Some buildings I mapped with the building:part tags are redered weirdly on the Positron map style. As this appears to me to be a common map style, I assume that I missed something during my edits.
You can find examaples here:
It is for example about the katholic church and the corresponding kindergarten-building:
or the town hall
which i find especially impractical as the town uses this map style for the official map on their website, and the map focuses on the town hall when opening.
Could I please get feedback whether this rendering is due to my wrong mapping? And if yes, why?
I had a look at this in my local area, and indeed I can see that Positron (at least in the version available as a background in uMap) seems to render building:part unpredictably, with some building parts appearing as transparent. I couldn’t find any pattern to this - some complex buildings display just fine while simpler buildings have rendering issues.
The only hint of a pattern I could see is that the “transparent” parts have same number of levels as the main building, so that only lower parts of the building get rendered. But that could be just the examples I checked. I can’t think of any reason to render in this way.
The Malaga ferry terminal building, for example, mostly has 3 levels - and that part is transparent. Only a couple of small lower parts are filled in.
I checked that all the “problem” buildings display as expected in the 3D rendering on CoMaps on my phone.
So I don’t think this is due to your wrong mapping - or at least if it is, it’s a problem shared by other mappers with no connection to you. It seems more likely to be an issue with Positron.
Thank you, Alan, for checking. Sorry for answering that late.
Unfortunately, I found a counterexample for your idea.
I found a building, where the building:part=yes is the only property mapped on the buildings. Basically, the same situation as for the townhall in Kleinostheim.
But the building in Mainz is rendered properly (and has not been touched for longer than the edits I made). I added this building to the umap (one needs to zoom out a bit to see it).
I also found a “simple” detached house,
Where I am really confused (see also in the umap). Again, the only tag on the “inner” is building:part=yes.
I am really wondering what is the relevant difference between those buildings I made vs. the ones I found.
I found the same issue with the “Rathhaus Kleinostheim” and the “61 Mittlere Bleiche” building: There are gaps or overlaps in the building:part sections, therefore the normal building-outline is not completely filled. Node: 263666330 | OpenStreetMap is not connected to the building:partWay: 1301426812 | OpenStreetMap , creating a gap
Thank you very much for pointing this out. I fixed the one for Rathaus Kleinostheim.
The buildings in Mainz I mentioned as a counterexample. Maybe this was not clear enough. They render as I would expect. On the other hand, I checked the protestant church in Kleinostheim (one of the affected buildings) and there I was unable to find such a mistake. All the points are well connected.
I am already very curious on what will happen to the townhall (Rathaus) when it will be rendered again.
St. Laurentius has a node on the building outline that is not connected to any building:part as well: Node: 12618340501 | OpenStreetMap
I only noticed this while checking the builings you mentioned, but in the iD Editor, nodes that are only part of one way are white, and nodes that are glued to at least one other way are grey. So all I had to do to was selecting the building outline and the building parts one after the other and see if any one node is white.
Maybe the rendering is affected by building:part overlapping as in the townhall, and/or the building being not completely filled out as in the church and government building.
Edit: I also checked the Kindergarten, but that one doesn’t have any loose nodes.
