[OSM-talk] Mulltipolygons and Mapnik

Cartinus cartinus at xs4all.nl
Sat May 31 21:05:01 BST 2008


On Saturday 31 May 2008 21:26:53 Jon Burgess wrote:
> On Sat, 2008-05-31 at 20:08 +0200, Cartinus wrote:
> > I forgot to mention:
> >
> > A hole filled with something else IOW different tags on the outer and
> > inner polygons only works in T at H/Osmarender
> >
> > http://tile.openstreetmap.nl/?zoom=17&lat=52.06243&lon=5.10283&layers=000
> >000BF
> > http://tile.openstreetmap.nl/?zoom=17&lat=52.06243&lon=5.10283&layers=000
> >00B0F
> > http://tile.openstreetmap.nl/?zoom=17&lat=52.06243&lon=5.10283&layers=B00
> >0000F
>
> I'm not certain which polygons you are talking about here. If you are
> talking about the ones to the NW, then those look like they are marked
> with area=yes. Support for area=yes was only recently added to the
> osm2pgsql code and the rendering styles have not been implemented yet.
>
> Mapnik will render inner areas with different tags. It uses the area of
> the polygons to figure out the render ordering. Smaller areas always
> render on top of larger areas of the same layer. If the layer tags
> differ then this will take precedence.
>
> 	Jon

The area=yes stuff has nothing to do with multipolygons. There is only one 
multipolygon in the view I linked to. (relationID=9214; name=Meubelboulevard)

Click on the first link. Right in the middle you'll see a park surrounded by a 
retail area.

Now switch to either of the two Mapnik renders. At the western end of where 
the park showed in the Osmarender view (just below the parking icon) you can 
see some edgeline between retail and retail (except the inner retail should 
be park). Around the rest of the park this is obscured by roads.

-- 
m.v.g.,
Cartinus




More information about the talk mailing list