Smooth navigation of road map in 3D scene

With the rapid development of ITS, information about ITS become larger and more complicated than before. How to represent it integrally and effectively is the task we will face. This paper proposes a multi-level displaying approach that can display the whole map and its region of interest at the same time without multi-window switch and over-lap. Besides, in order to view the road map in reality, the road map is super-imposed on terrain map. Two methods adopted in the system provide two possible ways to get good user interface.