An "equiangular surface"
as defined by K. Boyadzhiev
Reference: K. Boyadzhiev, Equiangular surfaces, self-similar surfaces, and the geometry of seashells, College Math. Journal (4) 38 (2007), 265 - 271.
Maple code:
![h := mu*(sqrt(a^2+1)*arctan(sqrt(a^2+1)*tan(psi)/sqrt(a^2-tan(psi)^2))-arctan(tan(psi)/sqrt(a^2-tan(psi)^2))); 1](images/equiang_2.gif)
> |
![rho1 := R*exp(mu*theta+h); 1](images/equiang_5.gif) |
POV-Ray picture:
(exported from Maple)