The Community for Technology Leaders
RSS Icon
Subscribe
Issue No.05 - May (1987 vol.7)
pp: 14-20
Jeffrey Goldsmith , Jet Propulsion Laboratory
ABSTRACT
Intersection calculations dominate the run time of canonical ray tracers. A common algorithm to reduce the number of intersection tests required is the intersection of rays with a tree of extents, rather than the whole database of objects. A shortcoming of this method is that these trees are difficult to generate. Additionally, manually generated trees can be poor, greatly reducing the run-time improvement available. We present methods for evaluation of these trees in approximate number of intersection calculations required and for automatic generation of good trees. These methods run in O(nlogn) expected time where n is the number of objects in the scene. We report some examples of speedups.
INDEX TERMS
null
CITATION
Jeffrey Goldsmith, "Automatic Creation of Object Hierarchies for Ray Tracing", IEEE Computer Graphics and Applications, vol.7, no. 5, pp. 14-20, May 1987, doi:10.1109/MCG.1987.276983
REFERENCES
1. A.Appel, "Some Techniques for Machine Renderings of Solids," AFIPS Conf. Proc. 1968pp. 37-45 SJCC, AFIPS, Reston, Va.
2. J.Kajiya, "State of the Art in Image Synthesis," Computer Graphics (Proc. SIGGRAPH 83) July 1983 Tutorial on Ray Tracing (seminar notes)
3. T.Whitted, "An Improved Illumination Model for Shaded Display,"pp. 343-349 1980 Comm. ACM
4. L.V.Warren, "Geometric Hashing for Processing Complex Scenes," , CSDept. Memorandum, Univ. of Utah 1985
5. A.Glassner, IEEE CG&A , Oct. 1984pp. 15-22
6. S.Rubin and T.Whitted, "A 3-Dimensional Representation for Fast Rendering of Complex Scenes," Computer Graphics (Proc. SIGGRAPH 80) July 1980pp. 110-116
7. A.Fujimoto, IEEE CG&A , April 1986pp. 16-26
8. M.Kaplan, "Space-Tracing, a Constant Time Ray-Tracer," Computer Graphics (Proc. SIGGRAPH 85) July 1985 seminar notes from "State of the Art in Image Synthesis,"
9. G.Fox and S.Otto, "Algorithms for Concurrent Processors,"pp. 50-59 May 1984 Physics Today
10. D.Knuth, The Art of Computer Programming , Addison Wesley 1969 Vol. 2, pp. 139
11. T.Kay and J.Kajiya, "Ray Tracing Complex Scenes," Computer Graphics (Proc. SIGGRAPH 86) Aug. 1986pp. 169-278
12. H.Weghorst, G.Hooper, and D.Greenberg, "Improved Computational Methods for Ray Tracing,"pp. 52-69 Jan. 1984 ACM Trans. on Graphics
13. L.Stone, Theory of Optimal Search , Academic Press 1975pp. 27-28
14. J.Goldsmith and J.Salmon, Caltech Concurrent Computing Project Memorandum HM154 , Calif. Inst. Of Technology 1985
16 ms
(Ver 2.0)

Marketing Automation Platform Marketing Automation Tool