Mathematics by Roger L. Bagula
4 July 2000
Graphics by Paul Bourke
Appeared on stickers for the MAA
(Mathematical Association of America).
x = -2 r cos(p) + 2 cos(p) / r - 2 r3 cos(3 p) / 3
y = 6 r sin(p) - 2 sin(p) / r - 2 r3 sin(3 p) / 3
z = 4 log(r)
Where 0.5 <= r <= 1
and 0 <= p <= 2 pi
The source code creates polygonal facets in the "geom"
format. Most of the complexity comes from deriving colours and
normals at each vertex, of course this is necessary in order to
get a smooth surface with a limited polygonal representation.