# Fontspec transparency problems

I'm using this minimal document to test transparency:

\documentclass[11pt]{article}
\usepackage{xunicode, xltxtra}
\defaultfontfeatures{Mapping=tex-text}
\usepackage{fontspec}
\usepackage[usenames]{xcolor}

\begin{document}
\fontspec[Color=red,Opacity=0.1,Scale=12]{Helvetica}Test
\end{document}


The rendered text is fully opaque when typeset through TeXShop with TeXLive 2011 on a MacOS Lion. Is this a known issue?

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This document simply fails to compile for me. (Seems to require calc) (TeXLive 2011, Mac 10.6). (TeXShop has nothing to do with this, I would assume.) – Alan Munn Mar 11 '12 at 22:24
@AlanMunn I don't why, the document is compiling normally for me. – ipavlic Mar 11 '12 at 22:26
This is a XeLaTeX problem. Compiling the same document with LuaLaTeX gets the opacity right. – Alan Munn Mar 11 '12 at 22:38
You should load xunicode after fontspec or it will not setup its definitions correctly. Actually todo it is enough to either load xtlxtra or fontspec. Both will load xunicode at the correct place. – Ulrike Fischer Mar 12 '12 at 7:17

From the fontspec manual (p.16):
Transparency is supported by LuaLaTeX and by XeLaTeX with the xdv2pdf driver (Mac OS X only); XeLATeX with the xdvipdfmx driver does not support this feature.
TeXShop has an engine for compiling XeLaTeX with the xdv2pdf driver. You can activate it by dragging it from the ~/Library/TeXShop/Engines/Inactive folder to the Engines folder. Compiling your document with this driver gives the desired transparency.
I don't think, however, that this driver is actively supported anymore, (the xdvipdfmx driver is the default) so it's unclear if using it will affect other things.