Equirectangular and cubic panoramas

This post is here to demonstrate the difference between two different ways how full spherical panoramas can be saved.

Most panoramas on panoye are equirectangular:

On equirectangular panoramas some lines are distorted and some aren't. Horizontal lines at the center are straight and so are all vertical lines. All other lines are more or less distorted. Lines closer to the top or bottom are more distorted than those near the center.

That's why even non-spherical panoramas with wider visible field (i.e. bigger height compared to width) sometimes seem very distorted.

There is no way to show the entire panorama (as a single photography) with all straight lines - straight. But...Here comes the cubic perspective:





As you can see - with cubic perspective:

• All lines are straight,
  
  
• The panorama is showed with 6 different square photos. They are called "cubefaces" (because they can be arranged to make a perfect 3D cube).

Cubic perspective is better suited for fullscreen panoramic players but there is no easy way to make them. For example, I used 4 different apps for the examples above: autostitch, Perl/erect2cubic command-line tool, GIMP and hugin.

Anybody interested in a quick tutorial on how to make cubic panoramas?