[OSM-talk] Fetch whole relation when parts of it are in bbox

Jon Burgess jburgess777 at googlemail.com
Wed Nov 7 20:56:04 GMT 2007


On Wed, 2007-11-07 at 15:09 -0500, Matthias Julius wrote:
> "Martijn van Oosterhout" <kleptog at gmail.com> writes:
> 
> > mapnik uses actual bounding boxes of objects to select them, so
> > problem doesn't occur...
> 
> How does mapnik define the bounding box for a single named node object
> like places?

A point is stored as a point.

When Mapnik renders a 256x256 tile it actually fetches and renders the
data equivalent to 512x512 and then cuts the tile down to the 256 square
in the centre. 

The mapnik osm.xml style renders text labels fairly small so the
important points generally manage to get within the 128 pixel zone
around the tile. 

	Jon






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