[QGIS-Developer] Proj 7 auto grid download

[Nyall Dawson]

On Fri, 20 Mar 2020 at 18:55, Jürgen E. Fischer <jef at norbit.de> wrote:
>
> Hi Jeremy,
>
> On Fri, 20. Mar 2020 at 19:26:03 +1100, Jeremy Palmer wrote:
> > Why not ship with the same grids that come with proj-datumgrid (or what
> > QGIS typically ships in MacOSX and Windows.
>
> In PRØJ 7 the grid files were turned to tif and are not packaged individually
> anymore, probably because proj can downloaded them individually on demand now
> - but we apparently don't use that.

Not just QGIS. The auto-download behavior is an opt-in switch for
applications, it's not the default behavior.

I can't find any application which use the CDN by default -- searching
github for proj_context_set_enable_network only gets hits in proj
itself. And I'd really like consistent behavior here, so that users
who install QGIS through osgeo4w can get the same transformation
results regardless if they use QGIS application, GDAL command line, or
GRASS tools via processing... (which is why I keep coming back to the
"screw it, this is too complex to solve case-by-case, lets just
install them ALL for EVERYONE" option).

That said, users CAN still enable this for any application by setting
the environment variable PROJ_NETWORK. I'd be interested to hear
results if someone on a proj 7 build wants to test how this actually
impacts QGIS in practice.

Nyall