GLineEnc

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.

Supported Python Versions

Python 3.8 and up are supported.

Installation

GLineEnc can be installed in the usual ways, for example using pip or poetry:

# using pip
pip install glineenc

# using poetry
poetry add glineenc

You can also use pdm or any other package manager or add it to your install_requires in setup.py (assuming you're using setuptools).

Usage

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)
});

Google Maps API reference