Sparsely Precomputing The Light Transport Matrix for Real-Time Rendering.

Saved in:

Bibliographic Details
Title:	Sparsely Precomputing The Light Transport Matrix for Real-Time Rendering.
Authors:	Fu-Chung Huang¹ jonash@cs.berkeley.edu, Ramamoorthi, Ravi¹ ravir@cs.berkeley.edu
Source:	Computer Graphics Forum. Jun2010, Vol. 29 Issue 4, p1335-1345. 11p. 11 Illustrations, 3 Diagrams, 5 Charts, 2 Graphs.
Subjects:	Real-time rendering (Computer graphics), Interactive computer graphics, Principal components analysis, Wavelets (Mathematics), Ray tracing algorithms, Rapid prototyping, Light transmission, Interpolation
Abstract:	Precomputation-based methods have enabled real-time rendering with natural illumination, all-frequency shadows, and global illumination. However, a major bottleneck is the precomputation time, that can take hours to days. While the final real-time data structures are typically heavily compressed with clustered principal component analysis and/or wavelets, a full light transport matrix still needs to be precomputed for a synthetic scene, often by exhaustive sampling and raytracing. This is expensive and makes rapid prototyping of new scenes prohibitive. In this paper, we show that the precomputation can be made much more efficient by adaptive and sparse sampling of light transport. We first select a small subset of “dense vertices”, where we sample the angular dimensions more completely (but still adaptively). The remaining “sparse vertices” require only a few angular samples, isolating features of the light transport. They can then be interpolated from nearby dense vertices using locally low rank approximations. We demonstrate sparse sampling and precomputation 5 × faster than previous methods. [ABSTRACT FROM AUTHOR]
	Copyright of Computer Graphics Forum is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database:	Engineering Source

Description
Abstract:	Precomputation-based methods have enabled real-time rendering with natural illumination, all-frequency shadows, and global illumination. However, a major bottleneck is the precomputation time, that can take hours to days. While the final real-time data structures are typically heavily compressed with clustered principal component analysis and/or wavelets, a full light transport matrix still needs to be precomputed for a synthetic scene, often by exhaustive sampling and raytracing. This is expensive and makes rapid prototyping of new scenes prohibitive. In this paper, we show that the precomputation can be made much more efficient by adaptive and sparse sampling of light transport. We first select a small subset of “dense vertices”, where we sample the angular dimensions more completely (but still adaptively). The remaining “sparse vertices” require only a few angular samples, isolating features of the light transport. They can then be interpolated from nearby dense vertices using locally low rank approximations. We demonstrate sparse sampling and precomputation 5 × faster than previous methods. [ABSTRACT FROM AUTHOR]
ISSN:	01677055
DOI:	10.1111/j.1467-8659.2010.01729.x