Take a
circle K and a plane P, which is
perpendicular to the
plane that K lies on.
Now, take a second circle C with the same radius as K. Move C around, keeping its center on circle C and keeping it parallel to plane P. The surface sweeped out is a quartic surface called a Bohemian Dome. The following parametric equations define a Bohemian Dome:
x = a cos u
y = b cos v + a sin u
z = c sin v
where u, v ∈ [0, 2π).