Interactive Indirect Illumination Using Voxel Cone Tracing

Computer Graphics Forum (Proceedings of Pacific Graphics 2011), Volume 30, Number 7 - sep 2011
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Indirect illumination is an important element for realistic image synthesis, but its computation is expensive and highly dependent on the complexity of the scene and of the BRDF of the involved surfaces. While off-line computation and pre-baking can be acceptable for some cases, many applications (games, simulators, etc.) require real-time or interactive approaches to evaluate indirect illumination. We present a novel algorithm to compute indirect lighting in real-time that avoids costly precomputation steps and is not restricted to low-frequency illumination. It is based on a hierarchical voxel octree representation generated and updated on the ?y from a regular scene mesh coupled with an approximate voxel cone tracing that allows for a fast estimation of the visibility and incoming energy. Our approach can manage two light bounces for both Lambertian and glossy materials at interactive framerates (25-70FPS). It exhibits an almost scene-independent performance and can handle complex scenes with dynamic content thanks to an interactive octree-voxelization scheme. In addition, we demonstrate that our voxel cone tracing can be used to efficiently estimate Ambient Occlusion.

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Interactive Indirect Illumination and Ambient Occlusion Using Voxel Cone Tracing @Icare3D

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BibTex references

  author       = "Crassin, Cyril and Neyret, Fabrice and Sainz, Miguel and Green, Simon and Eisemann, Elmar",
  title        = "Interactive Indirect Illumination Using Voxel Cone Tracing",
  journal      = "Computer Graphics Forum (Proceedings of Pacific Graphics 2011)",
  number       = "7",
  volume       = "30",
  month        = "sep",
  year         = "2011",
  keywords     = "Global illumination, indirect lighting, ambient occlusion, final gather, cone-tracing, voxels, GPU, real-time rendering",
  url          = ""

Other publications in the database

» Cyril Crassin
» Fabrice Neyret
» Miguel Sainz
» Simon Green
» Elmar Eisemann