Path to an Integrated Modelling between IFC and CityGML for Neighborhood Scale Modelling

Planning of the built environment requires two-levels of planning process, city/neighborhood-scale and building-scale levels. At the city/neighborhood-scale, Geographic Information System (GIS) is commonly used with CityGML as its open-source 3D format. Meanwhile, for building-scale, Building Information Modelling (BIM) is used, and Industry Foundation Classes (IFC) format is its open-source file format. Both technologies work on different data formats and data exchanges. The research is focusing on ways of exchanging information and bringing together CityGML and IFC. With local context input, the methodology could be considered as a framework to parametrically manage the information related to energy, environment, security, etc. In this project, two use cases were developed, such as visualization for a web application. Autodesk Revit and Graphisoft Archicad were used in developing the building models as a prototype for the transformation testing. The transformation system was developed using Feature Manipulation Engine (FME), by Safe Software. FME allowed us to restructure the data model (IFC) and transformed it to the destination data format (CityGML). The test results showed that from detailed BIM models, CityGML format, as well as a Sketchup file, could be generated. These models can be imported to web visualization applications for urban energy modelling