Building Interior Model Interpolation between IFC and CityGML

The use of building interior model in indoor emergency response and building interior navigation is becoming more and more common. Although the LoD4 of CityGML can express building interior spatial information quite well, it is hard to gather or obtain the spatial data in the building. In particular, building interior model needs rich semantics information (e.g. the width of window) to perform extra calculation such as the fire evacuation scenario. This paper addresses this issue by presenting a framework of interpolation between IFC and CityGML, which uses IFCXML as intermediate output file. There are two advantages relative to the direct conversion. One advantage is that IFCXML is defined in XML which has better readability, scalability and flexibility than IFC, and IFCXML can be integrated into XML database or web service. Since IFC contains the whole construction engineering information, the other advantage is that we don’t need to convert whole the IFC file. The analysis results showed that this interpolation framework is practical and feasible, and it provides a partially converting solution between IFC and CityGML. Keyword: BIM, CityGML, IFC, IFCXML.