On 14/08/2020 14:53, David Woolley wrote:
On 14/08/2020 12:46, Mateusz Konieczny via Talk-GB wrote:
If signage on the ground is gone or never existed then route relation
should not be mapped in OSM*.
In the long term, this could make OSM useless for motor traffic as
there is a general policy of decluttering signs. One of the arguments
for that is that everyone uses satellite navigators, so they don't
need the signs. I think is also used as an argument for why it can
take councils years to fix missing street name signs.
If OSM relies on on the ground signage, when the authorities rely on
virtual signage in online maps, it could lose a lot of roads!
That's a bit of an "extrapolation too far" I think. I don't think
anyone was talking about general highway signage, just addressing the
very real problem that happens when cycle routes change and signage
lags, and the problems that we have when, on a route that goes A-B-C-D,
Sustrans are no longer looking after the B-C part, but _everyone_
following the route will still need to get from B to C, so they'll have
to "join up the gaps" between the Sustrans-maintained parts.
The key question is what Robert asked at the top of this thread:
> We also might need to think about our tagging, as there will now be
> more levels of routes: Full NCN routes, other promoted named routes
> that aren't on the NCN.
... actually I'd add here a third category, where there are short gaps
in existing Sustrans routes. An example which I've mentioned elsewhere
is https://www.openstreetmap.org/#map=17/54.23978/-1.20491&layers=C -
Sustrans don't have NCN 656 running along the A170, there's a gap.
> How can we distinguish these in OSM?
> network=ncn and network=rcn are typically used for national and
> regional level routes rather than specifically the Sustrans NCN.
I'd suggest that it makes no sense, in the case of the example above, to
omit https://www.openstreetmap.org/way/38353700 from NCN 656. This is
what is in OSM now, and I think it makes sense to join the gap where
there is unambiguously only one way of getting from A to B. Perhaps
some sort of role in the relation could be used here to say either "this
isn't technically part of NCN656, but it's the only way of following
NCN656, so you're going to have to go along here whether you like it or
not". Other "no longer Sustrans but still a promoted named route"
sections could have a different relation role.
However I don't think that it makes sense to join up routes using any
sort of guesswork. Taking NCN 67 at
https://www.openstreetmap.org/#map=11/53.2344/-1.3726&layers=C as an
example - there's no point in pretending that it extends north of
Corbriggs or south of Chesterfield.
Another problem is that the on-the-road updates may not match what
Sustrans' new maps with dotted lines on them suggest that they will do.
The NCN1 marker at
https://www.openstreetmap.org/?mlat=54.30117&mlon=-0.44081#map=19/54.30117/-0.44081&layers=C
has recently been "re-stickered" to remove the Sustrans logo. As far as
I can tell that road section isn't on the list to be made
"non-Sustrans". I have no idea whether Sustrans' web maps are wrong,
Sustrans' volunteer has stickered the wrong sign, or (entirely possible)
I've misread the intent of the re-stickering.
Best Regards,
Andy
_______________________________________________
Talk-GB mailing list
Talk-GB@openstreetmap.org
https://lists.openstreetmap.org/listinfo/talk-gb