Collaborative distributed virtual sculpting

A lot of effort is now being put into developing collaborative distributed virtual environments. However very few projects address collaborative virtual sculpting in which the shapes of the target objects are likely changing continuously. Some major issues including user interaction, data transmission, concurrent object editing by multiple clients and rendering of deforming objects must be addressed in a real-time context. We propose a framework for collaborative virtual sculpting in a distributed virtual environment. The system is based on a hybrid model which merges the client-server and the peer-to-peer architectures to allow fast data replication. To support real-time deformation and rendering of deformable objects, we model each of these objects using NURBS surfaces and render them using the real-time deformable NURBS rendering method that we have developed. We present a data structure for the transmission of these deformable objects. We also introduce the idea of editing region and the corresponding locking mechanism for simultaneous editing of the same object by multiple clients. Toward the end of the paper we show some performance results of the prototype system.

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