A 3D obelisk like the Washington Monument

I have a question: is it possible to map an obelisk like the Washington Monument (http://en.wikipedia.org/wiki/Washington_Monument)? The higher it gets, the smaller the object becomes. It ends with a pyramidal roof on it. The basic square on the bottom has a side length of 16.8 metres, in 152 metres of height the side length is only 10.50 metres. The following pyramidal roof has an height of 17.3 metres.
How can I enter this datas in OSM so a 3D renderer shows this correctly. Or is it not possible?

Well, there is a man_made=obelisk proposal. I’m not sure if any 3D renderer already supports it.

If we are talking about modelling such a shape using Simple 3D Buildings, this is not yet possible. However, there was a recent thread in the German forum suggesting a building:shape=sphere tag for spherical building parts. Such a tag could perhaps be extended with values for conic and pyramidal shapes, including truncated pyramids as found in obelisks.

I know this example, where somebody used building=yes to tag the shape of the obelisk:

But IMHO this is a cheat and is in conflict with our #1 rule not to tag for renderers :wink:

Yes, in particular I meant the modelling of this conical shape. It does not lool like that this man_made=obelisk has keys for the exact measurements. So it seems there is no actual way to put this measurements in the data. :frowning:

Is a obelisk that you can enter and that has steps and viewpoints not a building?

At this example, it’s only a minor one, that you cant enter: http://de.wikipedia.org/wiki/Siegess%C3%A4ule_%28Schwerin%29