Realistic perspective projections for virtual objects and environments

Abstract

Computer graphics systems provide sophisticated means to render virtual 3D space to 2D display surfaces by applying planar geometric projections. In a realistic viewing condition the perspective applied for rendering should appropriately account for the viewer's location relative to the image. As a result, an observer would not be able to distinguish between a rendering of a virtual environment on a computer screen and a view “through” the screen at an identical real-world scene. Until now, little effort has been made to identify perspective projections which cause human observers to judge them to be realistic.

In this article we analyze observers' awareness of perspective distortions of virtual scenes displayed on a computer screen. These distortions warp the virtual scene and make it differ significantly from how the scene would look in reality. We describe psychophysical experiments that explore the subject's ability to discriminate between different perspective projections and identify projections that most closely match an equivalent real scene. We found that the field of view used for perspective rendering should match the actual visual angle of the display to provide users with a realistic view. However, we found that slight changes of the field of view in the range of 10-20% for two classes of test environments did not cause a distorted mental image of the observed models.

References

1. Ankrum, D. R. 1999. Visual ergonomics in the office: Guidelines. Occup. Health Safety 68, 7, 64--74.
2. Burdea, G. and Coiffet, P. 2003. Virtual Reality Technology. Wiley-IEEE Press.
3. Draper, M. H., Viirre, E. S., Furness, T. A., and Gawron, V. J. 2001. Effects of image scale and system time delay on simulator sickness within head-coupled virtual environments. J. Human Factors Ergonom. Soc. 43, 1, 129--146.
4. Ferwerda, J. 2008. SIGGRAPH core: Psychophysics 101: How to run perception experiments in computer graphics. In Proceedings of the International Conference on Computer Graphics and Interactive Techniques. ACM, SIGGRAPH 2008 classes.
5. Franke, I., Pannasch, S., Helmert, J. R., Rieger, R., Groh, R., and Velichkovsky, B. M. 2008. Towards attention-centered interfaces: An aesthetic evaluation of perspective with eye tracking. ACM Trans. Multimedia Comput. Comm. Appl. 4, 3, 1--13.
6. Gillam, B. 1980. Geometrical illusions. Amer. J. Science 242, 102--111.
7. Hagen, M. A. 1980. The Perception of pictures. (Series in Cognition and Perception). Academic Press.
8. Hendrix, C. and Barfield, W. 1996. Presence within virtual environments as a function of visual display parameters. Presence: Teleoper. Virtual Environ. 5, 3, 274--289.
9. Holloway, R. and Lastra, A., 1995. Virtual environments: A survey of the technology. Tech rep. TR93-033, University of North Carolina at Chapel Hill.
10. Kjelldahl, L. and Prime, M. 1995. A study on how depth perception is affected by different presentation methods of 3D objects on a 2D display. Computers Graph. 19, 2, 199--202.
11. Kuhl, S. A., Thompson, W. B., and Creem-Regehr, S. H. 2009. HMD calibration and its effects on distance judgments. ACM Trans. Appl. Percep. 6, 3, 1--19.
12. Loomis, J. M. and Knapp, J. M. 2003. Virtual and Adaptive Environments. Erlbaum, Mahwah, NJ. 21--46.
13. Loomis, J., Silva, J. D., Philbeck, J., and Fukusima, S. 1996. Visual perception of location and distance. Current Direct. Psych. Science 5, 72--77.
14. McGreevy, M., Ratzlaff, C., and Ellis, S. 1985. Virtual space and two-dimensional effects in perspective displays. In Proceedings of the 21st Annual Conference on Manual Control.
15. Messing, R. and Durgin, F. H. 2005. Distance perception and the visual horizon in head-mounted displays. ACM Trans. Appl. Percep. 2, 3, 234--250.
16. Murray, J. 1994. Some perspectives on visual depth perception. ACM SIGGRAPH Computer Graph., Special Issue on Interactive Entertainment Design, Implementation and Adrenaline. 28, 155--157.
17. Neale, D. C. 1996. Spatial perception in desktop virtual environments. In Proceedings of Human Factors and Ergonomics. 1117--1121.
18. Pirenne, M. H. 1970. Optics, Painting and Photography. Cambridge University Press, Cambridge, UK.
19. Polys, N., Kim, S., and Bowman, D. 2005. Effects of information layout, screen size, and field of view on user performance in information-rich virtual environments. In Proceedings of the Symposium on Virtual Reality and Software Systems (VRST). ACM, 46--55.
20. Rensink, R. A., O'Regan, J. K., and Clark, J. J. 1997. To see or not to see: The need for attention to perceive changes in scenes. Psych. Science 8, 5, 368--373.
21. Ries, B., Interrante, V., Kaeding, M., and Phillips, L. 2009. Analyzing the effect of a virtual avatar's geometric and motion fidelity on ego-centric spatial perception in immersive virtual environments. In Proceedings of the ACM Symposium on Virtual Reality Software and Technology (VRST). 59--66.
22. Rolland, J., Gibson, W., and Presence, D. A. 1995. Towards quantifying depth and size perception in virtual environments. Presence 4, 1, 24--48.
23. Rosenberg, C., and Barfield, W. 1995. Estimation of spatial distortion as a function of geometric parameters of perspective. IEEE Trans. Syst. Man Cybernetic 25, 1323--1333.
24. Shreiner, D. 2009. OpenGL Programming Guide: The official Guide to Learning OpenGL, Versions 3.0 and 3.1, 7th Ed. Addison-Wesley.
25. Steinicke, F., Bruder, G., Kuhl, S., Willemsen, P., Lappe, M., and Hinrichs, K. H. 2009. Judgment of natural perspective projections in head-mounted display environments. In Proceedings of the ACM Symposium on Virtual Reality Software and Technology (VRST). 35--42.
26. Stroebel, L. D. 1999. View Camera Technique. Focal Press.
27. Vishwanath, D., Girshick, A. R., and Banks, M. S. 2005. Why pictures look right when viewed from the wrong place? Nature Neurosci. 8, 1401--1410.
28. Warren, R., and Wertheim, A. H. 1990. Perception & Control of Self-Motion. Lawrence Erlbaum Associates, Mahwah, NJ.
29. Willemsen, P., Colton, M. B., Creem-Regehr, S., and Thompson, W. B. 2009. The effects of head-mounted display mechanical properties and field-of-view on distance judgments in virtual environments. ACM Trans. Appl. Percept. 2, 6.
30. Witmer, B. G., and Kline, P. B. 1998. Judging perceived and traversed distance in virtual environments. Presence: Teleoper. Virtual Environ. 7, 2, 144--167.
31. Zorin, D. and Barr, A. H. 1995. Correction of geometric perceptual distortions in pictures. In Proceedings of the 22nd Annual Conference on Computer Graphics and Interactive Techniques (SIGGRAPH), 257--264.

Index Terms

• Computing methodologies

  • Artificial intelligence

    • Computer vision

      • Image and video acquisition

        • 3D imaging

  • Computer graphics

    • Animation