针对计算机图形学中大规模水域雨场景绘制的难题,提出了-种适合大规模水域雨场景实时绘制的方法。将改进的波动方程引入雨天湖面波动以及雨滴与湖面的交互效果模拟中,结合快速傅里叶变换的风力趋向性以及周期性,建立了雨天水面交互波动的数学模型,根据数学模型构建了雨天水面交互高度图,通过光照渲染,实现了湖面反射效果和雨线绘制。为了提高模拟效率,整个过程在GPU中实现,并采用基于四叉树的多细节层次技术进行加速。在1 440*900的 图像分辨率下,帧速达到了98 fps,满足了实时交互模拟的需求。
The rendering of large-scale water area rain scene is one of the most challenging problems in computer graphics, and a method of rendering large-scale water area rain scene was proposed. By introducing the improved wave equation into the fuctuation of water surface and the interaction of water and raindrop, and incorporating the periodicity and wind tendency of FFT, an interactive fluctuation of water mathematical model in rainy days was established, based on which an interactive height map was rendered. Through the lighting rendering, the reflection effect and rain streaks were simulated. In order to enhance the efficiency, the level-of- detail techniques based on quad-tree were applied and the newest GPU acceleration was applied in order to take its full advantages. The method is efficient and achieves qualified refreshing frequency in real time scene rendering.
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