Maya animation (animator)
Expert animation means every frame is a choice: poses that read as drawings from the camera, holds and snaps placed on purpose, designed spacing, weight shown by resistance and a caught stop. Work big to small (story, body, face, detail); never add detail to a stage that does not read yet. An agent cannot scrub, so it measures (world and screen tracks, spacing, holds, contacts, a ballistic fit, overlap lags), then looks at a playblast or a headless sheet before calling anything done. If a sibling skill named here is missing from your available skills, ask the user to install it (npx skills add scenario-labs/skills --skill <name>); unattended, proceed from tool schemas and flag the gap.
REQUIRED BACKGROUND: scenario-maya-expert (execution channel, review loop, 2027 version traps).
Toolkit: scripts/mx_anim.py. Its analysis and image layer is pure Python and ran offline.
Stance (the expert delta)
- Pick the workflow per shot; blocking ends when the information is in. Neistadt: pose to pose for acting, straight ahead or extremes for flow; blocking is done when all five key categories exist (main, anticipation, overshoot and follow-through, breakdown, hold). Elver splines physical shots from the start; Camporota proves timing on two boxes first.
- Maya is "the worst in-betweener in the world" (Newman). Feed it keys: ones on fast actions, 2 to 4 frames apart on slow parts. Spline readiness is a test: spline the range, play; mush means back to stepped with more poses. Native Set Key reshapes neighboring curves (Wade): insert keys, prove it with a curve diff, and share keys across every control before splining.
- Weight is resistance, then release, then a caught stop. Wade: show what the character is up against (a delay, acceleration from rest) before its strength; strength is a frame count. Elver: more up and down reads as a balloon, not weight; weight is a fall caught abruptly, a bigger hold in the squash, residual jiggle. Heavy air is gravity-true [added physics]; Wade's weighted apex adds hang, for light or cartoony bodies.
- Feet and spine sell every weight shift (jump, hop, landing, lift). Camporota: animate the foot roll in every crouch, it sells the compression; in a big drop the spine drags behind the hips and only the arms drop; first passes overdo the anticipation, so dial it back; a touch-down goes flat "almost in one frame". Elver: on the first airborne frame the toe tip points back to where it left the ground.
- Judge in camera space, at speed. Elver: a motion trail can show a perfect 3D arc that fails on screen. Lazare: the eye goes to the biggest motion, so the non-focus character stays "appropriately still". Project tracks through the shot camera; read the playblast before any metric.
- The base layer is the animation; mocap is precious. Newman: a layer is a time-boxed experiment with marker keys and a protective key; never clean curves on it, merge with Smart Bake, then clean (Elver: only a late global note or an additive tremble, then bake). On mocap fix only the defect asked for, or the cascade ends "not hand key and not mocap"; after a merge, Euler filter, then delete keys down to extremes.
- Lip sync animates sounds, not words. Santos: jaw only first (the muppet pass), then the big five (jaw, two corners, top and bottom lip) for 90%; lead by place of articulation, bilabials on the frame. Lazare: shift every mouth key 1 to 2 frames earlier only when the whole line plays late.
- Polish is triage; review is top down. Elver ranks the notes, spends on the ones that pay, owns every contact frame. Newman grades Intent, Mechanics, Performance, Integration; a playblast does not prove game feel.
Establish first
| Input | Why it changes the plan | Default when the brief is silent |
|---|---|---|
| Style and destination | squash, stops, closeness to reference: cartoony pushes; live action needs pose squash and no dead stops (Elver); VFX stays near reference (Neistadt) | realistic feature quality |
| Frame rate | timing numbers, currentUnit | 24 fps (film) |
| Weight and strength | frames of resistance and of overcome (Wade: decide both numbers first) | heavy: resistance beat of 2+ frames, no hang |
| Rig | control names, IK/FK, spaces, foot roll attribute (map once with listAttr(keyable=True)) | hands in IK, no IK/FK or space switches inside a shot (Newman) |
| Camera | a locked shot camera is the only judge; games also need every angle and the engine | build the shot camera, lock it |
| Reference, audio | landmarks (contacts, takeoff, apex, landing, blinks, darts) give rhythm, then push (Neistadt) | beat list from the brief |
| Game metrics | speeds and heights agreed in round numbers before animating (Newman); root motion or in place (Epic) | in place, metrics sheet requested |
Workflow
- Plan in numbers. Beats with frames, the leading part per beat, key categories, contacts, windows (crouch, push, air, impacts), style;
A.store_plan(plan). Physical shots:A.air_frames(rise, drop)budgets the air. Dialogue: phrases with subtext and an action verb, ruled sounds (M, B, P, F, V, L, T, D), 2 to 4 tentpoles (Santos, Wade). GATE: frame counts add up. - Set up. fps, range, sound, shot camera locked; query the tangent defaults (2027 notes). GATE:
mx_validate.validate(profile="shot", rules={"fps": 24})has no fail. - Proxy pass (big, fast or camera-bound moves).
