Real-Time Aspects of VR Systems

Mathias Buhr, Thies Pfeiffer, Dirk Reiners, Carolina Cruz-Neira, Bernhard Jung

Abstract: The term real-time refers to the ability of computer systems to deliver results reliably within a predictable – usually as short as possible – time span. Real-time capability is one of the most difficult requirements for VR systems: users expect a VR system to let them experience the effects of interactions without noticeable delays. This chapter deals with selected topics concerning the real-time capability of VR systems. In the first section, an overall view of VR systems shows which types of latencies occur between user input and system reaction. It also discusses how latencies of the sub-components of VR systems can be estimated or measured. The second section presents common methods for efficient collision detection, such as the use of bounding volumes, which are important in real-time simulation of dynamic virtual worlds. The third section deals with real-time aspects when rendering virtual worlds.