Shape-Aware2D Skeletal Deformation For Cartoon Characters

Computer animation is generated from the technical combination of computer graphics and arts. It enables the imagination and artistic talents of the individuals to be fully expressed where successive virtual images can be generated using knowledge such as math, physics, art and computer science. The technique is not only widely used in commercial ads, television programming, animation and entertainment, but also in computer education, flight simulation and even in the court.2D skeleton-based deformation for cartoon characters is an important computer animation technique. It allows the user to edit a given2D shape by using a single skeleton. However, traditional skeleton-based methods require vertex binding and weight setting which are both tedious and tend to produce distortion near the joints. Therefore, this paper presents a shape-aware2D skeletal deformation method. The main content of this paper includes:(1) A shape-aware2D skeletal deformation for cartoon is proposed. Difference from the traditional skeleton-based methods, it uses an optimization to propagate the skeletons’moving over the whole shape, which can effectively avoid vertices bind and weights set. In addition, considering the internal geometry of the cartoon in the process of optimization, the errors that occur near joints can be effectively eliminated. By exploiting the sub-space technique to perform the nonlinear optimization problem, the method enables the user to manipulate a shape using a skeleton in completely real time.(2) A hybrid sub-space outline simplified method via generating automatically is proposed. Aiming at the various vertices of original polygon which makes it difficult to generate sparse triangle mesh in its interior, a hybrid sub-space outline simplified method via generating automatically is proposed. In order to satisfy the properties of the polygon as the outline of the subspace, the algorithm deploys the simplified technologies:vertex deletion and edge contraction, gradually reducing vertices in the original polygon. The experimental results verify that the proposed method could reduce the vertices of original polygon effectively. The simplified polygon not only can be as approximate as possible to the shape of the original polygon, but also can surround the original polygons completely, ensuring to generate automatic the sub-space outline automatically.