地形TIN模型的实时连续LOD算法设计与实现

为了实现基于不规则三角网(TIN)地形模型的动态细节简化模型,文中介绍了一种有效的方法,即在一种新的三角网数据结构基础上,通过重复执行模型中边的“折叠”(即顶点“合并”)操作,预先计算模型中每个顶点“重要性”值,根据“重要性”对模型的三角形和顶点列表进行重新排序并将结果存储在数据结构中。在显示过程中,根据对地形的精度要求和事先存储的结果自适应地快速获取所要显示的顶点和三角形,实现TIN模型的买时动态构网显示。基于该算法,在两个不同细节的TIN模型进行过渡时可以进行快速线性插值,实现了不同细节模型间的连续过渡。

An Algorithm of Dynamic Triangulation for the TIN Model of Terrain

This paper discusses an algorithm of dynamic triangulation for TIN model of terrain. Based on a new data structure designed for TIN, with the repeating edge collapse transformations in "progressive meshing", the important value of every points in model has been calculated and saved in such data structure before rendering. Then the order of points and triangulations in model has been changed and saved by important value too. When rendering, the model's TIN is dynamically triangulated directly by the saved informations in data structure. With this algorithm, the continuous triangulation between different levels of detail models will also come true.