[OSM-talk] access=destination valid only in one direction

[Bernd Raichle]

On Friday, 10 July 2009 15:03:32 +0100,
Peter Childs <pchilds at bcs.org> writes:
 > 2009/7/10 Stanislav Brabec <utx at penguin.cz>:
 > > Hallo.
 > >
 > > Is there a way how to map a street with access=destination valid just
 > > only for one direction? In the reverse direction it is a standard drive
 > > through street.
 > >
 > > http://www.openstreetmap.org/browse/way/30764132
 > >
 > 
 > The standard way to do this is with a second parallel way tagged
 > accordingly, Like a dual carriageway.

... only if it is a dual carriageway!

If it is a single carriageway without physical divider etc., only
_one_ way is mapped.  In this case I tag a direction depending
attribute with an additional ":forward" resp. ":backward" in the key:

  key:forward=...
  key:backward=...

For example, a way with "maxspeed=100" and "maxspeed:forward=70" is a
street with a speed limit of 100 km/h in one, and 70 km/h in the other
direction.  Forward and backward is given in the direction the way is
drawn, and these tag additions are reversed by newer version of JOSM,
if the way is reversed.

Best wishes,
  -bernd