#animation

Deriving a visual's facing from horizontal velocity causes 180-degree snaps on any momentum reversal — lock facing to an attach-time azimuth for pendulums and oscillators.

Set Sequence.Blending = true once — per-clip fade_in/fade_out times in the vmdl shape the blend; no AnimGraph required.

Foot-slide happens when PlaybackRate is tied to movement top speed instead of the clip's own authored stride distance.

Converting euler poses per-key can land on q vs -q — the interpolation takes a violent 360-degree detour. Negate the quat if dot(prev, new) < 0.

PhysicsShapeList + PhysicsJointList in the vmdl + ModelPhysics toggle — no collapse clips, no SetBoneTransform.

Transfer rest-delta rotations parent-relative (not world) — avoid the forward-hunch bug and never transform_apply scale on Mixamo armatures.

Bone-heat auto-weights fail on AI meshes — use scripted geodesic (along-surface) weights, then FBX + animated vmdl.

Model compiler rewrites upper_arm.L → upper_arm_L; physics KV3 that still says .L makes limb bodies unknown while the torso works.

Default −Z/Y axes, bake_space_transform, no leaf bones, X/Z bone axes, mesh FBX + per-clip armature FBX; scale via ScaleAndMirror 0.3937.

SetIk is AnimGraph-gated; SetBoneTransform is unsound on clip-keyed bones — use proxy props, whole-visual motion, or commit to AnimGraph.