path: root/luaotfload.dtx

% \iffalse meta-comment
%
% Copyright (C) 2009 by Elie Roux <elie.roux@telecom-bretagne.eu>
%
% This work is under the CC0 license.
%
% This work consists of the main source file luaotfload.dtx
% and the derived files
%    luaotfload.sty, luaotfload.lua
%
% Unpacking:
%    tex luaotfload.dtx
%
% Documentation:
%    pdflatex luaotfload.dtx
%
%    The class ltxdoc loads the configuration file ltxdoc.cfg
%    if available. Here you can specify further options, e.g.
%    use A4 as paper format:
%       \PassOptionsToClass{a4paper}{article}
%
%
%
%<*ignore>
\begingroup
  \def\x{LaTeX2e}%
\expandafter\endgroup
\ifcase 0\ifx\install y1\fi\expandafter
         \ifx\csname processbatchFile\endcsname\relax\else1\fi
         \ifx\fmtname\x\else 1\fi\relax
\else\csname fi\endcsname
%</ignore>
%<*install>
\input docstrip.tex
\Msg{************************************************************************}
\Msg{* Installation}
\Msg{* Package: luaotfload 2009/08/10 v1.03 ConTeXt font loading system}
\Msg{************************************************************************}

\keepsilent
\askforoverwritefalse

\let\MetaPrefix\relax

\preamble
This is a generated file.

Copyright (C) 2009 by Elie Roux <elie.roux@telecom-bretagne.eu>

This work is under the CC0 license.

This work consists of the main source file luaotfload.dtx
and the derived files
    luaotfload.sty, luaotfload.lua

\endpreamble

\let\MetaPrefix\DoubleperCent


\generate{%
  \usedir{tex/luatex/luaodfload}%
  \file{luaotfload.sty}{\from{luaotfload.dtx}{package}}%
}

% The following hacks are to generate a lua file with lua comments starting by
% -- instead of %%

\def\MetaPrefix{-- }

\def\luapostamble{%
  \MetaPrefix^^J%
  \MetaPrefix\space End of File `\outFileName'.%
}

\def\currentpostamble{\luapostamble}%

\generate{%
  \usedir{tex/luatex/luaotfload}%
  \file{luaotfload.lua}{\from{luaotfload.dtx}{lua}}%%
}

\obeyspaces
\Msg{************************************************************************}
\Msg{*}
\Msg{* To finish the installation you have to move the following}
\Msg{* files into a directory searched by TeX:}
\Msg{*}
\Msg{*     luaotfload.sty, luaotfload.lua}
\Msg{*}
\Msg{* Happy TeXing!}
\Msg{*}
\Msg{************************************************************************}

