> ## Documentation Index
> Fetch the complete documentation index at: https://hyperframes.heygen.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Typewriter

> Character-by-character text reveal with a deterministic blinking cursor.

export const InstallCommand = ({command}) => {
  const [copied, setCopied] = React.useState(false);
  const copy = async () => {
    try {
      if (navigator.clipboard && window.isSecureContext) {
        await navigator.clipboard.writeText(command);
      } else {
        const previous = document.activeElement;
        const scratch = document.createElement("textarea");
        scratch.value = command;
        scratch.setAttribute("readonly", "");
        scratch.style.position = "fixed";
        scratch.style.opacity = "0";
        document.body.appendChild(scratch);
        scratch.select();
        document.execCommand("copy");
        document.body.removeChild(scratch);
        previous?.focus?.();
      }
      setCopied(true);
      setTimeout(() => setCopied(false), 2000);
    } catch {}
  };
  return <div className="hf-install-command not-prose my-4 flex items-stretch overflow-hidden rounded-xl border border-zinc-200 bg-zinc-50 dark:border-zinc-800 dark:bg-zinc-900">
      <code className="flex-1 overflow-x-auto whitespace-nowrap border-r border-zinc-200 px-4 py-3 font-mono text-sm text-zinc-800 dark:border-zinc-800 dark:text-zinc-100">
        {command}
      </code>
      <button type="button" onClick={copy} data-copied={copied ? "true" : "false"} aria-label={`Copy ${command} to the clipboard`} className="hf-install-copy">
        <svg className="hf-install-copy-clipboard" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 18 18" fill="none" stroke="currentColor" strokeWidth="1.5" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
          <path d="M14.25 5.25H7.25C6.14543 5.25 5.25 6.14543 5.25 7.25V14.25C5.25 15.3546 6.14543 16.25 7.25 16.25H14.25C15.3546 16.25 16.25 15.3546 16.25 14.25V7.25C16.25 6.14543 15.3546 5.25 14.25 5.25Z" />
          <path d="M2.80103 11.998L1.77203 5.07397C1.61003 3.98097 2.36403 2.96397 3.45603 2.80197L10.38 1.77297C11.313 1.63397 12.19 2.16297 12.528 3.00097" />
        </svg>
        <svg className="hf-install-copy-check" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 18 18" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
          <path d="M2.75 9.5L6.5 13.25L15.25 4.5" />
        </svg>
      </button>
      <span className="hf-install-copy-status" role="status" aria-live="polite">
        {copied ? "Copied" : ""}
      </span>
    </div>;
};

<iframe className="w-full aspect-video rounded-xl border-0 bg-zinc-100 dark:bg-zinc-800" title="typewriter preview" loading="lazy" srcDoc={`<!doctype html><html><head><meta charset="utf-8"><style>html,body{margin:0;height:100%;overflow:hidden;background:transparent}hyperframes-player{display:block;width:100%;height:100%}</style><script src="https://cdn.jsdelivr.net/npm/@hyperframes/player@0.7/dist/hyperframes-player.global.js"><\/script></head><body><script>fetch("/public/catalog/components/typewriter.json").then(function(r){return r.json()}).then(function(d){var p=document.createElement("hyperframes-player");p.setAttribute("srcdoc",d.html);p.setAttribute("controls","");p.setAttribute("autoplay","");p.setAttribute("loop","");p.setAttribute("muted","");p.setAttribute("poster","https://static.heygen.ai/hyperframes-oss/docs/images/catalog/components/typewriter.png");document.body.appendChild(p)});<\/script></body></html>`} />

## Install

<InstallCommand command="npx hyperframes add typewriter" />

That writes one file: `compositions/components/typewriter.html`.

## Variables

Every one of these has a default, so the piece works untouched. Set the ones you
want to change on the element:

| Variable | Default                      | Accepts                  | What it does                                                                                       |
| -------- | ---------------------------- | ------------------------ | -------------------------------------------------------------------------------------------------- |
| `text`   | `hyperframes add typewriter` | string                   | Line that types itself out character by character.                                                 |
| `tone`   | `ink`                        | `ink`, `paper`, `accent` | Colour of the text and the caret: ink for light frames, paper for dark ones, accent rides --brand. |
| `caret`  | `line`                       | `line`, `block`, `none`  | Caret shape: a thin rule, a terminal-style block, or no caret at all.                              |

Set them with `data-variable-values` on the element that mounts it. These are the
defaults, so this behaves exactly like the preview above until you change one:

```html wrap theme={null}
<div
  data-composition-id="typewriter"
  data-composition-src="compositions/components/typewriter.html"
  data-variable-values='{"text":"hyperframes add typewriter","tone":"ink","caret":"line"}'
></div>
```

