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With the increasing maturity of computer science and technology and the rapiddevelopment of its hardware and software, computer graphics and virtual realitytechnology have been used more widely in television animation, computer games,industrial simulation, military simulation, etc. Realistic simulation of natural scenes hasalways become one of the most challenging researching hotspots in computer graphicsand virtual reality. Because of natural scenes have the characteristics of varied andcomplex form, irregular movement and the random variation, it is difficult to describeand research according to the general geometric model. The ocean is important part ofthe natural scenes. Compare to the simulation of plant terrain, mountain waterfalls,flame rain and cloud, ocean modeling involves its boundlessness, the fluctuating law ofthe ocean surface not only extremely complex, but also influenced and effected byoptical properties and various kinds of force, and also having higher requirement on thereality and real-time, these features make the ocean simulation more challenging.In this paper, we discuss form the current researching of virtual reality technologyand ocean simulation technology, combining with current large-scale ocean modelingand simulation technology, given the basic steps of ocean simulation and madeimprovements. As a result, we achieve the satisfactory results weighing the reality andreal-time, which can be applied to the actual needs and the efficient subsequentdevelopment.In research of modeling the ocean surface grid, we used projected grid algorithm, itis according with human visual regularity and having the natural attributes LOD nature.The projected grid is different from the trapezoidal or rules rectangular grid, it is presentin the projection space does not exist in the world space. We analyzed and solvedproblems appear in the algorithm process, improved it and proposed a non-uniformsampled projected grid algorithm.In research of modeling the ocean waves, after introduction and analysis ofcommon waves modeling method, we ultimately chose the high efficiency perlin fractalnoise as the ocean wave’s height field disturbance source, as well as improved harmonic interpolation method in structuring two-dimensional noise, to obtain better results.In research of simulating the ship waves, we specifically analyze the simulationmethod based on solving two-dimensional wave equation of finite difference method(FDM), and realized based on the theory particle system simulation method. The later isaccording the ship wave external force to build described by the equations of motion,the simulation results show that the particle system-based approach, both to the rightsimulation of ship when traveling trails, but also reduces the computational complexity,showing a strong sense of reality.In research of ocean interacting with light, we used the texture mapping techniquesto implement the sea effects such as reflection, foam, caustic, etc.In the end, this paper analyzes problems and deficiencies in the system oflarge-scale3D ocean simulation, and summarizes improving direction and furtheroutlook.
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