#rigging

The method for hanging custom models off the player rig -- gadgets, backpacks, held items -- with three mount styles off one skeleton, and a live slider panel that dumps C#-ready constants for paste-back.

The method for making a procedurally-rigged NPC crumple via engine physics: author a physics skeleton in the vmdl, toggle Sandbox.ModelPhysics at runtime, and hand bone control back for stand-up. No authored collapse clips needed.

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

PhysicsShapeList + PhysicsJointList in the vmdl + ModelPhysics toggle. No collapse clips, no SetBoneTransform. On current builds ModelPhysics.PhysicsGroup reads NULL: enumerate ModelPhysics.Bodies directly and resolve bones by name→index.

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.

When a clip already poses hands in a grip and the prop moves/rescales, offset the rendered visual child instead of using IK or SetBoneTransform -- sequence-only rigs have no AnimGraph.

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.