Shape modeling for animated characters using ordinary differential equations

In this paper, we develop a new approach to animate skin deformation of character models. It aims to combine the strengths of joint-based approaches, physics-based algorithms and curve-based surface modeling methods together for efficient and realistic animation of skin deformation. We first transform the deformation of skin surfaces of character models into that of the curves defining the skin surfaces, and introduce a mathematical model consisting of a vector-valued fourth order ordinary differential equation and boundary conditions to describe the curve deformation. In order to achieve capacity and high animation efficiency, we propose an efficient finite difference solution of the mathematical model, and apply our proposed solution to animate skin deformation of character models. The application examples demonstrate that our proposed approach can create realistic skin deformations for real-time character animation.

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