[postgis-devel] ST_MapAlgebraExpr(): Raster aggregates?

[Tom van Tilburg]

Hi list,

At the moment I'm looking at the option of turning vector maps with 
discrete (non overlapping)  data into rasters with the help of the 
WKTraster functionality.
At the moment I do as follows:
1. Collect (aggregate) al geoms from the same class
2. Make the into a raster with St_AsRaster()
3. Repeat for all classes
4. Merge all resulting rasters into 1 with ST_MapAlgebraExp()

This step 4 I have to repeat (nest) a lot of times (for every class I 
have in my vector data). It would be great to have St_MapAlgebraExp() as 
an  aggregate function instead of just 2 rasters. This would greatly 
simplify the process of turning land use data from vectors/topology into 
raster. Is there any such thing available or in the make?

Regards,
  Tom