wip-reference/site/public/fonts/README.md

# Self-hosted fonts

These are unmodified binaries from official upstream sources. Only the faces
used by the site are retained: Lyth Mono regular/bold, EB Garamond regular/bold
and their italics, plus each family's regular TTF for build-time outline
extraction with `opentype.js`. Browsers use WOFF2, not the TTFs. No Nerd, Term,
Square, Round, variable, light, or medium faces are included.

## Lyth Mono

- Repository: <https://github.com/why-trv/LythMono>
- Selected non-prerelease release: **v0.10.0**, published 2026-02-06.
- Pinned tag commit: `71d1cf4f325663705ab41ee1908427ea435b2e5d`.
- Pinned Iosevka source submodule: `a90e82cf6f37cc9b82e47151024c86cfe0693874`.
- Official release archive:
  <https://github.com/why-trv/LythMono/releases/download/v0.10.0/LythMono.zip>
- Archive SHA-256, checked against the GitHub release asset digest:
  `06b8c05671572e8cba61bf494404d3b973df348c607cd33f3153a374247d6607`.
- Extracted only `LythMono/WOFF2/LythMono-Regular.woff2`,
  `LythMono/WOFF2/LythMono-Bold.woff2`, and
  `LythMono/TTF/LythMono-Regular.ttf` (hinted versions). The archive is not
  retained.
- License: `LythMono-LICENSE.md`, copied from `LICENSE.md` at the pinned commit;
  SIL Open Font License 1.1, including upstream copyright notices.
- Internal family: **Lyth Mono**. Regular full name: **Lyth Mono**;
  PostScript name: **Lyth-Mono**. Bold PostScript name: **Lyth-Mono-Bold**.
  Regular TTF version: `Version 0.10.0; ttfautohint (v1.8.4)`.

Regular TTF metrics (font units): units/em 1000; hhea ascender 925, descender
-195, line gap 50; OS/2 typo ascender 925, descender -245, line gap 0;
Windows ascent/descent 925/245; cap height 720; x-height 540. ASCII `0`, `W`,
`i`, `p`, and the four box glyphs below all advance **604** units (0.604em;
8.456px at 14px). This is not a 0.6em font. Glyph count: 12174.

| Character | Unicode | Glyph ID | Ink bounds `(xMin, yMin, xMax, yMax)` |
| --- | --- | --- | --- |
| │ | U+2502 | 7535 | (264, -245, 340, 925) |
| ├ | U+251C | 7561 | (264, -245, 604, 925) |
| └ | U+2514 | 7553 | (264, 306, 604, 925) |
| ─ | U+2500 | 7533 | (0, 306, 604, 374) |

These are real, nonempty outlines verified with `opentype.js`, not fallback
characters. The horizontal stroke's center is y=340, and vertical strokes
reach the font's 925/-245 line extents. Explicit line-height and vertical
alignment matter when joining animated strokes to text.

## EB Garamond

- Official source: <https://github.com/octaviopardo/EBGaramond12>
- Pinned commit: `106a4a6d377987459ae5e68673a4570f13b957fb`.
- This is the upstream revision recorded by Google Fonts in
  `ofl/ebgaramond/METADATA.pb` at distribution commit
  `f8c1d3d6cc75e30d77130bdcbfbff27e3b6233fe`.
- No published GitHub release is available at the source repository. Files
  were downloaded directly from that pinned source commit, not a third-party
  font CDN: `https://raw.githubusercontent.com/octaviopardo/EBGaramond12/106a4a6d377987459ae5e68673a4570f13b957fb/`.
- Source paths: `fonts/webfonts/EBGaramond-{Regular,Bold,Italic,BoldItalic}.woff2`
  and `fonts/ttf/EBGaramond-Regular.ttf`.
- License: `EBGaramond-OFL.txt`, copied from `OFL.txt` at the pinned commit;
  SIL Open Font License 1.1, including upstream copyright notices.
- Internal family: **EB Garamond**. Regular full name: **EB Garamond Regular**;
  PostScript name: **EBGaramond-Regular**. Other included PostScript names:
  **EBGaramond-Bold**, **EBGaramond-Italic**, **EBGaramond-BoldItalic**.
- The static regular TTF reports `Version 1.002; ttfautohint
  (v1.8.4.16-eb64)`. Google Fonts' newer variable version is not included;
  the static faces above are deliberately used as shipped by upstream.

Regular TTF metrics (font units): units/em 1000; hhea and OS/2 typo ascender
1007, descender -298, line gap 0; Windows ascent/descent 1047/390; cap height
650; x-height 400. Advances: `0` 480, `W` 916, `i` 245, `p` 519. Glyph count:
3247. It does not contain the four box-drawing characters above.

## Japanese / CJK fallback

Neither regular TTF maps any codepoints in Hiragana (U+3040–309F), Katakana
(U+30A0–30FF), CJK Unified Ideographs (U+4E00–9FFF), or Extension A
(U+3400–4DBF). `あ`, `ア`, `漢`, `日`, and `本` all map to glyph 0 in both.
Do not use their `.notdef` outlines for Japanese glyph extraction.

The proportional CSS stack uses installed `Noto Serif JP`, `Hiragino Mincho
ProN`, `Yu Mincho` / `YuMincho`, then generic `serif`. The mono stack retains
system monospace choices and installed `Noto Sans Mono CJK JP`. These are
fallback names only: no additional CJK font is downloaded or requested from
an external provider. Japanese metrics depend on the user's installed font.

## Build-time outlines

`src/lib/landing-glyphs.mjs` uses `opentype.js@2.0.0` during Astro rendering.
It reads `public/fonts/LythMono-Regular.ttf` from the site working directory,
extracts box glyphs directly through cmap (no programming ligatures or GSUB
shaping), and normalizes the vertical cell to the 24px tree row. Direct glyph
lookup also avoids Lyth Mono's contextual GSUB lookups that OpenType.js 2.0.0
does not support. The 0.604em advance and connection centers are retained;
tree stroke edges are expanded symmetrically by 25% for legibility (the resting
vertical stem is 1.33px). Cell boundaries stay fixed so neighboring glyphs join.
The distributed font binaries and ordinary text weights are unchanged.

The resulting SVG paths are emitted into static HTML; neither the parser nor
the TTF is fetched by the browser. Anime.js controls the shared tree transform
and reveals the persistent trunk through a mask; there is no switch back to
HTML box-drawing text on completion. Labels and normal content remain text.

## Integrity

`SHA256SUMS` records every font and upstream license in this directory. Verify
from this directory with `sha256sum --check SHA256SUMS`. Individual hashes
pin the exact binaries even if upstream tags or release assets change.