Rustmix X4 Firmware v1.1.0 — Hindi and Gujarati EPUB Support

Rustmix X4 Firmware v1.1.0

This release adds host-prepared Indic EPUB rendering for Hindi, Sanskrit, and Gujarati books on the Xteink X4.

Highlights

• Adds Devanagari EPUB rendering for Hindi and Sanskrit content.
• Adds Gujarati EPUB rendering, including mixed-script books.
• Performs complex Indic shaping on a computer so the constrained X4 firmware does not need to run a large shaping engine on-device.
• Uses page-local FAT 8.3-safe cache assets under /FCACHE/<BOOKID>.
• Splits dense shaped pages before firmware-safe glyph, VRUN-byte, or page-font limits are exceeded.
• Cleans macOS AppleDouble ._* files and .DS_Store metadata before cache validation.
• Preserves existing Reader features, TXT/EPUB browsing, bookmarks, settings, Wi-Fi Transfer, and the accepted X4/CrossPoint-compatible partition layout.

Validated books

• Garud Purana EPUB with Hindi and Sanskrit Devanagari text.
• Srimad Bhagavat Mahapuran Volume 1 EPUB with Hindi Devanagari text.
• Gujarati Valmiki Ramayana EPUB.

Preparing an Indic EPUB cache

Use static Noto TTF files and place the generated cache at the SD-card root:

python3 tools/font_prepare/prepare_book.py epub \
  --book "/path/to/book.epub" \
  --device-path GARUDPUR.EPU \
  --latin-font "/path/to/NotoSans-Regular.ttf" \
  --devanagari-font "/path/to/NotoSansDevanagari-Medium.ttf" \
  --out "/Volumes/<SDCARD>/FCACHE" \
  --clean

Add --gujarati-font "/path/to/NotoSansGujarati-Regular.ttf" for Gujarati books.

See README.md, USERGUIDE.md, and SCREENSHOTS.md for the complete workflow and physically validated device screenshots.