3d animation artists

Abstract: Parametric human body models such as the Skinned Multi-Person Linear (SMPL) model provide compact representations of human shape and pose, but their reconstructions remain affected by both errors in estimated latent parameters and limitations in the decoder's expressive capacity. We propose a framework for refining these reconstructions by exploiting the geometric discrepancy between an initial decoded surface and a target mesh, without requiring vertex correspondences between them. The framework comprises three complementary approaches. Latent-VaRefine uses varifold-distance gradients to correct the estimated latent code while preserving the original parametric representation. Vertex-VaRefine processes multiscale varifold-gradient features with a DiffusionNet backbone to predict vertex displacements in a canonical pose, yielding an approximately pose-equivariant refinement pipeline. ElaOpt directly optimizes surface deformations under elastic regularization and normal-direction constraints.

Abstract: Text-to-motion models generate for the skeletons they were trained on, while a new character arrives as a skeleton file and nothing else. We study text-to-motion for skeletons that no training clip has used, with no clips of the character, no template, no retargeting and no fine-tuning. We present TopX, a 73M-parameter flow-matching transformer that generates joint rotations and a root trajectory for any kinematic tree from its tree, rest pose and joint names. Motion is normalised by the rest pose and the size of the skeleton, and the rest pose enters as a world-frame descriptor that does not depend on how the rig's author oriented each joint, with rest conventions randomised in training. Attention is factorised over the joints and the frames of a motion and carries a spatial--temporal encoding designed for skeleton graphs of any topology: queries and keys are rotated across joints by a heat-kernel coordinate of the skeleton graph, which is defined for every tree and does not change with the order of its joints or the eigenbasis of its Laplacian, and across frames by a rotary encoding of frame order. To measure what this buys, we build SkelShift: four motion corpora under one codec, 143,334 captioned clips on skeletons of 4 to 142 joints, from which 4,232 clips on 2,043 skeletons are held out by clip, rig, tree class or species and organised along topology, joint count, body plan, species and rig source, and scored by motion quality: Fréchet distances on public kinetic features and on kinematic descriptors, foot skating and ground contact. Against UniMate trained on the same clips, on test rigs without a training clip, TopX lowers the descriptor FID from 5.73 to 4.58 when UniMate's guidance is tuned for the kinetic FID, and the kinetic FID from 1.48 to 0.55 when it is tuned for the descriptor FID, also on motions no training skeleton performs; fewer of its frames sink below the ground.

Abstract: People communicate how things should move by combining words with demonstrations: "open it like this." We present an interaction technique that brings this expressive resource to conversational 3D authoring. Building on "Put-That-There," our system combines speech, pointing, and spatiotemporal demonstrations to specify editable behavior. A hand movement supplies evidence for a mechanism's axis, pivot, range, and pace; an animated preview makes the interpretation inspectable. Users refine behavior through further words or demonstrations, and the system can request a demonstration to clarify intent. In a twelve-participant study comparing three input configurations, our system achieved 89% participant-declared completion versus 47% with speech alone, had the highest observed match rates on six categorical accuracy measures and tied on two, and was preferred by nine participants. This work makes demonstration part of an ongoing authoring conversation: behavior can be shown, inspected, and revised.