3D gis data model for indoor route finding

3D-based information is demanded increasingly as cities grow three dimensionally and buildings become large and complex. Use of 3D GIS is also getting attention as a means to handle such problems as 3D land uses, location-based guidance, path finding and emergency evacuation. However, most 3D modeling techniques are focused on the visualization of building surfaces or terrains and do not have topological structures that are required in spatial analyses. In order to perform analytic functions such as query and path finding at a indoor level, we need to incorporate topological relationship into 3D objects. In this paper, we present a method to build a 3D geodata model by integrating 2D GIS data structure and 3D model. We also show how to construct corridor network in 3D building model for route finding. Finally, we test different cases of route finding scenarios inside a building including normal O-D path finding and emergency evacuation.