基于锥形射线族投射的非直接光照算法  

Indirect Illumination Algorithm Based on Cone-rays Cast

作　　者：吴福祥[1] 董健康[2] 周付根[1] 

机构地区：[1]北京航空航天大学图像中心,北京100191 [2]中国民航大学航空自动化学院,天津300300

出　　处：《计算机工程》2013年第12期294-297,共4页Computer Engineering

摘　　要：在可交互应用中,基于射线投射的非直接光照采样数目常常受限。为此,考虑到空间关联,提出使用锥形射线族进行投射求交的算法,利用锥形边界预排除场景元素,并使用无堆栈算法在GPU中完成非直接光照计算,同时对算法使用的数据存储区域进行优化以达到更好的访问带宽,通过OpenCL和OpenGL实现该算法,结果证明该算法可以有效地计算非直接光照,相对于射线投射算法平均有2倍左右的性能提升。The indirect lighting calculations based on the ray-cast is a time-consuming process, therefore, the number of samples is limited in interactive program. Considered of spatial correlation, cone-ray cast algorithm is proposed to alleviate insufficient samples. It employs conical boundary to pre-exclude scene＇s elements, and implements in GPU as stack-less algorithm, additionally, optimizes storage location of the data to achieve the wider bandwidth, which is implemented by employ OpenGL and OpenCL. The result shows that the algorithm can efficiently compute indirect illumination, and brings about two-fold performance increase.

关 键 词：非直接光照 射线投射 锥形射线族 无堆栈算法 重要性采样 渲染方程 通用目的GPU计算 

分 类 号：TP301.6[自动化与计算机技术—计算机系统结构]