一种基于半拉格朗日的液体实时仿真方法

近些年,在计算机图形学与虚拟现实技术领域中,自然现象的模拟得到了广泛的关注和研究.如何快速且逼真地模拟自然现象,是此类研究的目的.以液体表面作为研究对象,总结了关于液体模拟近年来的部分研究成果;针对三维液体的复杂流体状态,提出了一种基于半拉格朗日的液体实时仿真方法,并对仿真结果进行了表面构建.该方法首先将Navier-Stokes 方程离散化,并通过求解构造的Poisson 方程得到每一时间步长的数值解,进而精确驱动粒子运动以构建真实液体表面;之后,利用液体表面追踪及Marching Cubes 表面重建,生成了真实的液体表面模型.实验结果表明,该仿真方法不但在运算过程中遵循经典的流体力学方程,从而保证了结果的真实性,并且运算速度快且能取得较好的视觉效果.在计算机游戏、电影制作以及医学等领域的仿真,均有广泛的应用前景.

Real-Time Approach for Dynamic Liquid Simulation Using Semi-Lagrangian

In recent years, natural phenomena simulation attracts a spurt of research attention and interest in computer graphics and virtual reality domain. How to obtain realistic natural phenomena by simulation in an efficient way is the main purpose of this research field. This paper summarizes the main research achievements on the topic of liquid simulation. A real-time liquid simulation method based on semi-Lagrangian is proposed for liquid simulation, followed by a surface reconstruction method using simulated results. In this approach, Navier-Stokes equations are first discretized in both spatial and temporal dimensions. Second, by solving the constructed Poisson equation, numerical solution for each time step is obtained. Third, particle movements are accurately driven by the solved velocity field in order to simulate the dynamics of water. By applying surface tracking and Marching Cubes algorithm, water surface is finally extracted. Experimental results show that the simulation speed of this method is high enough for real time use. Satisfactory visual effect is also obtained, facilitating the usage of this application in computer games, movie making and virtual simulation in medical area.