文章基本信息

标题：Generalization of buildings within the framework of CityGML
本地全文：下载
作者：Siddique Ullah Baig ; Alias Abdul-Rahman
期刊名称：Geo-spatial Information Science
印刷版ISSN：1009-5020
电子版ISSN：1993-5153
出版年度：2013
卷号：16
期号：4
页码：247-255
DOI：10.1080/10095020.2013.866617
出版社：Taylor and Francis Ltd
摘要：For a better visual impression, 3D information systems and architecture need detailed, photo-realistic visualization of 3D data-sets. However, easy accessibility with efficient rendering becomes difficult due to the detailed data associated with 3D objects. Therefore, different applications demand different levels of detail (LoD). Currently, City Geography Markup Language (CityGML), as the Open Geospatial Consortium standard, is being used to model and represent buildings in different LoDs (LoD0–LoD4), but it does not provide methods to generate different LoDs automatically. Thus, generalized (abstracted) 3D scenes of buildings need to be generated to fulfill the demands of task-specific applications by reducing data volume. This paper discusses various ways to generalize building models, within the framework of CityGML, reducing the level of detail from higher LoD to lower. The LoD4 data is parsed and analyzed. Various heuristics are applied to simplify the ground plan and the results are then aggregated. The minimum length of an edge for simplification is restricted to the CityGML generalization specifications provided and is characterized by differing accuracies and minimal dimensions of objects for LoD1 and LoD2. This could maintain the accuracy of generalized objects and avoid the elimination or merging of important features. Second, the heights of the walls of the simplified ground plans are raised with the aim to construct simplified 3D building models. Algorithms for simplification and aggregation aiming to derive LoD2 and LoD1 are implemented and tested on a number of buildings of Putrajaya, Malaysia. The experiment results show that the minimum length of edges to be simplified is inversely proportional to the size of generalized models.
关键词：CityGML; 3D; simplification; aggregation; city models