[Talk-us] Per-State relations for the Appalachian Trail

[Kevin Kenny]

On 05/03/2016 03:09 PM, OSM Volunteer stevea wrote:
> In the USA, partly because we are such a geographically large part of 
> the North American continent and partly because each of our fifty 
> states is sovereign, I find that breaking apart very large relations 
> so they are across a single state at a time (then perhaps these are 
> collected into a super-relation) is often (though not always) a 
> sensible approach.  It is part size (large relations with vast numbers 
> of members are unwieldy), it is part “what sort of an entity is this 
> politically?"
>
> For example, there is a note in OSM’s Amtrak wiki page on the 
> route=train relation for the California Zephyr:  "The relation is said 
> to be so big it is hard to work with.”  That is something we might 
> take to heart and break apart the relation into statewide components. 
>  I haven’t done that, but somebody might, after considering that it 
> makes editing easier, and that state-at-a-time is a good way to do 
> this.  Even a simple web browser request to display this relation 
> results in "Sorry, the data for the relation with the id 905830, took 
> too long to retrieve." The practicality of potentially better avoiding 
> edit conflicts has been mentioned, and is also true.
>
Breaking apart the AT into separate relations - ideally with a 
superrelation joining them - would be sensible, I think, but be careful 
about the assumption about state lines. The AT literally spends a good 
many miles with the hiker having one foot in North Carolina and the 
other in Tennessee - the ridge that it follows is the state line.

We also, I think, need to put some more thought simply into the support 
of large relations. I've recently found that even the New York Long Path 
(only a fifth the length of the AT) crashes JOSM (I haven't yet 
diagnosed the problem) and wound up editing in Meerkartor instead. 
Trails, highways, rivers, railroads, we have a good many places where 
things reasonably and predictably break down into thousands of parts 
over thousands of km, and I don't think we yet have a unified theory of 
how to handle them.

-- 
73 de ke9tv/2, Kevin