Implicit curve oriented inbetweening for motion animation

While the parametric curve is overwhelmingly used in current character motion animation practice, the utilization of the implicit curve is recognized to be extremely potential for motion animation since the implicit surface have succeeded in such application as modeling, deformation and rendering within computer graphics and animation. In this paper, we advocate the use of implicit curves in motion animation. Implicit curves for task specification in motion animation is proposed and further explored in this paper. A planar implicit curve is used to represent the motion path while a speed profile curve is adopted to describe the motion timing. Then an approach and algorithm to motion inbetweening along implicit curves is proposed. Based on the motion path and motion speed, curve oriented inbetweening technique is utilized to generate inbetween position sequences in Cartesian space from which frame inbetweens in parametric space for animation are obtained by inverse kinematics.