强风作用下树木运动的可视化模拟

Visual Simulation of Tree Motion in Strong Wind

树枝摆动和树枝断裂是常见的自然现象之一,为了快速真实地模拟这种自然现象,提出了一套模型和方法.首先分析强风作用下树叶脱落和树枝断裂现象发生的机理条件以及树叶下落后和树枝发生断裂后的受力,建立了树叶下落以及断枝的运动模型;然后针对树叶脱落以及树枝断裂后下落过程中的碰撞问题,提出简单高效的碰撞检测算法;最后在此基础上设计了基于物理和统计的树叶脱落和树枝断裂现象的可视化模拟方法.在VC++6.0开发平台上结合OpenGL开发了树在风中运动的可视化模拟系统,通过调整模型中的参数可以得到不同风力作用下树木运动的可视化模拟效果.实验结果表明,文中方法是有效的,模拟效果真实.

Branches swaying and breaking with wind are common natural phenomenon. In order to simulate this natural phenomenon fast and realistically, a set of models and methods are presented. First, conditions for leaves falling and branches breaking with strong wind are analyzed, forces applied to the fallen leaves and broken branches are also discussed, and then a moving model is built for leaves falling and branches breaking. Then, effective collision detection algorithms are proposed to solve the collision problems during the falling of leaves and broken branches. Finally, based on these models a visual simulation method which based on physical and statistics for the leaves falling and branches breaking is designed. A visual system for simulating the tree swaying in wind is developed using VC＋＋6.0 and OpenGL. Visual simulation results in different strong wind can be obtained by varying the simulation parameters in the system. The experiments show that our method is effective and can achieve vivid simulation.