[OSM-talk] How to tag streets with separte lanes for each direction?

[matthew-osm at newtoncomputing.co.uk]

Hi!

On Tue, Nov 28, 2006 at 12:07:50AM +0100, Michael Strecke wrote:
> Are there some guidelines on how to tag streets with separate lanes for
> each direction?
> 
> Under which circumstances a way has to be created for each direction?
> Or is this limited to dual carriage ways and motor ways? Which one will
> get the (name) tags. Both?

Both, although it depends entirely on the renderer, and if tags like
osmarender:renderName=no are present. I wouldn't put that on dual-carriageways,
though.

> Example:
> http://wiki.openstreetmap.org/index.php/Image:Primary_InCity_TwoLanesEach.jpg

That is a dual-carriageway, so I'd do it as two ways.

Basically, if you can (physically) do a U-turn in the road, then use one way. If
there is some sort of central reservation (barrier / grass / etc) in the middle,
then it is a dual-carriageway, and you should use two ways.

If there are gaps in the central reservation, then do a way between the two
carriageways to indicate where it is.

Thinking about  routing / direction software and what information it needs to
direct people should help, too.

> How far apart must the lanes be in order to count as a separate way?

Doesn't matter - if you can't drive from one side of the road to the other, then
it needs to be two ways.

All IMHO, of course ;-)

HTH,

-- 
Matthew