[postgis-devel] lwgeom_calculate_bbox

[Sandro Santilli]

Checking some more by myself I've found that
ST_Envelope is returning the double precision box
while the cached box is in single-precision.

That should explain...

But, aren't we using ST_Envelope for speeding up
Rasters queries ? If we're going to drop the BOX2D
type, how else would we go with fetching a cached BOX ?
Should we cache a full box and only strip-down in indices,
if at all ?

--strk;

On Sun, Mar 20, 2011 at 06:01:21PM +0100, Sandro Santilli wrote:
> I was looking at ST_Envelope implementation to see how much
> speed juice we could extract from it and found thi code:
> 
>  LWGEOM *lwgeom = pglwgeom_deserialize(geom);
>  if ( lwgeom_calculate_gbox(lwgeom, &box) == LW_FAILURE )
>  ...
> 
> Did something change about cached bboxes ?
> Or, why are we blindly computing that again w/out even checking
> if a cache exist already ?
> 
> I kind of recall we had a get_bbox(lwgeom*) or something which would
> either return the cache or compute a new one...
> 
> Can anyone shed a light on this issue ?
> 
> TIA
> 
> --strk; 
> 
>   ()   Free GIS & Flash consultant/developer
>   /\   http://strk.keybit.net/services.html
> _______________________________________________
> postgis-devel mailing list
> postgis-devel at postgis.refractions.net
> http://postgis.refractions.net/mailman/listinfo/postgis-devel

-- 

  ()   Free GIS & Flash consultant/developer
  /\   http://strk.keybit.net/services.html