[QGIS-Developer] Using memory layer in Processing with SAGA and GRASS

[Nyall Dawson]

On 26 April 2018 at 17:31, Benjamin Ducke <benducke at fastmail.fm> wrote:
>
>
> In the case of GRASS, this is a more complicated matter.
> GRASS uses a fully topological vector format and all
> input data will go through rigorous topology testing
> by default. The more intermediate steps, the higher
> the risk that data will get crippled in the process.
> Note that GRASS now has an alternative way of linking
> to external data instead of importing it:
>
> https://grass.osgeo.org/grass74/manuals/v.external.html
>
> So perhaps it would be a good idea for the QGIS GRASS
> provider to offer v.external as an alternative to
> v.in.ogr for piping QGIS vector layers into the GRASS
> backend (however, read "NOTES" on the page cited above!).

This was already done in 3.0 - if you check Processing Options, Grass
provider, there's a setting to use v.external instead of v.in.ogr.
It's on by default.

Nyall