[Talk-GB] Schools Progress Tracker Update

Ed Loach edloach at gmail.com
Sun Jan 24 12:56:04 UTC 2016


> > The site relation page however
> >
> http://wiki.openstreetmap.org/wiki/Relations/Proposed/Site#Prop
> osal
> > suggests it should be multipolygon and not site -
> > "For example the tag amenity=school describes the perimeter of
> the school grounds, for schools with multiple sites the multipolygon
> relation can be used. Usage of a site relation is not appropriate
> here."
> 
> Hi - it's an interesting ambiguity between "multipolygon" and "site".
> I actually think the thing you quote is a bit mis-worded, and what
> they're trying to say (I'm inferring from the other sentences in the
> wiki page...!) is that you should use "multipolygon" to aggregate
> multiple buildings (for example) that sit within a single grounds,
> whereas you should use "site" to aggregate multiple objects that are
> more widely separated ("scattered throughout across the city" is the
> wiki guidance).
> 
> This shows that OSM could perhaps live without the "site" relation if
> people simply used multipolygons. However I think people tend to
> assume multipolygons are quite localised, which probably makes a
> difference to how they are rendered (e.g. one label for a whole
> multipolygon, vs one label for each member of a site).
> 
> Anyone else got input on this? I might tweak the wiki, if it seems I'm
> not in the wrong.

I personally don't see the difference between our case here (a school with multiple sites/campuses) and the university example provided on the page:
http://wiki.openstreetmap.org/wiki/Relations/Proposed/Site#Examples
Although having said that the amenity=university wiki page suggests a multipolygon should be used (an unanswered question on the talk page there asks how to put the different campus names on the relevant member areas).

However, I think in the standard render that Site gets no labels and multipolygons gets one for each outer way (based on local woods with the name all over the place). Not that how things render should affect our choice.

The other bit of text on that wiki page though is "The features should have a close geographic relationship, usually within the same town." I'll cling to the word 'usually' if we decide to use site relations for multi-campus schools, as Colchester Institute has a Clacton campus, and Tendring Technology College has the main school in Frinton and the second campus in Thorpe-le-Soken. I've not yet worked out what to do about the mapped Adult Community Learning centres that don't have edubase refs and are scattered across Essex (there are three centres already mapped and tagged as amenity=college in the CO area - Harwich, Clacton and Colchester) - this relates https://www.essex.gov.uk/Adult-Learning/Pages/Default.aspx

So I'm currently unconvinced by the site relation, especially as the discussion on its talk page suggests the proposal is still evolving - it seems I commented on it nearly 5 years ago and since forgot.

Ed




More information about the Talk-GB mailing list