[Tagging] Formally informal sidewalks

marc marc marc_marc_irc at hotmail.com
Fri Jul 14 11:08:42 UTC 2017

Le 14. 07. 17 à 12:20, Svavar Kjarrval a écrit :
> A street with a sidewalk on either side but no marked crossings:
> http://www.openstreetmap.org/#map=17/64.08800/-21.89846
> (Sidenote: If one tries to route from no. 73 to 42,
> GraphHopper suggests a long route while Mapzen assumes the user is
> already on the other side of the street)
It is a fault (and in my opinion a mistake) to tag a sidewalk separated 
from the road where it is not!
there is only one point that the maper create to connect the sidewalk 
and the road https://www.openstreetmap.org/node/2673312760
of course routing can only use this point, luckily !

A sidewalk really isolated from the road (= by a barrier) does not allow 
crossing outside a crossing. This is the current situation of your example.
This is not specific to the sidewalk, the same happens with roads:
If you cut a road with 2 lanes into 2 road without any link between 
them, routing will not allow you to jump from one lane to the other.

> where the footway ends
> prematurely, the routing software doesn't know it may suggest such a
> "jump" onto the street or not,
the end of the footway must be connected to the street if you are 
able/allowed to switch to the street by foot.
If needed, cut the road : one segment with sidewalk=left/righ, second 
segment with sidewalk=no

> I haven't been able to find any tag or method to do it
a road with not-separed sidewalk should be taged as such :-)

> the "common sense approach" would expect.
routing doesn't know "common sense approach" :)
if 2 sidewalk or roads are taged as "separated without any link", 
routing can't guess that a connection exists.


More information about the Tagging mailing list