# Direct Manipulation of Interactive Character Skins

Geometry deformations for interactive animated characters are
most commonly achieved using a skeleton-driven deformation technique
called linear blend skinning. To deform a vertex, linear blend
skinning computes a weighted average of that vertex rigidly transformed
by each bone that inuences it. Authoring a character for
linear blend skinning involves explicitly setting the weights used to
compute deformed vertex positions. This process is tedious, repetitive,
and frustrating not only because the deformed vertex positions
are not intuitively related to the vertex weights, but also because the
range of possible deformations is unclear. In this paper, we present
a method that lets users directly manipulate the deformed vertex positions
in a linear blend skin. We compute the subspace of possible
deformed vertex positions, display it for users, and let them place
the vertex anywhere in this space. Our algorithm then computes the
correct weights automatically. This method lets us provide a skin
editing interface that gives users as much direct control as possible
and makes explicit what deformations are possible.

## Images and movies

## BibTex references

@InProceedings{MTG03, author = "Mohr, Alex and Tokheim, Lucas and Gleicher, Michael", title = "Direct Manipulation of Interactive Character Skins", booktitle = "Proceedings of the Symposium on Interactive 3D Graphics", month = "apr", year = "2003", url = "http://graphics.cs.wisc.edu/Papers/2003/MTG03" }