[Talk-us] Relation member order/structure; best effort worth it?

Paul Johnson baloo at ursamundi.org
Mon Jan 13 16:05:08 UTC 2014

On Sun, Jan 12, 2014 at 7:18 AM, Peter Davies <peter.davies at crc-corp.com>wrote:

> We would post the cardinal directions using tags for each whole
> directional relation. However where the Muskogee Turnpike turns from E-W to
> S-N, or has some even more complex deal such as E +ve and N -ve, the
> 3-relation method will fail. We could further extend it by breaking the
> relations at the turns (strictly, at the directional posting changes),
> having maybe nine relations for a complete rectangular beltway (2 on each
> of the N, S, W, and E sides, plus a parent) but Martijn and Kristen Kam
> have wanted to avoid relation proliferation. This is why Martijn's firm
> (and OSM mappers) have adopted a hybrid system, as I understand it, using
> posted directions on roles for complex routes, and posted directions on
> directional relations for simple Interstates like I 5.

What's wrong with having one relation per direction with the super relation
acting as a binder clip?  I'm not understanding how this fails.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk-us/attachments/20140113/a01cf156/attachment.html>

More information about the Talk-us mailing list