获取的信息构造边界对象

        :param width:     图像宽度
        :param height:    图像高度
        :param transform: 空间变换数据
        :return:          边界对象
        """

        rx = transform[1]
        ry = transform[5]

        west  = transform[0]
        north = transform[3]
        east  = west  + width  * rx
        south = north + height * ry

        return Bound.RH(west, south, east, north)

    pass