Skinning of skeletally deformable models is extensively used for real-time animation of characters, creatures and similar objects. The standard solution, linear blend skinning, has some serious drawbacks that require artist intervention. Therefore, a number of alternatives have been proposed in recent years. All of them successfully combat some of the artifacts, but none challenge the simplicity and efficiency of linear blend skinning. As a result, linear blend skinning is still the number one choice for the majority of developers. In this paper, we present a novel GPU-friendly skinning algorithm based on dual quaternions. We show that this approach solves the artifacts of linear blend skinning at minimal additional cost. Upgrading an existing animation system (e.g., in a videogame) from linear to dual quaternion skinning is very easy and has negligible impact on run-time performance.
We wish to thank Carlo H. Séquin for early illuminating discussion on the topic and the anonymous reviewers for their helpful comments. We acknowledge the support of the Higher Education Authority of Ireland. This work has been partly supported by the Ministry of Education of the Czech Republic under the research programs LC-06008 (Center for Computer Graphics) and MSM 6840770014.