Research And Realization In Dynamic Cloth Simulation

With the development of virtual reality and computer animation, as well as the demands in the fields of garment CAD,et al, the dynamic cloth simulation becomes a more and more important research domain. Cloth modeling is the base of cloth simulation. Based on the analysis of cloth physics performance and previous cloth models, mass-spring model is adopted and then the kinetics analysis is made on the model, the differential equation for each mass is deduced. To solve the differential equation, fourth-order Runge-Kutta method is a good candidate for obtaining the dynamic cloth shape in 3D space. However, the mass-spring model has the "super elastic" effect in simulation. In this paper, compared to the previous methods of dealing with this problem, a feasible method is proposed by constructing a non-linear function to adjust "super elastic" effect of cloth model, so the problem is settled effectively. The dynamic display has great influences on cloth simulation. In this paper, a function and algorithm for wind is also proposed, improving the computing efficiency and display effect.Collision detection and collision response are key problems in dynamic cloth simulation. This paper introduced the collision detection algorithm on the basis of bounding boxes hierarchy. With this approach, the collision and self-collision detection achieve real-time performance. Based on collision detection algorithm, the paper proposed a method transforming the self-collision problem into collision problem by recursion. The collision detection algorithm between basic geometrical units (triangle), which come down to point-triangle collision, is also an important step in collision detection. If collision occurred, the next step is collision response process according to mechanics principle. Texture mapping is also an important part in cloth simulation. This paper researches the methods of texture mapping from 2D to 3D, and maps a texture picture to cloth model, so the cloth has real appearance. Our subject is developed with VC++6.0 and OpenGL, and object-oriented programming thought is adopted. It has realized the dynamic cloth simulation according to the sequence of modeling, numerical integrating, collision detection, collision response and texture mapping. The results show that the methods above arrive at the vivid and real-time effect, and lay the foundation for further development.