[XeTeX] Primes and unicode-math.

[Khaled Hosny]

On Sun, Oct 10, 2010 at 04:19:25PM -0400, Cole Leahy wrote:
> This is more or less a continuation of the thread at http://tug.org/pipermail/
> xetex/2010-October/018741.html. Unfortunately, I don't know how to include this
> message in that thread, since I don't actually receive email from this list.
> Please excuse me. Anyway, Khaled's suggestion from that thread worked; using
> the following source, Greek and Latin characters appear in the desired font
> within math mode.
> 
> \documentclass{article}
> \usepackage{amsmath}
> \usepackage{unicode-math}
> \setmainfont{Linux Libertine O}
> \setmathfont{xits-math.otf}
> \setmathfont[range=\mathit/{latin,Latin,greek,Greek}]{Linux Libertine O Italic}
> \begin{document}
> Since $X$ is club in $\kappa$, so is the derivative $X\prime$. Therefore each
> superset of $X'$ is stationary. Blah blah. It follows that $\{\xi < \kappa : \
> xi \text{ is Mahlo} \} \supseteq \{\xi < \kappa : \xi \text{ is the } \xi^{\
> text{th}} \text{ Mahlo} \}$ is stationary in $\kappa$, and that $\kappa$ is the
> $\kappa^{\hspace{0.2mm}\text{th}} \text{ Mahlo}$.
> \end{document}
> 
> Yet, as you'll see if you compile it, the primes are tiny and misplaced. (The
> related thread from a few days ago, at http://tug.org/pipermail/xetex/
> 2010-October/018636.html, isn't helping me here.) Furthermore, if in the final
> line of the preamble one uses, say, Minion Pro instead of Libertine, the primes
> vanish. If the issue is that unicode-math is looking for the prime glyph in
> Libertine (or Minion, as the case may be) how can I tell it to look in XITS
> instead?

This indeed what is happening, I'm not sure whether it is a bug or
feature, but you can explicitly ask for primes to come from XITS:

  \setmathfont[range=\prime]{xits-math.otf}

(should be after the libertine line)

> Also, as I feared would happen, the kerning on exponents, commas, and
> the like isn't ideal. Is there a way to get around this that's more efficient
> than tweaking hspace as needed?

This is because regular OpenType fonts lack italic correction, and the
only way to include it is by editing the font itself (it is not a hard
job; can be take an hour or in FontForge depending on the number of
glyphs).

Regards,
 Khaled


-- 
 Khaled Hosny
 Arabic localiser and member of Arabeyes.org team
 Free font developer