This code compares the fisheye projection with the conventional perspective projection by rendering an HDR cubemap.
Compared to the perspective projection, the fisheye projection is conformal, i.e., any 3D spherical objects remains spherical in screen space. It also behaves much better for wide field of views.
I got inspired to do this demo after seeing this cool quake mod: http://strlen.com/gfxengine/fisheyequake/
