Abstract: This paper presents a real-time global illumination computation method.One-bound indirect illumination can be computed by this method in dynamic light source and dynamic view point environment，and the materials of object surface can be modified in real-time.This method pre-computes the form factor of all faces to solve the occlusion problem and records some importance faces with larger form factor as indirect light sources.During the real-time rendering，the method generates an extend shadow map of the scene through the direction of light source，which records the id and flux of the faces，and then computes indirect illumination from the sampled indirect light sources.The whole indirect illumination computation is implemented in GPU using CUDA，so this method can render the static scene in real-time and reach the realistic result.

Key words: importance faces sampling, global illumination, occlusion, Graphic Processing Unit（GPU）, Compute Unified Device Architecture（CUDA）

摘要： 提出了一种实时全局光照的计算方法。该方法支持任意视点下动态光源的一次间接光照计算，并且物体表面材质可实时编辑，该算法预计算了各面片上的形状因子来解决遮挡问题，并记录形状因子较大的重要性面片作为间接光源。渲染时先从光源方向对场景记录了一个扩展的阴影图，包含了光源照射到的面片ID和其光通量，再根据采样好的间接光源来计算间接光照。使用CUDA，整个光照计算过程在GPU中完成，可以对静态场景进行实时渲染，并能达到逼真的渲染效果。

关键词: 重要性面片采样, 全局光照, 遮挡, 图形处理器, 统一计算架构