[Proj] Help with use of swisstopo NTv2 grid shift ?

[Sandro Santilli]

On Thu, Jan 26, 2012 at 08:37:27AM +0000, Mikael Rittri wrote:
> On ???, Sandro Santilli wrote:
> >
> > Now next step would be making such transformation available with a single > proj call.
> > 
> > Would it be possible to create an init file containing all "pretending"
> > referenced set of working transforms ?definitions so to be able to
> > use <CH1903+> as the pivot and <CH1903>, <CH1903/LV03>, <CH1903+/LV96>
> > and maybe <WGS84> to have a self-referenced set of working transforms ?
> > 
> > Is that what IGNF file is all about ?
> 
> I don't think I understand these questions. 

I'd like to understand the existing options to provide the CH1903+ to CH1903
as an easy call to proj4 lib, so that any proj4 client would be able to do
that transformation w/out fiddling too much (with chains of transforms).

I had the impression that the IGNF init file had the same aim (for Franch
projections), but I'm probably wrong.

--strk; 

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