点集模型的直接可见性测试与基于视点的绘制

点集模型作为一种新兴的三维几何形体表示形式,近年来备受关注.本文运用点集法向计算与凸包构建等技术,对原始点集模型进行直接可视性计算,并利用可见性计算的结果对点集模型进行基于视点的绘制.算法首先对原始模型进行基于视点的精简,剔除大部分不可见点；再对精简后的模型进行球面对称变换,并构建变换后点集的凸包,进而提取出可见点集；最后运用真实感图形绘制技术实现可见点集的快速绘制.实验证明,本文算法能够快速地计算点集模型中采样点的可见性.该算法可应用于点集模型基于视点的绘制与曲面重建,以及点集模型的阴影绘制等领域.

Direct Visibility Testing and Viewpoint-based Rendering for Point Sampled Models

As a novel representation technology of 3D geometric shapes,point-based model has attracted more and more interests of researchers in computer graphics society in recent years.In this paper,we present an algorithm for calculating direct visibility of point-based models by using techniques such as normal computation and convex hull construction,and the point-based models can be rendered in view-point dependent way.In our method,original point-sets are first simplified to remove some of invisible points and t...