Research On Algorithm For Simulating Ocean Waves Based On Spectrum Of Ocean Waves

Simulation of natural scenes is one of the greatest challenges in computer graphics, and it is applied widely in CG cartoon, texture making, games,films, virtual reality and engineering domain. Ocean waves are an important part of natural scenes. It is difficult to simulate ocean waves because of its wide space and random movement. In this thesis we mainly discuss modeling ocean waves based on spectrum of ocean waves and real-time rendering technology, and we also propose some improvement for these algorithms and models.Modeling ocean waves based on spectrum technology, which uses the observation and research results of oceanography, represents real ocean waves datum. But this technology usually expresses ocean surface with height field, in another word, every point of ocean surface only has one height. So this technology can not be used to express waves whose crests are curly. This problem can be resolved by Gerstner model, but the model lacks in realism. So the above two methods are combined and a 3D Gerstner waves model based on spectrum is obtaind in this thesis. First, we define dispersed form of 3D Gerstner model in our model, then obtain all parameters of the 3D Gerstner model under certain wind speed utilizing frequency spectrum and directional spectrum of ocean waves. At last, an ocean waves scene under certain wind speed is achieved. Wind force should be taken into account when simulating ocean waves, as wind force drives waves to move. Because spectrum of ocean waves is short of observation information about the affect of wind force on ocean waves, a wind force model is constructed to simulate ocean waves under wind force. A view-dependent grid technology is investigated to enhance rendering speed because of wide space of ocean waves. This method can create irregular grid of different levels depend on viewpoint real-time, avoiding to clip infinite sea area, and save memory.At last, an ocean waves demo system is realized according to above methods. Experiment results show that the above methods give attention to realism and real-time simulation, and it can not only simulate ocean waves whose crests are curly, but also embody that wave crest is steeper and wave trough is flatness which is the character of ocean waves.