部分三角网格模型因数据量庞大而导致其不便于存储、分析和显示,本文提出了一种结合网格精细化方法的三角形折叠网格简化算法以解决此问题。首先通过3~(1/2)网格细分法确定待折叠三角形三个顶点的修正坐标,并根据修正坐标初步确定折叠点位置,然后引入折叠点的拉普拉斯坐标和原三角形法向信息来更新折叠点位置,最后由三角形折叠后该区域的体积误差和被折叠三角形的平展度共同确定折叠代价,从而使网格优先从较为平坦和特征点较少的区域开始依次进行三角形折叠简化。对多个模型进行了实验测试和数据分析,结果表明该方法能够有效精简网格数据,与3个不同类型的简化方法相比,该方法的简化效率最高,而且能有效保持原网格模型的几何特征并控制简化三角形的质量。
Considering that some triangular mesh models are inconvenient for storage,analysis and display due to enormous data volume,a simplification algorithm for triangular collapsed mesh combining with mesh refinement was put forward.In this method,the modified coordinates for three vertexes of the triangle to be collapsed were determined by usingthe 3~(1/2)surfacesubdivisionmethod,and the position of the folding point was preliminarily determined in accordance with the modified coordinates;then the Laplacian coordinate of the folding point and normal information of the original triangle were introduced to update the folding point position;finally,the collapse cost was caculated based on volume error of the area after triangle collapse and flatness of the collapsed triangle,thus enabled the mesh to preferentially carry out collapse simplification from relatively flat area with few feature points.Experimental test and data a-nalysis were established in multiple models,and result indicates that the method can effectively simplify the mesh data.Compared with three simplification methods of different types,the method can achieve the highest simplification efficiency,and can,at the same time,effectively maintain geometric characteristics of the mesh model and control quality of the simplified triangle.