iSlerp: An Incremental Approach to Slerp

Abstract

In this paper, an incremental quaternion-interpolation algorithm is introduced. With the assumption of a constant interval between a pair of quaternions, the cost of the interpolation algorithm is significantly reduced. Expensive trigonometric calculations in Slerp are replaced with simple linear-combination arithmetic. The round-off errors and drifting behavior accumulated through incremental steps are also analyzed.