Realistic Rendering of Ship Waves for Marine Simulator

摘要

When a ship sailing on the sea, the change of pressure generated between ship hull and water will cause water waves on ocean surface. These waves are called ship waves, which is a very significant problem for ship design and waterway engineering researchers. The study on ship waves also is an important issue for Marine Simulator. Precise calculation of ship waves could provide accurate data source for ship motion mathematical model. Realistic rendering of ship waves will improve the immersion and realism sense of operators greatly and could provide more feedback of navigation environment information and state to operators. To render ship waves realistically will improve the visualization effect greatly for Marine Simulator. A simple and efficient ship waves rendering method for marine simulator is presented and implemented in this paper. The waveform heightmap is established based on the Kelvin wave method. The whole ship wave is separated as several disturbance sources. The center of disturbance sources moves along the ship. Each disturbance source is represented as a couple of particles. Each particle has its own physical attributes, such as position, height and so on. The height attribute of each particle represent the height of disturbance source at the specified position. For simplicity and efficient simulation, the Kelvin wave peak track function is modified and the track scale is restricted for calculating ship bow waves only. All the particles of each disturbance source are interpolated and smoothed for generating wave heightmap. Then the final heightmap is added to the sea surface heightmap for ocean rendering. All the calculation and rendering process uses GPU for accelerating. The test results show that the proposed method could splice the ship bow wave seamlessly with current sea heightmap and gets a realistically rendering result in real-time by a PC.