Plot Function library for OpenSCAD, with Cartesian, Polar, and Axial coordinates

This is a general purpose function plotting library for OpenSCAD which will render functions with Cartesian coordinates (x & y input, z output), polar/cylindrical coordinates (r & angle input, z output), or axial coordinates (z & angle input, r output). This library is sufficiently flexible that it can be used for more than just plotting functions. As demonstrated in the included demo files, this can efficiently render ordinary objects with surfaces defined by mathematical functions.

While there are a few other function plotting libraries out there for OpenSCAD, this one is particularly robust, fast, and flexible. It uses list comprehension to generate each plot as a single polyhedron, supports multiple user-defined functions of each type in one design, consistently creates properly manifold renders, and executes as quickly as any other rendered object of comparable size.

Since OpenSCAD does not support passing functions as parameters, this library resolves it by allowing the