On Sat, Jun 27, 2015 at 10:40:52AM +0200, Ture Pålsson wrote: > I recently taught my rendering hack about the ’layer’ tag, and immediately > encountered a set of new problems. For example, consider this ditch: > http://www.openstreetmap.org/way/243331898 > <http://www.openstreetmap.org/way/243331898> . It has layer=-1, probably to > indicate that is passes under the road which it crosses. However, it is > entirely covered by a landuse=farmland with no layer tag, which I take to > mean an implicit layer=0. This means that my renderer now renders the > farmland over the ditch, completely hiding the latter. Meanwhile, Mapnik > obviously does what the tagger intended. > > Is this a tagging error, that I should fix by editing the data, or is it > something that my renderer should be able to cope with? >
it is an error and your renderer should be able to cope with it as it is a pretty common error. Simply ignore any layer tags which are not in combination with bridge,tunnel,covered, steps,indoor or similar - the key:layer wikipage has a longer list of combinations that seem legit. Richard _______________________________________________ talk mailing list talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk