Cross Hole
By Roger Bagula
Graphics by
Paul Bourke
January 2004
x = cos(u) / (R tan(v))
y = cos(2 u) / R
z = sin(2 u) / R
Where
R = cos
2
(u) cos
2
(v) + sin
2
(v)
and
0 <= u <= pi, 0 < v < pi
