Output details

Equivalence Principles Based Skin Deformation of Character Animation

Originality: Existing curve-based surface modelling approaches are purely geometric. The realism of curve-based skin deformation depends on the correct relationships between skin surfaces and the curves defining the skin surfaces. This research is the first to investigate the equivalent relationships of physical properties, geometric properties and externally applied forces between skin surfaces and their corresponding curves. It transforms the deformations of skin surfaces into those of the curves, and develops a fast, physics-based, and example skin shape-controlled technique to animate deformations of skin surfaces.

Significance: Realism is one of the main problems of skin deformation for character animation. By formulating the equivalent effects from the skin physics using wires, which are computationally cheap to calculate, this work enables quick creation of realistic skin deformation. It also laid a solid basis for our project “Integrated technique for fast and physics-based character modelling and animation” jointly funded by the Royal Society (£12,000, You) and the National Natural Science Foundation of China.

Rigour: The developed technique is based on the idea that the curves bounded a skin surface can represent the shape and control the deformations of the surface. The algorithms for determining the material properties, geometric properties and externally applied forces of the curves are developed from material equivalence, geometric equivalence and deformation equivalence. The determination of curve deformations is based on the physics of beam bending. The deformation transferring from the curves to the skin surface follows the geometric relationships between the curves and the skin surface. The correctness of these treatments is assessed and tested through the examples given in the paper.