复杂几何模型动态视相关的简化  

Real-Time View-Dependent Simplification ofComplicated 3D Model

作　　者：淮永建[1] 郝重阳[1] 罗冠[1] 张先勇[1] 

机构地区：[1]西北工业大学电子工程系,陕西西安710072

出　　处：《西北工业大学学报》2002年第2期337-341,共5页Journal of Northwestern Polytechnical University

摘　　要：基于三角形网格边折叠的思想,提出了一种新的多边形简化算法以快速生成多层次细节的LOD模型。在析叠边的代价估计中,均衡考虑了多边形边的长度和多边形表面曲率影响;折叠边的顶点位置从折叠边的顶点中选取,既有助于保留了初始模型的形状,又减少运算量,满足实时绘制的需求。在依据视点选择适当LOD模型时,采用了顶点 morphing技术光滑多边形模型,减少不同层次LOD模型转化时引起的图像‘跳跃’。在算法实现中,采用增强的多边形数据结构,并用一算例证明了算法的有效性。Starting from Hoppe's paper on view-dependent refinement of progressive meshes[7], we not only improved on it but more importantly also proposed a new algorithm of polygonal simplification that can make real-time graphics rendering possible. We proposed eq. (1) to define an important concept: cost of edge collapse. We also proposed vertex morphing in subsection 1. 4 to reduce image popping which is a serious problem during LOD level of detail transition if real-time graphics rendering is necessary. In subsection 2. 1, we discussed how to improve the polygonal data structure to facilitate the iterative calculations of the cost of edge collapse. The positioning of new vertex is important in our new algorithm and in subsection 1. 1 we discussed how to position it. We implemented our new algorithm and in it we believe that we achieve a good trade-off between image quality and rendering speed.

关 键 词：复杂几何模型 动态视相关 实时图形绘制 多边形模型简化 多层次细节模型 边折叠 顶点渐变 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]