A class of surfaces for computer display

This paper describes the mathematical formulation of a class of three-dimensional surfaces parametrically represented for efficient computer display. The degrees of freedom in the representation are such as to provide a rich variety of surfaces with convenient parameters for manipulation and constraint satisfaction. Historically this work began as an investigation of the properties of rational parametric cubics, a class of curves well-suited to the Harvard three-dimensional display. The desire to represent curvilinear surfaces in terms of these curves and an introduction to the Coons' surface formulation were sufficient to suggest the approach discussed here.