Abstract: Real-time rendering of large scale terrain plays an important role in virtual reality,
battlefield simulation and training areas and so on. To meet the requirements of scene simulation in
ship navigation training, the modeling and rendering of large scale terrain are studied. Some usual
DEM interpolation is studied at first, and then the DEM interpolation based on data fusion is used.
According to the practice of navigation training, a terrain culling method based on visibility
estimation is proposed. The method uses radiated ray and searches for if there are points whose
height is larger than the occlude ones. If there is a point with a larger height in all direction, it means
that this point is being occluded. We cull all the occluded points to reduce the terrain model. At last,
a terrain modeling method based on Google earth and Terri Vista is introduced. The results show that
this method can get a good performance in real-time with no hurt to the verisimilitude.

Key words: terrain, modeling, visibility culling, scene simulation