This article presents two classes and a set of utility functions for computational geometry. C3Point is a 3D counterpart to CPoint and CPolygon encapsulates a set of C3Point s and provides general polygon handling functions. The classes have been mildly optimised for speed. The classes were originally written for use in discretising 2D surfaces into element networks and for calculating properties of the resultant elements. Care must be taken when using some of the functions such as the curvature and area functions to ensure that the results returned by the functions are consistent with your needs and definitions.