Bilayered approximate integration for rapid and plausible animation of virtual cloth with realistic wrinkles

We present an efficient method for rapid animation of mass-spring model with a large number of mass-points. Realistic cloth simulation requires large amount of time in general. This is not only because the calculation for one step requires much time but also because the cloth simulation easily tends to become unstable. Although the implicit method can make the simulation stable, it is still impossible to generate interactive animation when the number of mass-points is sufficiently large enough to represent realistic wrinkles. An efficient animation method proposed by M. Desbrun (1999) also involves O(n²)-sized matrix so that it cannot be applied to models with a large number of mass-points. A stable approximate method without matrix operations has been introduced by M. Oshita and A. Makinouchi (2001), but its physical correctness is significantly impaired as the stiffness increases or the timestep becomes large. In this paper we propose a bilayered approach for efficient cloth animation with a large number of mass-points. The proposed method uses two mass-spring meshes. One of them is a rough mesh for representing global motion, and the other is a fine mesh for realistic wrinkles. The experimental results show that the method can be successfully used for real-time animation of plausible cloth models.