% \iffalse meta-comment
%
% Copyright 1993 1994 1995 1996 1997 1998 1999
% The LaTeX3 Project and any individual authors listed elsewhere
% in this file.
%
% This file is part of the LaTeX2e system.
% ----------------------------------------
%
% It may be distributed under the terms of the LaTeX Project Public
% License, as described in lppl.txt in the base LaTeX distribution.
% Either version 1.0 or, at your option, any later version.
%
% \fi
%
% \iffalse
%%% From File: ltfsstrc.dtx
%% Copyright (C) 1989-97 by Frank Mittelbach and Rainer Sch\"opf.
%% Copyright (C) 1994-97 by LaTeX3 project. All rights reserved.
%
%<package>\NeedsTeXFormat{LaTeX2e}[1995/05/16]
%<package>\ProvidesPackage{tracefnt}
%<package> [1997/05/29 v3.0j Standard LaTeX package (font tracing)]
% \fi
% \ProvidesFile{ltfsstrc.dtx}
% [1997/05/29 v3.0j LaTeX Kernel (NFSS tracing)]
%
% \iffalse
%<+checkmem>\CHECKMEM
% \fi
%
% \CheckSum{1041}
%
%
%
% \changes{v3.0g}{1995/11/28}
% {documentation fixes}
% \changes{v3.0f}{1995/10/22}{Added `genb' and `sgenb' size functions
% to support new DC font naming scheme.}
% \changes{v3.0e}{1995/10/20}
% {(DPC) Modify autoload code}
% \changes{v3.0d}{1995/10/04}
% {(DPC) Modify autoload code}
% \changes{v3.0b}{1995/05/24}
% {(DPC) Fix \cs{ProvidesFile} usage}
% \changes{v3.0a}{1995/05/24}
% {(DPC) Make file from previous file, tracefnt 1995/05/16 v2.3o}
%
% \changes{v2.3m}{1994/11/18}
% {\cs{next} to \cs{reserved@f}}
% \changes{v2.3l}{1994/11/17}
% {\cs{@tempa} to \cs{reserved@a}}
% \changes{v2.3i}{1994/05/20}{Use new error command names}
% \changes{v2.3g}{1994/05/13}{Removed typeouts as
% \cs{ProvidesPackage} writes to log.}
% \changes{v2.3e}{1994/04/27}{Corrected item that was forgotten
% in last change.}
% \changes{v2.3d}{1994/04/18}{Changed to new error/warning scheme}
% \changes{v2.3a}{1994/01/17}{New math font setup}
% \changes{v2.2a}{1993/11/11}{Option concept added for LaTeX2e}
% \changes{v2.1j}{1993/09/15}{Corrected spelling of \cs{noxpand}.}
% \changes{v2.1i}{1993/09/02}{Corrected name of sgen size function.}
% \changes{v2.1h}{1993/07/16}{Changed layout of info messages}
% \changes{v2.1b}{1993/03/18}
% {Changed all \cs{@tempdimb} in \cs{@tempdimx}
% to avoid killing \cs{numberline}}
% \changes{v2.1b}{1993/03/18}
% {Changed all \cs{@tempdima} in \cs{@tempdimb}
% to avoid killing \cs{numberline}}
% \changes{v1.0l}{1990/04/01}{Part of code moved to fam.dtx.}
% \changes{v1.0k}{1990/03/14}{Added code for TeX3.}
% \changes{v1.0h}{1990/01/18}{\cs{tracingfonts} meaning changed.}
%
% \newcommand\module[1]{\texttt{#1}}
% \providecommand{\dst}{\textsc{DocStrip}}
% \newcommand\Loption[1]{\texttt{#1}}
%
% \GetFileInfo{ltfsstrc.dtx}
% \title{The \texttt{tracefnt} package\thanks
% {This file has version number \fileversion, dated
% \filedate.} \\
% for use with the new font selection scheme}
% \author{Frank Mittelbach \and Rainer Sch\"opf}
%
%
% \maketitle
%
% \section{Introduction}
%
% This package contains the code for tracing font loading and font
% changes. It basically overlays some of the low-level functions of
% NFSS with additional code used for tracing.
