[Qgis-developer] grass module don't appear

[Giovanni Manghi]

> Only solution to install in some way grass64.

yes

> However r.mapcalc is present in grass7 as well as r.null, I thought if would
> have added r.null.text and r.mapcalc in
> /usr/share/qgis/plugin/processing/algs/grass7/description
>
> those modules should have been present in the processing toolbox, isn't it?
>
> Can somebody listed the operations to add a grass module to a processing
> toolbox?


no, they can't be added right now:

from http://hub.qgis.org/issues/6894

"r.mapcalc takes the name of raster layers to use...which is a
problem, since those names are temporary names, because layers have to
be imported into the mapset. This could be changed, but will
definitely take time."

anyway we were just pointed that there is a feature request in grass 7
to add a new flag that would solve the problem and allow to use
r.mapcalc in processing without needing any changes (in processing).

r.null can't be added because processing works in a way that a new
output is always created from a input, so grass modules that *modify*
inputs instead of creating new outputs are not supported at the
moment, see

http://hub.qgis.org/issues/6893

cheers

-- g --