WanMil schrieb am 24.09.2010 19:29:
My understanding of the multipolygons is, that the tags may EITHER be in the relation OR on the outer polygons. So the outerpoylgons are only to be used, when there are no tags on the relation. If the relation itself is tagged and there is a tag on the outerpolygons, this does logical mean, that the outerpolygon tags apply to the complete area including the inner-area.
You càn check yourself if it's now the time to remove this polygon list. I have attached a patch that follows your proposal. Just test it and let us know.
I tried your patch today, and I think it looks quite promising. Implementing such a strict scheme will certainly show some faulty multipolygon (e.g. Aussenalster in Hamburg), but perhaps this will encourage a cleaner tagging of such relations. I think the patch has still one problem: If the tags of the outerpolygon are not used for the multipolygon area, they must still be used as a stand-alone polygon. As an example take a nature reserve consisting of a wood with a lake inside. This migth be mapped with two polygons and a relation: polygon A: leisure=nature_reserve (the complete area) polygon B: natural=water (only the inner area) multipolygon relation: natural=wood and outer=polygon A and inner=polygon B (only the surrounding area) Right now polygon A seems to be missing in the resulting map. Gruss Torsten