Geometry Boost List: [ggl] WKT empty

Subject: [ggl] WKT empty
From: Barend Gehrels (Barend.Gehrels)
Date: 2009-06-12 16:53:40

Hi list,

About WKT support. Many applications / libraries / databases support the 
option "EMPTY", so
LINESTRING EMPTY
POLYGON EMPTY
for empty geometries.

I cannot find that in the OGC specifications (if someone knows the 
document number, it is welcome).

However, if many do it might be reason enough to support it. We support
LINESTRING() and POLYGON(()) for an empty line or polygon, and a POINT() 
will result in a point with zero-values. But adding EMPTY will increase 
interoperability.

Regards, Barend