Nap-of-earth flight and the real-time simulation of dynamic terrain

This document reports the results of the authors' work on understanding the problems associated with dynamic terrain (DT) in networked visual training simulators. Dynamic terrain (construction of emplacements, cratering and repair, etc.) is of substantial military interest as ground-based simulation becomes a common training technology. The basic cost/performance issues of visual simulation are analyzed with regard to the introduction of DT. An overview of current networking (SIMNET) technology for visual simulation is provided, and the difficulty of extending the SIMNET paradigm to dynamic terrain is discussed. An object-oriented representation for terrain is suggested, and its advantages are described. Finally, we consider the implications of dynamic terrain within networked simulation, with particular reference to the problems of scale imposed by the interaction of high speed aircraft flying nap-of-earth (i.e. at treetop level) and low speed ground vehicle simulators.