\reflectbox ?

[ctrlcctrlv]

I have macros for \LaTeX and \SILE. Is it possible to typeset the XeTeX and XeLaTeX logos, which has flipped ‹E›'s?

I suppose I need to make a custom font with a flipped E, Ǝ, if it doesn't exist in the font? Or...

XƎLaTeX / XƎTeX ?

[alerque]

Is it actually mirrored or would a 180 spin work just as well?

[ctrlcctrlv]

Hmm. I mean, it might be noticeable in some fonts, if the E bar is not exactly centered.

[DavidLRowe]

U+018E perhaps? Ǝ

[ctrlcctrlv]

Thanks @DavidLRowe , I mentioned it in the first post :-)

I suppose I need to make a custom font with a flipped E, Ǝ, if it doesn't exist in the font? Or...

I'm trying to make a logos package for SILE. In LaTeX it's pretty normal to typeset the logo in any font, so that's why I'm asking. It seems more fonts have U+018E than I thought: Gentium Pro, EB Garamond, Noto Serif, etc., all have it, so maybe it's not such a big deal to try to support those without. After all, you have to use a robust text face with SILE to really take advantage of it, so I'm not sure I care about people who aren't. ;-)

I'll just provide -CM versions, like LaTeX-CM, which will choose Latin Modern Roman, I guess, for them. 🤷‍♂️

[simoncozens]

Implementing \reflectbox would certainly be an interesting project for anyone who wants to learn about output drivers. :-) You would want to look into how the graphics package works in xetex, since we are effectively using xetex's output backend as a library. Here's something from xetex.def that may be relevant:

\def\Gscale@start{%
  \special{pdf:btrans}%
  \special{x:scale \Gscale@x\GPT@space\Gscale@y}%
}
...
\def\Gscale@end{\special{pdf:etrans}}

Now, how do we get those specials into the PDF? libtexpdf doesn't support specials directly, so you need to look at their implementation in dvipdfmx, which you'll find here. Then it's a matter of working out which low-level libtexpdf functions you need to expose to Lua, putting those into justenoughlibtexpdf.c, and writing some routines in packages/pdf.lua to implement the specials.

[ctrlcctrlv]

@simoncozens Cool idea. For now I decided to just use Ǝ and do the rotate, but I'll keep it in mind !

Here are all the major LaTeX logos in SILE format:

https://github.com/ctrlcctrlv/sile-logos