[Tagging] Dispute prevention: meaning of lanes tag
Alan_Mintz+OSM at Earthlink.Net
Thu Apr 19 20:33:00 BST 2012
At 2012-04-19 04:38, Martin Vonwald wrote:
>* PSV lanes SHOULD be included (also ). Example: lanes=3 and
>lanes:psv=1 means we have three lanes and one OF THEM is for PSV only.
Same goes for HOV (high-occupancy-vehicles) lanes, unless they are
separately mapped (which is a better solution for routing, given their
>* Turn lanes SHOULD be included (see  and ).
>* The lane count should change, as soon as a) new lane has reached its
>full width or b) a lane starts to disappear (usually a merge with
>another lane) (also ).
Technically, yes, but it doesn't seem practical in developed areas in the
US, which typically change lane configurations at every major intersection
and then change back again. A typical secondary artery might be 2 lanes in
each direction with a raised center island, expanding to 2 lanes in one
direction and, in the other direction, a left-turn "pocket" (in place of
the center island), 2 straight-ahead lanes, and a right-turn "pocket" (in
place of some land or sidewalk on the right side). While these additional
lanes can be added individually or the way broken to tag them, I just don't
see people doing this. It seems like routers could just as easily assume
these types of configuration between various road classes, unless told
otherwise. I would tag such a road as lanes=4 (lanes=5 if the center island
is, instead, a center turn lane).
> - Two-way roads with a specified lane count, but without a specified
>lanes:forward OR lanes:backward and a lane count, that is divisible by
>two, are assumed to have half of the lanes in each direction, e.g.
>lanes=4 means two lanes in each direction if not specified otherwise.
>I will add a recommendation for this situation, to add explicit
If an odd number, assume a center turn lane (e.g. lanes=5 means 2 forward,
2 backward, 1 center).
+1 to the rest.
Alan Mintz <Alan_Mintz+OSM at Earthlink.net>
More information about the Tagging