[ptx] Projections

[Pablo d'Angelo]

Hi Peter,
> 
> My ideas are based on the fascinating paper: "Squaring the Circle in
> Panoramas"
> (http://www.vision.caltech.edu/publications/publications.html).  

Yes, thats a very nice one. Actually, I have meet the authors at the ICCV
conference were it was presented.

> That paper also discusses the Transverse Mercator projection so I
> would be interested in having that in hugin as well. Equations again at
> http://mathworld.wolfram.com/MercatorProjection.html.

I'll add this as well.

ciao
  Pablo