Gielis's Superformula for Complex Shapes
The superformula proposed by Gielis , a generalization of Piet Hein's superellipse, can be used to describe a wide range of forms, many of which are similar to natural structures.
In polar coordinates, the superformula can be represented by
 J. Gielis, "A Generic Geometric Transformation That Unifies a Wide Range of Natural and Abstract Shapes," American Journal of Botany, 90(3), 2003 pp. 333—338. doi:10.3732/ajb.90.3.333.
 Wikipedia. "Superformula." (Apr 28, 2020) en.wikipedia.org/wiki/Superformula.