[Tagging] Clarify tag access doc

[Martin Koppenhoefer]

2012/9/11 Pieren <pieren3 at gmail.com>:
> On Tue, Sep 11, 2012 at 3:42 PM, Martin Koppenhöfer
> <dieterdreist at gmail.com> wrote:
>> IIRR those were initially intended to mean the same.
> but do you agree with the current definition ?

[1] http://wiki.openstreetmap.org/wiki/Tag:access%3Ddesignated
[2] http://wiki.openstreetmap.org/wiki/Tag:access%3Dofficial

to me [2] seems unambigous and clear. The definition has never changed
and there is only one author, so I don't think that there is need for
changes on this page.

The only problem I think could be there is what is said about Germany
("compulsory") I suspect it is not completely true the way it is
written in [2] (I am only aware about bicycle tracks, bridleways and
sidewalks being compulsory _under certain circumstances_, not in all
cases).


In [1] the first paragraph is a link to a UK-specific page (usually
country specific stuff is not in the beginning of the pages) and there
is still a lot of UK-examples on the general page [1] as well.

Definitions and rules are set in [1] as if they would make sense in a
general way, but actually they mostly deal with exceptions, e.g. this:
"To indicate an exclusive access use access=official, or just use
access=no in addition to a mode-specific key (foot=designated,
bicycle=designated, etc.)"  The first does not make sense on roads or
paths IMHO, only on footway, cycleway and bridleway  (highways
designed for a specific means of transport).


>> Strange tagging. Access=designated does not follow the convention <mode of transport>=designated. You cannot infer access restrictions for cars from this (I.e. fall back to the default, which depends on the highway class).
> But the wiki says "The values can be used with the access tag or with
> tags associated with particular forms of transport.". If you say that
> some values are not going to be used with the general "access" key,
> then we have to document it (currently, taginfo reports 21000
> access=designated).


According to taginfo 10% of these 21000 aren't even highways. I don't
think this is a particularly lucky choice of tagging, as a meaning
only emerges together with other tags (mostly the highway-class), but
in the case of a mode-specific highway-class it does make sense. On
general roads it doesn't. This also becomes clear from the first
sentence: "This tag indicates that a route has been specially
designated (typically by a government) for use by a particular mode
(or modes) of transport."[1]
You could still express the same with foot=designated (for instance)
which I'd prefer over highway=footway, access=designated.


cheers,
Martin