A sketch-based interface to modify and reproduce motion sequences

We present a sketch-based user interface, which was designed to help novices to create 3D character animations by multi-pass sketching, avoiding the ambiguities usually present in sketch input. Our system also contains sketch-based editing and reproducing tools, which allow paths and motions to be partially updated rather than wholly redrawn; and graphical block interface permits motion sequences to be organized and reconfigured easily. A user evaluation with participants of different skill levels suggest that novices using this sketch interface can produce animations almost as quickly as users who are experienced in 3D animation.