[Tagging] Clarification on the role link in route relations

[Zeke Farwell]

On Thu, Jan 13, 2022 at 2:15 PM Dave F <davefoxfac63 at btinternet.com> wrote:

> I'm well aware of route relations, of all types, but what have these to do
> with 'destination:ref*' tags on /ways/?
>
> How does routing software, which "lacks support for the 'role' tag" of
> route relations  "cause problems for any editor, QA tool, or data
> consumer"? It makes no logical sense. (quotes from Minh's original post)
>

We're just trying to determine if there is a reasonable use case for the
link role in a road route relation.  The only reason destination:ref is
part of the discussion is because the only use case we've been able to
think of for the link role is already handled by destination:ref.

<https://wiki.openstreetmap.org/wiki/Role:link>
The wiki defines 'role=link' <https://wiki.openstreetmap.org/wiki/Role:link>
as:

> Link roads (highway=*_link) from and to the route. See highway
> <https://wiki.openstreetmap.org/wiki/Key:highway>=motorway_link
> <https://wiki.openstreetmap.org/wiki/Tag:highway%3Dmotorway_link>.
>

Mappers are following this documentation and including on/off ramps in
route relations with role=link.  In most cases, an on ramp leading to a
numbered route is generally not considered part of that route.  To indicate
which route it leads to, they way gets tagged with destination:ref.  So
also including it in the route relation with the link role doesn't seem to
add any information.  Given this we're thinking it makes sense to remove
this suggestion from the wiki.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/tagging/attachments/20220113/0a43c875/attachment.htm>