The development of domain-specific virtual reality applications is often a slow and laborious process. The integration of the domain-specific functionality in an interactive Virtual Environment requires close collaboration between domain expert and VR developer, as well as the integration of domain-specific data and software in a VR application. The software environment needs to support the entire development process and software life cycle, from the early stages of iterative, rapid prototyping to a final end-user application. In this paper, we propose the use of flexible abstraction layers in the form of a dynamic scripting language, which act as the glue between VR system components and external software libraries and applications. First, we discuss the motivation and potential of our approach, after which we overview related approaches. Then, we describe the integration of a Python interpreter in our VR toolkit. The potential of our integration approach is demonstrated by rapid prototyping features, the flexible extension of core functionality and the integration of an external toolkit. We conclude with an overview of implications our approach has for the future development of new framework features and application integration

Abstract In projection‐based Virtual Reality (VR) systems, typically only one headtracked user views stereo images rendered from the correct view position. For other users, who are presented a distorted image, moving with the first user's head motion, it is difficult to correctly view and interact with 3D objects in the virtual environment. In close‐range VR systems, such as the Virtual Workbench, distortion effects are especially large because objects are within close range and users are relatively far apart. On these systems, multi‐user collaboration proves to be difficult. In this paper, we analyze the problem and describe a novel, easy to implement method to prevent and reduce image distortion and its negative effects on close‐range interaction task performance. First, our method combines a shared camera model and view distortion compensation. It minimizes the overall distortion for each user, while important user‐personal objects such as interaction cursors, rays and controls remain distortion‐free. Second, our method retains co‐location for interaction techniques to make interaction more consistent. We performed a user experiment on our Virtual Workbench to analyze user performance under distorted view conditions with and without the use of our method. Our findings demonstrate the negative impact of view distortion on task performance and the positive effect our method introduces. This indicates that our method can enhance the multi‐user collaboration experience on close‐range, projection‐based VR systems.

Abstract Implementation of stereo tiled displays is a rather demanding task. In this article we want to share the lessons we have learned during the design and construction of the ICWall tiled display. This large display, used in a classroom setting, is a high‐resolution stereo tiled display (2 × 8 tiles), built from low‐cost commodity components. The overall image is produced by an array of projectors. When building such a system, a key challenge is to align the projector images. We describe our automated approach for alignment/calibration of the left‐ and right‐eye stereo images. We provide measurements that show accuracy of this procedure. We explain and compare two calibration approaches: a single‐pass and a two‐pass rendering method to align the tiled images. We explain how to provide seamless image on the tiled display and which issues have to be solved. We also discuss the depth perception issues on the ICWall for the large audiences. Another important aspect, is the architecture of the software used for PC‐cluster‐based rendering. We describe Aura, the parallel scene graph API that is used for rendering on our tiled display. Copyright © 2007 John Wiley & Sons, Ltd.

This paper presents an approach to help speed up and unify the exploration and analysis of time-dependent, volumetric data sets by easily incorporating new qualitative and quantitative information into an exploratory virtual environment (VE). The new information is incorporated through one or more expedited offline "reprocessing" steps, which compute properties of objects extracted from the data. These objects and their properties are displayed in the exploratory VE. A case study involving atmospheric data is presented to demonstrate the utility of the method.

In this paper we present a basic set of intuitive exploration tools for the data visualization in a Virtual Environment on the Responsive Workbench. First, we introduce the Plexipad, a transparent acrylic panel which allows two-handed interaction in combination with a stylus. After a description of various interaction scenarios with these two devices, we present a basic set of interaction tools, which support the user in the process of exploring volumetric datasets. Besides the interaction tools for navigation and selection we present tools that are closely coupled with probing tools. These interactive probing tools are used as input for complex visualization tools and for performing virtual measurements. We illustrate the use of our tools in two applications from different research areas which use volumetric and particle data.