Try to see it from a data consumer point of view. Let's say you are a bicycle routing engine and want to know if you are allowed to drive here. With the current scheme you see an access = no. so you assume you don't have access. Then you look if there are special permissions for bikes (because, after all, you are a bike routing engine) and find nothing like bicycle=yes. So you know what to do: deny access.
With you proposal, you'll find no access = no (just a valid highway tag). So you assume you are allowed there. There is no other key for bikes. So how do you know bikes are not allowed? You'll have to check every possible transportation mode, if maybe one of them has EXCLUSIVE access to this stretch of road. Maybe psv? Maybe hasmat? Who knows.. If you group this under a general key like exclusive_access= psv, you'll at least have a chance (if something is listed, but it's not bike, then deny access). But you'll have to look for it for every d*** road there is, not just those with access = no. So in my opinion, there is no way around first specifying the general case (access = no) and then the special case (psv=yes). Regards, Chaos 2012/10/29 Martin Vonwald <imagic....@gmail.com>: > Hi! > > I'm looking for a possibility to tag "exclusive" access rights. What I > mean by this is a way to specify that one specific vehicle is allowed > and everything else is forbidden. If I specify e.g. hgv=yes it only > means (at least in my understanding) that hgv are allowed there. I'm > not sure about the meaning of access=hgv: is this a valid tag? What is > its meaning? > > I am aware of the combination access=no and xxx=yes, but I'm looking > for a "nicer" solution. The background of my question is the following > demand: specify that the rightmost lane (of three lanes) can only be > accessed by psv and hgv. > Right now I only know this solution: > vehicle:lanes=yes|yes|no > psv:lanes=yes|yes|yes > hgv:lanes=yes|yes|yes > > Three tags for such a simple thing. What I'm looking for is something like > this: > <somenicekey>:lanes=vehicle|vehicle|psv;hgv > > If access=hgv means that only hgv are allowed, I could use that. But > as I wrote: I'm not sure if this tag is valid and if it is I am not > sure about its meaning. > > Any hints/comments/recommendations? > > Martin > > _______________________________________________ > Tagging mailing list > Tagging@openstreetmap.org > http://lists.openstreetmap.org/listinfo/tagging _______________________________________________ Tagging mailing list Tagging@openstreetmap.org http://lists.openstreetmap.org/listinfo/tagging