## Source

<Accordion title={`typewriter.html`}>
  ```html theme={null}
  <!--
    Typewriter - remocn typography primitive for HyperFrames.

    Paste the markup, CSS and script into a composition. Drive the timeline
    integration from a paused GSAP timeline so renders remain deterministic.

    Variables. The script reads each one, falls back to the declared default on
    anything missing or unrecognised, and writes the result either into the
    markup or into a custom property the CSS above consumes. The timeline recipe
    below is untouched by them: it keeps driving one type progress and one caret
    opacity, and these decide what is typed, in what colour, and behind which
    caret.

      - text (string, default hyperframes add typewriter): the line that types
        itself out. It is written into the existing span, so the reveal keeps
        running character by character over whatever is set. Anything that is
        not a non-empty string keeps the shipped line.
      - tone (ink | paper | accent, default ink): colour of both the text and
        the caret. ink is near-black for light frames, paper near-white for dark
        ones, accent rides --brand.
      - caret (line | block | none, default line): caret shape. line is the
        shipped 3px rule, block is a 22px slab in the style of a terminal
        cursor, none removes the caret entirely and closes the gap after the
        text.

    On every default the result is identical to the original: a near-black
    monospace line typing itself out behind a 3px caret.
  -->

  <div
    class="hf-remocn-typewriter"
    data-composition-variables='[
      { "id": "text", "type": "string", "role": "content", "label": "Text", "description": "Line that types itself out character by character.", "default": "hyperframes add typewriter" },
      { "id": "tone", "type": "enum", "role": "style", "label": "Tone", "description": "Colour of the text and the caret: ink for light frames, paper for dark ones, accent rides --brand.", "default": "ink", "options": [{ "value": "ink", "label": "Ink" }, { "value": "paper", "label": "Paper" }, { "value": "accent", "label": "Accent" }] },
      { "id": "caret", "type": "enum", "role": "style", "label": "Caret", "description": "Caret shape: a thin rule, a terminal-style block, or no caret at all.", "default": "line", "options": [{ "value": "line", "label": "Line" }, { "value": "block", "label": "Block" }, { "value": "none", "label": "None" }] }
    ]'
  >
    <span>hyperframes add typewriter</span><i></i>
  </div>

  <style>
    .hf-remocn-typewriter {
      color: var(--hf-type-color, #18181b);
      font-family: Inter, system-ui, sans-serif;
      font-weight: 900;
      letter-spacing: -0.04em;
    }
    .hf-remocn-typewriter {
      display: inline-flex;
      align-items: center;
      gap: 4px;
      font:
        800 42px/1 ui-monospace,
        SFMono-Regular,
        Menlo,
        monospace;
    }
    .hf-remocn-typewriter span {
      display: inline-block;
      max-width: calc(var(--hf-type-progress, 1) * 100%);
      overflow: hidden;
      white-space: nowrap;
    }
    .hf-remocn-typewriter i {
      display: var(--hf-caret-display, block);
      width: var(--hf-caret-width, 3px);
      height: 42px;
      border-radius: 999px;
      background: var(--hf-type-color, #18181b);
      opacity: var(--hf-caret-opacity, 1);
    }
  </style>

  <script>
    (function () {
      "use strict";

      var vars =
        window.__hyperframes && window.__hyperframes.getVariables
          ? window.__hyperframes.getVariables()
          : {};

      // Unrecognised overrides return to their declared defaults.
      var tones = {
        ink: "#18181b",
        paper: "#fafafa",
        accent: "var(--brand, #34d399)",
      };
      var carets = {
        line: { width: "3px", display: "block" },
        block: { width: "22px", display: "block" },
        none: { width: "3px", display: "none" },
      };

      function pick(table, value, fallback) {
        return Object.prototype.hasOwnProperty.call(table, value) ? value : fallback;
      }

      var tone = tones[pick(tones, vars.tone, "ink")];
      var caret = carets[pick(carets, vars.caret, "line")];
      var text = typeof vars.text === "string" && vars.text !== "" ? vars.text : null;

      var roots = document.querySelectorAll(".hf-remocn-typewriter");
      for (var i = 0; i < roots.length; i += 1) {
        var root = roots[i];
        root.style.setProperty("--hf-type-color", tone);
        root.style.setProperty("--hf-caret-width", caret.width);
        root.style.setProperty("--hf-caret-display", caret.display);

        var line = root.querySelector("span");
        if (text !== null && line) {
          line.textContent = text;
        }
      }
    })();
  </script>

  <!--
    Timeline integration:
    tl.fromTo('.hf-remocn-typewriter', { '--hf-type-progress': 0 }, { '--hf-type-progress': 1, duration: 1.2, ease: 'steps(28)' }, startTime); tl.to('.hf-remocn-typewriter i', { '--hf-caret-opacity': 0.2, duration: 0.24, repeat: 7, yoyo: true, ease: 'none' }, startTime + 0.2);
  -->
  ```
</Accordion>

## Usage

Open `compositions/components/typewriter.html` and paste its contents into your composition. See the comment header in the file for detailed instructions.

Tagged `video-primitive` `motion-primitive` `remocn-port` `typography`.

## Related topics

* [Browse the complete Catalog](/catalog)
* [Add assets and Catalog items in Studio](/studio/assets-and-blocks)
* [Build a richer composition](/go-further)


## Related topics

- [Comment Cards](/catalog/blocks/yt-comment-card.md)
- [Vocabulary that changes output](/prompting/vocabulary.md)
- [Caption styles](/prompting/captions-catalog.md)
