考虑轮廓不透明和光照效果的改进透明混合方法  

Improved Transparency Blending Method for Silhouette-Opaque and Lighting Effect

作　　者：罗备[1] 罗月童[1] 杜涛[1] 

机构地区：[1]合肥工业大学计算机与信息学院VCC研究室,合肥230009

出　　处：《系统仿真学报》2012年第1期117-119,131,共4页Journal of System Simulation

基　　金：国家自然科学基金(11005028);安徽省基金(090412066);安徽省教育厅自然科学基金(KJ2009B043Z)

摘　　要：光线跟踪算法虽然能够逼真的渲染透明物体,但难以融入在交互式图形应用中广泛使用的固定图形流水线,因此发展能应用于固定图形流水线的透明渲染算法具有重要意义。Alpha混合方法在固定图形渲染流水线中被广泛用于渲染透明物体,但其渲染结果的真实感较弱。利用现代可编程GPU,动态调整alpha混合因子增强结果图像的真实感。alpha混合因子调整策略依据以下事实:根据透明物体轮廓的不透明性比中间区域大以及在含有光照的情况下光线直射的区域会更透明。方法已经应用于自主研发的"数字锂铅实验回路仿真系统",该系统存在大量的透明管道,取得了良好的透明效果。Although ray tracing can render transparent objects realistically, it is hard to be integrated into the fixed graphic pipeline, which has been widely used in interactive graphics applications, so it is significant to develop transparent rending method for fixed graphic pipeline. Alpha blending is widely applied in the fixed graphic pipeline to realize transparent rendering, but the result image is poor realism. Utilizing modern programmable GPU, the alpha blending factor was dynamically adjusted to achieve more realistic result image. The adjusting scheme is based on the following observation： regions around object silhouette look more opaque than the middle and in the case of lighting the direct light areas will be more transparent. This approach has been applied to self-developed “Digital LiPb loop simulation system”, which has lots of transparent pipelines, and the result is satisfying.

关 键 词：alpha混合 可编程GPU 轮廓不透明 光照 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]