[Tagging] Tunnels and bridges

[Pieren]

On Thu, Jan 31, 2013 at 3:51 PM, Malcolm Herring
<malcolm.herring at btinternet.com> wrote:

> Maybe I am missing something from your proposal. I had understood it to mean
> that bridges should be mapped as distinct features, separate from the ways
> that pass over and under. Therefore, "bridge=..." tags on the ways would
> become redundant and remove the ambiguity and messy rendering that they
> cause when more than one way crosses the same bridge.

Yes. Use "bridge=*" only once, either on the highway way (linear) or
on a polygon (surface). But it's preferable to use a second tag to
distinguish the linear vs the surface modeling. Otherwise we don't
know if an OSM closed way tagged "bridge=yes" is the surface or
something really linear where the "highway" tag is missing.

> Also, wheat exactly did you mean by "Connect the ways running over the
> bridge to this structure"? This implies a relation to make the connections,
> but you then go on to deprecate the use of relations.

I guess it's just about a node put on the intersection between the
highway(s) and the polygon. But I'm not sure if this is really
required (the same question raises when a highway is crossing an
administrative boundary or a landuse).

Pieren