Waterfall Entry
Staggered ARRIVAL cascade: words/elements whip in from below (one consistent direction), each starting before the previous settles — an accelerating wave that resolves into a composed layout. Title cards, segment openers, list/feature intros.
This is an in-scene arrival, not a seam. Its seam sibling is the waterfall CUT
(cut-the-curve doctrine skill, seams/waterfall-cut.md); do not mix their rules:
| Entry (this rule — arrival) | Waterfall Cut (seam) | |
|---|---|---|
| Opacity | BINARY 0→1 via tl.set at entry — never fade |
ignites at 0.35 mid-path — the fade IS the velocity trick |
| Axis default | Y, from below | X, riding the current |
| Outgoing side | none | words ramp out on mirrored power4.in |
Choreography
- Overlap, don't queue — next element starts within ±2 frames of the previous settling; gaps SHRINK across the cascade; the last element snaps.
- Velocity varies by weight — heavy/anchor elements travel further and longer; light words/punctuation snap in tight:
| Parameter | Anchor/heavy | Normal word | Light/punctuation |
|---|---|---|---|
| Y offset | 60–80px | 40–50px | 30–48px |
| Duration | 0.16–0.20s | 0.13–0.16s | 0.10–0.13s |
| Overlap | 0–2f gap | 1f overlap | 1–2f overlap |
- Ease
power4.out(expo.outfor extra snap); never.inOuton an entry. - One direction per cascade.
- Split the FINAL word into fragments to extend the climax; fragments travel further.
- Post-settle, the group usually slides to make room for the next beat — that's nudge-curve.md.
JS
Each element: tl.set (instant reveal + offset) then tl.to (whip to rest).
nextStart = prevStart + prevDuration − (overlapFrames × F); +overlap = cascade,
−overlap = deliberate gap. CSS: elements start opacity: 0; display: inline-block.
var F = 1 / 60;
var t0 = 0.1;
// anchor (heaviest): biggest travel, longest settle
tl.set("#el-1", { opacity: 1, y: 80 }, t0);
tl.to("#el-1", { y: 0, duration: 0.18, ease: "power4.out" }, t0);
// normal word: 2 frames after the anchor finishes
var t1 = t0 + 0.18 + 2 * F;
tl.set("#el-2", { opacity: 1, y: 45 }, t1);
tl.to("#el-2", { y: 0, duration: 0.15, ease: "power4.out" }, t1);
// light word: 1 frame BEFORE the previous finishes (overlap)
var t2 = t1 + 0.15 - F;
tl.set("#el-3", { opacity: 1, y: 40 }, t2);
tl.to("#el-3", { y: 0, duration: 0.14, ease: "power4.out" }, t2);
// split final-word fragments: tightest overlap, extra travel (lighter)
var t3 = t2 + 0.14 - F;
tl.set("#frag-a", { opacity: 1, y: 70 }, t3);
tl.to("#frag-a", { y: 0, duration: 0.16, ease: "power4.out" }, t3);
var t4 = t3 + 0.14 - F;
tl.set("#frag-b", { opacity: 1, y: 70 }, t4);
tl.to("#frag-b", { y: 0, duration: 0.15, ease: "power4.out" }, t4);
// punctuation: lightest, fastest
var t5 = t4 + 0.13 - 2 * F;
tl.set("#dot", { opacity: 1, y: 48 }, t5);
tl.to("#dot", { y: 0, duration: 0.12, ease: "power4.out" }, t5);Anti-patterns
| Don't | Instead |
|---|---|
| Queued entries (each waits for the previous to settle) | Overlap ±1–2 frames — the cascade is a wave, not a queue |
| Same offset/duration for every cascade element | Vary by weight: anchors travel further, punctuation snaps |
| Gradual opacity fade on an arrival | Binary 0→1 via tl.set — fading fights the snap (seam cuts fade; arrivals don't) |