[OSM-dev] Overlapping polygons - verboten or not?

[steggink at steggink.org]

Quoting the.promenader at gmail.com:

> One more question:
>
> I'm still trying to figure out how the OSM tile-rendering server   
> loads its data - does it look first in 'relations', then to any   
> related ways and nodes (top-down), or does it load all data   
> indiscriminately based on geolocation?
>
> Cheers,
>
> Josef.
> _______________________________________________
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> dev at openstreetmap.org
> http://lists.openstreetmap.org/listinfo/dev
>

Mapnik uses PostGIS. OSM data is loaded into PostGIS before it is  
rendered. See [1] for more information. The loading can be done with a  
tool like osm2pgsql.

Frank

[1] http://wiki.openstreetmap.org/wiki/Mapnik