[OSM-talk] Mapnik: strange prioritisation/appearance of place names

[David Earl]

On 23/03/2009 12:13, Adam Schreiber wrote:
> On Mon, Mar 23, 2009 at 8:08 AM, Elena of Valhalla
> <elena.valhalla at gmail.com> wrote:
>> finding a working algorithm that uses only objective data and is
>> always able to select the proper item to print would be excellent, but
>> also probably not feasible in real life.
> 
> Population?  People can vote importance with their feet.

Population's not enough. Some places "punch above their weight" - the 
example I like to use is Hay-on-Wye in Powys. It's under 2,000 people 
but is most clearly an important market town for the surrounding area. 
In population it would be a modest village, but it is more important 
than that.

Similarly, many US states have capitals which would otherwise be 
relatively insignificant towns/cities (take Albany NY for example). 
Their administrative function makes them more important than population 
alone would suggest.

I think there's lots of factors, many of them subjective and many down 
to what people in a place themselves think.

On 23/03/2009 11:52, Kærast wrote:
 > We need to keep the village/town/city tags because it is important to
 > know the official designation of a place, so what we need is a tag to
 > designate how important the place is and therefore what zoom levels it
 > shows on.  However, this would be tagging for the renderer and
 > therefore considered by most to be inherently bad.

place currently has nothing to do with official designation. Nearly all 
incorporated places in the US are "cities" even if they only ahve a 
population of a few hundred; they are not marked as place=city as, for 
the reasons mentioned in the original post, it would make it 
nonsensical. In that respect, marking St Davids and even Ely (pop 
15,000) as "city" is arguably wrong, certainly different to how it's 
been done elsewhere.

This is another old chestnut of a topic which, like "highway=thing isn't 
the official designation" comes round every couple of months and since 
there are as many differing views as people contributing to the 
conversation (often more), no concensus means nothing ever happens.

David





David