Bounding ellipsoids for ray-fractal intersection

ABSTRACT

Recently published papers have shown that, with appropriate intersection algorithms, the rendering of many procedural objects is possible with all the advantages offered by the ray-tracing techniques. In the case of stochastic surfaces, the intersection can be computed by a recursive subdivision technique. The efficiency of this algorithm depends essentially on the bounding volume whose size and shape are directly related to the stochastic characteristics of these surfaces. After a brief review of the rendering of stochastic surfaces and the bounding volume selection problem, two types of bounding volume are studied, describing how their intersection with a ray can be computed and how their size can be derived from the stochastic characteristics. The efficiency then, of these bounding volumes are compared.

REFERENCES

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.7 Three-Dimensional Graphics and Realism
          Subjects: Raytracing

Additional Classification:
  G. Mathematics of Computing
  G.3 PROBABILITY AND STATISTICS
      Subjects: Stochastic processes

  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
  I.4 IMAGE PROCESSING AND COMPUTER VISION
      I.4.5 Reconstruction
          Subjects: Transform methods

General Terms:
Algorithms, Design, Measurement, Performance, Theory