docs: format TeX logos using hologo pkg

[muzimuzhi]

Motivation for this change

Correct unformatted TeX logos in manual. For logos not built-in to LaTeX2e, use \hologo{<logo>} from hologo package.

Addresses #1466 (comment) by @Mo-Gul.

Checklist

Please signoff your commits to explicitly state your agreement to the Developer Certificate of Origin. If that is not possible you may check the boxes below instead:

• Code changes are licensed under GPLv2 + LPPLv1.3c
• Documentation changes are licensed under FDLv1.2

[Copilot]

Pull request overview

Updates the PGF/TikZ manual sources to consistently typeset TeX-engine/distribution logos (e.g., LuaTeX, e-TeX, TeX Live) using hologo, and fixes a few remaining plain “TeX” mentions to use the proper \TeX{} logo.

Changes:

• Add hologo to the manual preamble so \hologo{...} is available throughout the manual.
• Replace several unformatted “LuaTeX / e-TeX / TeX Live” occurrences with \hologo{...} and “TeX” with \TeX{} where appropriate.
• Add an Unreleased changelog entry describing the manual typo/logo fixes.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
doc/generic/pgf/pgfmanual-en-pgfsys-commands.tex	Replace plain “TeX” mentions with \TeX{} in command documentation text.
doc/generic/pgf/pgfmanual-en-math-parsing.tex	Use \hologo{eTeX} for e-TeX logo formatting.
doc/generic/pgf/pgfmanual-en-main-preamble.tex	Load hologo in the manual preamble to support \hologo{...} usage.
doc/generic/pgf/pgfmanual-en-library-profiler.tex	Format LuaTeX logo via \hologo{LuaTeX} in a footnote.
doc/generic/pgf/pgfmanual-en-installation.tex	Format TeX Live logo via \hologo{TeXLive}.
doc/generic/pgf/pgfmanual-en-gd-ogdf.tex	Format LuaTeX logo via \hologo{LuaTeX}.
doc/generic/pgf/pgfmanual-en-gd-algorithms-in-c.tex	Format TeX Live logo via \hologo{TeXLive}.
doc/generic/pgf/pgfmanual-en-dv-formats.tex	Replace plain “TeX” with \TeX{} in data format documentation.
doc/generic/pgf/CHANGELOG.md	Add an Unreleased entry for the manual/logo typo fixes.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[muzimuzhi]

Logo formatting is done "blindly". I haven't checked whether what's said here still holds.

[Mo-Gul]

other "TeX" instances I found in the manual.

• Con\TeX t
• \LaTeX
• \LaTeXe
• Lua\TeX --> either always use this or \hologo{LuaTeX}. I'd go without package, because it is less work (if not all other TeX instances will use the package command)
• Lua(\TeX)
• MiK\TeX
• pdf\LaTeX
• pdf\TeX
• plain\TeX --> harmonize with the next ones (all except the capital one exist in package)
• plain-\TeX{}
• plain \TeX{}
• Plain \TeX --> (Sometimes used at the beginning of a sentence. If it should remain capital there, don't replace blindly. Also used in a heading ...)

Interestingly I didn't find any of

• XeTeX
• XeLaTeX

Aren't say supported anywhere or is there really just no need to mention that somewhere?

[Mo-Gul]

I think I remember we had a discussion on how to typeset these things a few years ago already.

Since Henry already stated that he'd keep \TeX and LaTeX untouched, I'd suggest to change it at least from e.g. \TeX\ to \TeX{} and similar like \TeX-style to \TeX{}-style. Then in future we can very very easy find the relevant entries even without regex magic to filter out "plaint text commented heading lines".

[Mo-Gul]

I find it cumbersome to surround all the instances with \hologo. So alternatively we could use bxtexlogo or hvlogos instead, where the commands exist directly like \LuaTeX.

Or is that too much overhead compared to the hologo package?

[muzimuzhi]

other "TeX" instances I found in the manual.

• Con\TeX t
• \LaTeX
• \LaTeXe
• Lua\TeX --> either always use this or \hologo{LuaTeX}. I'd go without package, because it is less work (if not all other TeX instances will use the package command)
• Lua(\TeX)
• MiK\TeX
• pdf\LaTeX
• pdf\TeX
• plain\TeX --> harmonize with the next ones (all except the capital one exist in package)
• plain-\TeX{}
• plain \TeX{}
• Plain \TeX --> (Sometimes used at the beginning of a sentence. If it should remain capital there, don't replace blindly. Also used in a heading ...)

@Mo-Gul I should have addressed all of these, using \hologo{<name>} syntax. Although cumbersome, the braced form \hologo{...} saves me the trouble of deciding between using \TeX\ or \TeX{}.

• \TeX, \LaTeX, and \LaTeXe are untouched
• Various plain \TeX forms unified to \hologo{plainTeX}, without dash
• Reword {plainenvironment} env contents so now the capital form Plain \TeX is never used at the beginning of a sentence, but only in section titles.

Interestingly I didn't find any of

• XeTeX
• XeLaTeX

Aren't say supported anywhere or is there really just no need to mention that somewhere?

Mentioned as |xetex|, in lowercase and verbatim. Introduced in #1466. Can be changed to use logo forms.