[Proj] How to access projection-factors in 4.8 (without projects.h)?

Greg Troxel gdt at ir.bbn.com
Mon Mar 26 07:01:34 EST 2012


Heiko Klein <Heiko.Klein at met.no> writes:

> Hi,
>
> I just read that the projects.h header is no longer available (publicly).
>
> Currently, I use projects.h to calculate the factors.k from the 
> polar-stereographic projection. Polar-stereographic projections can be 
> defined by 'lat_ts' or by 'k', and up to 4.7, I was able to access those 
> easily, e.g. when translating from a proj-projection to a projection in 
> FGDC:
>
> att["scale_factor_at_projection_origin"] = factors.k;
>
>
> This functionality is available in 'proj -V' (which still requires 
> projects.h) but not in the public API proj_api.h
>
> I think, as long as the commmand-line interface still requires 
> 'projects.h', not all necessary functionality is included in proj_api.h

If projects.h really is going to be a private header, it would seem to
be a bug that the command-line program proj uses it.  It's not strictly
a bug, but it should be possible write programs like proj with only the
public headers/library, so it's a clue.


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