scrmbl

Dependency-free scramble/decode text animation. Characters cycle through random glyphs and resolve into your text.

pnpm add scrmbl

Quick start

React — scrmbl/react

import { Scramble, useScramble } from "scrmbl/react";

// Component: scrambles in on mount, re-scrambles when the text changes.
<Scramble charset="upper" order="random">{title}</Scramble>;

// Hook: attach to any element, trigger whenever you like.
function NavLink({ children }: { children: string }) {
  const { ref, replay } = useScramble<HTMLAnchorElement>({ duration: 450 });
  return <a ref={ref} onMouseEnter={replay}>{children}</a>;
}

Vanilla / TypeScript — scrmbl

import { scramble, ScrambleController } from "scrmbl";

// One-liner: scrambles the element's existing text in.
const ctrl = scramble(document.querySelector("h1")!, { charset: "symbols" });

// Animate to new text; interrupting mid-animation is handled gracefully.
ctrl.update("New headline");
ctrl.replay();  // re-run from nothing
ctrl.finish();  // jump to the end
ctrl.destroy(); // release the element

Vue — scrmbl/vue

<script setup lang="ts">
import { Scramble } from "scrmbl/vue";
</script>

<template>
  <Scramble :text="title" charset="upper" order="random" @complete="onDone" />
</template>

Svelte — scrmbl/svelte

<script lang="ts">
  import { Scramble } from "scrmbl/svelte";
  let { title } = $props();
</script>

<Scramble text={title} charset="upper" order="random" />

Svelte ships as source (.svelte), compiled by your bundler — Svelte 5+.

Options

Every entrypoint accepts the same options (as props in React/Vue/Svelte, as an options object in vanilla).

| Option | Default | Description | | --- | --- | --- | | duration | 800 | Total animation time in ms. Always honored — stagger compresses for long text, so a 40-character headline and a 400-character paragraph both finish on time. | | stagger | 20 | Delay in ms between successive characters beginning to resolve. | | order | "start" | Resolve pattern: "start", "end", "center", "edges", "random". | | charset | "alnum" | Glyph pool: a preset name or any custom string of characters. | | glyphRate | 30 | Glyph swaps per second while a character is scrambling. | | ignore | "" | Characters never scrambled (whitespace never is, regardless). | | scrambleAll | true | Set false to only animate characters that changed between updates — great for live values like prices and counters. | | sweep | false | Wave mode: each character keeps its old glyph until its turn, producing a sweep. Default is the classic everything-scrambles-then-resolves decode. | | seed | random | Deterministic runs: the same seed + text + options produce identical frames. | | respectReducedMotion | true | Snap instantly to the final text when the user prefers reduced motion. | | onStart / onComplete | — | Lifecycle callbacks (events start/complete in Vue, onstart/oncomplete props in Svelte). |

Charset presets

upper · lower · digits · alnum · hex · binary · symbols · blocks (░▒▓█…) · braille (⠿⡿⣷…) · katakana

import { CHARSETS } from "scrmbl";

Any string works too: charset: "01│─┌┐".

Styling

While animating, the library sets data attributes you can hook with CSS:

/* the element */
[data-scrmbl-active] { /* animation in flight */ }

/* per-character spans; [data-glyph] = currently showing a random glyph */
[data-scrmbl-cell][data-glyph] {
  color: var(--accent);
  opacity: 0.55;
}

After the animation settles, the element flattens back to plain text — copy/paste, SEO, and line wrapping behave exactly as if scrmbl was never there.

Accessibility

• The element's aria-label always carries the real text; per-character spans are aria-hidden, so screen readers never hear glyph soup.
• prefers-reduced-motion: reduce skips the animation entirely (disable via respectReducedMotion: false if you must).

SSR

Server rendering outputs the final text — no hydration mismatch, no flash of empty content. The scramble-in runs client-side on mount (autoStart={false} opts out in the component adapters).

Notes

• Fonts: with proportional fonts, widths jitter slightly while glyphs cycle. Monospace fonts, font-variant-numeric: tabular-nums (for digits), or width-stable charsets (blocks, braille) give the steadiest look.
• Graphemes: text is segmented with Intl.Segmenter where available, so emoji (including ZWJ sequences) scramble as single units.
• Engine: each frame is a pure function of time — frameAt(plan, t) — which is what makes seeded runs perfectly reproducible. The pure pieces (computePlan, frameAt, segment, CHARSETS) are exported if you want to build your own renderer.

License

MIT © Travis McCormick