Mike Harris
> -----Original Message----- > From: Steve Bennett [mailto:stevag...@gmail.com] > Sent: 15 December 2009 02:43 > To: Anthony > Cc: openstreetmap > Subject: Re: [OSM-talk] Ditches > > On Tue, Dec 15, 2009 at 1:31 PM, Anthony <o...@inbox.org> wrote: > > In a park is a ditch. There is a very small bridge going > over the ditch. > > I've tagged the ditch with barrier=ditch. Should the ditch > be layer=-1? > > Even though the park is layer=0? > > Layers are only there to explain the relative heights of > things when they meet. No harm will result from marking the > ditch as layer -1. See my separate reply - I disagree - what happens when the "level=-1" ditch runs downstream into a "level=0" stream / river - without a waterfall? > Whether or not it needs to be a lower number than that of the > bridge is an unresolved question. I disagree - surely the bridge is above the water in the ditch and so - by your own defintion ('relative heights') it must have a higher level value? > > Should I use barrier=entrance on the node where the ways overlap, > > bridge=yes on the bridge (which means splitting the way for a very > > short bridge), both, something else? > > There shouldn't be a junction between the bridge and the > ditch, so no need to mark anything barrier=entrance. Just > mark the whole bridge bridge=yes. Agree - but the way has to be split for the bridge=yes section. > > http://wiki.openstreetmap.org/wiki/Image:IMG_6784.JPG > > http://wiki.openstreetmap.org/wiki/Image:IMG_6783.JPG > > The path: > highway=footway > (possibly bicycle=yes) > > It then meets a bridge: > highway=footway > bridge=yes > layer=1 > > Then another path: > highway=footway > > Meanwhile, unconnected, but crossing the bridge: > waterway=drain > > Not sure I'd even mark it "barrier=ditch" after all that. I'd > also only specify a layer for the bridge, not the ditch/drain. Agree - enough to mark it as a stream or, if that is felt to be too 'big' then waterway=ditch. Also agree that the bridge, rather than the ditch, should carry the layer tag (see my comment above). Doesn't this rather imply that the ditch has the same layer value as the level=0 surroundings (as I suggest) rather than level=-1 (as per your 'no harm' suggestion) - and that the bridge has a layer value higher than 0, so presumably level=1 (as I suggest)? > Steve > > > _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
