This closed question prompts me to propose a more general question and a solution I don't think has been demonstrated here.

When compiling with LuaLaTeX and using Unicode input, how do you set up a fallback font for specific Unicode characters that are absent from the main font?

I would welcome other approaches or critiques of the one I demonstrate.

  • You definitely get an up-vote from me.
    – Gaussler
    Jan 23 '15 at 19:46

We can define a command to switch to a fallback font using fontspec.

Then we can use newunicodechar to map the missing Unicode characters to a command that switched to the fallback font for those characters.

\usepackage{fontspec, newunicodechar}
\setmainfont{PT Serif}
\newfontfamily{\fallbackfont}{Linux Libertine O}[Scale=MatchLowercase]

Hellɔ woϱld.

enter image description here

Output of pdffonts showing that both fonts are used:

name                                 type              emb sub uni object ID
------------------------------------ ----------------- --- --- --- ---------
NUOAQT+PTSerif-Regular               CID TrueType      yes yes yes      4  0
UAEGUX+LinLibertineO                 CID Type 0C       yes yes yes      5  0


We could also define a general command for setting up missing characters. It takes an optional argument which defaults to \textfallback, but a different font could be inserted in case an additional fallback font was needed.

  • 3
    \DeclareTextFontCommand\textfallback{\fallbackfont} is the official way of defining \textfallback.
    – Manuel
    Jan 23 '15 at 15:08
  • 1
    LaTeS kernel, IIRC.
    – Manuel
    Jan 23 '15 at 15:13
  • 1
    @Manuel Thank you for improving the answer! I found the command on line 3721 of latex.ltx. I edited the answer to use this. Jan 23 '15 at 15:26
  • 3
    I am wondering if this could be automated somehow, so that whenever fontspec stumbles upon a character that is not in the font, it prints that character with \textfallback instead.
    – Gaussler
    Jan 23 '15 at 19:50
  • 1
    @Gaussler This might interest you: tex.stackexchange.com/questions/53599/… Jan 23 '15 at 20:17

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.