“Compact precomputed voxelized shadows” by Sintorn, Kampe, Olsson and Assarsson

  • ©Erik Sintorn, Viktor Kampe, Ola Olsson, and Ulf Assarsson




    Compact precomputed voxelized shadows

Session/Category Title: Fast Rendering




    Producing high-quality shadows in large environments is an important and challenging problem for real-time applications such as games. We propose a novel data structure for precomputed shadows, which enables high-quality filtered shadows to be reconstructed for any point in the scene. We convert a high-resolution shadow map to a sparse voxel octree, where each node encodes light visibility for the corresponding voxel, and compress this tree by merging common subtrees. The resulting data structure can be many orders of magnitude smaller than the corresponding shadow map. We also show that it can be efficiently evaluated in real time with large filter kernels.


    1. Aila, T., and Laine, S. 2004. Alias-free shadow maps. In Proc. EG Symposium on Rendering 2004, EGSR’04, 161–166. Google ScholarDigital Library
    2. Annen, T., Mertens, T., Bekaert, P., Seidel, H.-P., and Kautz, J. 2007. Convolution shadow maps. In Proc. EG Symposium on Rendering 2007, EGSR’07, 51–60. Google ScholarDigital Library
    3. Annen, T., Mertens, T., Seidel, H.-P., Flerackers, E., and Kautz, J. 2008. Exponential shadow maps. In Proc. of Graph. Interface 2008, Canadian Information Proc. Soc., GI ’08, 155–161. Google ScholarDigital Library
    4. Arvo, J., and Hirvikorpi, M. 2005. Compressed shadow maps. Vis. Comput. 21, 3 (Apr.), 125–138. Google ScholarDigital Library
    5. Bunnel, M., and Pellacini, F. 2004. Shadow map antialiasing. In GPU Gems: Programming Techniques, Tips and Tricks for Real-Time Graphics, R. Fernando, Ed. Pearson Higher Education.Google Scholar
    6. Crow, F. C. 1977. Shadow algorithms for computer graphics. SIGGRAPH Comput. Graph. 11 (July), 242–248. Google ScholarDigital Library
    7. Donnelly, W., and Lauritzen, A. 2006. Variance shadow maps. In Proceedings of the 2006 Symposium on Interactive 3D Graphics and Games, ACM, I3D ’06, 161–165. Google ScholarDigital Library
    8. Eisemann, E., Schwarz, M., Assarsson, U., and Wimmer, M. 2011. Real-Time Shadows. A. K. Peters. Google ScholarDigital Library
    9. Engel, W. 2006. Cascaded shadow maps. In ShaderX5: Advanced Rendering Techniques, T. Forsyth, Ed., Shaderx series. Charles River Media, Inc.Google Scholar
    10. Everitt, C., 2001. Interactive order-independent transparency. Published online at http://www.nvidia.com/object/Interactive_Order_Transparency.html.Google Scholar
    11. Giegl, M., and Wimmer, M. 2007. Fitted virtual shadow maps. In Proceedings of Graphics Interface 2007, ACM, GI ’07, 159–168. Google ScholarDigital Library
    12. Green, C. 2007. Improved alpha-tested magnification for vector textures and special effects. In ACM SIGGRAPH 2007 Courses, ACM, SIGGRAPH ’07, 9–18. Google ScholarDigital Library
    13. Hasselgren, J., and Akenine-Möller, T. 2006. Efficient depth buffer compression. In Proc. 21st ACM SIGGRAPH/EG Symp. on Graphics Hardware, ACM, GH ’06, 103–110. Google ScholarDigital Library
    14. Heidmann, T. 1991. Real shadows, real time. Iris Universe 18, 28–31. Silicon Graphics, Inc.Google Scholar
    15. Johnson, G. S., Lee, J., Burns, C. A., and Mark, W. R. 2005. The irregular z-buffer: Hardware acceleration for irregular data structures. ACM Trans. Graph. 24, 4 (Oct.), 1462–1482. Google ScholarDigital Library
    16. Kämpe, V., Sintorn, E., and Assarsson, U. 2013. High resolution sparse voxel dags. ACM Trans. Graph. 32, 4 (July), 101:1–101:13. Google ScholarDigital Library
    17. Lefebvre, S., and Hoppe, H. 2007. Compressed random-access trees for spatially coherent data. In Proceedings of the 18th Eurographics Conference on Rendering Techniques, Eurographics Association, EGSR’07, 339–349. Google ScholarDigital Library
    18. Lefohn, A. E., Sengupta, S., and Owens, J. D. 2007. Resolution-matched shadow maps. ACM Trans. Graph. 26, 4 (Oct.). Google ScholarDigital Library
    19. Lloyd, D. B., Tuft, D., Yoon, S.-e., and Manocha, D. 2006. Warping and partitioning for low error shadow maps. In Proceedings of the 17th Eurographics Conference on Rendering Techniques, Eurographics Association, EGSR’06, 215–226. Google ScholarDigital Library
    20. Ramamoorthi, R. 2009. Precomputation-based rendering. Found. Trends. Comput. Graph. Vis. 3, 4 (Apr.), 281–369. Google ScholarDigital Library
    21. Rasmusson, J., Ström, J., Wennersten, P., Doggett, M., and Akenine-Möller, T. 2010. Texture compression of light maps using smooth profile functions. In Proceedings of the Conference on High Performance Graphics, HPG ’10, 143–152. Google ScholarDigital Library
    22. Sintorn, E., Eisemann, E., and Assarsson, U. 2008. Sample based visibility for soft shadows using alias-free shadow maps. In Proc. of 19th EG Conf. on Rendering, Eurographics Association, EGSR’08, 1285–1292. Google ScholarDigital Library
    23. Sintorn, E., Olsson, O., and Assarsson, U. 2011. An efficient alias-free shadow algorithm for opaque and transparent objects using per-triangle shadow volumes. ACM Trans. Graph. 30, 6 (Dec.), 153:1–153:10. Google ScholarDigital Library
    24. Williams, L. 1978. Casting curved shadows on curved surfaces. SIGGRAPH Comput. Graph. 12 (August), 270–274. Google ScholarDigital Library
    25. Woo, A., and Poulin, P. 2012. Shadow Algorithms Data Miner. Taylor & Francis.Google Scholar
    26. Zhang, F., Sun, H., and Nyman, O. 2005. Parallel-split shadow maps on programmable GPUs. In GPU Gems 3, Addison-Wesley, H. Nguyen, Ed.Google Scholar
    27. Zhang, F., Sun, H., Xu, L., and Lun, L. K. 2006. Parallel-split shadow maps for large-scale virtual environments. In Proc. Virtual Reality Continuum and Its Applications, ACM, VRCIA ’06, 311–318. Google ScholarDigital Library

ACM Digital Library Publication:

Overview Page: