The goal of urban building mesh simplification is to generate a compact representation of a building from a given mesh. Local smoothness and sharp contours of urban buildings are important features for converting unstructured data into solid models, which should be preserved during the simplification. In this paper, we present a general method to filter and simplify 3D building mesh models, capable of preserving piecewise planar structures and sharp features. Given a building mesh model, a mesh filtering technique is firstly designed to yield piecewise planar regions and extract crease contours. The planar regions are used to constrain the simplification of the mesh. Mesh decimation is achieved through a series of edge collapse operations, which uses regional structural constraints and local geometric error metrics to handle planar and non-planar areas respectively. The proposed method preserves the mesh structure with meaningful levels of detail while reducing the number of faces. The effectiveness of this method is evaluated on various building models generated from different observation scales, and the performance is validated by extensive comparisons to state-of-the-art techniques.

简化城市建筑网格的目的是根据给定的网格生成建筑物的紧凑表示。城市建筑物的局部光滑度和轮廓清晰是将非结构化数据转换为实体模型的重要特征，在简化过程中应保留这些特征。在本文中，我们提出了一种通用的方法来过滤和简化3D建筑网格模型，能够保留分段的平面结构和尖锐的特征。给定建筑网格模型，首先设计网格过滤技术以产生分段的平面区域并提取折痕轮廓。平面区域用于约束网格的简化。网格抽取是通过一系列边缘折叠操作实现的，它使用区域结构约束和局部几何误差度量分别处理平面和非平面区域。所提出的方法保留了有意义的细节级别的网格结构，同时减少了面的数量。该方法的有效性在不同观察规模下生成的各种建筑模型上进行了评估，并且通过与最新技术的广泛比较来验证其性能。