[OSM-talk] SteveC should decide

James Livingston doctau at mac.com
Sat Oct 3 04:24:22 BST 2009


On 03/10/2009, at 12:53 PM, Jeremy Adams wrote:
>  If different regions want to use the map for different purposes,  
> display different tags, etc then they can apply their localization  
> when they create their map.

It's not so much that there are different uses, but a lot of the  
assumptions and hidden implications in tags aren't the same. A lot of  
the tags are a bit Europe-centric because that's where OSM started,  
and where a lot of the mappers are. I'm not blaming anyone in Europe  
for this, it's just how it's developed. As such, people in other  
regions often take liberties with what the descriptions on the wiki,  
and historical consensus, to fit them to the local area.

If we want to have globally consistent tags across the world, we're  
probably going to have to go and modify a bunch of core tags that are  
extensively used everywhere. Like whether highway=* is a physical or  
importance thing, and what it actually implies. As I understand it,  
it's used consistently within some countries as the former, and used  
consistently within other countries as the latter. Either we have it  
not being globally consistent (see the International Equivalence  
table), or half the world will need to change.


> Otherwise there's no way for applications (routing and otherwise) to  
> know how to work across the whole globe.

They're always going to have to know local quirks. From the discussion  
a while ago about highway=residential, I got the impression that in  
Europe is has a semi-implied access=destination for the purposes of  
routing - that is, you shouldn't drive down a residential one unless  
you have to, because they're very thin. In Australia, we have a lot of  
residential roads that are wide enough for four cars (one parked and  
one lane, either way, so driving down random residential streets isn't  
uncommon.




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