Scatcode

Scatcode is an experimental character encoding that can support any characters. It supports non-Unicode characters like Sitelen Pona, Tengwar and Liparxe. You can even add your own characters!

See scatcode.gimite.net for an overview and demo.

Table of Contents

• Encoding Format
• Domain Configuration (/scatcode.json)
• Libraries
  • scatcode-core
  • scatcode-text
  • scatcode-text-area
• License

Encoding Format

Scatcode is an extension of Unicode. It abuses a deprecated Unicode feature called language tag, but puts a domain name instead of a language code in the tag. The encoding format is:

U+E0001 [domain-encoded] U+E007F [text]

Components

1. Domain Tag Start: U+E0001 signals the beginning of a domain specification
2. Domain Characters: Each ASCII character in the domain name is encoded by adding 0xE0000 to its codepoint
   • For example: example.com becomes U+E0065 U+E0078 U+E0061 U+E006D U+E0070 U+E006C U+E0065 U+E002E U+E0063 U+E006F U+E006D
   • An empty domain name indicates the default (Unicode) domain
3. Domain Tag End: U+E007F signals the end of domain specification and the start of the actual text
4. Text Content: The actual text using codepoints defined in the domain
   • This often uses codepoints in Unicode Private Use Area, but can be any Unicode codepoints

Example Encoding

The text "toki pona" written in Sitelen Pona is encoded into:

1. U+E0001: LANGUAGE TAG
2. "sitelenpona.gimite.net" encoded using tag characters (by adding 0xE0000)
3. U+E007F: CANCEL TAG
4. U+F196C: Unicode Private Use Area codepoint for SITELEN PONA IDEOGRAPH TOKI
5. U+F1954: Unicode Private Use Area codepoint for SITELEN PONA IDEOGRAPH PONA

You can also select text in the text area in scatcode.gimite.net and look at the table below to see how it is encoded.

Domain Configuration (/scatcode.json)

A "domain" of a character set in Scatcode is defined in https://domain/scatcode.json.

See https://sitelenpona.gimite.net/scatcode.json as an example.

Most importantly, /scatcode.json provides a web font in its fallbackFont property. It can be used to render characters in the domain.

/scatcode.json also provides a list of characters in the domain in its characters property.

/scatcode.json must have a CORS policy to allow access from any domains.

Libraries

scatcode-core

Core library for Scatcode text encoding and parsing. It also provides a web component for displaying Scatcode text.

Usage:

This embeds "toki pona" written in Sitelen Pona in HTML:

<script type="module" src="https://scatcode.gimite.net/scatcode-core-0.1.0.es.js"></script>
<scatcode-text>&#xE0001;&#xE0073;&#xE0069;&#xE0074;&#xE0065;&#xE006C;&#xE0065;&#xE006E;&#xE0070;&#xE006F;&#xE006E;&#xE0061;&#xE002E;&#xE0067;&#xE0069;&#xE006D;&#xE0069;&#xE0074;&#xE0065;&#xE002E;&#xE006E;&#xE0065;&#xE0074;&#xE007F;&#xF196C;&#xF1954;&#xE0001;&#xE007F;</scatcode-text>

scatcode-text

React component for rendering Scatcode-encoded text.

Installation:

npm install scatcode-text

Usage:

This renders "toki pona" written in Sitelen Pona:

import { ScatcodeText } from 'scatcode-text';

function App() {
  return (
    <ScatcodeText>
      &#xE0001;&#xE0073;&#xE0069;&#xE0074;&#xE0065;&#xE006C;&#xE0065;&#xE006E;&#xE0070;&#xE006F;&#xE006E;&#xE0061;&#xE002E;&#xE0067;&#xE0069;&#xE006D;&#xE0069;&#xE0074;&#xE0065;&#xE002E;&#xE006E;&#xE0065;&#xE0074;&#xE007F;&#xF196C;&#xF1954;&#xE0001;&#xE007F;
    </ScatcodeText>
  );
}

scatcode-text-area

React component providing an editable text area for Scatcode-encoded text.

Installation:

npm install scatcode-text-area

Usage:

This shows an editable text area that supports Scatcode-encoded text:

import { ScatcodeTextArea } from 'scatcode-text-area';

function Editor() {
  const [content, setContent] = React.useState('');
  return (
    <ScatcodeTextArea
      value={content}
      onChange={(value) => setContent(value)}
    />
  );
}

License

• Spec of the encoding format and domain configuration: Public domain
• scatcode-core and scatcode-text libraries: MIT
• scatcode-text-area library and scatcode-demo app: GPL