[OSM-talk] Divided roads proposal

[Anthony]

On Thu, Dec 3, 2009 at 12:38 PM, Steve Bennett <stevagewp at gmail.com> wrote:
> Well, put it this way: if this was implemented, I would duplicate far
> fewer roads in future.

If it worked (and I really haven't delved into the details enough to
check), I might be convinced to add division information where I
otherwise wouldn't bother (because the current method of creating a
dual carriageway is a pain).

> I don't know if I would go around converting
> existing ones, though.

If you don't know....that scares me.

> If a router ignores the tags, it will occasionally try and send you
> through a barrier.

For a U-turn?  Whether or not a U-turn is legal should probably be
treated as "unknown" by routers in most cases.  We're currently not
really mapping that at all.

OTOH, if you're talking about a left turn, I thought the point was
that this would be handled by turn restrictions just like would be
done currently.

> If a renderer ignores them, then it might be hiding
> important information from the consumer. But there are certainly
> already plenty of divided roads which are not marked as such.

Yeah, I see this as maybe a potential solution in between using a
single unmarked way and using a dual carriageway.  Although, looking
at the proposal, it doesn't look finished - something you seem to
admit yourself.