报告题目：Microflake distributions and global illumination in sparse voxel octrees(稀疏体素八叉树中的微湖分布和全局照明)

报告人：Nelson Max, Distinguished professor

(SIGGRAPHStevenCoonsAward杰出贡献奖获得者)

报告人单位：University of California, Davis, USA.

加州大学戴维斯分校

Lawrence Livermore National Laboratory

劳伦斯利弗莫尔国家实验室

报告时间：2024年10月28日（周一）下午13:30-15:00

会议地点：江浦校区崇德楼D416会议室

举办单位：电气工程与控制科学学院

报告人简介：Nelson Max received his PhD in Mathematics from Harvard University, and is a distinguished professor emeritus at the University of California, Davis,USA.

His research interests are in the areas of scientific visualization, computer animation, realistic computer graphics rendering, augmented reality, and interactive web visualizations. In visualization he works on molecular graphics, and volume and flow visualization, particularly on irregular finite element meshes.

He has rendered realistic lighting effects in clouds, trees, and water waves, and has produced numerous computer animations, shown at the annual ACM SIGGRAPH conferences, and in OMNIMAX at the Fujitu Pavilions at Expo ’85 in Tsukuba Japan, and Expo ’90 in Osaka Japan.

报告摘要：Scenes in computer animation can have extreme complexity, especially when high resolution objects are placed in the distance and occupy only a few pixels. A useful technique for level of detail in these cases is to use a sparse voxel octree containing both hard surfaces and a participating medium consisting of microflakes. In this talk I will discuss three different methods for approximating the distribution of normals of the microflakes, which is needed to compute extinction, inscattering of attenuated direct illumination, and multiple scattering in the participating medium. Specifically, they are (a)kmeans approximation withkweighted representatives, (b) expansion in spherical harmonics, and (c) the distribution of the normals of a specific ellipsoid. I will compare their image quality, data size, and computation time. Finally I will explain a method of efficiently computing position-dependent fully anisotropic multiple scattering for global illumination in such octree volumes.

审核人：薄翠梅