I’m thinking about special tags for leaning towers
tagging could be :
leaning:tilt : in degrees (default) or meters
leaning:azimuth : in degrees from north, or simply an orientation (NW, SSE)
leaning=shearing when the tilt maintain horizontal plane
some examples :
there are some building with both leaning but i’m not yet sure how to handle those, ideas are welcome !
What do you think ?
That’s an interesting topic, and I’ve been thinking about similar (but slightly different) cases recently. Specifically, there is often the situation that some faces of a building, rather than the entire building, are inclined. From my (limited) personal experience, I would even consider such per-face inclines more common than an entire leaning tower.
Therefore, I’m wondering if we can find an approach that covers both cases.
Per-face inclines can be covered with leaning building:parts I think
What’s about tagging the opposite of an roof.
It could be tagged similar to
This tower could be tagged with three vertical “building:parts”.
It would also be helpful for other shapes like “round” or “dome” (http://de.wikipedia.org/wiki/Atomium) or one-sided leaning.
If we find a solution, maybe I would create this: http://de.wikipedia.org/wiki/Jefferson_National_Expansion_Memorial
yep per face incline would be nice, for building like :
but it’s quite hard to define which face is leaning
it can indeed be done using building:parts but it’s quite hard to get right, and it’s more of a workaround than a solution
An other idea:
We could add
Pre defined is the start point 0;0 on ground or bottom of building:part (height=0 or min_height=z[ground]). The coordinate x;y plus building:height (as z[top]) defines the axis as line.
It also works with pyramidal shapes or asymmetric gabled roofs (roof:axis=x;y) (https://www.schwoererhaus.de/de/haeuser/searchhouse/166)
Indeed: building:part is a workaround, but we talk about Simple 3D. Simple is: less rules and less basic types
You do not need: leaning=shearing
If the roof is horizontal than you can use roof:shape flat, else use roof:shape=skillion…
axis looks really hard to get, using an additional point as axis may be more user friendly imho
however a point as axis won’t help for roofs on complex forms.
if you have a tower with a flat roof, but the whole tower is leaning, if you can’t specify shearing, you won’t be able to map it.
maybe also include a way to indicate a part is bigger at the top than at the bottom on all sides
(like the top of chichen itza : http://demo.f4map.com/#lat=20.6831797&lon=-88.5687217&zoom=21&camera.theta=61.665&camera.phi=35.809 )
for example :
we may even be able to use this with an angle to indicate a side of the building is leaning, what do you think ? (not very straightforward though)
I have another idea that might be useful. But I need to describe some context first:
To tackle the problem that sometimes part of a building’s walls can have a different colour, material etc. than the rest, I’ve thought about proposing a building:wall=yes tag. It would allow you to draw a way on a part of the building outline and add tags like building:colour etc. to it.
It’s loosely based on an idea I discussed with Kendzi in the past. The idea was well received in the German community. I’ve also created a quick test how this could be implemented in OSM2World, perhaps this clarifies what I’m talking about:
So what does that have to do with leaning towers? I was thinking that, maybe, we could add angles to the building wall ways. This would allow different leanings per wall, plus buildings that get wider or narrower towards the top.