基于重要性采样的三维云光照模型的研究  

Research of 3D Cloud Illumination Model Based on Importance Sampling

作　　者：谢永华[1,2] 袁复兴[1] 王畅[1] 

机构地区：[1]南京信息工程大学计算机与软件学院,南京210044 [2]南京信息工程大学江苏省网络监控中心,南京210044

出　　处：《系统仿真学报》2016年第1期57-62,69,共7页Journal of System Simulation

基　　金：国家自然科学基金资助项目(61375030);国家863计划项目(2011AA7123032B)

摘　　要：针对目前三维云的模拟过程中光照模型实现复杂、绘制效率低等问题,在多次前向散射光照模型的基础上提出了一种光照模型计算方法去解决光照模型中积分问题;针对多重散射光照模型中相位函数过于简单,不利于云的真实渲染的问题,优化现有相位函数,增强云的真实感。该方法通过对积分区间进行重要性采样解决光照积分计算过程中均匀采样效率过低的问题并结合两种相位函数实现了对云的渲染。实验结果表明:该方法在保证绘制质量的基础上提高了绘制速度,无论在效率上还是绘制效果上都更好地展示了云的物理特性,取得了很好的显示效果。Currently existing 3D cloud simulation illumination models were confronted with the shortcomings such as complexity of implementation and low rendering efficiency. Herein a calculation method for illumination model based on importance sampling was proposed; Aiming at the problems of the old phase function, a new phase function was proposed to improve the rendering efficiency and quality. By the design of the importance function, the method did importance sampling in integrated interval and combined two phase functions to render the cloud. The results of the simulation show that the presented method has enhanced the rendering speed with the guarantee of rendering quality. The result of the visualization can display the physical characters of the cloud both in rendering efficiency and quality, ensuring perfect visual effect.

关 键 词：光照模型 相位函数 重要性采样 多次散射 三维云渲染 

分 类 号：TP317.4[自动化与计算机技术—计算机软件与理论]