Pyramid Clipping for Efficient Ray Traversal

  • Maurice van der Zwaan
  • Erik Reinhard
  • Frederik W. Jansen
Part of the Eurographics book series (EUROGRAPH)


Rays having the same origin and similar directions frequently appear in the form of viewing rays and shadow rays to area light sources in ray tracing, and in hemisphere shooting or gathering in radiosity algorithms. The coherence between these rays can be exploited by enclosing a bundle of these rays with a pyramid and by classifying objects with respect to this pyramid prior to tracing the rays. We present an implementation of this algorithm for a bintree spatial subdivision structure and compare the performance with a recursive bintree traversal and the standard grid traversal algorithm. In parallel implementations the technique can be used to create coherent intersection tasks, allowing demand-driven scheduling with low communication overheads.


Exit Point Multi Grid Method Pyramid Plane Spatial Subdivision Hybrid Schedule 
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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Copyright information

© Springer-Verlag/Wien 1995

Authors and Affiliations

  • Maurice van der Zwaan
    • 1
  • Erik Reinhard
    • 1
  • Frederik W. Jansen
    • 1
  1. 1.Faculty of Technical Mathematics and InformaticsDelft University of TechnologyDelftThe Netherlands

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