[Gvsig_english] QUESTION gvSIG 1.9 (BN 1253) -- Corrupted Polygon / Create new polygon using nodes

[Antonio Falciano]

Il 01/07/2010 10.56, Simon Cropper (Botanicus Australia Pty Ltd) ha scritto:
> Hi,
>
> I have inherited a polygon -- nodes in the polygon do not run
> sequentially from clockwise or anti-clockwise. This is throwing an error.
>
> I was able to extract the nodes from the polygon but have had problems
> finding the routine to create a new polygon using these points (there is
> no holes in the polygon).
>
> Can anyone please point me to a suitable routine?

Hi Simon,
you can try with the SEXTANTE library: in detail, applying "Minimum
enclosing shapes" (Convex hull) on vertices and then subtract the more
external triangles (selected manually) computed with "Delauney
triangulation". This is a quite huge task, also known as "Concave hull".
I don't know if this problem has been solved in GFOSS world...

Cheers,
Antonio

-- 
Antonio Falciano
http://www.linkedin.com/in/antoniofalciano