OpenPING: A Reflective Middleware for the Construction of Adaptive Networked Game Applications

The emergence of distributed Virtual Reality (VR) applications that run over the Internet has presented networked game application designers with new challenges. In an environment where the public internet streams multimedia data and is constantly under pressure to deliver over widely heterogeneous user-platforms, there has been a growing need that distributed VR applications be aware of and adapt to frequent variations in their context of execution. In this paper, we argue that in contrast to research efforts targeted at improvement of scalability, persistence and responsiveness capabilities, much less attempts have been aimed at addressing the flexibility, maintainability and extensibility requirements in contemporary distributed VR platforms. We propose the use of structural reflection as an approach that not only addresses these requirements but also offers added value in the form of providing a framework for scalability, persistence and responsiveness that is itself flexible, maintainable and extensible. We also present an adaptive middleware platform implementation called OpenPING1 that supports our proposal in addressing these requirements

A multi-player educational game for story writing

In this short paper, a multi-player interactive game called STORYWORLD BUILDER is described. The game enables children to collaboratively build a virtual “story world” and then role-play characters in that world. The educational purpose of the system is to motivate children to write better stories, by providing them with a collaborative, interactive, computer game-like environment in which stories can be enacted. We are interested in whether such a system can improve children’s story writing skills

Analysis domain model for shared virtual environments

The field of shared virtual environments, which also encompasses online games and social 3D environments, has a system landscape consisting of multiple solutions that share great functional overlap. However, there is little system interoperability between the different solutions. A shared virtual environment has an associated problem domain that is highly complex raising difficult challenges to the development process, starting with the architectural design of the underlying system. This paper has two main contributions. The first contribution is a broad domain analysis of shared virtual environments, which enables developers to have a better understanding of the whole rather than the part(s). The second contribution is a reference domain model for discussing and describing solutions - the Analysis Domain Model

Enabling scalability by partitioning virtual environments using frontier sets

We present a class of partitioning scheme that we have called frontier sets. Frontier sets build on the notion of a potentially visible set (PVS). In a PVS, a world is subdivided into cells and for each cell all the other cells that can be seen are computed. In contrast, a frontier set considers pairs of cells, A and B. For each pair, it lists two sets of cells (two frontiers), FAB and FBA. By definition, from no cell in FAB is any cell in FBA visible and vice versa. Our initial use of frontier sets has been to enable scalability in distributed networking. This is possible because, for example, if at time t0 Player1 is in cell A and Player2 is in cell B, as long as they stay in their respective frontiers, they do not need to send update information to each other. In this paper we describe two strategies for building frontier sets. Both strategies are dynamic and compute frontiers only as necessary at runtime. The first is distance-based frontiers. This strategy requires precomputation of an enhanced potentially visible set. The second is greedy frontiers. This strategy is more expensive to compute at runtime, however it leads to larger and thus more efficient frontiers. Network simulations using code based on the Quake II engine show that frontiers have significant promise and may allow a new class of scalable peer-to-peer game infrastructures to emerge