[Tagging] new access value

Friedrich Volkmann bsd at volki.at
Sat Oct 10 01:22:20 UTC 2015


On 09.10.2015 23:42, ajt1047 at gmail.com wrote:
>>> localised meaning does not always have to be parsed into universal
>>> tags.
>>>
>>> Here in the UK we have very specific access legislation for paths. On a
>>> bridleway, for example, cycling is permitted, but cycle racing is forbidden,
>>> and cannot be authorised (whereas it can be authorised on other rights of
>>> way). Then we have "restricted byways". And "byways open to all traffic".
>>> And "unclassified county roads". And so on.
>> Sounds more like a road type issue than an access tags issue.
> 
> It's not a road type issue.  It's not especially uncommon to have a "legal
> right of access" that legally allows vehicles that physically won't fit.

This discussion is about access tags, hence legal right of access. In this
context, physical fit does not matter.

>>> So we use the standard OSM broad-brush duck tagging (highway=track,
>>> highway=footway, highway=cycleway etc.) and add a UK-specific value to
>>> record the legal status of the path (designation=public_bridleway,
>>> designation=restricted_byway, designation=byway_open_to_all_traffic etc.).
>>> That way, it's easy to map, easy to parse in outline, possible to parse in
>>> detail, and doesn't impose a burden on the 95% of non-UK mappers or the 99%
>>> of data consumers who don't care.
>> However, the data consumers who do care have a hard time.
> 
> I do care (I create maps that incorporate these rights of way), and don't
> have a hard time.

Are you UK-based by any chance? Of course everyone incorporates the tags
used by the own community.

How do you handle designation=Državna_cesta?

> "creating a proprietary tag" is effectively exactly what you're proposing
> (the first line of the first message in this thread was "I intend to write a
> proposal for a new access=* value, but I don't know a reasonable tag name.").

This tag will not be proprietary. It will have a clearly defined meaning, it
will be documented in the usal wiki pages, and everyone all over the world
is free to use it.

> You're entirely within your rights to use a new "access" value, and everyone
> else (router developers included) is entirely within their rights (and very
> likely) to ignore it.

Application developers in countries where such roads exist will certainly
support the tag right from the start, and others will follow when usage
numbers increase.

Anyway, I don't care whether the tag is supported. I don't do "mapping for
routers". If they want to use it, that's fine. If they ignore it, that's
fine too. Nobody is forced to use their software.

> This does a worse job of communicating the access
> rights to the intended audience than "access=destination with some sort of
> caveat" would.

A proposal (with certainly plenty of discussion) and the subsequent
documentation at key:access will be sufficient communication. We don't need
to visit every developer on Earth personally for every new tag.

> There are routers out there that don't understand that bicycle access on
> trunk roads is country dependant, or that it might be possible to route
> _through_ gates on tracks; do you really think that they'll cope well with
> an access value that they've never heard of?

Yes, because the new value will neither be country-dependent (as bicycle on
trunk) nor lockable (as a gate).

I reckon that most applications will treat the new tag as a synonym for
access=yes or no, just as they do for
access=destination/delivery/agricultural/etc. But applications will
elaborate over the years, and we don't want to remap all data when
applications happen to be ready.

-- 
Friedrich K. Volkmann       http://www.volki.at/
Adr.: Davidgasse 76-80/14/10, 1100 Wien, Austria



More information about the Tagging mailing list