[Proj] +axis switch to control axis orientation

[support.mn at elisanet.fi]

Frank Warmerdam [warmerdam at pobox.com] kirjoitti: 
> support.mn at elisanet.fi wrote:
> > Hello,
> > 
> > my opinion is that it is an improvement and since it is downwards compatible
> > it is also very welcome. My only concern is that it only works partially? An user
> > might expect it to do the hole work but it just did half of it? How could it be
> > implemented so that all routines used that switch?
> 
> Janne,
> 
> I presume your concern is that it has no effect on the pj_inv() and pj_fwd()
> functions.  It is possible to implement support for it within them rather than,
> or in addition to in pj_transform() but it would be more complicated for a
> few reasons and likely slower since the axis switching decision would need
> to be checked for every point rather than once for a whole array of points to
> be transformed.

I would like to have the support there also since if the user enters the switch
then he also expects to have the effect.

Why would that need to be checked for every point? Just write two different
loops and check it before entering the loop .. or something similar?

Janne