NPSNET-IV: a real-time, 3D distributed interactive virtual world

Abstract

The problems addressed by this research are to develop a new NPSNET simulator to allow simulations with any simulator that complies with the Distributed Interactive Simulation (DIS) protocol; to provide a more realistic simulation by maximizing the use of the Silicon Graphics Inc. (SGI) Reality Engine; and to provide for future extensions to the system. The approach taken for this research was to develop a DIS based simulator. To provide greater realism, Performer, a 3-D toolkit made by SGI was used to take advantage of its multiprocessing management capabilities, real-time scene management, and other rapid rending tools. To enhance the systems extensibility, C++ object classes were used to encapsulate entity behaviors and user inputs. The result of this work is the NPSNET-IV simulation system. This system uses the DIS protocol to interact with other heterogeneously developed simulators as was demonstrated in a week long simulation between NPSNET-IV and two different simulation systems written by the Air Force Institute of Technology. Performer's direct access to the Reality Engine hardware and real-time scene management allows integration of more realistic models and higher rates of movement in the virtual world. The extensibility of the system is enhanced through the use of C++ objects, which was proven by the addition of a submersible vehicle type to the simulation.