[Talk-GB] trunk roads

[David Earl]

> > See http://www.camcycle.org.uk/map
>
> Thanks for this information. It seems that no one is keeping the data
> on the roadworks up to date, as it is from 1999, nearly 8 years ago.

Err... it's only been live for a year or so, so it's more likely a typo
somewhere.

> It only appears to work in the Cambridge area, which is no use to
> me. :-(


Well it is for Cambridge Cycling Campaign!

But that's not entirely true. The system works by people tracing routes:
basically making the topological connections that is OSM's starting point.
It's a wiki so anyone can do this for their own area. If it were done from
an OSM base map, the data would be divorceable from the map (though would
have to be CCSA licensed under the terms for OSM)

OSM isn't adequate as it stands because the richness of the cycle route
types isn't quite enough - at least for us. For example, where a road has
cycle lanes and pavement cycling, both are represented *and graded* so that
if you ask for the 'quietest' route you'll get the pavement and the
'fastest' route you'll get the road. It also gives you the exact path to
take through junctions, much more detail than OSM contains, where most
junctions are simply single nodes.

> I'm sure we can either come up with our own route planning
> algorithm or find someone who will do it in an open source environment.

As I said, the routing software is not derived, but the route data itself is
tainted by Google. If it were done from OSM, it wouldn't be PD, but could be
CCSA.

David