Daniel Acevedo

The future of the CAVE

The CAVE, a walk-in virtual reality environment typically consisting of 4–6 3 m-by-3 m sides of a room made of rear-projected screens, was first conceived and built in 1991. In the nearly two decades since its conception, the supporting technology has improved so that current CAVEs are much brighter, at much higher resolution, and have dramatically improved graphics performance. However, rear-projection-based CAVEs typically must be housed in a 10 m-by-10 m-by-10 m room (allowing space behind the screen walls for the projectors), which limits their deployment to large spaces. The CAVE of the future will be made of tessellated panel displays, eliminating the projection distance, but the implementation of such displays is challenging. Early multi-tile, panel-based, virtual-reality displays have been designed, prototyped, and built for the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia by researchers at the University of California, San Diego, and the University of Illinois at Chicago. New means of image generation and control are considered key contributions to the future viability of the CAVE as a virtual-reality device.

Archaeological data visualization in VR: analysis of lamp finds at the great temple of petra, a case study

Presents the results of an evaluation of the ARCHAVE (ARCHAeological Virtual Environment) system, an immersive virtual reality (VR) environment for archaeological research. ARCHAVE is implemented in a Cave. The evaluation studied researchers analyzing lamp and coin finds throughout the excavation trenches at the Petra Great Temple site in Jordan. Experienced archaeologists used our system to study excavation data, confirming existing hypotheses and postulating new theories they had not been able to discover without the system. ARCHAVE provided access to the excavation database, and researchers were able to examine the data in the context of a life-size representation of the present-day architectural ruins of the temple. They also had access to a miniature model for site-wide analysis. Because users quickly became comfortable with the interface, they concentrated their efforts on examining the data being retrieved and displayed. The immersive VR visualization of the recovered information gave them the opportunity to explore it in a new and dynamic way and, in several cases, enabled them to make discoveries that opened new lines of investigation about the excavation.

Designer-critiqued comparison of 2D vector visualization methods: a pilot study

Figure 1. The six visualization methods the designer critiqued. The large image shows a full screen shot. The other six are details from each method (clockwise from top-left: JIT, LIC, LIT, OSTR, GRID, GSTR). The circles represent an advection task used in a previous study [Laidlaw et al. 2001]. Observers were asked to indicate where a particle in the flow, starting at the small concentric circle, would intersect the large concentric circle; the other circle represents the correct intersection point. GSTR JIT LIC LIT OSTR GRID

Subjective Quantification of Perceptual Interactions among some 2D Scientific Visualization Methods

We present an evaluation of a parameterized set of 2D icon-based visualization methods where we quantified how perceptual interactions among visual elements affect effective data exploration. During the experiment, subjects quantified three different design factors for each method: the spatial resolution it could represent, the number of data values it could display at each point, and the degree to which it is visually linear. The class of visualization methods includes Poisson-disk distributed icons where icon size, icon spacing, and icon brightness can be set to a constant or coupled to data values from a 2D scalar field. By only coupling one of those visual components to data, we measured filtering interference for all three design factors. Filtering interference characterizes how different levels of the constant visual elements affect the evaluation of the data-coupled element. Our novel experimental methodology allowed us to generalize this perceptual information, gathered using ad-hoc artificial datasets, onto quantitative rules for visualizing real scientific datasets. This work also provides a framework for evaluating visualizations of multi-valued data that incorporate additional visual cues, such as icon orientation or color

Color Rapid Prototyping for Diffusion-Tensor MRI Visualization

We describe work toward creating color rapid prototyping (RP) plaster models as visualization tools to support scientific research in diffusion-tensor (DT) MRI analysis. We currently give surgeons and neurologists virtual-reality (VR) applications to visualize different aspects of their brain data, but having physical representations of those virtual models allows them to review the data with a very robust, natural, and fast haptic interface: their own hands. Our initial results are encouraging, and end users are excited about the possibilities of this technique. For example, using these models in conjunction with digital models on the computer screen or VR environment provides a static frame of reference that helps keep users oriented during their analysis tasks.

Design-by-example: a schema for designing visualizations using examples from art

We present a design schema for generating data visualizations using examples from art. With this approach a user: 1.) chooses a composition or detail from a favorite painting, 2.) generates a template by extracting characteristics or brushstrokes suitable for representing data variables, 3.) generates a pre-visualization of the data using a rendering framework [Sobel 2003] and, 4.) transfers the features from the painting using the Image Analogies, Texture-By-Numbers algorithm [Hertzmann et al. 2001].