[OSM-dev] (Multi)Polygon handling

Peter Wendorff wendorff at uni-paderborn.de
Fri Jul 13 18:53:30 BST 2012


Am 13.07.2012 18:31, schrieb nimix:
> Hi, I just has a look at this... Mapnik indeed has no such requirement. But
> it requires inner rings of multipolygons do be in a different orientation
> than the outer ring. Hence it is reasonable to ensure that by just making
> all outers cw and inners ccw.
That won't work everywhere:
If a polygon is outer way of multipolygon 1 and inner way of 
multipolygon 2, it would require to be cw and ccw.
Therefore as long as the way is a way (independent of ~ or part of 
multiple ~ respectively) multipolygons, it's direction can be arbitrary 
and cannot be fixed to be one particular for multipolygon restrictions.

regards
Peter



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