中文摘要：

分析了位于建筑物多边形外侧的凹部结构特征及其类型,探讨了一种基于凹部层次结构的建筑物多边形渐进式化简方法,即以三角形为形状基元,用约束Delaunay三角化方法对建筑物多边形进行空间剖分,从凹部三角形树中提取三角形序列,通过匹配特征序列识别凹部的基本模式,以确定和实施相应的凹部化简方法,在此基础上迭代执行识别-化简过程,以实现对建筑物复杂凹部的渐进式化简。实验分析表明,该方法具有结构化和渐进综合的特点。

英文摘要：

We analyze the characteristics and the types of the concave structures outside the building polygons,and discuss a progressive simplification method based on the hierarchical structure of the concave.In the method,a building polygon is partitioned by constrained Delaunay TIN,and as shape primitives,triangles are used to build the concave triangle tree and to extract triangle sequence.The basic patterns of concaves are recognized by the matching of the typical sequences,which confirm and adopt the corresponding concave simplification methods.On the basis of this,the progressive simplification of complicated concaves of buildings is realized through repeating the process of recognition and simplification.The experimental results show that our method have the features of structure and progressive generalization.