[OSM-dev] Not filling polygon holes

[Brian Peschel]

On Tue, Jun 17, 2008 at 11:29 PM, Martijn van Oosterhout <kleptog at gmail.com <http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/dev>> wrote:
> On Tue, Jun 17, 2008 at 5:56 PM, Brian Peschel <brianp at occinc.com <http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/dev>> wrote:
> >/ (not sure if this should be here or on the mapnik list, so I put it on
/> >/ both.  Apologies for overposting)
/> >/
/>/ > I have seen a couple of discussions on the Open Street Map lists about
/>/ > multi-polygons.  And I believe I saw a comment of two about not filling
/>/ > polygons with holes.
/> 
> Mapnik supports polygons with holes just fine. Occasionally there are
> problems with the OSM data getting converted into the right format,
> but if you have properly constructed shapefiles it shouldn't be a
> problem.
>
> Have a nice day,

I have access to the mapnik source code.  I see the code where it 
supports multiple polygon in a single shapefile record (by looking  at 
the number of parts).  But it appears to be then returning each part as 
a polygon in the larger mapnik::polygon_impl.  Unless you are saying 
that the mapnik library understands the shapefile direction part and is 
not filling counter clockwise shapes (as defined by the shapefile 
definition)?

Hmmm...  This probably makes more sense on the mapnik mail list, I will 
post this over there.

- Brian