“Light transport simulation with vertex connection and merging”
Conference:
Type(s):
Title:
- Light transport simulation with vertex connection and merging
Session/Category Title: Global Illumination
Presenter(s)/Author(s):
Abstract:
Developing robust light transport simulation algorithms that are capable of dealing with arbitrary input scenes remains an elusive challenge. Although efficient global illumination algorithms exist, an acceptable approximation error in a reasonable amount of time is usually only achieved for specific types of input scenes. To address this problem, we present a reformulation of photon mapping as a bidirectional path sampling technique for Monte Carlo light transport simulation. The benefit of our new formulation is twofold. First, it makes it possible, for the first time, to explain in a formal manner the relative efficiency of photon mapping and bidirectional path tracing, which have so far been considered conceptually incompatible solutions to the light transport problem. Second, it allows for a seamless integration of the two methods into a more robust combined rendering algorithm via multiple importance sampling. A progressive version of this algorithm is consistent and efficiently handles a wide variety of lighting conditions, ranging from direct illumination, diffuse and glossy inter-reflections, to specular-diffuse-specular light transport. Our analysis shows that this algorithm inherits the high asymptotic performance from bidirectional path tracing for most light path types, while benefiting from the efficiency of photon mapping for specular-diffuse-specular lighting effects.
References:
1. Bekaert, P., Slussalek, P., Cools, R., Havran, V., and Seidel, H.-P. 2003. A custom designed density estimator for light transport. Tech. rep., Max-Planck-Institut für Informatik.
2. Davidovič, T., Křivánek, J., Hašan, M., Slusallek, P., and Bala, K. 2010. Combining global and local virtual lights for detailed glossy illumination. ACM Trans. Graph. 29, 6 (Dec.).
3. Dutré, P., Lafortune, E. P., and Willems, Y. 1993. Monte Carlo light tracing with direct computation of pixel intensities. In Compugraphics ’93, 128–137.
4. Fan, S., Chenney, S., and chi Lai, Y. 2005. Metropolis photon sampling with optional user guidance. In Eurographics Symposium on Rendering, Eurographics Association, 127–138.
5. Georgiev, I., Křivánek, J., and Slusallek, P. 2011. Bidirectional light transport with vertex merging. In SIGGRAPH Asia 2011 Sketches, ACM, New York, NY, USA, 27:1–27:2.
6. Hachisuka, T., and Jensen, H. W. 2009. Stochastic progressive photon mapping. ACM Trans. Graph. 28, 5 (Dec.), 141:1–141:8.
7. Hachisuka, T., and Jensen, H. W. 2011. Robust adaptive photon tracing using photon path visibility. ACM Trans. Graph. 30 (October), 114:1–114:11.
8. Hachisuka, T., Ogaki, S., and Jensen, H. W. 2008. Progressive photon mapping. ACM Trans. Graph. 27, 5 (Dec.).
9. Hachisuka, T., Jarosz, W., and Jensen, H. W. 2010. A progressive error estimation framework for photon density estimation. ACM Trans. Graph. 29, 6 (Dec.), 144:1–144:12.
10. Hachisuka, T., Pantaleoni, J., and Jensen, H. W. 2012. A path space extension for robust light transport simulation. ACM Trans. Graph. 31 (December).
11. Hašan, M., Pellacini, F., and Bala, K. 2007. Matrix row-column sampling for the many-light problem. ACM Trans. Graph. 26, 3 (July).
12. Hašan, M., Křivánek, J., Walter, B., and Bala, K. 2009. Virtual spherical lights for many-light rendering of glossy scenes. ACM Trans. Graph. 28, 5 (Dec.), 143:1–143:6.
13. Jakob, W., and Marschner, S. 2012. Manifold exploration: A Markov chain Monte Carlo technique for rendering scenes with difficult specular transport. ACM Trans. Graph. 31, 4.
14. Jensen, H. W. 2001. Realistic Image Synthesis Using Photon Mapping. A. K. Peters, Ltd., Natick, MA, USA.
15. Kajiya, J. 1986. The rendering equation. SIGGRAPH ’86.
16. Keller, A. 1997. Instant radiosity. In SIGGRAPH ’97, 49–56.
17. Knaus, C., and Zwicker, M. 2011. Progressive photon mapping: A probabilistic approach. ACM Trans. Graph. 30 (May).
18. Kollig, T., and Keller, A. 2000. Efficient bidirectional path tracing by randomized quasi-monte carlo integration. In MCQMC Methods 2000, 290–305.
19. Kollig, T., and Keller, A. 2004. Illumination in the presence of weak singularities. In MCQMC Methods 2004.
20. Křivánek, J., Ferwerda, J. A., and Bala, K. 2010. Effects of global illumination approximations on material appearance. ACM Trans. Graph. 29, 4 (July), 112:1–112:10.
21. Lafortune, E., and Willems, Y. D. 1993. Bi-directional path tracing. In Compugraphics ’93, 145–153.
22. Ou, J., and Pellacini, F. 2011. Lightslice: matrix slice sampling for the many-lights problem. ACM Trans. Graph. 30, 6 (Dec.).
23. Tokuyoshi, Y. 2009. Photon density estimation using multiple importance sampling. In SIGGRAPH Asia 2009 Posters.
24. Veach, E., and Guibas, L. 1994. Bidirectional estimators for light transport. In Eurographics Workshop on Rendering.
25. Veach, E., and Guibas, L. 1995. Optimally combining sampling techniques for Monte Carlo rendering. In SIGGRAPH ’95.
26. Veach, E., and Guibas, L. J. 1997. Metropolis light transport. In SIGGRAPH ’97.
27. Veach, E. 1997. Robust Monte Carlo Methods for Light Transport Simulation. PhD thesis, Standford Univeristy.
28. Vorba, J. 2011. Bidirectional photon mapping. In Proc. of the Central European Seminar on Computer Graphics (CESCG ’11).
29. Walter, B., Arbree, A., Bala, K., and Greenberg, D. P. 2006. Multidimensional lightcuts. ACM Trans. Graph. 25, 3.
30. Walter, B., Khungurn, P., and Bala, K. 2012. Bidirectional lightcuts. ACM Trans. Graph. 31, 4 (July), 59:1–59:11.
