This project is an attempt to automatcally generate centerlines for riverbanks that have none in OSM's data. You can read about the rationale behind it here. As per @imagico's idea, one goal for this project is to become a JOSM plugin.
So far the project is divided in two parts. The module itself has just a couple
of dependencies: python3-shapely for the processing and python3-fiona for
writing into a shapefile, and optionaly.python3-psycopg2 for usgin PostGIS
as the source for the skeleton and the medial.
See requirements.txt.
If you have your way, skeleton and medials as shapely.geometry objects, just
call:
import centerlines
c_lines= centerlines.extend_medials (way, skeleton, medials)
This returns the medials extended to the way, in form of a MultiLineString.
If you only have your way, but have a PostgreSQL+PostGIS database you can access, then you can use the helper function:
import psycopg2
c= psycopg2.connect (...)
skeleton, medials= centerlines.skeleton_medials_from_postgis (c, way)
c_lines= centerlines.extend_medials (way, skeleton, medials)