We present CharacterMixer, a system for blending two rigged 3D characters with different mesh and skeleton topologies while maintaining a rig throughout interpolation. CharacterMixer also enables interpolation during motion for such characters, a novel feature. Interpolation is an important shape editing operation, but prior methods have limitations when applied to rigged characters: they either ignore the rig (making interpolated characters no longer posable) or use a fixed rig and mesh topology. To handle different mesh topologies, CharacterMixer uses a signed distance field (SDF) representation of character shapes, with one SDF per bone. To handle different skeleton topologies, it computes a hierarchical correspondence between source and target character skeletons and interpolates the SDFs of corresponding bones. This correspondence also allows the creation of a single "unified skeleton" for posing and animating interpolated characters. We show that CharacterMixer produces qualitatively better interpolation results than two state-of-the-art methods while preserving a rig throughout interpolation.

翻译：我们提出CharacterMixer系统，用于融合具有不同网格和骨架拓扑结构的两套已装配三维角色，并在整个插值过程中保持骨架结构。该系统的创新特征在于能够对运动状态下的角色进行插值。插值是重要的形状编辑操作，但现有方法在应用于已装配角色时存在局限：它们要么忽略骨架（导致插值后的角色无法进行姿态调整），要么使用固定骨架和网格拓扑。为处理不同网格拓扑，CharacterMixer采用基于骨骼的有符号距离场（SDF）表示角色形状；为处理不同骨架拓扑，它通过计算源角色与目标角色骨架的层级对应关系，对相应骨骼的SDF进行插值。这种对应关系还允许创建统一的"联合骨架"，用于插值后角色的姿态设定与动画制作。实验证明，CharacterMixer在定性插值效果上优于两种现有先进方法，且能全程保持骨架结构。