chart datum
2.The data model and file structure of ENC(electronic navigational chart) in accordance with IHO-57 transmission standard are introduced in this paper. Applying the scattered sounding points and coastline datum in ENC,and the correlative technology of OpenGL,the dynamic wave surface can be created with the dynamic light of seamark or light house,as well as the surface model of seabed which meets the Delaunay regulation.
