一种保持特征的网格简化算法

针对网格简化算法中出现的细节特征丢失、简化结果过于均匀以及计算复杂等问题,从原始模型的几何特征出发,对待折叠三角形与其邻域内三角形的形状与位置关系进行研究,对三角形折叠点到其三个顶点的偏离程度进行总结,提出了一种基于三角形折叠的保持模型特征的网格简化算法。该方法根据目标三角形各顶点邻域三角形的不同,为其3个顶点分配相应的权值,由各顶点权值的大小最终确定三角形折叠点坐标,然后以二次误差测度为度量标准计算出每个三角形的折叠代价,再结合三角形局部面积比、局部区域不平度以更好地控制简化结果。实验结果表明:该方法能够降低计算的复杂度、提高简化速度,使模型的特征区域和非特征区域均保持一定的简化率,并较好地保持了原始模型的细节特征。

Method of mesh simplification based on feature preserving

Aiming at the problems that the detail features of the mesh models were lost, the effects of mesh simplification were ex-cessively even-distributed and the algorithm were time-consumed, starting with the geometric feature of original model, the geomet-rical and positional relationship between target triangle and its adjacent triangles was analyzed, the level of folding point departure from its vertexes was summarized, a feature preserved method of mesh simplification was proposed based on triangle collapse. Ac-cording to the difference of every vextex's adjacent triangles of target triangle, various values were distributed to each vertex to calculate the coordinates of contracting point, combined with local area ratio of triangles and local region irregularity, the final er-rors were figured out to get better effects. The results indicate that this method can lower the computation complexity, improve the speed of mesh simplification, at the same time, keep appropriate simplification rate in both characteristic region and flat site, and maintain the detail features of original model well.