\endbatchfile
%</install>
%<*ignore>
\fi
%</ignore>
%<*driver>
\NeedsTeXFormat{LaTeX2e}
\ProvidesFile{luaminimalotf.drv}%
  [2009/08/10 v1.03 ConTeXt font loading system]%
\documentclass{ltxdoc}
\EnableCrossrefs
\CodelineIndex
\begin{document}
  \DocInput{luaotfload.dtx}%
\end{document}
%</driver>
% \fi
%
% \CheckSum{0}
%
% \CharacterTable
%  {Upper-case    \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
%   Lower-case    \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
%   Digits        \0\1\2\3\4\5\6\7\8\9
%   Exclamation   \!     Double quote  \"     Hash (number) \#
%   Dollar        \$     Percent       \%     Ampersand     \&
%   Acute accent  \'     Left paren    \(     Right paren   \)
%   Asterisk      \*     Plus          \+     Comma         \,
%   Minus         \-     Point         \.     Solidus       \/
%   Colon         \:     Semicolon     \;     Less than     \<
%   Equals        \=     Greater than  \>     Question mark \?
%   Commercial at \@     Left bracket  \[     Backslash     \\
%   Right bracket \]     Circumflex    \^     Underscore    \_
%   Grave accent  \`     Left brace    \{     Vertical bar  \|
%   Right brace   \}     Tilde         \~}
%
% \GetFileInfo{luaotfload.drv}
%
% \title{The \textsf{luaotfload} package}
% \date{2009/08/10 v1.03}
% \author{Elie Roux \\ \texttt{elie.roux@telecom-bretagne.eu}}
%
% \maketitle
%
% \begin{abstract}
% Con\TeX t font loading system, providing the possibility to load OTF fonts
% with a lot of features, and the Xe\TeX\ font loading syntax.
% \end{abstract}
%
% \tableofcontents
%
% \section{Documentation}
% 
% \subsection{Introduction}
%
% Font management and installation has always been painful with \TeX\ (and
% even more with \LaTeX ). A lot of files are needed for one font (tfm, pfb,
% map, fd, vf), and they are limited to 256 characters. But the font world has
% evolved since, and new standard types of fonts have appeared, like
% \textsf{truetype} or \textsf{opentype} fonts. These fonts can contain a lot
% of characters, and have some functionalities (ligatures, old-style numbers,
% small capitals, etc.). They are everywhere, as the system fonts and most
% modern text softwares fonts are of this type. Until now the (almost) only
% way to use them with \TeX\ was to use them with Xe\TeX .
%
% Unlike Xe\TeX , Lua\TeX\ does not provide facilities for these fonts by
% default, but it provides a way to hook lua code in some points of the \TeX\
% algorithm, for instance we can improve the font loading system; this is what
% we do in this package.
%
% This package is quite low-level, and should be loaded directly in the macro
% package, like it is in Con\TeX t. Sadly, Plain and \LaTeX\ are frozen and
% it's even impossible to adapt them to the new engines. 
%
% \subsection{Con\TeX t files needed}
%
% This package is a wrapper for several files taken from the Con\TeX t macro
% package. The philosophy is to let Con\TeX t do all the implementation and
% update these files from time to time. To do so we did not modify the files
% taken from Con\TeX t, we only changed their names to prevent name clashes.
% You can thus update the font system of this package simply by updating the
% files taken from Con\TeX t, without (theorically) changing the \texttt{.sty}
% file nor the main \texttt{.lua} file.
%
% The Con\TeX t files are renamed by adding the prefix \texttt{otfl-} to them
% (\texttt{otfl} as \texttt{OTF L}oad).The files are:
%
% \begin{itemize}
% \item \texttt{luat-dum.lua}
% \item \texttt{data-con.lua}
% \item \texttt{node-ini.lua}
% \item \texttt{node-inj.lua}
% \item \texttt{node-fnt.lua}
% \item \texttt{node-dum.lua}
% \item \texttt{font-ini.lua}
% \item \texttt{font-tfm.lua}
% \item \texttt{font-cid.lua}
% \item \texttt{font-ott.lua}
% \item \texttt{font-otf.lua}
% \item \texttt{font-otd.lua}
% \item \texttt{font-oti.lua}
% \item \texttt{font-otb.lua}
% \item \texttt{font-otn.lua}
% \item \texttt{font-ota.lua}
% \item \texttt{font-otc.lua}
% \item \texttt{font-def.lua}
% \item \texttt{font-xtx.lua}
% \item \texttt{font-map.lua}
% \item \texttt{font-dum.lua}
% \end{itemize}
% 
% \subsection{Troubleshooting}
%
% If you encounter problems with some fonts, please first update to the latest version of this package before reporting a bug, as this package is under active development.
%
% A very common problem is the lack of features for some otf fonts even when specified. It can be related to the fact that some fonts do not provide features for the |dflt| script, which is the default one in this package, so you may have to specify the script in the command line, for example:
%
% |\font\myfont = MyFont.otf:script=latn;+liga;|
%
% \section{\texttt{luaotfload.lua}}
%
% \iffalse
%<*lua>
% \fi
%
%    First some usual initializations.
%
%    \begin{macrocode}
luaotfload          = { }

luaotfload.module = {
    name          = "luaotfload",
    version       = 1.03,
    date          = "2009/08/10",
    description   = "ConTeXt font loading system.",
    author        = "Elie Roux & Hans Hagen",
    copyright     = "Elie Roux",
    license       = "CC0"
}

luatextra.provides_module(luaotfload.module)

