r.external - was: Re: [GRASS-dev] some questions about future development

[Glynn Clements]

Markus Neteler wrote:

> >> Copied what over? r.external won't work unless the corresponding
> >> lib/gis changes have also been incorporated, and lib/gis was built
> >> with GDAL_LINK=1:
> 
> I have now backported all to GRASS 6.4.svn (locally) including the fixes
> of the last 2 hours (MAX etc fixes).
> 
> ...
> > Now r.stats works! Will try to (locally) backport to 6.4 now (for
> > monitor tests).
> 
> Done.
> COOL STUFF. I linked a GeoTIFF RGB orthophoto (600MB)
> and d.rgb works sufficiently fast.
> 
> Any objections that I submit the backport?
> 
> I assume that later the GDAL_LINK condition will become default?

It's reasonable enough to make it the default, although I really would
like to support a --without-gdal option (specifically, the ability to
only use GDAL for r.{in,out}.gdal and v.{in,out}.ogr, so that if GDAL
doesn't work, you only lose those modules, not the whole of GRASS).

AFAICT, the only "core" GDAL dependencies are the OSR stuff in
lib/proj and g.proj, and the vector library's support for v.external. 
In which case, it really ought to be possible to get a usable version
of GRASS with no GDAL dependency in any of the libraries or core
modules (e.g. g.proj, g.region).

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