[Tagging] Feature Proposal - Voting - lanes General Extension

Martin Vonwald imagic.osm at gmail.com
Wed Mar 7 08:22:04 GMT 2012


2012/3/7 Tobias Knerr <osm at tobias-knerr.de>:
> Martin Vonwald wrote:
>>> ~ 11.500 cycleway:left/right
>>> ~ 10.000 footway=left/right, 22.000 if you count "both" (same proposal)
>>> ~  4.500 footway:left/right/both:*
>> As far as I understand, those are ways next to the carriageway.
> If they are mapped as tags on the highway=* way, rather than as separate
> ways, then they are part of the highway=* as far as OSM is concerned.
> I don't think it matters whether they are part of the carriageway. Some of
> them are (cycle lanes that have no physical barrier to or are even
> surrounded by car lanes), others - such as cycleway:*=track - are not.

Let's take again a look at the usage of :right/:left tags according to taginfo.
The #1 ending on :right (only right) is name:right and is used 27.000
times. If we now sum up the count for cycleway:left, cycleway:right,
cycleway:both, footway:right:*, footway:left:* and footway:both:* we
get approx. 17.000 .
Yes, that's a lot. And yes, that is far less, than the #1 using only
for :right. And name:right is clearly something "next to" the
carriageway.


>>> My suggestion for separating the approaches is:
>>> * Physical placement of things relative to road centerline: left/right.
>>> * Legal restrictions depending on driving direction: forward/backward.
> ................................
> A maxspeed:lanes:* is, according to my mental model, a legal restriction
> that applies to a physical part of the road. It is not driving
> direction-dependent as such.

So you want all legal restrictions depending on driving direction
using forward/backward, but not legal restriction, that applies to a
physical part? It's getting a little tricky here ;-)
BTW: maxspeed is not direction-dependent?
Furthermore: are you suggesting to replace all
maxspeed:forward/backward by maxspeed:left/:right? Yes? I'm pretty
sure, this wont happen. No? So we should have
maxspeed:forward/backward AND maxspeed:left/right?

>> In case of mixed lanes this would be tagged like this:
>> http://wiki.openstreetmap.org/wiki/Proposed_features/lanes_General_Extension/ProposalPreVoting#Difficult_lane_layout
> So I could do something like
>  direction:lanes:forward = forward|backward|both_ways|forward
> ? I think it would make your proposal less problematic if something like
> that was at least possible.
> To put this differently: Can you guarantee me that, in a right-hand driving
> country, all lanes:forward will always be to the right of all lanes:backward
> of the same road?

No, I can not. That's why I suggested the direction key. In the case
lanes use mixed direction, you could(!) either 1) split the way or 2)
use the direction key.
An example:
  highway=residential
  lanes=3
  railway:lanes=|tram|tram
  direction:lanes=backward|backward|forward
  direction:tram:lanes=|both_ways|both_ways|
We got here a residential street, with three lanes. On two lanes tram
tracks are present. The general direction of the lanes is backward,
backward and forward (as viewed from the direction of the osm-way,
left to right), the tram-specific direction is none (not a tram
track), both ways and both ways.

Note: as long as editors don't support the direction:lanes tag, I
strongly recommend using direction:lanes:forward instead, otherwise
the direction information would be destroyed, it the way is reversed.
This is pretty ugly, but works and is only needed until editors know,
that they need to reverse the lane-values in the direction key.

Martin



More information about the Tagging mailing list