2D characters

Read the brand's mascot rules first (brands/<slug>/README.md, Mascot). A brand mascot is only drawn from the brand's own files; never redraw it from memory.

SVG rig (no designer file)

1. Draw the character as an inline <svg> from simple shapes in the brand colours. Name the parts: #body, #eyes, #mouth-closed, #mouth-open, #arm-l, #arm-r (any can be left out).
2. const c = SvgRig(svgEl) then chain: .idle(from, to), .blink([t…]), .talk(from, to), .wave(t), .hop(t).
3. Arms pivot at the inner, lower corner of the arm's box. If an arm swings off the body, set data-pivot="x% y%" on it.
4. Speaking a voiceover: lip sync (next section). Without Rhubarb, a cheaper lip flap: word starts from scripts/transcribe.sh audio/vo.wav audio/vo passed as .talk(0, 0, { beats: [...] }).
5. Reuse: once a character is approved, save its SVG in brands/<slug>/assets/characters/ and add it to the brand README.

Lip sync (a character speaks the voiceover)

1. Cues per VO line: scripts/lipsync.sh audio/vo.wav audio/vo.visemes.json --dialog audio/vo.txt (Rhubarb Lip Sync; install note in the script). Use the approved script as the dialog file. Seconds for each line.
2. Load <script src="../audio/vo.visemes.js"> and <script src="/engines/lipsync.js"> in the composition.
3. SVG rig: draw the mouth shapes as #mouth-A … #mouth-H, with #mouth-closed (or #mouth-X) as the resting mouth. A (lips pressed), B (slightly open, teeth), C (open), D (wide open), E (O), F (OO) carry most of it; G (F/V) and H (L) fall back to A and C if not drawn. Then .lipsync(LipSync.cues("vo.visemes"), { offset: <VO start> }), one call per line. Use .talk() or .lipsync() for a line, not both. Example: examples/engines-demo/index.html.
4. Mascot that only exists as an image (a PNG from the brand): LipSync.mountMouth(wrapper, { cx, cy, w, aspect, shapes: LipSync.mouthSet({ ink, cover }) }) draws a mouth over it (cover = the face colour, hiding the image's own mouth while talking; at rest the image's mouth shows). cx, cy, w are fractions of the image: measure once, check stills at a few cues, and keep the numbers in the brand README (Mascot). Then LipSync.addToTimeline(Studio.tl, cues, mouth, { offset }).
5. A drawn mouth on a brand's mascot is new artwork: the brand owner approves it before anything with it is published.
6. Keep the face alive while it talks: a blink every 2–4 s, a small nod on stressed words. LipSync.talking(cues, t, offset) says when the character is speaking.
7. QA: stills at a few cue times next to the cue file (does each mouth match the sound?), then one listen with the mix.

Rules and the 3D side: engines/README.md, Lip sync.

Lottie (designer file)

Studio.lottie(el, "/brands/<slug>/assets/lottie/<file>.json", { start, loop, speed }). Load /core/node_modules/lottie-web/build/player/lottie.min.js before the runtime. Check that the file uses no expressions or effects lottie-web cannot draw (render a still, compare with the designer's preview).

Rive (designer file)

riveLayer(el, "/brands/<slug>/assets/<file>.riv", { animation | stateMachine, start, loop, inputs }) from engines/rive.js. A timeline (animation) is posed straight from t. A state machine is stepped from 0 at the frame rate, so give its inputs as times: inputs: [{ at: 1.2, name: "wave" }, { at: 2, name: "mood", value: 2 }] (no value = trigger). Render a few stills in two orders (--workers 1, then --workers 2 with the times reversed) and check the md5s match. examples/reel-layer/rive.html is a working check page.

Character craft

• Anticipation before a move (a small squash before a hop), overshoot after (back.out).
• Blink every 2–4 s at irregular intervals. A still character looks dead.
• Hold poses long enough to read (≥ 0.4 s) on a phone.