用分形理论模拟山峰和云

Visual Simulation of Mountainous Terrain and Clouds Using Fractal Theory for a Flight Simulator

讨论了飞行模拟器上自然景象的生成与显示，并着重研究了用分形几何理论来产生山峰地貌和云彩等景象。

The project of 'the realistic image generation and display of the natural scene for a flightsimulator' was supported by China Science Foundation of Aeronautics. Our simulation ofclouds and mountainous terrain was done on PC VGA Screen based on Fractal theory.The cloud contour was constructed by super-and / or para ellipse surface in only oneway-instead of by two ways-plane and ellipsoid as had been done previously. Then usingnormal perturbation and texture function successively, we can reduce the number of iterations of cloud calculation by about 50%. An approach to the synthesis of tractal mountainous terrain models, termed noise sgthesis, is introduced. In contrast to the previous techniques, this approach features the localcontrol of fractal dimension and other statistical characteristics as well as altitude of mountains.