Files
hyperframes/skills/hyperframes-animation/rules/center-outward-expansion.md
T
WaterrrForever 853256403b feat(skills): c2v mining pass — 7 new blueprints, 10 new rules, compacted recipe corpus (#2680)
* feat(skills): c2v mining pass over animation blueprints and rules

Compacts ~45 existing animation rules/blueprints into tighter recipe form
(net -3.4k lines) and adds 17 mined from the c2v corpus:

- 7 blueprints: agent-progress-theater, camera-journey, fixed-anchor-cycle,
  panel-edit-live-sync, prompt-type-submit-generate,
  transcript-scroll-artifact-reveal, zoom-out-workspace-reveal
- 10 rules: 3d-camera-flight, anchored-layout-expand, chart-scrub-readout,
  chromatic-glitch, control-target-sync, cursor-drag, gradient-text-sweep,
  multi-cursor-choreography, particle-burst, theme-crossfade-morph






Both indexes updated.

* feat(skills): sync product-launch script bank with mined blueprint roles

The role->blueprint script bank in product-launch-video/story-design.md is
kept 1:1 with blueprints-index role declarations, which the c2v mining pass
expanded. Adds the 25 missing entries (script-shape descriptor + example
lines + pattern): 13 for the 7 new blueprints, 12 for role widenings on 7
existing ones (cursor-ui-demo, dataviz-countup, titlecard-reveal, et al.),
and states the 1:1 sync contract in the bank's intro.

* docs(skills): cover constellation-hub scatter-drift variant in the script bank

Review follow-up on #2680: the SOCIAL_PROOF constellation-hub entry
patterned only the orbit shape; the c2v pass added a scatter-drift
end-card variant with the opposite geometry (no hub, no ring). Adds an
example line and extends the pattern so a scatter-drift beat's VO isn't
steered toward the orbit shape.
2026-07-21 17:28:55 +08:00

89 lines
4.2 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
---
name: center-outward-expansion
description: Elements start clustered at screen center and expand outward to their final positions, driven by a shared progress value.
metadata:
tags: expansion, scatter, center, reveal, layout, sync, burst
---
# Center-Outward Expansion
Elements begin at one shared center point and radiate outward to their final positions — the entry beat itself, or motion driven by another animation's progress (a counting number, a beat). Flat 2D cousin of [depth-scatter-assemble.md](depth-scatter-assemble.md) (per-element 3D cloud): here every element shares the SAME origin.
## How It Works
Each element carries its final offset as `data-target-x/y`. Its position lerps between center and target: `x = targetX × progress`. Self-centering is baked as `xPercent/yPercent: -50` so the tweened `x`/`y` are pure offsets from the stage center. Standalone burst = per-item staggered `fromTo`; driven burst = one shared proxy (see Variations).
## Recipe
```html
<!-- inside a standard scene clip (hyperframes-core) -->
<div class="burst-wrap">
<div class="burst-item" data-target-x="-360" data-target-y="-180">{itemA}</div>
<div class="burst-item" data-target-x="360" data-target-y="-180">{itemB}</div>
<div class="burst-item" data-target-x="0" data-target-y="360">{itemC}</div>
</div>
```
```css
.burst-wrap {
position: relative;
width: 100%;
height: 100%;
display: grid;
place-items: center;
}
.burst-item {
position: absolute;
top: 50%;
left: 50%; /* GSAP xPercent/yPercent -50 bakes the centering; x/y tween the offset */
will-change: transform;
}
```
```js
document.querySelectorAll(".burst-item").forEach((el, i) => {
tl.fromTo(
el,
{ xPercent: -50, yPercent: -50, x: 0, y: 0, scale: 0.6, opacity: 0 },
{
x: Number(el.dataset.targetX),
y: Number(el.dataset.targetY),
scale: 1,
opacity: 1,
duration: EXPAND_DUR,
ease: EXPAND_EASE,
},
ENTRY_AT + i * STAGGER,
);
});
```
## Variations
- **Synced to a driver (chord)**: when the burst shadows a counter / beat, drop the stagger and drive all items from ONE 0→1 proxy tween with the driver's exact duration AND ease; `onUpdate` writes `translate(-50%,-50%) translate(targetX*p, targetY*p)` per item — the two read as one beat.
- **Partially-spread start**: with 6+ items the full cluster piles up — start from `{ x: targetX * START_PROGRESS, ... }`.
- **Idle micro-float**: hand off to [sine-wave-loop.md](sine-wave-loop.md) after landing instead of freezing.
## Values
| token | range | notes |
| -------------- | -------------------- | ---------------------------------------------------------------- |
| ITEM_COUNT | 38 | > 8 = visual chaos mid-expansion; low counts want wider spread |
| EXPAND_DUR | 1.01.8s | must equal the driver's duration in the synced variant |
| EXPAND_EASE | `power3.out` default | `power2.out` gentler, `expo.out` dramatic stop; NEVER `in` eases |
| STAGGER | 0.040.08s | tighter = chord; looser = lazy arpeggio |
| ENTRY_AT | 00.5s | a beat of compositional quiet before the burst |
| START_PROGRESS | 00.5 | 0 = dramatic full cluster; ~0.3 avoids the pile-up |
## Critical Constraints
- **Tween `x`/`y` over the baked `xPercent/yPercent: -50`** — mutating `left`/`top` fights the centering and causes pixel jitter.
- **Out-easing only** — `in` easings read as items being sucked back mid-air.
- **No other absolute-positioned siblings inside `.burst-wrap`** — they'd steal the centered baseline.
- **❗ The burst IS the beat** — don't park a "real headline" label below it (the eye snaps to the label and ignores the burst). If a label is needed, reveal it post-burst in the same stack.
- Synced variant: identical duration + ease as the driver, or the chord falls apart.
## See also
`counting-dynamic-scale` (the classic chord driver) · `depth-scatter-assemble` (3D per-element cloud) · `card-morph-anchor` (burst out of a morphed card) · `sine-wave-loop` (post-landing life).