[Tagging] Zones and defaults [fork from: access in the wiki]

[althio forum]

/ DISCLAIMER /
Starting new thread for side topics from: [Tagging] access in the wiki

Topic:
How to tag ways that are grouped in a "zone".
Sensible default values
Specific default values by country

related tags and concepts:
zone:maxspeed=[country]:[20/30/40/50/...]
zone:traffic=[country]:[urban/rural]
living_street
Tempo-30-Zone
low_emission_zone
limited_traffic_zone
and so on...



/ DISCUSSION /

althio forum <althio.forum at gmail.com>:
>> (1) proposing tagging for zone like ZTL:

Martin Koppenhoefer <dieterdreist at gmail.com> wrote:
> there is actually a proposal for this kind of zone, to be mapped as a
> polygon, useful e.g. for rendering (with name, ref, etc.), but probably not
> very transparent to inherit access-tags to ways from this.

> http://wiki.openstreetmap.org/wiki/Proposed_features/boundary%3Dlimited_traffic_zone

This is not what I am proposing. My tags are for streets highway=*;
not for a polygon. With direct tags and no need for inheritance from
polygon to ways.
Go beyond my summary and see explanations in my post instead:
>> So possible tag for a ZTL in Italy could be:
>> highway=IT:limited_traffic_zone (scheme similar to highway=living_street)
>> OR
>> highway=residential/pedestrian + zone:traffic=IT:limited_traffic_zone
>> (scheme similar to zone:maxspeed=FR:30 or zone:traffic=DE:urban)
As you mentioned these schemes zone:*=[country]:* follow practical
tagging on each street not "zones".
It is not the primary tag, just an additional tag "+ zone:*=*"  and
merely indicates that a particular way belongs to a real-world zone.

> 2014-12-03 6:35 GMT+01:00 Friedrich Volkmann <bsd at volki.at>:
>> highway=ztl
>> or
>> highway=pedestrian+pedestrian=ztl, and some comment [...]
On Wed, Dec 3, 2014 at 12:18 PM, Martin Koppenhoefer
<dieterdreist at gmail.com> wrote:
> [snip... needlessly harsh tone... snip]
> A ZTL is typically defining access restrictions, it has nothing to do with a road class.

Several road classes (from motorway to residential and special road
types like pedestrian, living_street...) could benefit from sensible
defaults. AFAIK some road classes do already imply defaults.
Furthermore these defaults can be country-specific. Access
restrictions could similarly be included as defaults in a road class.
Hence I guess Friedrich's proposal highway=ztl or mine
highway=IT:limited_traffic_zone.


> I wouldn't prefix this with IT because this is not something that gets
> specified or enabled on a national level.
+
> these do have nationwide the same rules and conditions, unlike ZTLs.

Other countries may have similar features and benefit from the same
tagging [limited_traffic_zone], sensible default values could be set
globally and for each country [IT/UK/...:limited_traffic_zone].

> you won't gain anything with this tagging, because every ZTL has its own
> restrictions, times, exceptions, etc.

You could go a long way with the tagging  *=*:limited_traffic_zone and
some default values like:
+ motorcar=private/destination
+ emergency=yes
+ psv=yes
+ disabled=yes

So back to your scheme:
highway=residential
+ motorcar=private
+ motorcar:conditional=yes @ (18:30-07:30)
+ emergency=yes
+ psv=yes
+ disabled=yes

would be reduced in this ideal case to
highway=IT:limited_traffic_zone
+ motorcar:conditional=yes @ (18:30-07:30)
OR
highway=residential
+ zone:traffic=IT:limited_traffic_zone
+ motorcar:conditional=yes @ (18:30-07:30)

Added benefit is that when a contributor is simply tagging
"limited_traffic_zone" we have easily and immediately a lot of
real-case situations correctly handled. And everything can be refined
with further minimal tagging including conditional time and local
exception rules.

/ RANT /
Geez... Martin, it would be better if you reply to the full-extent
discussions and not to the short statements from a summary.