On Thu, Oct 28, 2010 at 7:48 AM, Ziegler Stefan <stefan.zieg...@bd.so.ch> wrote:
> Hi Giuseppe
>
> thanks for looking into this. Do you think it's worth filling out a bug 
> report since the nearestNeighbor method does not the  keep the promise or is 
> this the normal behaviour of a spatial index based method?

Spatial index uses only the bounding boxes of geometries for two
reasons: most importantly the intersection test (used when traversing
the data structure) is much faster when compared to testing
intersection of real geometry. Second, this would require spatial
index to store all geometries - this memory overhead can be
significant for bigger layers.

So as David already suggested, to ensure you are really working with
the nearest geometry, you should check the real distance.

Regards
Martin
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