How can I use the slanted variant of the libertine font?

Question

In standard packages with the Texlive distribution on Debian 7 (Wheezy), I was able to produce slanted text with the Linux Libertine font by calling text as \textsl{slanted text here}.

I have upgraded to Debian 8 (Jessie) and it seems the Libertine package does not support slanted text anymore. Everywhere I call \textsl{} the output is merely italic. I have installed all the variants of Libertine on my operating system (as OTF) and I have access to Linux Libertine Display Slanted O through LibreOffice and other programs.

This is most regrettable, because I use slanted text a lot for keywords in large scientific documents.

Is there a way for me to configure LaTeX so that I have access to slanted Libertine, or a similar font that fits well within regular Libertine text?

MWE which produces only italic when compiled with pdflatex:

\documentclass{article}
\usepackage{libertine}

\begin{document}

Here is some \textit{italic} text,
and what should be \textsl{slanted} text.

\end{document}

Answer 1

There is no slanted font in the Linux Libertine distribution. You can do like LibreOffice does and fake the slanting geometrically.

\documentclass{article}
\usepackage{libertine}

\makeatletter
\setmainfont[
  Extension=.otf,
  Numbers        = {\libertine@figurealign,\libertine@figurestyle},
  UprightFont    = *_R,
  ItalicFont     = *_RI,
  BoldFont       = *_\libertine@boldstyle,
  BoldItalicFont = *_\libertine@boldstyle I,
  SlantedFont    = *_R,
  SlantedFeatures = {FakeSlant=0.25},
]{\libertine@base}
\makeatother

\begin{document}

Here is some \textit{italic} text,
and what should be \textsl{slanted} text.

\end{document}

Answer 2

Another option is to use Bruno's \slantbox (Shear transform a "box") as a substitute for \textsl. I have set the default slant to 0.2.

\documentclass{article}
\newsavebox\foobox
\newcommand{\slantbox}[2][.2]{\mbox{%
        \sbox{\foobox}{#2}%
        \hskip\wd\foobox
        \pdfsave
        \pdfsetmatrix{1 0 #1 1}%
        \llap{\usebox{\foobox}}%
        \pdfrestore
}}
\def\textsl#1{\slantbox{#1}}
\usepackage{libertine}

\begin{document}

Here is some \textit{italic} text,
and what should be \textsl{slanted} text.

\end{document}

Answer 3

The solution is to install the libertine-legacy (TeX) package, as @user51830 pointed out. The current (2015-08) libertine package is a dummy package which points to libertineotf or libertine-type1 depending on the compiler that calls it, but even though it “serves the purpose” of libertine-legacy, it does not replace it fully and in particular it does not contain slanted text.

If you want slanted libertine text, but only want to use pdflatex, you need libertine-legacy. On Debian 8 there is no deb package for this and the install needs to be done manually. This does not require removing any existing TeX or Debian package from the system.

The following procedure worked for me (although some steps are probably dispensable):

1. Download a libertine-legacy.tds.zip archive from an old mirror. (no, the libertine-legacy.zip package from CTAN will not work!) I found mine on the UChicago website through Google. Extract all of its files in your local TEXMF path (mine was at /usr/local/share/texmf/).
2. Among these new files, install all the fonts in fonts/type1/public/libertine-legacy to your operating system (by double-clicking on them or by copying them to your ~∕.fonts/ folder).
3. Check that your new libertine-legacy package takes precedence over any other libertine instance on your system by typing kpsewhich libertine.sty which should return the path to your freshly-added files. If it does not, delete all the intruders.
4. Run mktexlsr and then updmap-sys enable Map libertine.map (you may need administrator rights for this).

You should now be able to compile the following file with pdflatex:

\documentclass{article}
\usepackage[T1]{fontenc} % note this addition: else libertine will default
                         % to OT1 fonts, and will fail
\usepackage{libertine}

\begin{document}

Here is some \textit{italic} text,
and what should be \textsl{slanted} text.

\end{document}