[postgis-devel] ST_GeometrySplit

[strk]

On Wed, Mar 10, 2010 at 08:51:18AM -0300, George Silva wrote:
> Hello guys,
> 
> AFAIK, ArcGIS only handles the first case. One geometry splitting another,
> even in multiple pieces, in case of the aforementioned C shape linestring.
> 
> We should return multiple parts, as many as necessary: example, imagine
> multiple "C" shape linestrings concatenated together:
> 
> ___a________start
> |__ b___
> ___c___|
> |__ d___end
>      e
> 
> In this case we would have 5 parts (I'm not sure if you all can see it...).
> 
> Although the splitter line can be as complex as the user wants, it's a
> single line.

What kind of multi-part does ArcGIS returns ?
A multiline in the "split line by line" seems good to me,
but a multipoly in the "split poly by line" will be invalid
as components would be "touching" on the split line.

--strk;

  ()   Free GIS & Flash consultant/developer
  /\   http://strk.keybit.net/services.html