[geos-devel] geometry validation and simplfiy problem

[zhangjing]

thanks Martin,

>Not currently, but it would be nice to have.  I have done some work in
>this direction, but it's not really in a releasable state.

yes, really looking forward. 


>When you "simplify" a polygon with a hole which crosses outside the
>outer shell, what happens to the part that is outside?  Does it
>disappear, or become another polygon?

i believe it will become another polygon. i think all i want is to make the 
LineRings into topology correct polygon(multipolygon). 

>One thing you can do which should work almost all the time is to run
>buffer(0) on the invalid polygon.  Buffer is very tolerant of bad
>topology, and will generally fix the polygon in the way I suspect you
>are looking for.
>

i will try buffer(0). will buffer(0) simplify a self-intersected polygon?

thanks.