[postgis-devel] ST_GeometrySplit

[strk]

On Wed, Mar 10, 2010 at 11:49:18AM -0800, Chris Hodgson wrote:

> Right-side vs left side can be ambiguous too... an example is a circle 
> or spiral that is split by a line on only one side.

Argh, you're right. Here's a simple example:


    +-------+ 
    |   ^   |
    |   |   |
    |  ?|R  |
    +-----> |
        |   |
       L|?  |
  IN -------+
        |
       CUT

I marked with 'L' the part which is on the Left and with R
the part which is on the Right of the cut line.
The question mark is for the part which is both
on the Right (lower intersection point)
*and* on the Left (higher intersection point).

Maybe Martin has some neat topological rabit in his hat ?


--strk; 

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