[GRASS-user] kml topology... ?

[Nikos Alexandris]

On Thu, 2008-02-28 at 09:15 -0800, Dylan Beaudette wrote:

Thank you for your reply Dylan!

> On Tuesday 26 February 2008, Nikos Alexandris wrote:
> > Continuing my small quest with kml files... and bombing you with simple
> > questions ;-p
> >
> > are kml files carrying topology information besides coordinates?
> 
> I doubt it. As far as I know they are just "simple features".
> 
> >
> > I needed to manually correct a kml file which looked very bad after
> > importing in GRASS (with -c  otherwise it was not useful!)
> 
> i am not surprised that a KML file resulted in a topologically broken file. 
> These days everyone and their brother are creating KML via all sorts of 
> methods-- most of which have little notion/concern for 
> topological-correctness. 
+1
> 
> > Automatic cleaning is really not useful even after trying to feed with
> > logical thresholds the various tools.
> 
> Try opening the file with v.digit and look for oddities.

Had to correct (almost) everything. Tha data are supposed to come from a
GPS measurement session.

All polygons were open after importing in GRASS. Yet there were
centroids inside this virtually closed boundaries. And the strange thing
is that one (call it) centroid was out of the virtual boundaries... 

Don't know, maybe my mistake for this last statement about the centroid
falling out.

Cheers!