Abstract
The fundamental goal of virtual worlds is to provide users with the illusion that they are all seeing and interacting with each other in a consistent world. State melding is the core of creating this illusion of a shared reality. It includes two major parts: consistency maintenance and state update dissemination. Well-designed state melding technologies are also critical for developing a virtual world that can scale to a large number of concurrent users and provide satisfying user experiences. In this article, we present a taxonomy of consistency models and categorization of state update dissemination technologies for virtual worlds. To connect theories and practices, we then apply the taxonomy to case study several state-of-the-art virtual worlds. We also discuss challenges and promising solutions of state melding in large-scale virtual worlds. This survey aims to provide a thorough understanding of existing approaches and their strength and limitations and to assist in developing solutions to improve scalability and performance of virtual worlds.
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Index Terms
- Survey of state melding in virtual worlds
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