%
% The package accepts the following options:
% \begin{description}
% \item[errorshow] Write all information about font changes etc.\
% only to the transcript file unless an error happens. This means
% that information about font substitution will not be shown on the
% terminal.
%
% \item[warningshow] Show all NFSS warnings on the terminal. This
% setting corresponds to the default behaviour of NFSS if the
% \texttt{tracefnt} package is \emph{not} loaded!
%
% \item[infoshow] Show all NFSS warning and all NFSS info
% messages (that are normally only written to the transcript file)
% also on the terminal. This is the default if the \texttt{tracefnt}
% package is loaded.
%
% \item[debugshow] In addition to \texttt{infoshow} show also
% changing of math fonts as far as possible (this option can produce a
% large amount of output.
%
% \item[loading] Show the name of external fonts when they are
% loaded. This option shows only ``newly'' loaded fonts not those
% already preloaded in the format or the class file before the
% \texttt{tracefnt} package became active.
%
% \item[pausing]
% Turn all font warnings into errors so that \LaTeX{} will stop.
%
% \end{description}
%
%
% \StopEventually{}
%
% \section{A driver for this document}
%
% The next bit of code contains the documentation driver file for
% \TeX{}, i.e., the file that will produce the documentation you
% are currently reading. It will be extracted from this file by the
% \dst{} program.
%
% When this file is processed directly by \LaTeX{} this will
% produce the documentation as well.
%
% \begin{macrocode}
%<*driver>
\documentclass{ltxdoc}
%\OnlyDescription % comment out for implementation details
\begin{document}
\DocInput{ltfsstrc.dtx}
\end{document}
%</driver>
% \end{macrocode}
%
%
% \section{The Implementation}
%
% \begin{quote}
% \textbf{Warning:} Read the macro documentation with a grain of
% salt. It is still basically the documentation from the first NFSS
% release and therefore in some cases probably not completely
% accurate.
% \end{quote}
%
% If we are making a package file it is a good idea to test whether
% we are running under 2e.
% This code is actually placed at the very beginning of this file
% for easier maintenance, thus commented out here.
% \begin{macrocode}
%<*package>
%\NeedsTeXFormat{LaTeX2e}
%\ProvidesPackage{tracefnt}[??/??/?? v?.??
% Standard LaTeX package (font tracing)]
%</package>
% \end{macrocode}
%
%
% The \texttt{debug} module makes use of commands contained in a
% special package file named \texttt{trace.sty}.\footnote{This package
% is not in distribution at the moment (and probably doesn't any
% longer work). Think of this part of the code as being historical
% artefacts.}
% \begin{macrocode}
%<+debug> \input trace.sty
% \end{macrocode}
%
%
% \section{Handling Options}
%
% \begin{macro}{\tracingfonts}
% Here is the definition of the integer register for the font
% trace. As a default in a package file we use $1$ to give error
% messages if fonts are substituted. If this code is used for
% debugging or tracing reasons in the format file (i.e.\ in
% \texttt{fam.dtx}) we use $0$ as the default. But if no font
% trace is used we build a definition that will produce a warning
% message.
% \changes{v1.0l}{1990/04/01}
% {Check if \cs{tracingfonts} already defined.}
% \changes{v1.0o}{1990/04/01}
% {Check if \cs{tracingfonts} defined removed again.}
% \begin{macrocode}
%<*2ekernel|autoload>
\def\tracingfonts{%
\@font@warning{Command \noexpand\tracingfonts
not provided.\MessageBreak
Use the `tracefnt' package.\MessageBreak Command found:}%
\count@}
%</2ekernel|autoload>
% \end{macrocode}
% The |\count@| in the line above will remove the number after
% |\tracingfonts|. Note that this definition will be overwritten be
% the next line if one of these modules are included.
% \begin{macrocode}
%<*package,trace,debug>
\newcount\tracingfonts
\tracingfonts=0
%</package,trace,debug>
% \end{macrocode}
% \end{macro}
%
%
% The option \Loption{errorshow} turns off all warnings so that only
% real errors are shown. \Loption{warningshow} corresponds to the
% NFSS default (when \texttt{tracefnt} is not loaded).
% \Loption{infoshow} is the default for this package here; and
% \Loption{debugshow}, \Loption{loading}, and
% \Loption{pausing} extend the amount of information even further.
