Fisheye perspective is a two-part projection. First, three-dimensional space is projected onto the surface of a hemisphere,
by connecting every external point to the center of the sphere. Second, the hemisphere
is projected onto its underlying circle.
de Vries, V. Perspective. New York: Dover, 1968.Parramon, J. M. Perspective--How to Draw.
Barcelona, Spain: Parramon Editions, 1984.Steinhaus, H. Mathematical
Snapshots, 3rd ed. New York: Dover, pp. 157-159, 1999.
