Generative 3D models

This paper proposes a novel, yet extremely compact shape representation method. Its main feature is that 3D shapes are represented in terms of functions instead of geometric primitives. Given a set of - typically only a few - specific parameters, the evaluation of such a function results in a model that is one instance of a general shape. Particularly important for the web context with client systems of widely varying rendering performance is the support of a semantic level-of-detail superior to any low-level polygon reduction scheme.The shape description language has the power of a full programming language, but it has an extremely simple syntax. It serves as a ***mesh creation/manipulation language'. It is designed to facilitate the composition of more complex modeling operations out of simpler ones. Thus, it allows to create high-level operators which evaluate to arbitrarily complex, parameterized shapes. The underlying low-level shape representation is a boundary representation mesh in combination with Catmull/Clark subdivision surfaces.