This Article 
   
 Share 
   
 Bibliographic References 
   
 Add to: 
 
Digg
Furl
Spurl
Blink
Simpy
Google
Del.icio.us
Y!MyWeb
 
 Search 
   
VisibilityCluster: Average Directional Visibility for Many-Light Rendering
Sept. 2013 (vol. 19 no. 9)
pp. 1566-1578
Yu-Ting Wu, Dept. of Comput. Sci. & Inf. Eng., Nat. Taiwan Univ., Taipei, Taiwan
Yung-Yu Chuang, Dept. of Comput. Sci. & Inf. Eng., Nat. Taiwan Univ., Taipei, Taiwan
This paper proposes the VisibilityCluster algorithm for efficient visibility approximation and representation in many-light rendering. By carefully clustering lights and shading points, we can construct a visibility matrix that exhibits good local structures due to visibility coherence of nearby lights and shading points. Average visibility can be efficiently estimated by exploiting the sparse structure of the matrix and shooting only few shadow rays between clusters. Moreover, we can use the estimated average visibility as a quality measure for visibility estimation, enabling us to locally refine VisibilityClusters with large visibility variance for improving accuracy. We demonstrate that, with the proposed method, visibility can be incorporated into importance sampling at a reasonable cost for the many-light problem, significantly reducing variance in Monte Carlo rendering. In addition, the proposed method can be used to increase realism of local shading by adding directional occlusion effects. Experiments show that the proposed technique outperforms state-of-the-art importance sampling algorithms, and successfully enhances the preview quality for lighting design.
Index Terms:
Monte Carlo methods,Lighting,Rendering (computer graphics),Approximation methods,Approximation algorithms,Coherence,Geometry,the many-light problem,Ray tracing,visibility approximation,importance sampling
Citation:
Yu-Ting Wu, Yung-Yu Chuang, "VisibilityCluster: Average Directional Visibility for Many-Light Rendering," IEEE Transactions on Visualization and Computer Graphics, vol. 19, no. 9, pp. 1566-1578, Sept. 2013, doi:10.1109/TVCG.2013.21
Usage of this product signifies your acceptance of the Terms of Use.