Photon Splatting Using a View-Sample Cluster Hierarchy
Author
Editor
- Ulf Assarsson
- Warren Hunt
Summary, in English
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.
Department/s
Publishing year
2016
Language
English
Publication/Series
High-Performance Graphics 2016
Links
Document type
Conference paper
Publisher
Eurographics - European Association for Computer Graphics
Topic
- Computer Science
Conference name
High Performance Graphics, 2016
Conference date
2016-06-20 - 2016-06-22
Conference place
Dublin, Ireland
Status
Published
Project
- Empirical Heterogeneous System Modeling for Efficient Real-Time Rendering
Research group
- Computer Graphics
ISBN/ISSN/Other
- ISBN: 978-3-03868-008-6