The Visual Computer

, Volume 23, Issue 7, pp 493–502 | Cite as

Optimization techniques for curved path computing

  • Adolfo Muñoz
  • Diego Gutierrez
  • Francisco J. Serón
Original Article


Participating media with an inhomogeneous index of refraction make light follow curved paths. Simulating this in a global illumination environment has usually been neglected due to the complexity of the calculations involved, sacrificing accurate physical simulations for efficient visual results.

This paper aims to simulate non-linear media in a more reasonable time than previous works without losing physical correctness. Accuracy is achieved by solving the Eikonal equation of geometrical optics, which describes the path followed by a light beam that traverses a non-linear medium. This equation is used in the context of a photon mapping extension.

To improve the efficiency of the method, we study the existing correlation between numerical methods and the description of the non-linear medium, in terms of simulation time and error. Also, by taking advantage of several features of the scenes that include non-linear media, new optimization techniques that can be applied both for ray tracing and photon mapping will be developed. Flight or driving simulators could greatly benefit from this work.


Non-linear media Atmospheric phenomena Optimization 


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Adolfo Muñoz
    • 1
  • Diego Gutierrez
    • 1
  • Francisco J. Serón
    • 1
  1. 1.Grupo de Informatica Grafica Avanzada (GIGA)University of ZaragozaZaragozaSpain

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