2009/8/3 Roy Wallace <[email protected]>: > On Mon, Aug 3, 2009 at 9:39 AM, Martin > Koppenhoefer<[email protected]> wrote: >>> Tag the width of the surface on which users of the way are expected to >>> travel. >> I agree and would like to add: "and that is not constricted in the >> full usable height" > > I think the maxheight tag should be used here.
no. I tried to explain, but I was aware that it might be not understandable. I am not talking about height. It's about width. But the width is only then available, if there are no obstacles above. In your definition you were defining the width by the width of the "surface on which users of the way are expected to travel.". This should include that above this surface (I would suggest up to 4,4 meters or up to maxheight where available) there are no obstacles, because otherwise literally it is not complete. The technical correct term in German is "Lichtraumbreite" (my dictionaries don't know it in English, maybe someone else here can help us). > There is no need to > complicate the definition of width. If there is a large obstacle, then > the width under that obstacle would not be included if and only if > "users of the way are NOT expected to travel" under that obstacle. it's IMHO not about complication but about completeness. And it doesn't matter if the obstacle is large or small, it matters if is removable or not. >> well, why not outside the lines? If you really have to know the width >> of the road (transport or similar, or you want to calculate the sealed >> area), you won't care about lines. > > Because users are not expected to travel outside the lines. It also > removes the need to consider the quality of the road outside the > lines, e.g. if there's gravel next to a paved road, does that count? well, it might be interesting to know under certain conditions about this as well, but I agree that this gravel should be put into other tags (e.g. "shoulder", "shoulder:width", "shoulder:surface"). But why not put the width from line to shoulder, still paved, into the width-tag? You are not expected to use this, but you can do. > What about a drop-off? etc., etc. The lines are there for a reason, > and that is to mark the width of the road that is designated as > suitable for driving on. I think that's the most suitable width to > tag. actually I would consider the lines part of the lanes, not of the road. So I would see the width between the inner border of the lines as lanes:width (gets more complicated with different widths of the lanes, but this is a general problem in OSM: currently can't model lanes as they are). This results in a hierarchical model: 1. entire road-construction, consisting of 2. paved road, shoulders, beam barrier, separators, bed, .... 3. the paved roads furthermore consistentent of different lanes where each level can have it's own tags for e.g. width, surface, maxspeed, maxheight, maxweight, access restrictions, etc. which would be inherited to the sublevels if there was not the same tag overriding it. cheers, Martin _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
