提出一种基于2次误差测度（QEM）的网格简化改进算法。算法首先对折叠边所产生的新顶点定义其在初始网格上的简化支撑域，从而建立新顶点与初始网格之间的联系；然后计算新顶点到支撑域的2次距离误差作为该顶点的全局简化误差，并将原始QEM中的误差作为局部简化误差；最后将两个误差之和作为新的折叠代价目标函数以实现对原有QEM算法的改进。多个模型的简化实验表明，改进算法能较好地保留初始网格的细节特征，并且较为明显地降低简化误差。

An improvement to quadric-error-metrics-based mesh simplification algorithm is presented in this paper. Firstly， the support region on the original mesh is defined for the new vertex generated in an edge collapse operation, and the connection between the new vertex and the original mesh is established. Secondly，the quadric distance error from the new vertex to its support region is calculated as the global simplification error, and the original quadric error is regarded as the local simplification error; Finally the sum of the two errors is defined as the new cost function of the edge collapse operation. Experimental results demonstrate that the improved algorithm can preserve the details better than the original one and reduce the simplification error obviously.