Abstract
Conventional two dimensional (2D) maps and DEM's are insufficient to represent geographic information in urban space comprising high-rise buildings and underground structures. There is a pressing need for a model of three dimensional (3D) representation of urban space, that is, a Digital Urban Space Model (DUSM) . However existing solid modelling techniques cannot be directly applied to the 3D representation due to several problems such as the inefficiency in building and updating 3D spatial database. Based on the boundary representation (BR) model, the authors propose a Surface Representation (SR) model which can greatly improve the efficiency in building and updating 3D spatial database. Through an example of the 3D representation of urban space, it is demonstrated that the SR model can be successfully applied.
