Function zxy_to_tileid

python/pmtiles/pmtiles/tile.py:46–61

(z: int, x: int, y: int)

def zxy_to_tileid(z: int, x: int, y: int) -> int:
    if z > 31:
        raise OverflowError("tile zoom exceeds 64-bit limit")
    if x > (1 << z) - 1 or y > (1 << z) - 1:
        raise ValueError("tile x/y outside zoom level bounds")

    acc = ((1 << (z * 2)) - 1) // 3
    a = z - 1
    while a >= 0:
        s = 1 << a
        rx = s & x
        ry = s & y
        acc += ((3 * rx) ^ ry) << a
        (x, y) = rotate(s, x, y, rx, ry)
        a -= 1
    return acc


def tileid_to_zxy(tile_id: int) -> tuple[int, int, int]: