[QGIS-Developer] Updating qgis:rastercalculator to work better in models

[Luigi Pirelli]

hmmm... working on your test data, btw IMHO raster calculator should be
dropped in favor of a numpy based expressions... we should also consider
the maintenance aspect for the future! raster calculator is not hard to
maintain (harder is the interface to integrate in modeler that the
calculator itself) but it's syntax is really poor.

I didn't investigate how we can import gdal code (that's a python code)
into qgis... or better create a gdal/ogr interface directly to qgis data
(kind of R dataframe access)

Luigi Pirelli

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On Tue, 3 Jul 2018 at 15:02, Rudi von Staden <rudivs at gmail.com> wrote:

> On Mon, 2 Jul 2018 at 18:30, Luigi Pirelli <luipir at gmail.com> wrote:
> > My question (poll) is... does it make sense to patch native raster calc
> instead of override gdal_calc limitation?
> > Make sense to solve raster calculator bug only if these bugs are generic
> and does not depend of the specific organization of the raster calculator
> GUI.
>
> I've also encountered the issues using gdal_calc with non-homogenous
> layers (which is why I started looking at the raster calculator).
> Another reason I would like to see the native calc working is because
> it runs much faster than having to wrap third-party tools. I've found
> gdal is generally not too bad, but my use-case is still to build a
> model and loop through it hundreds of times, so every second counts.
>
> My feeling is that it wouldn't take much work to get the raster
> calculator at least usable in the modeler at its current level of
> functionality. Improving gdal_calc or implementing more powerful
> operators in native raster calculator can then be a secondary, more
> involved process.
>
> Rudi
>
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