COVRA-CAD: A CORBA-based Distributed VR CAD System

Running a large and complex virtual environment may require certain computational services to be implemented in a distributed manner, especially those that are relatively less time-critical, considering the network delay. An important question, therefore, is the criteria for migrating computational processes oo the main graphics rendering workstation to optimize the performance per cost in the context of VR application development. In this paper, we introduce COVRA, a CORBA-based distributed VR Architecture being developed at POSTECH. CORBA allows applications to communicate with one another no matter where they are located or who has designed them. Our immediate goal is to build a multimodal virtual CAD system in which we regard CAD operations and each modal processing as services to be provided by computational units connected to the main graphics rendering workstation by a high speed network. We describe our experience in the system development process , highlighting the application of the decoupled simulation model originally proposed by 3], and the concept of viewing service as CORBA object methods. We also address the potential problem of the performance lag in using a distributed broker architecture in comparison to using direct low level communication, and to single server architectures, and comment on the criteria for distributing computational services in the context of VR software requirements.