## Summary
This PR adds the [Libre Baskerville
](https://github.com/impallari/Libre-Baskerville) font family to the
fonts available for download in CrossPoint.
## Additional Context
Baskerville is a classic font family, widely available in some form or
the other in most ereaders and widely used in publishing and in the
academy.
Libre Baskerville is a libre (SIL Open Font License v1) implementation
of it, which makes it possible for CrossPoint to ship it without issues.

---
### AI Usage
Did you use AI tools to help write this code? _**NO**_
## Summary
**What is the goal of this PR?**
* Provide a better default weight of Bitter font for improved rendering
**What changes are included?**
* Changes the default weight for Bitter font that is defined in the
custom font catalog to medium (500) from regular (400) for improved
rendering on e-ink, especially when font anti-aliasing is turned on
## Additional Context
* Bitter font at regular weight can become washed out when AA is on due
to some of the thinner stems and posts of the font. Bumping the weight
up to medium makes it sturdier and holds up better when AA is turned on.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**< NO >**_
Add a complete SD card font subsystem that enables users to install and
use custom fonts beyond the three built-in families. This combines the
back-end firmware support (#1327) with the font configuration, build
pipeline, CI distribution, and user-facing management UI (#1392).
Core font system:
- Custom .cpfont binary format (v4) with multi-style support (regular,
bold, italic, bold-italic) packed into a single file per size
- On-demand glyph loading from SD card with two-pass prewarm rendering
to bulk-read glyphs per page, achieving near-flash performance for
Latin text (~697ms vs ~681ms) and viable CJK rendering (~32% slower)
- Persistent advance cache for layout measurement without SD I/O
- Overflow ring buffer for glyph cache misses during rendering
- Memory-conscious design: only advance tables kept in RAM; glyph
bitmaps, kern tables, and ligatures loaded on demand from SD
Font management:
- On-device WiFi download from GitHub Releases with manifest-based
discovery, install/update detection, and progress UI
- Web interface font upload, listing, and deletion via /fonts page
- Manual SD card copy to /fonts/ or /.fonts/ directories
- Font selection integrated into Settings > Reader > Font Family
Build pipeline:
- Declarative YAML config (sd-fonts.yaml) as single source of truth
for the 17-family font library (serif, sans, mono, accessibility)
- Python converter (fontconvert_sdcard.py) for TTF/OTF to .cpfont with
FreeType rasterization, class-based kerning, and ligature extraction
- Parallel build orchestrator with variable font instance extraction
- CI workflow publishing versioned + stable releases to a dedicated
crosspoint-fonts repository with auto-incrementing revision tags
- Centralized version constants (cpfont_version.py) shared across
build tooling and CI, with firmware headers as manual sync points
Additional fixes:
- CJK characters no longer get hyphens inserted at line breaks
- Advance table eliminates 30+ second stalls during CJK section
indexing for paragraphs with >512 unique codepoints
Closes#930
Co-authored-by: Zach Nelson <zach@zdnelson.com>
Co-authored-by: Justin <itsthisjustin@users.noreply.github.com>
Co-authored-by: jpirnay <jens@pirnay.com>
Co-authored-by: mcrosson <kemonine@kemonine.info>