Elena of Valhalla schrieb: > On Sat, Dec 20, 2008 at 1:17 AM, Sven Rautenberg <[email protected]> wrote: >> Please reconsider. >> >> I hate it when I see rivers, streams etc. illogically marked as >> layer=-1. There is no reason to do so, because a river usually is at the >> top of the surface, and that is "no layer" or "layer=0". > > not so true everywhere: in mountain areas rivers are usually at the > bottom of valleys,
The bottom of a valley is layer=0. > and I've seen many small rivers covered and > practically brought underground in urban areas. These streams should be tagged tunnel=yes, layer=-1. > as a guideline, i usually mark the road +1 if it rises to become a > bridge, but 0 and the river -1 if the river is lower than the ground > where most of the road is If you come across an existing stream which has no layer tag, do you add "layer=-1" to the whole stream and then check the whole stream if your change may conflict e.g. with a tunnel which is already at layer=-1? I don't think so. Tagging a part of a way with a non-default layer does not mean anything about it's elevation. It is all relative, but it is a good idea to assume "natural surface level" to be layer=0 in most cases. The stream therefore is the natural surface wherever its water flows. The bridge is above the water, so it is layer=1. And it is less dangerous when just tagging the bridge compared to tagging the whole stream. Regards, Sven _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
