传统的三维网格简化及多分辨率建模方法对数据量超出内存限制的大型网格模型已不适用.提出一种基于外存的网格简化和基于视点的细节层次控制方法.该方法建立在网格分割的基础上,利用分割边界的对应性,在一次遍历中对所有的网格分块进行简化,从而克服了通常的网格分割简化方法需要多次分割、重复简化的缺点;同时实现了针对大型网格模型的基于视点的选择件绘制.对模型进行绘制时,模型局部细节可以被快速抽取出来,并且网格的分辨率在整个模型表面呈连续分布.
Traditional mesh simplification and multiresolution methods cannot work on large models whose data sizes exceed the main memory. In this paper, we present a new out-of-core simplification and level-of-detail (LOD) control method based on an idea of mesh cutting. In our method, a large model is cut into small patches and these patches are simplified separately in one single pass, by utilizing edge correspondences. Furthermore, view-dependent refinement of the whole model is also supported by a muhiresolution structure-vsplit forest. When the model is rendered, the local details are rapidly extracted from the structure, and the LOD of the whole model is distributed continuously according to gaze-points of the viewers.