[Qgis-developer] some questions about GRASS features in QGIS

[Radim Blazek]

On Sat, Mar 9, 2013 at 5:40 PM, William Kyngesburye
<woklist at kyngchaos.com> wrote:
> I'm thinking about a packaging idea for bundling GRASS in the OS X app and need to know the extent of GRASS capabilities in the QGIS plugin. (I don't use GRASS in QGIS except to load GRASS layers, and that very rarely)  I'm trying to figure out if there is anything I can trim out of the bundled GRASS.
>
> - Can the plugin access/start the GRASS GUI?  I mean just the full GUI started with g.gui.  Is there really any benefit to doing this in QGIS?

No. My original idea of GRASS plugin was to only support those modules
for which we have robust and friendly enough GUI in the plugin.

> - Can the plugin use the command mini-GUI things (whatever they're called), that start when you run a GRASS command without parameters?  Seems redundant if it can, since the plugin has it's own GUI forms for filling in command parameters.

In the theory it could if a command is run from shell, but that was
not intention of the plugin. Again, the idea was either plugin GUI or
nothing.

> - Then there are a couple tools that only run in a small GUI interface, like NVIZ (in its multiple forms).  How does the plugin handle these?  Not at all, or let them run as is?

Unfortunately that commands were also added to the plugin modules
instead of just implement 3D view in QGIS.

> - Does the plugin initialize the GRASS environment completely on its own, or does it use any of the GRASS startup/init shell scripts?

Yes, on its own, in QgsGrass::openMapset() or QGIS may be run in GRASS
shell which was previously set up by standard GRASS start up script.

> - can the plugin run arbitrary GRASS scripts or modules (ie user scripts and addon modules)?

>From shell only, until user modifies plugin modules configuration.

Radim

> -----
> William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
> http://www.kyngchaos.com/
>
> "Those people who most want to rule people are, ipso-facto, those least suited to do it."
>
> - A rule of the universe, from the HitchHiker's Guide to the Galaxy
>
>