PAC-C3D: A New Software Architectural Model for Designing 3D Collaborative Virtual Environments

We propose PAC-C3D as a new software model for 3D Collaborative Virtual Environments (CVE). This model merges the results from two research fields: distribution models for CVE and HCI design for computer-supported cooperative work. PAC-C3D proposes to describe each part of a shared virtual object through explicit interfaces to ensure a strong separation between the core functions of a virtual environment, its (visual) representations, and its collaborative features such as synchronization and consistency maintenance between remote users. PAC-C3D makes it possible to design a CVE with low dependency between the core functions, the distribution mode and the 3D graphics API used. It explicitly deals with the main distribution modes encountered in CVE. It makes it easy to use different 3D graphics API for different nodes involved in the same collaborative session, providing interoperability between these 3D graphics API. It also makes it possible to integrate other kinds of 3D representations such as physics engines into the CVE.