Implementation of a Distributed Interactive Graphics System

Abstract

The design, implementation, and performance of a distributed interactive graphics software system are described. The software is distributed between two machines with very different ca pabilities, a supercomputer (CRAY-2) and a graphics workstation (Silicon Graphics Iris). Both machines run the same operating system (UNIX) and are programmed by the user. Three-dimen sional graphical transformations, display updates, the user interface, and related operations are handled by the graphics workstation, while computationally intensive operations and some graphics are performed by the supercomputer. Three versions of this distributed graphics system are described; one builds display lists on the supercomputer, one builds them on the workstation, and one does not build them at all. Communication between the two machines con sists of a remote graphics protocol built on TCP/ IP. The performance of two distributed graphics programs—a test case and an application from computational fluid dynamics—is reported, and the timing results are analyzed.