# [XeTeX] [Dev-luatex] Unicode-Math in LuaLaTeX and XeLaTeX

Ulrike Fischer luatex at nililand.de
Wed Dec 12 12:06:15 CET 2018

> The first issue is the usage of the staircase kerning boxes of
> opentype math fonts. They are obviously not applied in expressions
> like $f_j$ using LuaLaTeX. The index is rendered too far away from
> the glyph. If we use XeLaTeX we get the correct output.

It works okay with luatex 1.09 (miktex or dev-TeXLive), but fails in a
current texlive 2018.

> The second issue is present in both LuaLaTeX and XeLaTeX. If we
> have an index together with an exponent like j the index is rendered
> too high – in fact it is risen compared to the expression that uses
> an index only. A typical example is $f_n^j$.

The sup/sub pair is higher placed than with context. You could move it
down (at least with luatex) with

\documentclass{article}
\usepackage{unicode-math}
\setmathfont{Cambria Math}
\begin{document}
$f_n^j$

\Umathsupsubbottommax\textstyle =2pt
$f_n^j$
\end{document}

unicode-math could probably offer some option to set this.

--
Mit freundlichen Grüßen
Ulrike Fischer
mailto:luatex at nililand.de