[OSM-dev] Units in the Mapnik .xml file?

[Ulf Lamping]

Tom Hughes schrieb:
> I keep meaning to write a preprocessor to allow us to use zoom levels
> in the XML file and have them turned into scale values...
>   
Unfortunately, that's IMO just the wrong way to go.

In order to understand what these values really mean, IMHO it's a lot 
better to use scale values than the really arbitrary zoom levels (I know 
that they depend on DPI). When I had a look at the *various* ways people 
keep that kind of values in some xml file (mapnik, osmarender, mappaint, 
...), I had at least an idea what the values meant in the mapnik file, 
but *no idea* what the different zoomlevels of osmarender really mean.

I had a "deep look" at both osmarender and mapnik xml file, and to me 
the way mapnik is doing it seemed to be a lot better (e.g. osmarenders 
spreading settings across several files is an invitation for 
inconsistencies like different icons in different zoom levels for the 
same thing - which already appeared in reality).

So please do *not* bend the mapnik xml to look more like osmarender !!!

Regards, ULFL