GLineEnc is a Google Maps Polyline Encoder--it encodes line geometries such that they can be rendered more efficiently in the browser.
The encoding algorithm is described here.
Python 3.8 and up are supported.
GLineEnc can be installed in the usual ways, for example using pip or
poetry:
# using pip
pip install glineenc
# using poetry
poetry add glineencYou can also use pdm or any other package manager or add it to your
install_requires in setup.py (assuming you're using setuptools).
GLineEnc exposes a single API function, encode_pairs. This function
accepts a sequence of latitude/longitude pairs and returns a string
representing the encoded points and another string indicating the
maximum zoom level at which each point should be displayed:
>>> from glineenc import encode_pairs
>>> result = encode_pairs([(38.5, -120.2), (43.252, -126.453)])
>>> result
('_p~iF~ps|U_c_\\fhde@', 'BB')You could JSONify the result like this to pass it to the browser:
>>> import json
>>> json.dumps({'points': result[0], 'levels': result[1]})
'{"points": "_p~iF~ps|U_c_\\\\fhde@", "levels": "BB"}'On the client, you would create a line from this encoded data like so:
new google.maps.Polyline({
path: google.maps.geometry.encoding.decodePath(path)
});