Fonts and licensing

Fonts and licensing

Generated from docs/fonts.md in the repository. Edit it there; changes made on the wiki are overwritten.

A design draws text with fonts you give it: Readmint has no system fonts and never fetches one. This page is the short version; the exact rules are in design-format.md and renderer.md.

Adding a font

A font is an asset of the design: family, src (a relative path next to the design file, or a base64 data URI), optionally weight and style, and a licence you declare. TrueType, OpenType (CFF), WOFF and WOFF2 are read. The bundled starter templates use Montserrat, the profile templates Archivo, Noto Sans, Noto Sans Mono, Geist and Geist Mono, all under the SIL Open Font License 1.1; see components.md for replacing them with your own font and for fallback fonts that cover more scripts.

{
  "id": "body",
  "family": "My Font",
  "src": "fonts/MyFont-Regular.ttf",
  "licence": { "embedding": "allowed", "name": "OFL-1.1" }
}

When a font is embedded

By default the SVG carries a subset of the font: only the glyphs the design draws. That keeps the output self-contained, which GitHub needs, since it loads no external font. The renderer embeds a font only when all of this holds:

• the asset declares licence.embedding: "allowed";
• the font file's own embedding permission (OS/2 fsType) allows it; the stricter of the two wins;
• the font has no Reserved Font Name (SIL Open Font License). An embedded subset is a Modified Version, which may not use that name.

Otherwise the text is drawn as path data and nothing of the font is embedded; the render warns font-not-embeddable or font-reserved-name. Set drawAs: "paths" on a font to always draw its text as paths.

Script coverage of the bundled templates

A character the font has no glyph for is looked up in the font's fallback fonts, in order; if none has it, it is not drawn, takes no space, and the render warns missing-glyph naming the code points.

template	text	covered	not drawn
starter templates	Montserrat (no fallback)	Latin, Latin Extended-A, Vietnamese, Cyrillic (U+0400..04FF)	Greek except Δ, Ω, μ, π; emoji, CJK, other scripts
year-ring, horizon	Archivo, with Noto Sans as its fallback	Latin, Latin Extended-A, Vietnamese from Archivo; Cyrillic and Greek from Noto Sans (Δ, Ω, μ, π from Archivo)	emoji, CJK, other scripts
horizon code and label text	Geist Mono, with Noto Sans Mono as its fallback	Latin, most of Latin Extended-A, Vietnamese, Cyrillic of the Slavic languages from Geist Mono; the rest of Latin Extended-A, Cyrillic and Greek from Noto Sans Mono (Λ, Ω, λ, μ, π from Geist Mono)	emoji, CJK, other scripts
pinscreen	Geist and Geist Mono, with Noto Sans and Noto Sans Mono as their fallbacks	Latin, most of Latin Extended-A, Vietnamese, Cyrillic of the Slavic languages from Geist and Geist Mono (Geist also has IJ ij and ω); the rest of Latin Extended-A, Cyrillic and Greek from Noto Sans and Noto Sans Mono	emoji, CJK, other scripts

The remedy for a script a template does not cover is a font asset that has it, listed in the fallback of the design's fonts (a font that may be embedded and a licence you can declare), placed next to the design file:

{
  "id": "han",
  "family": "My CJK Font",
  "src": "fonts/MyCJK-Regular.ttf",
  "licence": { "embedding": "allowed", "name": "OFL-1.1" }
}

and "fallback": ["han"] on each font asset that draws the text. A fallback adds to the output only the glyphs actually drawn from it.

Your responsibility

The licence is what you declare; Readmint cannot read a licence text. Declare restricted for a font you may not redistribute, and keep font files you may not redistribute out of public repositories. Fonts committed to the Readmint repository are only ones that may be redistributed, and their licence is recorded beside them.

Raster output

PNG, WebP, APNG and GIF are drawn from the fonts the SVG embeds, so a font of any supported type works. A font the renderer drew as paths needs nothing more; text with no usable font fails the export with raster-font rather than writing blank text. See raster.md.