A.proxy_boxes(), key translate and lean, air withA.ballistic_keys(), rotation 1 to 2 frames behind (Camporota). The first anticipation is usually too big:A.scale_curve(root, "translateY", 0.8, rest_y, time=crouch). GATE:A.evaluate_gates()on the proxy (ballistic, catch, resistance, push_fastest);proxy_curves.pnglooked at. - Blocking, stepped.
A.set_key_defaults("blocking");A.key_pose(pose, f, fill=ctrls)keys every control on every pose; passes: main, anticipations, overshoots, breakdowns (favor a neighbor, never 50/50), holds (A.key_hold());A.share_keys(ctrls). Never act from the neutral rig pose (Neistadt). Crouch poses: foot roll keyed, spine dragging, arms hanging (Camporota). GATE: every key category present; stepped playblast (GUI) ortracks.png; write the story it reads, then check silhouettes. - Spline pass 1, the core.
snap = A.snapshot(ctrls)(the buffer curve);A.to_spline()on COG, spine, legs only; face, eyes, fingers stay stepped (Camporota, Santos). Air gravity-true; broken tangent into a hard landing (Newman); planted feet flat. Mush:A.restore(snap), add poses. Every later key:A.insert_key(), thenA.curve_diff()on sampled snapshots is ok outside its two segments (P4). GATE:A.run_gates(plan)ballistic, hang, catch, slide, penetration, foot_roll, spine_drag, heel_to_flat pass; noA.overshoots()through holds. - Spline pass 2, overlap. Arms, head, secondary: correlated chains edited together first (Newman), then
A.offset_keys()by 1 to 2 frames down the chain. GATE:overlaplags not all zero;pose_to_pose_telllow; tracks clean in camera. - Face, if the shot has one. Body first, then the mask (eyes, brows), then the mouth: muppet jaw keyed at
A.mouth_keys(phonemes), big five, tongue, connection byA.copy_curve()(nostrils 1 frame behind the corners, dampened). Eyes linear, 2-frame darts; blinks close faster than they open. GATE:A.jaw_report(),A.lip_lag()againstA.audio_envelope(),A.blink_report(),A.transitions(); close-ups on tentpoles. - Polish, by triage. Fix the top-ranked notes, one section at a time. Contacts and fast moves on ones; peel-off on every takeoff; impacts get a pushed squash and a bigger hold; pops become 3 frames on an arc plus an overshoot;
A.retime()tightens a section; moving holds; a motion-blurred render before final (all Elver). GATE: every gate passes (peel_off, impact_hold included), layers merged, no sub-frames, Euler filtered, critique.md on the final playblast.
Variants. Cycle: poses every 3 frames, loop with A.cycle() before polish, offsets inside the cycle keep the period. Game clip: metrics, A.cycle_speed(), loop seam, root rules, then scenario-maya-pipeline-scripting. Mocap: procedures P12; retarget: P13; heavy interactions: P9.
Numbers
| Value | Relative to | Source |
|---|---|---|
| Gravity 1.703 cm/frame^2 (981/576) | 24 fps, scene in cm | physics [added] |
| Walk keys every 3 frames: contact 1, down 4, pass 7, up 10, contact 13; loop 1 to 25 | 24-frame cycle | Camporota |
| Touch-down to flat foot about 1 frame, at most 2; walk arm offsets 0, 1, 2, head 1 | every step and landing | Camporota; body digest |
| Rotation 1 to 2 frames behind translation | proxy and body | Camporota |
| Keys on ones on fast actions; 2 to 4 frames apart on slow ones | blocking | Newman |
| Blink close 2 / open 4 (or 3 / 5; big eyes one more) | frames | Elver |
| Eye dart 2 frames, linear; brows lead lids by 1 to 2, never 5 | frames | Elver |
| Snappy move: 3 frames on an arc plus a small overshoot, never 1 | frames | Elver |
| Global lip shift 1 to 2 frames earlier; opens near full on frame 1 | when late at speed | Lazare |
| Big five = 90% of lip sync; jaw plus corners 50 to 60% | controls | Santos, Elver |
| Game speeds: walk 2, run 4 to 6, sprint 12 to 15 m/s | stylized player | Newman |
Playblast default scale 0.5: pass percent=100 | active view | Maya 2027 Help |
Quality gates
Measurable (A.run_gates(plan); pure logic A.evaluate_gates), for any jump, hop, landing or weight shift in the plan: fps; heavy air g_ratio 0.8 to 1.25, hang excess at most 1 frame, constant horizontal speed; catch (60%+ of the fall speed gone in 2 frames, decel shorter than recovery), then a 3+ frame hold at the bottom; push fastest; heavy resistance beat of 3+ still frames; every crouch: foot roll moves, spine lags the hips; touch-downs flat within 2 frames; lift-off toe within 30 degrees of the takeoff spot; planted feet at most 0.2 cm/frame, penetration under 0.5 cm; pre-landing stretch; no pops outside impacts; overlap lags; moving end hold; tell under 90% after splining; no sub-frames; no layers at polish. [added] thresholds are toolkit defaults.
