Efficient Radiosity Methods for Non-Separable Reflectance Models

  • Lazlo Neumann
  • Attila Neumann
Part of the EurographicSeminars book series (FOCUS COMPUTER)


Determination of interreflection of non-diffuse environments looks back to a few years. In case of N patches, separable (or, in particular, diffuse) reflectance leads to an equation system of N unknowns; in case of general bidirectional reflectance there are O(N 2) unknowns. This paper will describe two new, efficient methods for this latter extended, sparse matrix problem. Applying decomposition to diffuse + specular, sorted gathering + shooting methods is rather effective in case of small specular cones. The other method, relying on albedo-equivalent separable reflectance, offers a fast approximating radiosity solution, primarity suiting specular reflectances, with flat, undistinctive characteristics, for that any method is too slow. The two methods may be combined, the error term for the iterative solution of the first method defines a problem, offered a rapid approximate solution by the second method.


Conjugated Gradient Method Separable Model Bidirectional Reflectance Jacobi Iteration Albedo Function 
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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  1. [1]
    M. F. Cohen, D. P. Greenberg, D. D. Immel, and P. J. Brock. An efficient radiosity approach for realistic image synthesis. IEEE Computer Graphics and Applications, 6: 26–35, March 1986.CrossRefGoogle Scholar
  2. [2]
    Michael F. Cohen, Shenchang E. Chen, John R. Wallace, and Donald P. Greenberg. A progessive refinement approach to fast radiosity image generation. In SIGGRAPH’88 Conference Proceeding,pages 75–84, august 1988. Computer Graphics vol.22 num.4.Google Scholar
  3. [3]
    D. S. Immel, M. F. Cohen, and D. P. Greenberg. A radiosity method for non-diffused environments. Computer Graphics, 20 (4): 133–142, July 1986.CrossRefGoogle Scholar
  4. [4]
    J.T. Kajiya. The rendering equation. In Proceedings of SIGGRAPH’86 in computer graphics, pages 143–150, SIGGRAPH, August 1987.Google Scholar
  5. [5]
    Lhszló Neumann and Attila Neumann. Hybrid methods in photosimulation. Submitted to ACM TOG, 21–34, June 1989.Google Scholar
  6. [6]
    L£szló Neumann and Attila Neumann. Photosimulation: interreflection with arbitrary reflectance models and illumination. Computer Graphics Forum, 8 (1): 21–34, 1989.CrossRefGoogle Scholar
  7. [7]
    M. Shao, Q. Peng, and Y. Liang. A new radiosity approach by procedural refinements for realistic image synthesis. In SIGGRAPH’88 Conference Proceeding, pages 93–101, ACM, August 1988.Google Scholar
  8. [8]
    F. Sillion and C. Puech. A general two-pass method integrating specular and diffuse reflection. Computer Graphics, 23 (3): 335–344, July 1989.Google Scholar
  9. [9]
    J. R. Wallace, M. F. Cohen, and D. P. Greenberg. A two-pass solution to the rendering equation: a synthesis of ray tracing and radiosity methods. In SIGGRAPH’87 Conference Proceeding, pages 311320, ACM, August 1987.Google Scholar
  10. [10]
    G. Wyszecky and W. S. Stiles. Color Science, Concepts and Methods, Quantitative Datas and Formulas. J. Willey and sons, 2nd Edition, 1982.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • Lazlo Neumann
    • 1
  • Attila Neumann
    • 2
  1. 1.Oktatrend LtdBudapestHungary
  2. 2.Railway Research InstituteBudapestHungary

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