%    \end{macrocode}
%
%    We load the Con\TeX t files with this function. It automatically adds the
%    \texttt{otfl-} prefix to it, so that we call it with the actual Con\TeX t
%    name.
%
%    \begin{macrocode}


function luaotfload.loadmodule(name)
    local foundname = kpse.find_file('otfl-'..name,"tex")
    if not foundname then
      luatextra.module_error('luaotfload', string.format('file otfl-%s not found.', name))
      return 
    end
    dofile(foundname)
end

%    \end{macrocode}
%
%    The following functions are made to map Con\TeX t functions to
%    \textsf{luaextra} functions.
%
%    \begin{macrocode}

string.strip = string.stripspaces

file = fpath
file.extname = fpath.suffix

%    \end{macrocode}
%
%    These are small functions that are not already in \textsf{luatextra}.
%
%    \begin{macrocode}

local splitters_s, splitters_m = { }, { }

function lpeg.splitat(separator,single)
    local splitter = (single and splitters_s[separator]) or splitters_m[separator]
    if not splitter then
        separator = lpeg.P(separator)
        if single then
            local other, any = lpeg.C((1 - separator)^0), lpeg.P(1)
            splitter = other * (separator * lpeg.C(any^0) + "")
            splitters_s[separator] = splitter
        else
            local other = lpeg.C((1 - separator)^0)
            splitter = other * (separator * other)^0
            splitters_m[separator] = splitter
        end
    end
    return splitter
end

function table.compact(t)
    if t then
        for k,v in next, t do
            if not next(v) then
                t[k] = nil
            end
        end
    end
end

function table.sortedhashkeys(tab) -- fast one
    local srt = { }
    for key,_ in next, tab do
        srt[#srt+1] = key
    end
    table.sort(srt)
    return srt
end

function table.reverse_hash(h)
    local r = { }
    for k,v in next, h do
        r[v] = string.lower(string.gsub(k," ",""))
    end 
    return r
end 

function table.reverse(t)
    local tt = { }
    if #t > 0 then
        for i=#t,1,-1 do
            tt[#tt+1] = t[i]
        end
    end
    return tt
end

%    \end{macrocode}
%
%    We start loading some lua files. These two are some code not used by
%    Con\TeX t at all that allow other modules to be used, it provides some
%    low-level Con\TeX t functions.
%
%    \begin{macrocode}

luaotfload.loadmodule('luat-dum.lua') -- not used in context at all
luaotfload.loadmodule('data-con.lua') -- maybe some day we don't need this one

%    \end{macrocode}
%
%    This one is for node support.
%
%    \begin{macrocode}

luaotfload.loadmodule('node-ini.lua')

%    \end{macrocode}
%
%    By default Con\TeX t takes some private attributes for internal use. With
%    Plain and \LaTeX\ we can't do so, we use |\newluaattribute|. This
%    functions overrides a function defined in the previous module that
%    returns the number of a private attribute. We allocate new attributes in
%    the \texttt{.sty} file, and this function returns their number. Like this
%    we don't need any private attribute, and this package is compatible with
%    the others. We use the |otfl@| prefix for attributes.
%
%    \begin{macrocode}

function attributes.private(name)
    local number = tex.attributenumber['otfl@'..name]
    if not number then 
        luatextra.module_error('luaotfload', string.format('asking for attribute %s, but not declared. Please report to the maintainer of luaotfload.', name))
    end
    return number
end

%    \end{macrocode}
%
%    Some more modules. We don't load neither \texttt{font-enc.lua} nor
%    \texttt{font-afm.lua} as it will never be used here.
%
%    \begin{macrocode}

luaotfload.loadmodule('node-res.lua')
luaotfload.loadmodule('node-inj.lua')
luaotfload.loadmodule('node-fnt.lua')
luaotfload.loadmodule('node-dum.lua')

luaotfload.loadmodule('font-ini.lua')
luaotfload.loadmodule('font-tfm.lua')
luaotfload.loadmodule('font-cid.lua')
luaotfload.loadmodule('font-ott.lua')
luaotfload.loadmodule('font-otf.lua')
luaotfload.loadmodule('font-otd.lua')
luaotfload.loadmodule('font-oti.lua')
luaotfload.loadmodule('font-otb.lua')
luaotfload.loadmodule('font-otn.lua')
luaotfload.loadmodule('font-ota.lua')
luaotfload.loadmodule('font-otc.lua')

