[Talk-us] Highway Tagging Consensus to Improve OSM (and address some of 41 latitude's concerns)

Nathan Edgars II neroute2 at gmail.com
Fri Oct 15 19:12:28 BST 2010

On Fri, Oct 15, 2010 at 1:58 PM, Phil! Gold <phil_g at pobox.com> wrote:
> * Nathan Edgars II <neroute2 at gmail.com> [2010-10-15 13:32 -0400]:
>> > Should we use the postal code everywhere for nationwide consistency or
>> > should we use the prefixes that locals use?  If we use postal codes, what
>> > should we do about county or town roads?
>> We should use no prefix for state roads to make shield adoption
>> easier. We place everything in a generic shape unless it has a prefix;
>> since state roads would be in a generic shape anyway, it's pointless
>> to add a prefix.
> I disagree with this.  I would like to be able to do state-specific
> shields, and putting a state prefix in is a) not incorrect and b) allows
> for easy disambiguation of *which* state network the road belongs to.  I
> realize that is also kind of an argument for the "postal abbreviation"
> approach, since the "local usage" approach can be ambiguous.

State highway shields are not always designed for legibility on a map.
For example, to get the number the same size as with a generic rounded
rectangle, http://commons.wikimedia.org/wiki/File:Colorado_7.svg takes
up four times as much space.
> From the perspective of keeping the current rendering, I think it makes
> more sense to put some prefix in.  Since everything currently gets the
> same type of shield, differing only in color, having an appropriate prefix
> makes network membership a lot more obvious.

Knowing which state you're in does too, given the current convention
in some places of no prefix for a state highway.
> If you do want to go without having a prefix for state roads, what do you
> propose for county, town, or other more local roads?

I use CR for county roads (other places might use CH or CTH), and
lesser systems would use their own prefixes. In the US, the state is
the highest level of government that maintains a large connected
highway system, and general practice on maps is to use a generic
shield for state highways. Both of these make the choice of no prefix
for state highways a good one.

I'm not actually opposed to using a state-dependent prefix like SR in
Florida and PA in Pennsylvania. But it seems pointless.

But there is no one-size-fits-all solution. Virginia has two types of
state routes, one (primary) in a triangular shape and the other
(secondary) in a circle. Both are officially SR x or VA x. Right now,
many are incorrectly tagged (VA x for primary and SR x for secondary),
probably in the mistaken belief that SR means secondary route rather
than state route.

Tennessee also has a signed primary/secondary distinction, but a
single route can change from one to the other. So here even a relation
wouldn't help.

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