This is the building:
http://www.dagvandearchitectuur.be/2015/website/programma/Vlaams-brabant/watersilo
http://www.hln.be/regio/nieuws-uit-beersel/eerste-watersilo-van-belgie-geopend-a2482766/
The concept is simple enough. 2 triangles, except they are ‘upside-down’. The one at the base is smaller than the roof. The roof is also what I would consider the ‘footprint’, seen from above.
This is the result: http://demo.f4map.com/#lat=50.7517608&lon=4.3268164&zoom=20&camera.theta=41.039&camera.phi=53.858
This the changeset:
http://www.openstreetmap.org/changeset/35781830#map=18/50.75150/4.32780
Is there a way to accomplish this?
Polyglot