It's obviously not complete. I took 2 locations that I know well (different countries) and the first has relatively realistic looking 3-d building shapes. The other has nothing.
And that it's using a 3rd party engine. Since the OSM data is "open", there's nothing wrong with making use of it.
As heights and number of levels on the building has been a part of the dataset for a while now:
https://wiki.openstreetmap.org/wiki/Key:building:levels
https://wiki.openstreetmap.org/wiki/Key:height
https://blog.mapbox.com/mapping-3d-building-features-in-open...
It's obviously not complete. I took 2 locations that I know well (different countries) and the first has relatively realistic looking 3-d building shapes. The other has nothing.
And that it's using a 3rd party engine. Since the OSM data is "open", there's nothing wrong with making use of it.