On Fri, Oct 14, 2011 at 12:35 PM, Frederik Ramm <frede...@remote.org> wrote: > Hi, > > On 10/14/2011 01:18 PM, John Sturdy wrote: >>> >>> Are you recommending to tag subway stations as buildings in order to be >>> able >>> to tag their entrances? >> >> That seems logical to me. Is there some problem with doing this, that >> I haven't seen? > > Sorry, I forgot that a subway station does not always have to be under > ground. > > Tagging an above-ground subway station as a building is common practice. For > underground buildings, things are more difficult; we don't have an > established way of recording the fact that they are below the surface. > layer=-1 doesn't cut it as it is only relative to other features, not > relative to the surface; and tunnel=yes doesn't sound right either (a subway > station is not a tunnel, and is not usually "in a tunnel" either).
I'd go with Nathan's suggestion of "location=underground" for this one. > For this reason, most renderings will look shite with underground buildings, > and even non-rendering uses will draw the wrong conclusions from a > subterranean subway stations being tagged as buildings. Although perhaps such applications should be written to check the location tag? There are also some "overground" buildings, in which the only part of the building at ground level is a set of pillars, so such applications might have problems with those, too. Alternatively, I suppose we could have "man_made=subway_station" to avoid calling it a building, but I think "made_made=*" seems to be for things less similar to normal buildings than underground stations are. > But then again, the underground buildings are those for which knowing the > location of the entrance is most useful because you cannot simply walk > around them until you find one ;) Now I see what you mean --- I had forgotten that some subway stations are entirely underground rather than having at least a small building on the surface. I think that underground buildings rendering badly is a problem for the renderer authors, and we should stick to the rule "don't tag for the renderer", as it's better for renderers to be re-written to understand location=underground (perhaps as a generic thing for all kinds of feature, maybe setting them to use dashed lines or paler colours). __John _______________________________________________ Tagging mailing list Tagging@openstreetmap.org http://lists.openstreetmap.org/listinfo/tagging