Basic LuaTeX OpenType Manager
In his terse documentation for PiTeX, Paul Isambert lists, among the "mandatory PiTeX" files, the following:
| file name | Description |
|---|---|
| fonts.ptx | Interface for fonts; relies on the next file. |
| fonts.ptxlua | The Lua fontloader; should become independant some day. |
| foundry-settings.lua | Default settings for the fontloader. |
Well: the day has come, and the fontloader has now become blopentype: a Basic LuaTeX OpenType Manager.
The basic code is copied almost verbatim from Isambert's PiTeX, save the adoption of the canonical filename extensions tex for LuaTeX macros, lua for LuaTeX scripts, and blot-sets.lua for the basic basic settings.
The required dependencies are Isambert packages texapi, YaX and Gates, as stated in DEPENDS.txt.
You may find an example of usage in the blottest.[tex|pdf] files, and some basic documentation in blopentype.md.
On LuaTeX <0.17 a security hole allowed the package to write on $TEXMFLOCAL without explicit permissions, so the program actually worked almost by accident. Now that the hole has been plugged, the package must be run with the --shell-escape flag enabled, otherwise it will not write the required, global readable.txt database file, or the individual *.lua font metrics files for each font. This procedure is only required to generate or update the database or to add new font family metrics on the system; once these files are in the blotfonts directory in $TEXMFLOCAL the flag is no longer required.
This update on the LuaTeX engine now requires a font database generating/updating script, which is top in the to do list now. Meanwhile, the workaround described above should work.
The macros are still barely documented, and massively keep the names of their parent (PiTeX) package; that may be fixed some day.
The font database is stored at $TEXMFLOCAL/texmf/luatex/blotfonts/readable.txt.
It is updated automatically after installing and using new fonts, but you may edit it, or else delete/rename(backup) the database by hand, and rerun LuaTeX to rebuild it.
The character table for each typeface is stored in the luatex/blotfonts directory as a flat lua file; it would be nice to have it compiled as a luac/luc file to save some space, some day.
Good luck, and happy LuaTeXing
(C) 2022-2023 Paul Isambert (author) and Luis Rivera (maintainer).
LaTeX Project Public License, LPPL Version 1.3c 2008-05-04 or MIT License