Font Range

Google Font provides a subset of Korean, Japanese, and Chinese Slicing Patterns through machine learning.

Font Range helps you to subset using unicode range in Google Fonts.

Usage

Requires

It has dependencies on the following packages:

pip3 install fonttools[ufo,woff,unicode] zopfli brotli

Basics

This project has three types.

• fontRange(): Subset based on unicode-range in the CSS file.
• fontSubset(): Subset based on text or text file.
• fontPipe(): Use fontRange() and fontSubset() to perform multiple subset operations.

// fontRange
fontRange(font_path, css_url_or_path);
fontRange(font_path, css_url_or_path, save_dir);       // Option1
fontRange(font_path, css_url_or_path, { ...options }); // Option2

// fontSubset
fontRange(font_path);
fontRange(font_path, save_dir);       // Option1
fontRange(font_path, { ...options }); // Option2

// fontPipe
fontPipe([
  { font_path },                                      // As `fontSubset(font_path)`
  { font_path, option: { text: "abc" } },             // As `fontSubset(font_path, { text: "abc" })`
  { font_path, option: { textFile: file_path } },     // As `fontSubset(font_path, { textFile: file_path })`
  { font_path, option: { cssFile: css_url_or_path } } // As `fontRange(font_path, css_url_or_path)`
]);
fontPipe([{ font_path1 }, { font_path2 }], "<index>/<total>"); // Sharding option use like `1/2`

CSS URL?

The URL of Noto Sans is included in the package.

const targets = {
  weston:   "https://fonts.googleapis.com/css2?family=Noto+Sans&display=swap",
  korean:   "https://fonts.googleapis.com/css2?family=Noto+Sans+KR&display=swap",
  japanese: "https://fonts.googleapis.com/css2?family=Noto+Sans+JP&display=swap",
  chinese:  "https://fonts.googleapis.com/css2?family=Noto+Sans+SC&display=swap",
  chinese_traditional: "https://fonts.googleapis.com/css2?family=Noto+Sans+TC&display=swap",
};

Default Options

List of options available for all function options.

type Format = "otf" | "ttf" | "woff2" | "woff" | "woff-zopfli";
interface FontDefaultOptionI {
  saveDir:     string;   // Directory to save the generated subset or downloaded CSS
  format:      Format;   // Subset type to create
  nameFormat:  string;   // File name format to create
  logFormat:   string;   // Log format to print
  defaultArgs: string[]; // `pyftsubset` option - default
  etcArgs:     string[]; // `pyftsubset` option - for users
}

• save_dir's default: <font_path>
• format's default: "woff2"
• nameFormat's default: "{NAME}_{INDEX}{EXT}"
• defaultArgs's default:

[
  "--layout-features=*",
  "--glyph-names",
  "--symbol-cmap",
  "--legacy-cmap",
  "--notdef-glyph",
  "--notdef-outline",
  "--recommended-glyphs",
  "--name-legacy",
  "--drop-tables=",
  "--name-IDs=*",
  "--name-languages=*"
]

• etcArgs's default: []

Font Range

It is designed to be able to do a subset using unicode-range of CSS.

Option

The name of the generated file can be determined from the CSS.

interface FontRangeOptionI extends FontDefaultOptionI {
  fromCSS: "default" | "srcIndex" | "srcName";
}

• default: The index of the file name increases in the generated order
• srcIndex: The index of the file name uses src in CSS #9
  • Based on the first url()
• srcName: The file name uses src in CSS
  • Based on the first url()

Font Subset

It is designed to be able to do a general subset.

Option

By default, all letters are included, but you can set the letters to include:

interface FontSubsetOptionI extends FontDefaultOptionI {
  textFile: string; // From text file
  text:     string; // Letter like `abc`
}

Font Pipe

It offers a simple API when doing a large amount of subsets.

Performance is optimized using worker pool and provides sharding for distributed environments.

Option

If cssFile has attributes, it is recognized as fontRange().

interface FontPipeOptionI extends FontRangeOptionI, FontSubsetOptionI {
  cssFile: string;
}

Sharding

You can control sharing using argument or environment variable.
If both values are used together, argument is applied first.

• Argument: Explicitly used through function.

fontPipe([{ font_path1 }, { font_path2 }], "<index>/<total>");

• Environment Variable: Make it easy to use in CI, npm scripts, ..etc.

SHARD="<index>/<total>"
node subset.js

License

Licensed under the MIT. See the LICENSE file for details.