@Sigfrid On Tue, 30 Sep 2025 19:29:55 +0200 Sigfrid Lundberg <[email protected]> wrote:
> I've also found some problems when it comes to characters used in logic, > and I do need help on how to implement those. They are > > U+22A2 ⊢ syntactic consequence AKA turnstile > U+22A8 ⊨ semantic consequence AKA double turnstile > > Any pointers as to how to add odd niche characters to what is used by eqn? > Based on a brief [excursion] with Linux Debian, if the glyph in question isn't in the compilation of `man groff_char`, you have to substitute groff's default symbol font by an other. [Fontforge] is one of the programs one could use to scan if slots `U+22A2` and `U+22A8` are used -- these strings, label like, appear below the corresponding "boxes" in the synopsis. Because you seek glyphs relevant to math, the [LaTeX font catalogue] could be of help both for coverage, access, and license. The [font selection] for running text, and a second one for math is a recurrent question in TeX's ecosystem. Once identified, you need to connect groff with the non-default fonts to be used. It helps _a lot_ to use the script based approach by [Peter Schaffter]; its action was documented for instance by Garvin Freeborn on [youtube] with Donald Knuth's distinctive `computer modern`. Compared to groff, the rendering of math equations by default [neatroff] can be more appealing; your mileage to install and tinker may vary here. Garvin documented this on one/two videos, too. Best regards, Norwid [excursion]: <https://github.com/nbehrnd/bader_article> [Fontforge]: <https://fontforge.org/> [LaTeX font catalogue]: <https://tug.org/FontCatalogue/mathfonts.html> [font selection]: <https://tex.stackexchange.com/questions/59702/suggest-a-nice-font-family-for-my-basic-latex-template-text-and-math> [Peter Schaffter]: <https://www.schaffter.ca/mom/momdoc/appendices.html#fonts> [youtube]: "Installing Fonts in Groff - LaTeX fans hate him" on <https://www.youtube.com/watch?v=CzUHjtGBdZs> [neatroff]: <https://github.com/aligrudi/neatroff>
