NECTAR: Simulation and Visualization in a 3D Collaborative Environment

For simulation and visualization in a 3D collaborative environment, an architecture called the Nanyang Experimental CollaboraTive ARchitecture (NECTAR) has been developed. The objective is to support multi-user collaboration in a virtual environment with an emphasis on cost-effectiveness and interoperability. The architecture is based on the modular decomposition of a virtual environment system into three basic components: the graphics engine, the user interaction engine, and the networking engine. The scene graph-based graphics engine, written in Java 3D, takes VRML models loaded through the NAnyang Vrml Elementary Loader (NAVEL), as input. For multi-user interaction, NECTAR calls for the Core Living Worlds (CoreLW) extension of VRML. Coupled with this content-level strategy, on the wire level, the Java Shared Data Toolkit (JSDT) is employed, to the benefits of monitored, multi-threaded, multi-sessioned and multi-channelled communication. Some thought has also been given to optimizing network communication. Lastly, the modular, loosely-coupled and layered architecture has been found to facilitate flexible incremental, component-wise development.