摘要： 在计算机图形学中，经常采用网格模型对物体和场景进行描述，而网格模型的大数据量成为实时绘制的瓶颈。因此，必须对网格模型进行简化，目前的简化算法，主要是以网格模型几何误差的最小化为准则，而忽略了模型的视觉特征。文章提出了一种基于视点的网格模型简化算法，其简化准则是视觉特征的最优化，利用视点相关，建立视点与网格精度的对应关系，对距离视点较近的部分采用较密网格，对距视点较远的部分采用稀疏网格。实验结果表明，该算法能够在保证高度真实感视觉效果的前提下，实现模型较大幅度的简化。

关键词: 地形模型；模型简化；判决准则；多边形网格

Abstract: In computer graphics, object and scenes are often described by mesh models. However, a large complicated model often includes large-scale data, which is a bottleneck of real-time rendering, so it is necessary to simplify mesh model. The simplification criteria of many algorithms is minimizing the geometry errors now, the visual effect of the model is ignored. This paper gives a mesh model simplification algorithm based on the viewpoint and the rule of this algorithm is the optimization of visual effect. According to the correlation of the viewpoint, the relation between the viewpoint and the precision of the mesh is built, thick mesh is applied to the part far away form the viewpoint; thin mesh is applied to the part near the viewpoint. A group of experimental result is also given, which illustrates that the above algorithm can realize model simplification effectively, and at the same time, keep the models high reality and good visual effect.

Key words: Terrain model; Model simplification; Judging criteria; Polygonal mesh