[GRASS-dev] rasterlib and file layout

[Glynn Clements]

Martin Landa wrote:

> first step towards rasterlib in GRASS 7 has been done [1]. Let me
> suggest the second one. The file layout should be consolidated.
> Currently vectors are located in 'vector' directory, 3d rasters in
> 'grid3' (or 'g3cell') - should be 'raster3d'.
> 
> I would vote for similar approach for raster files in GRASS 7. So
> 
> raster/name/cats
> raster/name/cell
> raster/name/cellhd
> raster/name/cell_misc
> raster/name/colr
> raster/name/fcell
> raster/name/hist
> ...
> 
> Any comments?

Agreed. Except that there's no reason for the cell_misc directory to
exist in such a layout.

One of the main reasons I added r.external was so that we could do
this and fall back to GDAL for accessing the legacy layout. We really
don't want to be supporting both layouts concurrently.

However, for that to work, we need to make GDAL's GRASS support
independent of the GRASS libraries.

To avoid legal problems with GDAL binaries (libgis is GPL, not LGPL),
the code would ideally be re-written from scratch (AIUI, FP and null
support were added after the switch to GPL, so using the public-domain
CERL code won't get you very far).

If anyone is interested in doing this, I can write up documentation of
the file formats.

-- 
Glynn Clements <glynn at gclements.plus.com>