Pages: pp. 2-3
Since 1994, the ACM Symposium on Virtual Reality Software and Technology (VRST) has continued to serve as one of the key forums for dissemination of the latest research results in virtual reality. It provides an opportunity for researchers in virtual reality and applications to interact with one another, share new results, and discuss emerging directions for the field. In 2008, VRST took place in Bordeaux, France. This special section contains the best three full papers of ACM VRST 2008, carefully selected by an international panel of leading authorities in virtual reality. Each full paper was initially reviewed by at least four to five members of the international program committee and external reviewers. The overall acceptance rate was 17 percent. Next, an international panel, consisting of Sabine Coquillart, Kiyoshi Kiyokawa, Ernst Kruijff, and Martin Hachet, judged the overall quality of the accepted symposium papers based on both the oral presentation and the exposition of these papers to be considered for the special section on ACM VRST 2008. The extended versions of these best papers from ACM VRST 2008 underwent more rounds of thorough review by additional experts in the process of publication in this special section of IEEE Transactions on Visualization and Computer Graphics ( TVCG). The papers cover some of the different topics addressed at VRST, from novel user interfaces for augmented reality (AR) to perceptual studies and new display architectures.
The first paper is directed toward the exploration of Normanistic values by looking at how real-world affordances can be used to control augmented reality applications. The paper, authored by Steven Henderson and Steven Feiner, is called "Opportunistic Tangible User Interfaces for Augmented Reality." Real-world objects around the user are mapped with values such as translation or rotation, by specifically looking at the affordances the objects communicate. Within the paper, the authors describe examples of controls that were designed and implemented using optical marker tracking, combined with appearance-based gesture recognition, and present several studies that demonstrate the advantages, but also the limits of the current approach. The power of the paper lies in its straightforwardness: Users can theoretically use any kind of object as interface, something many interface designers find highly desirable since it greatly adds to interaction "freedom." As such, the paper presents a fresh and valuable idea that provides AR interface development with new directions.
A problem many HMD users face is the offset between the size of the physical environment that can be moved through and the actual scale of the virtual environment itself. The second paper, "Estimation of Detection Thresholds for Redirected Walking Techniques," by Frank Steinicke, Gert Bruder, Jason Jerald, Harald Frenz, and Markus Lappe, tackles this problem by tricking human perception. The authors make use of the perceptual dominance of visual input over other modalities by redirecting the user over curved instead of straight paths, without the user actively noticing it. The premise of these mechanisms is that contradicting proprioceptive and vestibular cues are compensated for by quasi-correct visual cues that make the user believe she is actually traveling on a straight path. Within the paper, the authors present the results of a series of experiments in which they quantified how much humans can be redirected without observing inconsistencies. The authors present valuable results that can be used to optimize physical navigation techniques, relieving constraints of many HMD setups.
The third paper is entitled "A Programmable Display Layer for Virtual-Reality System Architectures." The authors of this contribution, Ferdi Smit, Robert van Liere, and Bernd Froehlich, show how to replace the default display behavior of standard VR applications to improve the interactive visual quality provided to the observers. Their architecture is based on a multi-GPU programmable display layer. They illustrate the benefit of their approach by highlighting the improvements they obtain for smooth motion during walk-throughs of large scenes, for average quality and consistency of latency reduction, and for quality of stereoscopic images. This work illustrates the latest advances in VR system architectures. The high-quality display that is obtained improves the user immersion for the new generation of VR applications.
We would like to thank the international panel, the members of the program committee, and the external reviewers for their insightful comments and thorough reviews. We would like to thank Thomas Ertl, the Editor-in-Chief of IEEE TVCG, for his support in having this special section. We hope that this special section will provide the readers enjoyable, stimulating, interesting, and thought provoking reading on some of the most exciting developments in the field of virtual reality.