[postgis-devel] POINT EMPTY in WKB

[strk]

On Mon, Dec 06, 2010 at 12:30:31PM -0800, Paul Ramsey wrote:
> On Mon, Dec 6, 2010 at 10:01 AM, Paul Ramsey <pramsey at opengeo.org> wrote:
> 
> > A final possibility would be to hack POINT EMPTY into WKB, as
> > something like POINT(nan nan nan) or POINT(inf inf inf) or POINT(-0 -0
> > -0). There would be a danger there in platforms that have different
> > interpretations of what nan, inf or -0 are in binary.
> 
> I neglected to add a third possibility which would be to add another
> flag to the EWKB type number to indicate the presence of an empty
> geometry. This would also be backwards breaking since old-school EWKB
> handlers would, even if they stripped off the high bits, receive what
> to them was a degenerate piece of WKB (endian-int32 instead of
> endian-int32-double-double)

Give them the double-double .. some funny HEX string :)

--strk; 

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