中文摘要：

透明材料粗糙表面上多次方向透射可产生独特的视觉效果,但目前对其只能采用蒙特卡罗光线跟踪等离线方法绘制.为此提出一种实现该现象实时绘制的算法.通过将多次方向透射建模为一系列串行滤波器,得出一个多次方向透射的近似解;将该近似解用于预先计算遥远光源的多次方向透射,并将计算结果保存在一系列环境贴图中;这些环境贴图使GPU可以实时绘制透明材料粗糙表面的方向性折射和反射.实验结果表明,该算法在GPU上可以得到实现,并能够获得可信的绘制结果和满足交互应用的帧率.

英文摘要：

The directional transmissions at rough,transparent surfaces create a unique visual effect,which could only be rendered with offline methods such as Monte Carlo ray tracing.A rendering algorithm is proposed to achieve real-time rendering of this phenomenon.By treating the directional transmissions as serial filters,we propose an approximate solution for multiple consecutive directional transmissions;the approximate solution can be used to pre-calculate the transmitted distant lighting through multiple rough interfaces,and to store the results to a set of environment maps;by indexing these pre-calculated environment maps,GPU can render directional transmissions and reflections on rough,transparent surfaces in real time.Experimental results show that the proposed algorithm,which was implemented on a graphical hardware,was able to generate convincing rendering results and interactive frame rates.