[postgis-users] ST_MakeValid

['Sandro Santilli']

On Mon, Apr 16, 2012 at 03:05:21PM -0400, Stephen V. Mather wrote:
> > IIRC there's a difference with a multipolygon composed by two
> > overlapping rectangles.
> 
> Rereading, does ST_MakeValid also test for overlapping polygons? 

It handles those too, yes.
Basically it nodes and polygonizes all boundaries of input polygons
and then maximizes the vertices retained in output by toggling
between interior and exterior at every boundary. When impossible,
the line is retained as a linestring.

--strk; 

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