Visual: A.review_images(plan, out) (headless: curves.png stacked lanes, tracks.png camera-space tracks with onion-skin poses); in the GUI A.playblast_pack() (shot camera plus a no-lights silhouette) and a stepped-preview playblast. Read frames in time order; write the first-view read before the numbers (critique.md).
Common mistakes
| Mistake | What it looks like | Fix |
|---|---|---|
| Splining before the poses are in | mush, arms tweened through the body | A.restore(snap), add breakdowns stepped |
| Even spacing, whole body on the same frames | floaty, "hitting poses" | favor neighbors, holds, offset_keys down the chains |
| First-pass anticipation kept | the crouch upstages the action | A.scale_curve(..., time=crouch) about the rest value |
| Torso locked to the hips, arms swung back in the crouch | stiff, generic anticipation | spine drags behind the hips, only the arms drop |
| Feet flat in the crouch, pointing forward at takeoff, slow to flatten on landing | weak compression, no push, slapping feet | foot roll; toe aimed back at the takeoff spot; flat within 1 to 2 frames |
| Stylized hang on a heavy body | floaty apex | ballistic_keys, flat apex, broken contact tangent |
| No resistance before the effort | styrofoam weight | 2+ frames of strain before the push |
| Symmetric dip, or a bounce straight out of the squash | light landing | sudden catch, bigger hold, one overshoot, slow recovery |
S or bare setKeyframe on a splined curve | neighbors reshape, holds drift | A.insert_key, then A.curve_diff |
| Spline through a hold | drifting hold | key_hold pillars, flat or plateau sides |
| Arcs checked on a 3D trail | clean trail, broken arc on screen | camera_track pixel tracks |
| Lip sync keyed on the sound | late at speed | per-sound lead, then a global shift |
Handoffs
Receives from scenario-maya-rigging and scenario-maya-deformation: the rig referenced (never imported), validate(profile="rig") clean, the control list with IK/FK, space and foot roll attributes, a range-of-motion playblast. Rig problems (knee pop, flipping space) go back as a note with frames.
Delivers shots to scenario-maya-lighting-rendering: a new saved version, validate(profile="shot") clean, layers merged, helpers deleted (A.delete_helpers()), run_gates JSON with no fail, the final playblast the agent looked at, what was not verified. Game clips to scenario-maya-pipeline-scripting: skeleton baked per clip, clip names and ranges (bookmarks), root rule (in place or root motion), loop seam and speed reports.
Maya 2027 notes
- Default tangent: Auto Span (Legacy) on one doc page, Clamped on another: query
keyTangent(q=True, g=True, itt=True). Lock/Free Tangent Weight is now Tangent Length; Butterworth is Smooth Filter (Butterworth). - Time Slider > Enable Stepped Preview;
A.stepped_preview()is the scripted twin. Dope Sheet Time Snap is off since 2025.1 andscaleKeyleaves sub-frames:A.snap_subframes(). - Ghost Editor and Motion Trail Editor sit under Visualize; ghosting a skinned mesh needs Cached Playback (disabled by motion blur, Trax, classic dynamics).
- Playblast needs a model panel (GUI via mx_bridge); in mayapy use
review_imagesor Arnold stills. - Sequencer (ex Camera Sequencer): lock every camera. HumanIK bakes from its own window, not Bake Simulation. Time Editor clips never mix with animation layers. Blue Pencil replaced Grease Pencil.
References
references/expert-notes.md: principles and numbers by expert, timestamps, deciding conditions. Load to choose an approach or write notes.references/procedures.md: themx_animAPI and full procedures with test paths. Load before writing code.references/critique.md: review rubric (first-view read, four buckets), director lingo, note format. Load at every gate.references/gui-paths.md: menus, hotkeys, editor settings. Load for a computer-use agent or a human.references/sources.md: every source, credential, URL and best timestamp.
