The Research On Plant Animation Technique Based On Physical Model

Trees and plant are the important part of the nature scene. There are various species of trees on the plain, mountains and all over the world. They can be different scenes with the season's changing. So its significance needn't to be emphasize in simulating the complex nature scenes and the phenomena of nature. At present, there is not many works on the animating the trees, the main work are focus on the modeling and rendering. This paper present a method on animating the trees based on the physical model. It can model various trees with fast and realistic animation under the winds or other forces.This paper researched the physical-based animation techniques of trees. First, combining the material mechanics and computer data structure, present a physical model by integrating the various material characteristics of trees. It can express the branch and leaves of trees nicely, can express the shape, material and movement characteristics of trees. For example, the Yang's modulus, shear modulus, and the cohesive coefficient in the air. It can provide the necessary parameter for the movement model. It is also easy to be obtained from the existing modeling system, e.g. Arbaro. Then, found the movement model of branch and leaf respectively based on the movement characteristics when they are under wind force or other forces. Decompose the branch's complex movement to bending and rotation. And decompose the leaf's movement to three parts: leafstalk's rotation, leaf surface's rotation and bend. Obtain the movement's direction, velocity, and range of the branches and leaves by simple rigid body movement rule and the physical model presented in this paper. This method is general used technique; it can be use on the most of trees and plants. It replaced the finite element method by algebra equation, so it reduce the computing time of build the animation, increase the efficiency. The mostimportant is that it can make very wonderfully visual effect.