The Visual Computer

, Volume 9, Issue 2, pp 91–104 | Cite as

Interval Ray Tracing — a divide and conquer strategy for realistic computer graphics

  • Wolfgang Enger


A new method for ray tracing parametric surfaces is developed. The method uses a divide-and-conquer strategy for rapid finding of the sectors of constant intensity. Techniques from interval analysis allow reducing the number of ray/surface intersections that must be computed. Main results are presented in terms of solving a general system of nonlinear equations, and thus can be extended to a large class of problems. Examples with B-spline surfaces demonstrate an improvement in computation time over a conventional method with a factor between 1.5 and 3.0. Additionally, a way of preventing “cracks” in triangulating parametric surfaces is shown.

Key words

Ray tracing Interval analysis Parametric surfaces B-splines Triangulation 


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Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • Wolfgang Enger
    • 1
  1. 1.Institut für Angewandte MathematikUniversität FreiburgFreiburgFederal Republic of Germany

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