Cengiz Öztireli1, Ilya Baran2,3,4, Tiberiu Popa1, Boris Dalstein5, Robert W Sumner2, Markus Gross1,2
1ETH Zurich 2Disney Research Zurich 3Belmont Technology, Inc. 4Adobe Research 5University of British Columbia
Generating highly expressive and caricatured poses can be diffi- cult in 3D computer animation because artists must interact with characters indirectly through complex character rigs. Furthermore, since caricatured poses often involve large bends and twists, arti- facts arise with traditional skinning algorithms that are not designed to blend large, disparate rotations and cannot represent extremely large rotations. To overcome these problems, we introduce a dif- ferential blending algorithm that can successfully encode and blend large transformations, overcoming the inherent limitation of previ- ous skeletal representations. Based on this blending method, we illustrate a sketch-based interface that supports curved bones and implements the line-of-action concept from hand-drawn animation to create expressive poses in 3D animation. By interpolating stored differential transformations across temporal keyframes, our system also generates caricatured animation. We present a detailed techni- cal analysis of our differential blending algorithm and show several posing and animation results created using our system to demon- strate the utility of our method in practice.
Links:
PDF Project page