Geodesic Binding for Degenerate Character Geometry Using Sparse Voxelization
We propose a fully automatic method for specifying influence weights for closed-form skinning methods, such as linear blend or dual quaternion skinning. Our method is designed to work with production meshes that may contain non-manifold geometry, be non-watertight, have intersecting triangles, or be comprised of multiple connected components. Starting from a character rest pose mesh and skeleton hierarchy, we first voxelize the input geometry. The resulting sparse voxelization is then used to calculate binding weights, based on the geodesic distance between each voxel lying on a skeleton "bone" and all non-exterior voxels. This yields smooth weights at interactive rates, without time-constants, iteration parameters, or costly optimization at bind or pose time. By decoupling weight assignment from distance computation we make it possible to modify weights interactively, at pose time, without additional pre-processing or computation. This allows artists to assess impact of weight selection in the context in which they are used.
PaperOlivier Dionne and Martin de Lasa, Geodesic Binding for Degenerate Character Geometry Using Sparse Voxelization, IEEE Transactions on Visualization and Computer Graphics (TVCG)
We thank reviewers for valuable feedback and suggestions. Thanks to Alec Jacobson, Daniele Panozzo, and other members of the libIGL team for their Bounded Biharmonic Weights implementation. Special thanks to Martin Bisson for many insightful conversations and suggestions regarding use of winding numbers and potential algorithm optimizations.