“Dual scattering approximation for fast multiple scattering in hair” by Zinke, Yuksel, Weber and Keyser

When rendering light colored hair, multiple fiber scattering is essential for the right perception of the overall hair color. In this context, we present a novel technique to efficiently approximate multiple fiber scattering for a full head of human hair or a similar fiber based geometry. In contrast to previous ad-hoc approaches, our method relies on the physically accurate concept of the Bidirectional Scattering Distribution Functions and gives physically plausible results with no need for parameter tweaking. We show that complex scattering effects can be approximated very well by using aggressive simplifications based on this theoretical model. When compared to unbiased Monte-Carlo path tracing, our approximations preserve photo-realism in most settings but with rendering times at least two-orders of magnitude lower. Time and space complexity are much lower compared to photon mapping-based techniques and we can even achieve realistic results in real-time on a standard PC with consumer graphics hardware.

1. Bertails, F., Ménier, C., and Cani, M.-P. 2005. A practical self-shadowing algorithm for interactive hair animation. In Graphics Interface, 71–78. Google ScholarDigital Library
2. Gupta, R., and Magnenat-Thalmann, N. 2005. Scattering-based interactive hair rendering. In Comp. Aided Design and Comp. Graphics, 489–496. Google ScholarDigital Library
3. Hadwiger, M., Kratz, A., Sigg, C., and Bühler, K. 2006. Gpu-accelerated deep shadow maps for direct volume rendering. In Proceedings of Graphics Hardware 2006, 49–52. Google ScholarDigital Library
4. Kim, T.-Y., and Neumann, U. 2001. Opacity shadow maps. In Eurographics Rendering Workshop, 177–182. Google ScholarDigital Library
5. Kniss, J., Premoze, S., Hansen, C., Shirly, P., and McPherson, A. 2003. A model for volume lighting and modeling. IEEE Trans. on Vis. and Comp. Graphics 9, 2, 150–162. Google ScholarDigital Library
6. Lokovic, T., and Veach, E. 2000. Deep shadow maps. In Proceedings of SIGGRAPH 2000, 385–392. Google ScholarDigital Library
7. Marschner, S. R., Jensen, H. W., Cammarano, M., Worley, S., and Hanrahan, P. 2003. Light scattering from human hair fibers. ACM Transactions on Graphics 22, 3, 780–791. SIGGRAPH 2003. Google ScholarDigital Library
8. Mertens, T., Kautz, J., Bekaert, P., and Reeth, F. V. 2004. A self-shadow algorithm for dynamic hair using density clustering. In Eurographics Symposium on Rendering, 173–178. Google ScholarCross Ref
9. Moon, J. T., and Marschner, S. R. 2006. Simulating multiple scattering in hair using a photon mapping approach. ACM Transactions on Graphics 25, 3, 1067–1074. SIGGRAPH 2006. Google ScholarDigital Library
10. Premoze, S., Ashikhmin, M., Ramamoorthi, R., and Nayar, S. 2004. Practical rendering of multiple scattering effects in participating media. In Eurographics Symp. on Rendering. Google ScholarCross Ref
11. Ward, K., Bertails, F., Kim, T.-Y., Marschner, S. R., Cani, M.-P., and Lin, M. 2007. A survey on hair modeling: Styling, simulation, and rendering. IEEE Transactions on Visualization and Computer Graphics 13, 2, 213–34. Google ScholarDigital Library
12. Xu, S., Lau, F. C., Jiang, H., and Pan, Y. 2006. A novel method for fast and high-quality rendering of hair. In Proc. of the 17th Eurographics Symp. on Rendering, 331–341, 440. Google ScholarCross Ref
13. Yuksel, C., and Keyser, J. 2008. Deep opacity maps. Computer Graphics Forum (Proc. of EUROGRAPHICS 2008) 27, 2.Google Scholar
14. Yuksel, C., Akleman, E., and Keyser, J. 2007. Practical global illumination for hair rendering. In Pacific Graphics 2007, 415–418. Google ScholarDigital Library
15. Zinke, A., and Weber, A. 2006. Global illumination for fiber based geometries. In Electronic proceedings of the Ibero American Symposium on Computer Graphics (SIACG 2006).Google Scholar
16. Zinke, A., and Weber, A. 2007. Light scattering from filaments. IEEE Trans. on Vis. and Comp. Graphics 13, 2, 342–356. Google ScholarDigital Library
17. Zinke, A., Sobottka, G., and Weber, A. 2004. Photorealistic rendering of blond hair. In Vision, Modeling, and Visualization (VMV) 2004, 191–198.Google Scholar