Typewriter

A greeting struck on a manual typewriter.

isomer.sh/effects/typewriter

Knobs

Continue on iPhone
Preset
#202B3B
#F2EBDD
0.48
4.50
Light1
0.45
Shape2
1.00
0.65
Motion2
0.55
0.70
Texture3
0.60
0.55
0.30
Still frame

What reduced motion shows: 4 s.

Install

Code

components/isomer/typewriter.tsx
'use client';
// Generated by isomer. Do not edit by hand; run `isomer add` again to update. (from packages/react/src/Typewriter.tsx)
// generated by packages/react/scripts/gen-components.mjs, do not edit
import type { CSSProperties } from 'react';
import { useIsomerCanvas, usePrefersReducedMotion, type Mount, type ImageInput, type ImageSource } from './useIsomerCanvas';
import { useLive, usePointer, type LiveSpec } from './live';
// @ts-ignore: the runtime is plain JS with no type declarations
import * as runtime from './typewriter.js';
// @ts-ignore: the baked atlas as a PNG data URL
import atlas from './typewriter.image.js';

const { DEFAULTS, mount, loadImage } = runtime as { DEFAULTS: TypewriterKnobs; mount: Mount; loadImage: (url: string) => Promise<ImageSource> };

export interface TypewriterKnobs {
  ink: string;
  paper: string;
  sizeScale: number;
  jitter: number;
  wear: number;
  speed: number;
  rhythm: number;
  unevenness: number;
  paperGrain: number;
  impression: number;
  strike: number;
  smudge: number;
}

export interface TypewriterProps extends Partial<TypewriterKnobs> {
  className?: string;
  style?: CSSProperties;
  /** Render this one frame (seconds) and run no clock. Used by the parity tests. */
  time?: number;
  paused?: boolean;
  /** The clock stops at t = 7 and holds that frame. Draw t = 4 once when the user prefers reduced motion. Default true. */
  respectReducedMotion?: boolean;
  /** Keep each frame readable after it is shown, for canvas.toDataURL or readPixels. Read at mount. Default false. */
  preserveDrawingBuffer?: boolean;
  /** The image the shader reads. Default: the baked glyph atlas of "Dear June,". */
  image?: ImageInput;
  /**
   * Live inputs, when there is no `time` and the user does not prefer reduced motion: A press on the canvas
   * restarts the effect. Default true.
   */
  live?: boolean;
}

/** Where each live input comes from: the spec's `live` block. */
const LIVE: LiveSpec<TypewriterKnobs> = {
  inputs: [],
  follow: { stiffness: 1200.0, dampingRatio: 1.0 },
  event: { trigger: 'press' },
  settleAt: 7.0,
};

export const typewriterDefaults: Readonly<TypewriterKnobs> = DEFAULTS;

export function Typewriter({ className, style, time, paused, respectReducedMotion, preserveDrawingBuffer, image, live, ...props }: TypewriterProps) {
  const knobs = { ...DEFAULTS };
  for (const k of Object.keys(DEFAULTS) as (keyof TypewriterKnobs)[]) {
    const v = props[k];
    if (v !== undefined) (knobs as Record<string, unknown>)[k] = v;
  }
  // A fixed time is test mode, and reduced motion draws the poster: either way the live inputs stay off (no
  // sensors, no pointer, no events) and the knobs render as given.
  const reduced = usePrefersReducedMotion() && respectReducedMotion !== false;
  const inputs = useLive(LIVE, mount, knobs, time === undefined && live !== false && !reduced);
  const ref = useIsomerCanvas({ mount: inputs.mount, knobs, time, paused, respectReducedMotion, preserveDrawingBuffer, posterTime: 4.0, settleAt: inputs.enabled ? undefined : 7.0, image: image ?? atlas, loadImage });
  usePointer(ref, inputs);
  return <canvas ref={ref} className={className} style={{ display: 'block', width: '100%', height: '100%', ...style }} />;
}

Parity

iPhone 17 Pro simulator, iOS 26.3.1 against Chromium headless + SwiftShader, 15 October 2026.