[OSM-talk] relations in order not to fragment roads (was: correctly mapping avenues)

Frederik Ramm frederik at remote.org
Mon Feb 11 20:49:10 GMT 2008


Hi,

> If we add a thing like segment relations as is proposed, we'll 
> effectively end up with another level next to points, segments and 
> relations (since things like route relations will again have these 
> segment relations contained in them), which will likely increase 
> complexity a lot in my eyes.

Has anyone actually proposed such a thing? That would indeed be
unnecessarily complex.

As far as I understand it, the idea is simply to qualify a tag with
start and end node. I.e. you have a way that goes from node A, B, C to
Z, but from B to D and from M to P it is a pedestrian road. So,

old scheme:

split way into 5 parts (3 non-pedestrian, 2 pedestrian) and tag
accordingly.

scheme with "superway" relation:

split way into 5 parts and create one relation to contain them all;
add all common tags to relation; add pedestrian tag to 2 ways.

scheme with "qualified tag" relations:

do not split way. create two relations that each contain the way, plus
the start and end node (B/D for relation 1 and M/P for relation 2),
plus the special tag (pedestrian).

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00.09' E008°23.33'





More information about the talk mailing list