Photon Splatting Using a View-Sample Cluster Hierarchy

Research output: Chapter in Book/Report/Conference proceedingPaper in conference proceeding


Splatting photons onto primary view samples, rather than gathering from a photon acceleration structure, can be a more efficient approach to evaluating the photon-density estimate in interactive applications, where the number of photons is often low compared to the number of view samples. Most photon splatting approaches struggle with large photon radii or high resolutions due to overdraw and insufficient culling. In this paper, we show how dynamic real-time diffuse interreflection can be achieved by using a full 3D acceleration structure built over the view samples and then splatting photons onto the view samples by traversing this data structure. Full dynamic lighting and scenes are possible by tracing and splatting photons, and rebuilding the acceleration structure every frame. We show that the number of view-sample/photon tests can be significantly reduced and suggest further culling techniques based on the normal cone of each node in the hierarchy. Finally, we present an approximate variant of our algorithm where photon traversal is stopped at a fixed level of our hierarchy, and the incoming radiance is accumulated per node and direction, rather than per view sample. This improves performance significantly with little visible degradation of quality.


External organisations
  • Chalmers University of Technology
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Computer Science
Original languageEnglish
Title of host publicationHigh-Performance Graphics 2016
EditorsUlf Assarsson, Warren Hunt
PublisherEurographics - European Association for Computer Graphics
Number of pages11
ISBN (Electronic)978-3-03868-008-6
Publication statusPublished - 2016
Publication categoryResearch
EventHigh Performance Graphics, 2016 - Trinity College, Dublin, Ireland
Duration: 2016 Jun 202016 Jun 22


ConferenceHigh Performance Graphics, 2016

Related projects

Pierre Moreau, Michael Doggett & Jacob Munkberg

Swedish Research Council


Project: DissertationIndividual research project

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Related activities

Moreau, P. (Presenter)
2016 Jun 22

Activity: Talk or presentationPresentation

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