[XeTeX] Scaling fonts in fontspec changes the relative gap in 100 °C when using siunitx

[Tobias Schoel]

Hi,

consider this minimal example:

\documentclass{minimal}

\newcommand{\phont}{Asana Math}
\newcommand{\Phont}{TeX Gyre Pagella}

\usepackage{fontspec}
\setmainfont{\Phont}
\usepackage{unicode-math}
\setmathfont{\phont}

\usepackage{siunitx}
\sisetup{%
math-celsius=℃,
text-celsius=℃,
detect-all
}

\begin{document}
\setmainfont[Scale=1]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=2]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=3]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=4]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=5]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=6]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=7]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=8]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=9]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=10]{\Phont}
\SI{100}{\celsius}

\clearpage
\renewcommand{\Phont}{TeX Gyre Pagella Bold}

\setmainfont[Scale=1]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=2]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=3]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=4]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=5]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=6]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=7]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=8]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=9]{\Phont}
\SI{100}{\celsius}

\setmainfont[Scale=10]{\Phont}
\SI{100}{\celsius}

\clearpage

\setmathfont[Scale=1]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=2]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=3]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=4]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=5]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=6]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=7]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=8]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=9]{\phont}
\(\SI{100}{\celsius}\)

\setmathfont[Scale=10]{\phont}
\(\SI{100}{\celsius}\)
\end{document}

When scaling the fonts, it seems to me, that the gap between 100 and °C 
(actually its ℃=u2103), which some fonts don't have but TeX Gyre Pagella 
and Asana Math do, gets smaller in relation to the overall size.

What is the reason for this?

bye

Toscho

-- 
Tobias Schoel
Europaschule Kairo
www.europaschulekairo.com