cylinderical-egg-crate    vec(cos(u),sin(u),v) + (.05*sin(30*u)*cos(30*v)*vec(cos(u),sin(u),0))
spherical-grooves vec(cos(u)*sin(v),sin(u)*sin(v),cos(v))+(0.03*sin(30*u)*vec(-cos(u)*sin(v)*sin(v),cos(u)*cos(u)*sin(v)*cos(v)-sin(u)*sin(v)*sin(v),-sin(v)*cos(v)))