Motion editing with spacetime constraints

TLDR

The paper proposes a method to edit existing motion to meet new requirements while preserving original quality, addressing challenges in constraint formulation, solver speed, and user interface. The method uses a spacetime constraints solver that evaluates positions across the entire motion, implemented in a prototype system that enables interactive editing of articulated 3D characters on personal computers. The prototype demonstrates that users can directly manipulate character positions interactively, confirming the feasibility of the approach. Classification codes I.3.7, I.3.6, G.1.6 and keywords Spacetime Constraints, Motion Displacement Mapping.

Abstract

In this paper, we present a method for editing a pre-existing motion such that it meets new needs yet preserves as much of the original quality as possible. Our approach enables the user to interactively position characters using direct manipulation. A spacetime constraints solver finds these positions while considering the entire motion. This paper discusses the three central challenges of creating such an approach: defining a constraint formulation that is rich enough to be effective, yet simple enough to afford fast solution; providing a solver that is fast enough to solve the constraint problems at interactive rates; and creating an interface that allows users to specify and visualize changes to entire motions. We present examples with a prototype system that permits interactive motion editing for articulated 3D characters on personal computers. I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism – Animation; I.3.6 [Computer Graphics]: Methodology and Techniques Interaction Techniques; G.1.6 [Numerical Analysis]: Optimization. Spacetime Constraints, Motion Displacement Mapping.