Only building:parts are rendered

[maro-21]

I've recently mapped some buildings in 3D but now I can see that they don't render on OSMBuildings:

These small parts are tagged:

building:part=yes
building:levels=1

The whole building is tagged:

building=apartments
building:colour=#FFFDD0
building:levels=3
roof:colour=#E96B39
roof:levels=0.5
roof:material=roof_tiles
roof:shape=gabled

Is my tagging/geometry wrong or is there something wrong with the renderer?

[kekscom]

Could there be a minimal overlap of parts and building? In this case a building is dropped.
In That case a solution would be adding building:part=yes to the main part as well.

[maro-21]

They have common vertices, I connected building:part to the building.
Would it work if I disconnect building:part?

[kekscom]

Could you post the building ID?

[maro-21]

https://www.openstreetmap.org/way/100935969
https://www.openstreetmap.org/way/235436825

[kekscom]

Thank you.
Building parts are not just touching the main part but are contained entirely.
This will trigger removal of a building which is not declared as part itself.
So far behaviour is as expected.

As soon as you tag building:part to the main element as well everything remains visible.

[maro-21]

Is it correct to have building=* and building:part=yes on one feature?
Osmose triggers such tagging as "suspicious tag combination".

[kekscom]

We are not the instance to say something is correct or not. Also suspicious doesn't mean incorrect.
You are looking for a way to solve overlapping geometries. Either

1. ignore the case entirely -> bigger part 'swallows' smaller part
2. CSG operation -> smaller part is automatically cut out from bigger part
3. decouple geometries -> remove overlap
4. tag the dual use feature accordingly -> building + building:part

We're not going to ignore it as in (1) because it is harming major landmarks.
A CSG operation as in (2) is computationally expensive and currently not reasonable to run.
(3) or (4) are on you.

[maro-21]

Ok, so to solve this case I'm going to add a missing part, this big building:part which covers the rest of [building=*] and I will move the 3D tags from building to building:part, I hope it will help.

But before I do that, I have a similar question.
You said that if there is an overlap, the main building is dropped.

building: https://www.openstreetmap.org/way/100934368
building:part: https://www.openstreetmap.org/way/798969316
building:part: https://www.openstreetmap.org/way/100933828

reality:

OSMBuildings: https://osmbuildings.org/?lat=51.09562&lon=16.94045&zoom=20.0&tilt=30

I don't understand why this was rendered in that way.
It looks like this part is rendered, we can't see the roof color, but there is a small edge but covered with something else...

It looks like the builing:parts are redered but they are covered with bare building, without any tags.
What can I do to fix this?

[maro-21]

It works now:
https://osmbuildings.org/?lat=51.09627&lon=16.93672&zoom=19.6&tilt=22
and
https://osmbuildings.org/?lat=51.09563&lon=16.94057&zoom=20.0&tilt=22

I solved it by adding relation=building in the first case
and in the second case marked it as building:part=no.