Interoperability between building information models (BIM) and geographic information models has a strong potential to bring benefit to different demands in construction analysis, urban planning, homeland security and other applications. Therefore, different research and commercial efforts have been initiated to integrate the most prominent semantic models in BIM and geospatial applications. Th...

One of the main problems facing 3D city modelling applications is lack of interoperability among various Building Information Models (BIM) and Geographic Information Systems (GIS) models. CityGML (representing a wide range of 3D urban objects) and IFC (representing a very detailed semantic model for buildings) are considered the most prominent semantic models in GIS and BIM, respectively, today...

This paper describes the usage of MUSCLE (Multidirectional Scanning for Line Extraction) Model for automatic generation of 3D networks in CityGML format (from raster floor plans). The algorithm of the model implements line thinning and simple neighborhood methods for vectorization. The model allows user to define specific criteria which are crucial for acquiring the vectorization process. The n...

This article describes a research project that realised a national standard for 3D geo-information. The standard was developed as part of a pilot in which more than 65 private, public and scientific organisations collaborated to analyse and push 3D developments in the Netherlands (run between March 2010 and June 2011). The 3D standard was established through several steps. Firstly a comparison ...

Virtual 3D city models are becoming increasingly complex with respect to their spatial and thematic structures. CityGML is an OGC standard to represent and exchange city models in an interoperable way. As CityGML datasets may become very large and may contain deeply structured objects, the efficient storage and input/output of CityGML data requires both carefully optimized database schemas and ...

We investigate the automatic conversion between two substantially different formats used in 3D city models: the ubiquitous but semantically poor Wavefront OBJ and the semantically rich but less used OGC standard CityGML. We elaborate on their differences and on the challenges involved in their conversion, such as the inference of semantics in an OBJ file for their use in CityGML, and the storag...

Recently a national 3D standard was established in the Netherlands as a CityGML Application Domain Extension (called IMGeo). In line with the Dutch practice of modeling geo-information, the ADE is developed using a model driven approach. The classes are designed in UML and automatically mapped to GML schema. The current OGC CityGML specification does not provide rules or guidance on correctly m...

We propose a new Level of Detail (LoD) concept for CityGML buildings that differentiates a Geometrical Level of Detail (GLoD) and a Semantical Level of Detail (SLoD). These two LoD concepts are separately defined for the interior characteristics and the outer shell of a building, respectively. The City Geography Markup Language (CityGML) is an open and application independent information model ...

This paper presents key aspects of the development of a Dutch 3D standard IMGeo as a CityGML ADE. The new ADE is modeled using UML class diagrams. However the OGC CityGML specification does not provide clear rules on modeling an ADE in UML. This paper describes how the extension was built, which provides general insight how CityGML can be extended for a specific applications starting from the U...

CityGML provides an effective approach to the sharing and inoperability of 3D GIS spatial data. However, due to the large amount of data, CityGML’s resolving, transferring, and rendering processes during visualization are inefficient in a standalone system, causing considerable delays in viewing the information of large 3D maps for users. The cloud computing technique is introduced to address t...