Chain models in computer simulation

This paper presents an extension of a previously-described framework for the specification and manipulation of models of systems. The original framework and its extension include a convenient application programming interface (API), and this paper describes examples of the use of this API in the context of graphical simulation. These examples include the simulation of objects whose definition involves torques, and a brief description of the simulation of air and smoke by means of a model involving particles moving in fluid. [Copyright &y& Elsevier]