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A Multi-resolution Approach for Adapting Close Character Interaction

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Synthesizing close interactions such as dancing and fighting be-tween characters is a challenging problem in computer animation. While encouraging results are presented in [Ho et al. 2010], the high computation cost makes the method unsuitable for interactive motion editing and synthesis. In this paper, we propose an efficient multiresolution approach in the temporal domain for editing and adapting close character interactions based on the Interaction Mesh framework. In particular, we divide the original large spacetime optimization problem into multiple smaller problems such that the user can observe the adapted motion while playing-back the move-ments during run-time. Our approach is highly parallelizable, and achieves high performance by making use of multi-core architec-tures. The method can be applied to a wide range of applications including motion editing systems for animators and motion retar-geting systems for humanoid robots.
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... These methods aim at transferring the topology of the body segments of the source motion to the target character, while using generalized inverse kinematics to solve all the corresponding constraints. This idea of modeling the topology between body segments has been extended by introducing an interaction mesh [Ho et al. 2010[Ho et al. , 2014. Recent works introduced the concept of egocentric plane to ensure that the instantaneous separating plane between each pair of body parts is transferred between the source and target motion [Molla et al. 2018]. ...
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... Recent research efforts have also proposed attractive methods based on topological coordinates for the (offline) retargeting of complex multi-agents interactions. However these methods are either costly [18] or not suited for online performance animation [19]. Likewise, techniques allowing the deformation transfer between surface meshes are also still far from realtime [20], [21]. ...
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... Finally, position constraints should prevent body overlap or other appearances that do not conform to the objective world. Researchers have proposed topology coordinates [14,15] and interaction mesh [13,16] to solve these problems in close interaction [6,17,47]. In our work, the proposed model mainly solves the problems of stability and human dynamics of the generated animation as well as adaptability with various interactions. ...
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