josm plbuildings for Northrhine-Westfalia
For a long time building imports in Northrhine-Westfalia or NRW was a hassle. The only source would be a WMS server and some people wrote software to convert the WMS tiles back to some useful vector informations and merge into the josm dataset. This solution was pretty fragile and my impression is that its basically unmaintained, although it still works for me.
For a long time i was looking for a solution to use something like generic WFS in JOSM with a rule based merging of tags and or geometries (Which geometries to use nodes from, snap distance etc). Nothing like this popped up in the last 10 years.
So i had a look yesterday and found the plbuildings plugin which just needs the right server component to serve OSM XML files.
So i quickly hacked a server component to server the NRW Open Data Shape dataset.
When you install the plbuildings plugin into josm, and change the URL to:
plbuildings.server_url=https://osm.zz.de/plbuildingsnrw/v1/
You will be able to import building outlines from the Hausumringe NRW dataset. I am not that happy with the amount of nodes this dataset contains, or the usability with the plbuildings plugin, but its a start.
Also this will most like break horribly if you have real multipolygon buildings e.g. with a hole in the middle. This is not yet implemented at least on the server side as it would require to serve back a relation. I have no idea whether the plbuildings plugin supports this.