Inconsistent selection of buildings in landuse relations (bug?)

IgorEliezer · February 23, 2023, 2:30pm

My objective: select all buildings within residential landuse ways and relations in a municipality, as follows (query below):

Select municipality by geocodeArea;
Select landuse=residential ways and relations, with note tag;
Show outlines of areas found in the step 2 on map;
Select buildings (ways and relations) within the areas found in the step 2;
Show selected buildings on map.

Results:

The query found successfully all landuse ways and relations as intended.
100% of buildings are found if within ways, but the query skips about 3 out of 4 relations, even if the relation was found. I don’t know why. The relations are closed.

The query: overpass turbo

To help the debugging, the ways are painted blue, and the relations in red.

Any help is appreciated,

Igor

milet · February 23, 2023, 2:54pm

It seems like the skipped relations don’t have a name tag.
Relations where buildings are found, do have a name.

IgorEliezer · February 23, 2023, 3:15pm

It seems you have a point, despite the fact the query doesn’t have any filter about objects having a name or not. If this confirms, I’ll open a bug report on Overpass GitHub.

IlBano · February 23, 2023, 5:11pm

I think @milet is right.
The script that is used for area objects creation has a rule that requires name key presence for multipolygon relations to be considered areas.

IlBano · February 23, 2023, 5:17pm

Found right now that the “issue” was already submitted

github.com/drolbr/Overpass-API

multipolygon invisible

opened 10:09PM - 10 Jan 19 UTC

Mahabarata

question

Hi, first time I write here. I wrote an issue in OSM's github, they told me i…t was a pb of overpass. I copy/paste the isssue I have made over there but I edit it to show you the overpass's pb : I have 2 pbs, one with ID and the other one with OSM (edit : overpass). I open 2 issues, with the same text because my "story" mixes both. I wanted to add a relation to a polygon (in ID) : the relation (multipolygon) is a very big one (scrub) and I'm in the middle, very far from the outer and from any inner. Visible here : https://www.openstreetmap.org/query?lat=-27.70305&lon=-66.00780 1) ID's pb : when I select the polygon and go in its relations' part, the scrub is not listed : when zooming out (losing the possibility to edit the polygon), I found the outer line, found the number of the relation. But when I come back to the polygon (zoom in) and put this number in the relation, nothing happens. How to add a relation if the wanted relation is not listed and you can not add its number ? 2) edit : overpass's pb ? Before to zoom, I opened a new tab (right click on the title "openstreetmap") to be out of ID but in the area of the polygon (see link above). I use the last button on the right (request on the objets) on the scrub. Result : the request don't see the scrub. The request sees the administrative limits and nothing else. But on the map we see only one (or almost) thing : the scrub. Even if I found how to have the number of the scrub (see point 1), I think it should be better that the request find it directly. Best regards

IgorEliezer · February 23, 2023, 7:29pm

Ouch, that is bad. Say I want to find all residential buildings in flood-prone areas, wetlands and the like in a state/province? Many of those areas, due to complicate outline, are traced as multipolygons. It’s not like I should go to every flood-prone area and give them a mock name just to make a query work (of course, I’m not going to do that).

(EDIT: Still I find questionable requiring a name “under the hood” when the statement wr[building](area.aland) says nothing about names. It’s non-intuitive/explicit behavior. It would be clearer if the overpass just threw “The query is too expensive to process”.)

Is there any practical workaround?