The Visual Computer

, Volume 26, Issue 6–8, pp 687–695 | Cite as

Volumetric ambient occlusion for volumetric models

  • Marc Ruiz
  • Lázló Szirmay-Kalos
  • Tamás Umenhoffer
  • Imma Boada
  • Miquel Feixas
  • Mateu Sbert
Original Article


This paper presents new algorithms to compute ambient occlusion for volumetric data. Ambient occlusion is used in video-games and film animation to mimic the indirect lighting of global illumination. We extend a novel interpretation of ambient occlusion to volumetric models that measures how big portion of the tangent sphere of a surface belongs to the set of occluded points, and propose statistically robust estimates for the ambient occlusion value. The data needed by this estimate can be obtained by separable filtering of the voxel array. As ambient occlusion is meant to obtain global illumination effects, it can provide decisive clues in interpreting the data. The new algorithms obtain smooth shading and can be computed at interactive rates, being thus appropriate for dynamic models exploration.


Ambient occlusion Obscurances Volume rendering 


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Marc Ruiz
    • 1
  • Lázló Szirmay-Kalos
    • 2
  • Tamás Umenhoffer
    • 2
  • Imma Boada
    • 1
  • Miquel Feixas
    • 1
  • Mateu Sbert
    • 1
  1. 1.Graphics and Imaging LaboratoryUniversitat de GironaGironaSpain
  2. 2.Budapest University of Technology and EconomicsBudapestHungary

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