  Skeleton creation is an important phase in the character animation pipeline.
However, handcrafting skeleton takes extensive labor time and domain knowledge.
Automatic skeletonization provides a solution. However, most of the current
approaches are far from real-time and lack the flexibility to control the
skeleton complexity. In this paper, we present an efficient skeletonization
method, which can be seamlessly integrated into the sketch-based modeling
process in real-time. The method contains three steps: local sub-skeleton
extraction; sub-skeleton connection; and global skeleton refinement. Firstly,
the local skeleton is extracted from the processed polygon stroke and forms a
subpart along with the sub-mesh. Then, local sub-skeletons are connected
according to the intersecting relationships and the modeling sequence of
subparts. Lastly, a global refinement method is proposed to give users
coarse-to-fine control on the connected skeleton. We demonstrate the
effectiveness of our method on a variety of examples created by both novices
and professionals.
