incorrect warning "overlapping identical landuse"

[dieterdreist]

I got a warning about "overlapping identical landuse" when actually I had 2 landuse polygons sharing 1 way (via Multipolygon). There is no issue with such mapping, rather people should be encouraged to keep landuse polygons small, because it makes maintenance easier and makes it easier to refine the polygons with additional properties. If we encourage people to merge landuse polygons because they are of the same type and touching, we will loose way history (not really "lost", but becomes unaccessible during regular editing), and make it harder to add more detail (because these polygons will have to be split again).
I agree a real overlap would be a problem, but if they just touch, the warning is misleading and (IMHO) does more harm than good.
Example way 1154264886

[skyper]

I do not get any warning about the way ​osmwww:way/1154264886

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2023-03-13 21:59:27 +0100 (Mon, 13 Mar 2023)
Revision:18690
Build-Date:2023-03-14 02:30:58
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (18690 en) Linux Debian GNU/Linux 11 (bullseye)
Memory Usage: 155 MB / 256 MB (32 MB allocated, but free)
Java version: 17.0.6+10-Debian-1deb11u1, Debian, OpenJDK 64-Bit Server VM
VM arguments: [-Djosm.home=<josm.pref>]

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[dieterdreist]

interesting, neither do I now. I created the ways and the relations and one of the validator warnings on upload was refering to this way, I right clicked "select" and then "3" to zoom to and it was this way that got selected.

[skyper]

I just tried with completely new objects (ways and relations) but still do not get the warning. Next time, please, create the bug report with Help -> Report Bug and attach a small example file. Thanks

Closing the ticket. Feel free to reopen if you have found an example.

[GerdP]

I think this is a problem that was reported before and I also see it from time to time. The problem is caused by java method area.intersect() which sometimes returns non-empty areas for perfectly correct (multi-)polygons because of rounding issues. I fear there's nothing we can do here.

[skyper]

Duplicate of #20054?

[GerdP]

Marked as duplicate of #20054.
Thanks, this ticket was what I head in mind.