Real-Time Motion Transition by Example

Abstract

Motion transitioning is a common task in real-time applications such as games. While most character motions can be created a priori using motion capture or hand animation, transitions between these motions must be created by an animation system at runtime. Because of this requirement, it is often difficult to create a transition that preserves the feel that the actor or animator has put into the motion. An additional difficulty is that transitions must be created in real-time. This paper provides a method of creating motion transitions that is both computationally feasible for interactive speeds, and preserves the feel of the original motions. To do this, we build the transition from both a procedural motion and a motion segment taken from the motions being transitioned between.

Precomputed optimal one-hop motion transition for responsive character animation

“…Motion transition is a primitive problem in interactive character animation, and researchers have worked on this and related topics for decades (e.g., [1,6,9,13,16,23,29,33,37]). Our proposed framework can be seen as a variant of the motion-graph-based approach [1,16,23], in that we consider graphs with a specific structure (i.e., one-hop graphs) and use techniques developed in that context.…”

“…Interactive motion transitions Several previous methods specifically focused on interactive motion transitions (e.g., [2,6,13,29]). Among them, the method by Ikemoto et al [13] is probably the most similar to ours.…”

“…Choice of distance function Our current implementation uses a distance function proposed by Kovar et al [16] which has been used in many follow-up works [6,15,17]. It spatially aligns the two motion fragments to be blended by finding an optimal 2D rigid transformation (i.e., horizontal translation and the yaw rotation) in the least-squares sense, and then it calculates the sum of the distances between corresponding points on the character's body for every pair of frames.…”