Fast Walkthroughs with Image Caches and Ray Casting
We present an output-sensitive rendering algorithm for accelerating walkthroughs of large, densely occluded virtual environments using a multistage Image Based Rendering Pipeline. In the first stage, objects within a certain distance are rendered using the traditional graphics pipeline, whereas the remaining scene is rendered by a pixel-based approach using an Image Cache, horizon estimation to avoid calculating sky pixels, and finally, ray casting. The time complexity of this approach does not depend on the total number of primitives in the scene. We have measured speedups of up to one order of magnitude.
KeywordsComputer Graphic Virtual Environment Graphic Hardware Virtual City IEEE Computer Graphic
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- 1.D. G. Aliaga, A. A. Lastra. Architectural Walkthroughs Using Portal Textures. IEEE Visualization ‘87, pp. 355–362, November 1997.Google Scholar
- 2.J. Amanatides, A. Woo. A fast voxel traversal algorithm for ray tracing. Eurographics ‘87, pp. 3–10, North-Holland, August 1987.Google Scholar
- 3.B. Chamberlain et al. Fast rendering of complex environments using a spatial hierarchy. Graphics Interface ‘86, pp. 132–141, May 1996.Google Scholar
- 4.S. E. Chen. QuickTime VR - An Image-Based Approach to Virtual Environment Navigation. Computer Graphics (Proc. SIGGRAPH’95), pp. 29–38, 1995.Google Scholar
- 8.Hierarchical Z-Buffer Visibility. Computer Graphics (Proc. SIGGARPH’93), 27, pp. 231–238, 1993.Google Scholar
- 9.P. Heckbert, M. Garland. Survey of Polygonal Surface Simplification Algorithms. Technical Report, CS Dept., Carnegie Mellon U., to appear (draft May’97) (http://www.cs.cmu.edu/~ph/).
- 10.M. Kilgard. Realizing OpenGL: Two Implementations of One Architecture. 1997 SIGGRAPH/Eurographics Workshop on Graphics Hardware, pp. 45–56, August 1997Google Scholar
- 12.D. Luebke, Chris Georges. Portals and Mirrors: Simple, Fast Evaluation of Potentially Visible Sets. Proc. Symp. Interactive 3-D Graphics, ACM Press, April 1995.Google Scholar
- 13.L. McMillan, G. Bishop. Plenoptic Modeling: An Image-Based Rendering System. Computer Graphics (Proc. SIGGRAPH’95), 29, pp. 39–46, 1995.Google Scholar
- 14.M. Ohta, M. Maekawa. Ray Coherence Theorem and Constant Time Ray Tracing Algorithm. Computer Graphics 1987 (Proceedings of CG International ‘87), pp. 303–314, Springer-Verlag, 1987.Google Scholar
- 15.M. Rafferty, D. Aliaga, A. Lastra. 3D Image Warping in Architectural Walkthroughs IEEE Virtual Reality Annual International Symposium ‘88 (Atlanta, GA, 14–18 March 1998), 228–233Google Scholar
- 16.G. Schaufler, W. Stürzlinger. A Three-Dimensional Image Cache for Virtual Reality. Computer Graphics Forum (Proc. EUROGRAPHICS’96), 15(3), p. C227–C235, C471--C472, September 1996.Google Scholar
- 17.J. Shade et al. Hierarchical Image Caching for Accelerated Walkthroughs of Complex Environments. Computer Graphics (Proc. SIGGRAPH’96), 30, pp. 75–82, 1996.Google Scholar
- 18.J. Shade et al. Layered Depth Images. Computer Graphics (Proc. SIGGRAPH 98), pp. 231–242, July 1998.Google Scholar
- 19.Output-Sensitive Visibility Algorithms for Dynamic Scenes with Applications to Virtual Reality. Computer Graphics Forum, 15(3), pp. 249–258, Blackwell Publishers, August 1996.Google Scholar
- 21.Talisman: Commodity Real-time 3D Graphics for the PC. Computer Graphics (Proc. SIGGRAPH 96), pp. 353–364, August 1996.Google Scholar
- 22.H. Zhang et al. Visibility Culling Using Hierarchical Occlusion Maps. Computer Graphics (Proc. SIGGRAPH’97), 31(3A), pp. 77–88, August 1997.Google Scholar