基于GPU的大尺度河流表面实时绘制

Real–Time Rendering of Large-Scale River Surface Based on GPU

为提升内河船舶操纵模拟器视景系统的环境真实感,提出基于真实河道岸界构建河流速度场解算模型。基本思想是构建恰当的流函数,之后利用流函数的性质求解河流的速度场。将解算的速度场传输到向量图瓦片中,最终基于GPU和GLSL着色器实现大尺度河流表面的渲染。选择内河船舶操纵模拟器中海图50000进行测试,解算的河流速度场与河道方向一致,河流表面绘制帧率达60帧。结果表明求解的河流速度场可真实地体现河流流动性,能显著地提升河流视景系统的环境真实感,且满足仿真实时性。

ABSTRACT ： In order to improve the environment realism of visual system of maneuvering simulator for river vessels, the paper presents a calculating model for flow velocity field based on real river bank. The basic theory is to build up an appropriate stream function, and then caculate the flow velocity based on the property of stream function. The ve- locity field was transmitted to normal map tiles, and rendering large-sacale river surface based on GPU and GLSL shader. Chart No. 50000 in inland river ship maneuvering simulator was taken as an example of the test algorithm. The caculated flow velocity field conforms with the direction of river channel, and the frame rate of rendering river su- face is up to 60 fps. The results show that the caculated velocity can reflect river flowing, and greatly improve envi- ronment realism of visual system in inland ship handling simulator as well as meet the real time requirement.