[postgis-devel] ST_MapAlgebra (was: ST_Value performance)

[Sandro Santilli]

On Tue, Jan 31, 2012 at 05:22:45PM -0500, Pierre Racine wrote:
> > Now I tried it and realized that "rast" in the expression refers to the pixel value
> > while I don't care about that.
> > Instead, I need the _position_ of the pixel.
> > That is, my expression is a function of the pixel position, not of its value.
> > 
> > Would it make sense to then provide that information as well as a placeholder,
> > in addition to the value ?
> 
> Yes that would be very useful. Could be 'rastx' and 'rasty'.
> 
> You would prefer 'pixval', 'pixx' and 'pixy'?

I'd always want geographical coordinates, not just x/y.
How about pval, pgeom, px, py ?

--strk; 

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