不同形态水与树木交互作用可视化仿真研究

Visualization on simulation of interactive coupling between water and a tree is one of hot problems in the field of computer graphics. The research has a very important practical significance. This project focuses on the research of interactive coupling between a tree and four different common forms of water (rain, glaze, rime, hail) in which has been involved by few researchers. (1)Raindrops-and-tree interactive coupling: The crown space is divided into two layers, inner and outer. A statistics-based approach is proposed to simulate the raindrop’s distribution and transmission in inner layer; a physically-based method is used to simulate raindrop’s motions along the crown surface such as collision, splashing, flow and branch’s motions such as rotation and swaying. (2) Glaze/Rime-and-tree interactive coupling: A simplified physical model is proposed to simulate branch’s crack due to the glaze/rime-accumulation pressure in different surrounding conditions. (3) Hail-and-leaf interactive coupling: A method is proposed to simulate the hail’s penetration into or dilacerations to a tree leaf, considering the factors of relative masses and velocity between hails and leave. (4) A speed-up rendering approach is proposed to realize a more realistic effect of different water scene, such as the light’s reflection and refraction in it..This research project has a very important practical significance in the fields of computer graphics and agriculture and forestry.

水与树木交互动态模拟可视化是计算机图形学领域的热点研究问题之一。本项目重点研究鲜有人涉及的树木与四种常见的不同形态水（雨、雨凇、雾凇、冰雹）的交互作用的算法：（1）雨滴与树木交互模拟：按空间将树冠分为表层和内层两个部分，提出基于统计学的雨滴在树冠内层模型中分布、传输算法，提出基于物理的雨滴与树冠表层枝叶间碰撞、飞溅、流动以及树枝振动和转动等算法。（2）雾凇/雨凇与树木交互模拟：在不同外部条件下，提出基于简化物理模型的雾凇/雨凇在树木上累积算法以及过压力下树枝断裂算法。（3）冰雹与树叶交互模拟：综合考虑冰雹与树叶间相对质量和速度大小等因素影响，提出冰雹撞击后树叶被穿透/撕裂算法。（4）提出不同形态水场景对光线的反射、透射等现象的具有真实感效果的快速绘制加速算法。.本项目的研究在计算机图形学与农林业领域具有重要的价值。

水与树木交互动态模拟可视化是计算机图形学领域的难点与热点研究问题之一。本项目重点研究了树木与四种常见的不同形态水（雨、雨凇、雾凇、冰雹）的交互作用的算法：（1）提出基于物理的雨滴与树冠表层枝叶间碰撞、飞溅、流动以及树枝振动和转动等算法。（2）提出基于简化物理模型的雾凇/雨凇在树木上累积算法以及过压力下树枝断裂算法。（3）提出冰雹撞击后树叶被穿透/撕裂算法。本项目完成了一套交互动态效果可视化的演示软件系统；在该项目的资助下，共发表论文19篇、获得软件著作权11项、申请专利5项、申请到项目资助4项。本项目的关键数据有现实世界中树木的三维几何数据、雨凇/雾凇与冰雹的外形数据等。本项目的研究结果在计算机图形学与农林业领域具有重要的应用价值与决策参考意义。