Rigging

rigging

Purpose

Turn a model into a puppet the animator can perform with: one control = one job, deformation that holds volume, a facial system when the character acts, and a sign-off test before any animation.

Scope

D48–D60, D63, D131, Depth 19/20/28. Facial animation and lip sync timing are animation (D61/D62) but this skill builds the face machine.

Activation Conditions

• Rig, armature, IK, FK, weights, skinning, drivers, shape keys, facial rig, eye aim, mocap retarget, foot roll, space switch
• Feedback from animation: controls unusable
• Use rigging

Non-Activation Conditions

• Topology still failing bend tests (→ modeling first)
• Acting/performance (→ animation)
• Soft-body jiggle as physics (→ simulation) unless a jiggle rig (28.10)

Instructions

1. Do not rig a non-final mesh for final animation (economy rule 5). Test-rig at blockout is OK.
2. Pick rig type (decision 5.4) and facial method (5.12).
3. Build order (5.19 / Ch 6):
   1. Skeleton placement & roll (D49). Bone Collections (4.x). Consistent orientations. Avoid gimbal traps.
   2. Deform bones vs control bones vs mechanical (D50). BBones for spines/tails.
   3. IK limbs with pole targets (D51); FK for arcs (D52); IK/FK switch without pops.
   4. Spine/torso (28.3), shoulders/clavicles (28.4), foot roll (28.1), hands (28.2).
   5. Constraints (D53): Copy, Limit, Damped Track, Child Of, Armature, Stretch To, Floor.
   6. Drivers (D54) where automation earns its keep (Ch 19 recipes) — not for everything.
   7. Controllers with custom shapes (D55). Readable in silhouette.
   8. Bind (D57) + weight paint (D56). Auto weights as start, not finish.
   9. Deformation tests (D58). Volume loss → correctives (D59) or topology feedback.
   10. Facial (D60): jaw, brows, eyes, lips. Shape-key library (19.2, 60+ keys) for realistic; bones for stylized; mixed for creatures.
   11. Eye systems (D63): gaze aim, eyelids follow, pupils, blink. Eyes precede head.
   12. Specials: mechanical (28.6), wings (28.7), tail/tentacle (28.8), multi-leg gait (28.9), jiggle/squash (28.10), space switching (28.11).
4. Mocap (D131 / Ch 20): acquire → cleanup → retarget to this rig; still hand-key face/hands/eyes for hero (5.14).
5. Run templates/rig-signoff.md. Animator must pose an acting beat without fighting the rig.
6. Separate rig file from shot files (D123). Link + overrides.

Procedures

IK → Leg IK → Foot IK → Foot Controller

Pivot, orientation, rotation limits, pole vector, heel roll, ball, toe, bank.

Facial rig → Control map → Expression

Controls drive keys or bones. Phoneme set must exist before lip sync animation.

Eye system → Gaze → Hierarchy

Aim bone at target; eyelids; saccades are animated later; pupil dilation shape key or scale.

Space switching

Grab/drop props: world space ↔ hand space via Child Of influence or space-switch custom property. See 28.11.

Decision Logic

• Rig only what the animation needs. Background: 3–5 face keys.
• If deformation fails: topology first (modeling), weights second, correctives third.
• Rigify/Auto-Rig Pro are accelerators after you understand the graph (D134 rule).

Inputs

• Deformation-ready mesh, joint ranges (Ch 16), sheet (expression range), locomotion class, whether dialogue, prop interactions

Outputs

• Control rig + deform rig
• Weight groups
• Facial system
• Sign-off report
• Shared state: locks.rig

Tools

Armature, Pose Mode, constraints, drivers, shape keys, Rigify (built-in), optional Auto-Rig Pro. Ch 19 driver language. Ch 28 node cards.

Constraints

Never animate on a moving rig target. Never leave deform bones as the animator interface. Never skip pole targets on IK legs. Bone Collections replaced bone groups in 4.x.

Edge Cases

• 6-legged crystal creature: per-leg IK + gait driver; no Hollywood face unless it acts.
• Mech: no soft deform; pistons and limit rot.
• Stretchy cartoon: Stretch To + squash root; topology must support it.

Failure Modes & Fixes

Dependencies

• NEEDS topology (modeling)
• Consumes anatomy ranges (sculpting-anatomy)
• DRIVES animation
• ⇄ animation feedback
• Facial keys Depth 19; mocap Depth 20

Related Skills

modeling, animation, costume-groom, sculpting-anatomy, decision-engine

Delegation Rules

• Topology fix → modeling (do not hide with weights)
• Performance → animation
• Cloth/hair bind meshes → costume-groom
• Driver recipes beyond 12 → read Ch 19; don't invent fragile Python drivers when a constraint works

Examples

• Biped hero: IK/FK arms/legs, foot roll, 3-bone BBone spine, clavicles, 60-key face, eye aim, sign-off squat+reach+dialogue.
• Dragon: wing fold + IK tip, tail BBone, 4-leg IK, no lips visemes if it doesn't speak.

Required Knowledge / Context

• knowledge/domains/ch06-rigging.md
• knowledge/domains/ch07-facial.md
• knowledge/depth/ch19-shapekeys-drivers.md
• knowledge/depth/ch20-autorign-mocap.md
• knowledge/depth/ch28-advanced-rigging.md

References to Shared Resources

• templates/rig-signoff.md
• decision-engine 5.4 5.12 5.14 5.19