[geos-devel] Order of results in GEOSDelaunayTriangulation

[Sandro Santilli]

On Mon, Sep 04, 2017 at 07:10:27PM +1000, Nyall Dawson wrote:
> On 4 September 2017 at 17:31, Sandro Santilli <strk at kbt.io> wrote:
> > On Mon, Sep 04, 2017 at 04:33:28PM +1000, Nyall Dawson wrote:
> >> Hi list,
> >>
> >> Quick question - is there any logic to the order of geometries in the
> >> collection returned by calling GEOSDelaunayTriangulation?
> >>
> >> I'm looking for a way to reliably associate the parts of the returned
> >> collection with the original input nodes. Ideally I'd like to avoid
> >> having to test for intersection for each of them.
> >
> > I don't think there's any promise about output order, so even if you
> > find one now it won't necessarely remain.
> 
> That's what I suspected. How about geometry user data, could that
> potentially be used here?

I'm afraid you'll have to test. And same precautions apply:
is it documented as being supported ?

I'm adding Martin Davis in Cc as that class is ported from JTS.

--strk;