[postgis-users] Rounding off coordinates

[Markus Schaber]

Hi, Strk,

On Mon, 28 Jun 2004 15:47:46 +0200
strk <strk at keybit.net> wrote:

> I've implemented a grid-based reduction function for postgis
> which in fact rounds off coordinates.
> 
> It currently take a reference point and
> a grid size (height, width of grid cell). Makes each geometry
> point stick on the grid and removes duplicated point (thus
> reduction).
> 
> If you are interested in supporting integration in postgis
> I'll work on that.

We'd appreciate this, but you should take care that your function does
not create invalid geometries when applied to polygonal types.

We did such reductions in java code, and later had some unexpected
problems when trying to calculate intersection()s of such polygons in
postgres.

Greets,
Markus


-- 
markus schaber | dipl. informatiker
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