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Employing Dynamic Transparency for 3D Occlusion Management: Design Issues and Evaluation

  • Niklas Elmqvist
  • Ulf Assarsson
  • Philippas Tsigas
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4662)

Abstract

Recent developments in occlusion management for 3D environments often involve the use of dynamic transparency, or virtual “X-ray vision”, to promote target discovery and access in complex 3D worlds. However, there are many different approaches to achieving this effect and their actual utility for the user has yet to be evaluated. Furthermore, the introduction of semi-transparent surfaces adds additional visual complexity that may actually have a negative impact on task performance. In this paper, we report on an empirical user study comparing dynamic transparency to standard viewpoint controls. Our implementation of the technique is an image-space algorithm built using modern programmable shaders to achieve real-time performance and visually pleasing results. Results from the user study indicate that dynamic transparency is superior for perceptual tasks in terms of both efficiency and correctness.

Keywords

Target Object Average Relative Error Graphic Hardware Occlude Object Counting Task 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© IFIP International Federation for Information Processing 2007

Authors and Affiliations

  • Niklas Elmqvist
    • 1
  • Ulf Assarsson
    • 1
  • Philippas Tsigas
    • 1
  1. 1.Department of Computer Science & Engineering, Chalmers University of Technology, SE-412 96 GöteborgSweden

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