Enhanced Direct Delta Mush

TL;DR

This paper extends the Direct Delta Mush skinning technique to handle non-rigid joint transformations, improving its applicability and stability for production use.

Contribution

It introduces an extension to Direct Delta Mush that incorporates non-rigid joint transformations and discusses practical implementation considerations.

Findings

Enhanced deformation quality with non-rigid transformations

Improved stability and computational considerations

Broader applicability for production environments

Abstract

Direct Delta Mush is a novel skinning deformation technique introduced by Le and Lewis (2019). It generalizes the iterative Delta Mush algorithm of Mancewicz et al (2014), providing a direct solution with improved efficiency and control. Compared to Linear Blend Skinning, Direct Delta Mush offers better quality of deformations and ease of authoring at comparable performance. However, Direct Delta Mush does not handle non-rigid joint transformations correctly which limits its application for most production environments. This paper presents an extension to Direct Delta Mush that integrates the non-rigid part of joint transformations into the algorithm. In addition, the paper also describes practical considerations for computing the orthogonal component of the transformation and stability issues observed during the implementation and testing.