Modeling Method for Hills in Visual System of Shiphandling Simulator
船舶操纵模拟器视景中的山形建模

Shiphandling simulator is a device that can partly imitate the true environment at sea,and is specially designed to satisfy marine education and trains and maritime research etc.One of its key techniques is to create the virtual environment at sea,and the terrain is its important component.According to the needs of the real time visual display of the shiphandling simulator, this paper analyses the requirements of the geometry precision of the important islands and background hills which are within the ships' visible scope,and brings forward the modeling methods of the hill's pileup and the hill's silhouette edges based on contour lines.It also presents the definition of error that the hill's silhouette edges graph has been given and the effective scope of application,and firstly established the error criterion of terrain model that is built in shiphandling simulator.With these two kinds of method,the size of data storage can be minimized greatly,and the requirements of high update rate and geometry precision for the real time visual display of the shiphandling simulator can be satisfied.