On Wed, Jun 21, 2017 at 05:25:28PM +0200, Maarten Deen wrote: > I don't know if this was an issue with previous renderings too, but what I > also see are multipolygons that do not have a way that is inside it as > member. The inside way still renders but the style of the outer will also > render over the inside way. > Example here: http://www.openstreetmap.org/relation/2456565 where there is a > lake in a woodland area which results in trees in the lake. > > Is it possible to make a maproulette challenge for these cases?
This is a much more difficult issue to detect, because you have to understand the different tags and how they interact. For instance, drawing a building on top of a residential area is okay, you should not cut out a space in the residential area for that building. But you have to cut out a lake from a forest. There is no clear documentation what these interactions are. The other problem is that you need to do a lot of geometry operations to find those overlaps. Not really difficult, but it is more effort than just comparing tags on member ways and relations. I want to do this at some point, but want to focus on the easier cases first. Also see https://github.com/osmlab/fixing-polygons-in-osm/issues/22 Jochen -- Jochen Topf joc...@remote.org https://www.jochentopf.com/ +49-351-31778688 _______________________________________________ talk mailing list talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk