Approach for software development of parallel real-time VE systems on heterogenous clusters

This paper presents our approach for the development of software for parallel real-time virtual environment systems (VE) running on heterogenous clusters of computers. This approach is based on a framework we have developed to facilitate the set-up of immersive virtual environment systems using single components coupled by an isolated local network. The framework provides parallel rendering of multiple projection screens and parallel execution of application and interaction tasks on components spread across a cluster. Main concept of the approach discussed in this paper is to use the virtual reality modeling language (VRML) as an interface definition language (IDL) for the parallel and distributed virtual environment system. An IDL-compiler generates skeleton-code for the implementations of the script nodes specified in a VRML-file. Components created this way can be reused in any VE by declaring the same interfaces. Instances of the implemented interfaces can reside in any application. By this approach commercial-of-the-shelf software can easily be integrated into a VE application. In this connection we discuss the underlying framework and software development process. Furthermore, the implementation of a VE system for a geographic information system (GIS) based on this approach is shown. It is emphasized that the components are used in various different applications.