Sorry if I've not seen the old posts on this, the wiki pages are
contradictory which is why I asked the question.
In the UK we are defining Trunk or Primary based on some arbitrary
definition not on anything that is of use to any user or renderer.
What we should be mapping is reality, so that people can use that data
to build on. Whether a road is signed in Green, Pink or Purple tells a
user nothing, it may have a legal definition but that is all. The tag
we give it should tell the user something about the road's capabilities,
importance, size and potential timings/traffic flow. A Trunk road that
is a dual carriageway with a maxspeed of 70 mph is very different to a
Trunk road that winds around fields and has a maxspeed of 50 mph or less!
Jonathan
http://bigfatfrog67.me
On 03/11/2013 00:14, Tom Hughes wrote:
On 02/11/13 18:47, Jonathan wrote:
I'm not clear with the distinction of a Trunk road in the UK. The wiki
suggests a trunk road is "high performance roads that don't meet the
requirement for highway
<http://wiki.openstreetmap.org/wiki/Key:highway>=motorway
<http://wiki.openstreetmap.org/wiki/Tag:highway%3Dmotorway>" which to me
would suggest an A road that is a dual carriageway. Further on in the
wiki it says that any A road in the UK signed with "Green" signs is a
"Trunk" road.
I know of many "Green" "A" roads that aren't much more than country
lanes, they are definitely not "high performance" and I don't feel they
should be "Trunk" roads, I feel they should be "Primary" roads.
It's really very simple, and has been discussed here many, many times
before and I'm sure there are multiple pages on the wiki covering it.
First, forget the question of which roads are formally designated as
trunk roads by the Department for Transport (which is not very many
these days).
Second, understand that there is something called the Primary Route
Network defined by DfT which covers those A roads connecting specific
major towns. Those are the A roads with the green signs, and are what
we tag as highway=trunk. Other A roads are highway=primary.
In many cases those will be major roads, often ex trunk roads, but in
more rural areas like the highlands they might look more like a B road
does in other parts of the country. That is irrelevant though.
In the UK it is really only residential/unclassified/tertiary where
you need to make a judgement call. Everything else has a well defined
mapping:
Motorways => highway=motorway
Green Signed A Roads => highway=trunk
White Signed A Roads => highway=primary
B Roads => highway=secondary
Hopefully that will explain everything ;-)
Tom
_______________________________________________
Tagging mailing list
[email protected]
https://lists.openstreetmap.org/listinfo/tagging
