rochoa / python-quadkey

native library to manage quadkey in a fast way

This is a small python library to work with quadkeys in a fast way

installing

pip install git+https://github.com/CartoDB/python-quadkey.git

from source

python -m pip install .

how to use it

import quadkey
print(quadkey.lonlat2quadint(-73.969558715820312, 40.757678985595703)
1013670064444553679

Aknowledgments

The fast technique for quadkey encodig/decoding is taken from https://github.com/yinqiwen/geohash-int

Available Methods

Conversion functions:

xy2quadint(x, y)

• Input: (uint32) x, y coordinates based on WebMercator in the range [0,2^31)
• Output: (uint64) quadint value

xy2webmercator(x, y)

• Input: (uint32) x, y coordinates based on WebMercator in the range [0,2^31)
• Output: (double) web mercator coordinates (SRID 3857)

quadint2webmercator(quadint)

• Input: (uint64) quadint value
• Output: (double) web mercator coordinates (SRID 3857)

quadint2xy(quadint)

• Input: (uint64) quadint value
• Output: (uint32) x, y coordinates based on WebMercator in the range [0,2^31)

lonlat2quadint(lon, lat)

• Input: (double) longitude, latitude in WGS84 (SRID 4326) coordinates in degrees
• Output: (uint64) quadint value

lonlat2xy(lon, lat)

• Input: (double) longitude, latitude in WGS84 (SRID 4326) coordinates in degrees
• Output: (uint32) x, y coordinates based on WebMercator in the range [0,2^31)

lonlat2quadintxy(lon, lat)

• Input: (double) longitude, latitude in WGS84 (SRID 4326) coordinates in degrees
• Output: (uint64) quadint value
• Output: (uint32) x, y coordinates based on WebMercator in the range [0,2^31)

webmercator2quadint(x, y)

• Input: (double) web mercator coordinates (SRID 3857)
• Output: (uint64) quadint value

webmercator2xy(x, y)

• Input: (double) web mercator coordinates (SRID 3857)
• Output: (uint32) x, y coordinates based on WebMercator in the range [0,2^31)

Functions to handle tiles (defined by a quadint value and a zoom level)

tile2range(quadint, zoom)

• Input: quadint value and zoom level
• Output: minimum and maximum quadint values

tile2bbox(quadint, zoom)

• Input: quadint value and zoom level
• Output: bounding box defined by minimum longitude, minimum latitude, maximum longitude and maximum latitude (WGS84)

tile2bbox_webmercator(quadint, zoom)

• Input: quadint value and zoom level
• Output: bounding box defined by minimum x, minimum y, maximum x, maximum y (Web Mercator)

tile_center(quadint, zoom)

• Input: quadint value and zoom level
• Output: longitude and latitude of the tile center (WGS84)

tile_center_webmercator(quadint, zoom)

• Input: quadint value and zoom level
• Output: longitude and latitude of the tile center (Webmercator)

tile_children(quadint, zoom)

• Input: quadint value and zoom level
• Output: quadint values of the 4 children of the tile of level zoom+1

tile_mask(zoom)

• Input: zoom level
• Output: quadint mask to select tiles of the level (with bitwise AND)

tile_suffix_mask(zoom)

• Input: zoom level
• Output: quadint mask to select the significant bits from a zoom level (with bitwise AND)

Conversion of tile representation between quadint, zoom and x, y zoom:

xyz2quadint(x, y, zoom)

• Input: x, y, z coordinates of the tile
• Output: quadint value of the tile

tile2xyz(quadint, zoom)

• Input: quadint value and zoom level
• Output: x, y, z of the tile

Obtaning the list of tiles that intersect a web mercator rectangle,

given a maximum tile zoom level.

tiles_intersecting_webmercator_box(max_zoom, xmin, ymin, xmax, ymax)