%    \end{macrocode}
%
%    \texttt{font-def.lua} calls the function \texttt{callback.register} to
%    register its callbacks. We override it with a dumb function so that it
%    does not register any callback. We will register the callbacks later.
%
%    \begin{macrocode}

do
  local temp = callback.register
  callback.register = function (...)
    return
  end 
  luaotfload.loadmodule('font-def.lua')
  callback.register = temp
end

luaotfload.loadmodule('font-xtx.lua')
luaotfload.loadmodule('font-map.lua')
luaotfload.loadmodule('font-dum.lua')

%    \end{macrocode}
%
%    This is a small patch that prevents errors in some \LaTeX\ files.
%
%    \begin{macrocode}

fonts.enc.known = {}

%    \end{macrocode}
%
%    Finally two functions 
%
%    \begin{macrocode}

function luaotfload.register_callbacks()
    callback.add('pre_linebreak_filter', nodes.simple_font_handler, 'luaotfload.pre_linebreak_filter')
    callback.add('hpack_filter',         nodes.simple_font_handler, 'luaotfload.hpack_filter')
    callback.reset('define_font')
    callback.add('define_font', fonts.define.read, 'luaotfload.define_font', 1)
    callback.add('find_vf_file', fonts.vf.find, 'luaotfload.find_vf_file')
end

function luaotfload.unregister_callbacks()
    callback.remove('pre_linebreak_filter', 'luaotfload.pre_linebreak_filter')
    callback.remove('hpack_filter', 'luaotfload.hpack_filter')
    callback.remove('define_font', 'luaotfload.define_font')
    callback.remove('find_vf_file', 'luaotfload.find_vf_file')
end
%    \end{macrocode}
% \iffalse
%</lua>
% \fi
%
% \section{\texttt{luaotfload.sty}}
%
% \iffalse
%<*package>
% \fi
%
%    Classical Plain+\LaTeX\ package initialization.
%
%    \begin{macrocode}
\csname ifluaotfloadloaded\endcsname
\let\ifluaotfloadloaded\endinput

\expandafter\ifx\csname ProvidesPackage\endcsname\relax
  \input luatextra.sty
\else
  \NeedsTeXFormat{LaTeX2e}
  \ProvidesPackage{luaotfload}%
    [2009/08/10 v1.03 ConTeXt font loading system]
  \RequirePackage{luatextra}
\fi

\expandafter\edef\csname otfl@AtEnd\endcsname{%
  \catcode64 \the\catcode64\relax
}

\catcode64 11

%    \end{macrocode}
%
%    The attributes are allocated here. The |otfl@| prefix is added to prevent
%    name collision.
%
%    \begin{macrocode}

\newluaattribute\otfl@state
\newluaattribute\otfl@markbase
\newluaattribute\otfl@markdone
\newluaattribute\otfl@markmark
\newluaattribute\otfl@cursbase
\newluaattribute\otfl@curscurs
\newluaattribute\otfl@cursdone
\newluaattribute\otfl@kernpair
\newluaattribute\otfl@color

%    \end{macrocode}
%
%    Two small macros to register or unregister the callbacks. Without the
%    callbacks this package is totally turned off.
%
%    \begin{macrocode}

\def\otfl@off{
\luadirect{luaotfload.unregister_callbacks()}
}

\def\otfl@on{
\luadirect{luaotfload.register_callbacks()}
}

%    \end{macrocode}
%
%    We load the |lua| file, and we turn the package on.
%
%    \begin{macrocode}

\luaUseModule{luaotfload}

\otfl@on

\otfl@AtEnd
%    \end{macrocode}
% \iffalse
%</package>
% \fi
% \Finale
\endinput