% \changes{v2.3o}{1995/05/13}
% {Use single hash mark in \cs{DeclareOption}}
% \begin{macrocode}
%<*package>
\DeclareOption{errorshow}{%
\def\@font@info#1{%
\GenericInfo{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Info: \space\space\space#1}}%
\def\@font@warning#1{%
\GenericInfo{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Warning: #1}}%
}
% \end{macrocode}
%
% \begin{macrocode}
\DeclareOption{warningshow}{%
\def\@font@info#1{%
\GenericInfo{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Info: \space\space\space#1}}%
\def\@font@warning#1{%
\GenericWarning{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Warning: #1}}%
}
% \end{macrocode}
%
% \begin{macrocode}
\DeclareOption{infoshow}{%
\def\@font@info#1{%
\GenericWarning{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Info: \space\space\space#1}}%
\def\@font@warning#1{%
\GenericWarning{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Warning: #1}}%
}
% \end{macrocode}
%
% \begin{macrocode}
\DeclareOption{loading}{%
\tracingfonts\tw@
}
% \end{macrocode}
%
% \begin{macrocode}
\DeclareOption{debugshow}{%
\ExecuteOptions{infoshow}%
\tracingfonts\thr@@
}
% \end{macrocode}
%
% \changes{v3.0j}{1997/05/29}{Replaced \texttt{\symbol{92}\symbol{92}}
% by \cs{MessageBreak}, as suggested by Donald Arseneau.}
% \begin{macrocode}
\DeclareOption{pausing}{%
\def\@font@warning#1{%
\GenericError
{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Warning: #1}%
{See the LaTeX Companion for details.}%
{I'll stop for every LaTeX Font Warning because
you requested\MessageBreak the `pausing' option
to the tracefnt package.}}%
}
% \end{macrocode}
% We make |infoshow| the default, which in turn defines
% |\font@warning| and |\font@info|.
% \begin{macrocode}
\ExecuteOptions{infoshow}
\ProcessOptions
%</package>
% \end{macrocode}
%
% We also need a default definition inside the kernel:
% \begin{macrocode}
%<*2ekernel|autoload>
\def\@font@info#1{%
\GenericInfo{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Info: \space\space\space#1}}%
\def\@font@warning#1{%
\GenericWarning{(Font)\@spaces\@spaces\@spaces\space\space}%
{LaTeX Font Warning: #1}}%
%</2ekernel|autoload>
% \end{macrocode}
%
%
% \section{Macros common to \texttt{fam.tex} and \texttt{tracefnt.sty}}
%
% In the first versions of \texttt{tracefnt.dtx} some macros of
% \texttt{fam.dtx}\footnote{This file is currently not distributed in
% documented form. Its code is part of \texttt{ltfss.dtx}.}
% were redefined to included the extra tracing
% information. Now these macros are all defined in this file (i.e.\
% removed from \texttt{fam.dtx}) and different production versions can
% be obtained simply by specifying a different set of modules to
% include when generating \texttt{ltfss.dtx}.
%
%
%
% \subsection{General font loading}
%
%
% \begin{macro}{\extract@font}
%
% This macro organizes the font loading.
% It first calls |\get@external@font|
% which will return in |\external@font| the name of the external
% font file (the \texttt{.tfm}) as it was determined by the NFSS
% tables.
% \begin{macrocode}
%<*2ekernel|package|autoload>
\def\extract@font{%
\get@external@font
% \end{macrocode}
% Then the external font is loaded and assigned to the font
% identifier stored inside |\font@name|
% (for this reason we need |\expandafter|).
% \begin{macrocode}
\global\expandafter\font\font@name\external@font\relax
% \end{macrocode}
% When tracing we typeout the internal and external font name.
% \changes{v1.0k}{1990/03/14}{Added code for TeX3.}
% \begin{macrocode}
%<*trace>
\ifnum \tracingfonts >\@ne
\@font@info{External font `\external@font'
loaded as\MessageBreak \font@name}\fi
%</trace>
% \end{macrocode}
% Finally we call the corresponding ``loading action'' macros to
% finish things. First the font is locally selected to allow the
% use of |\font| inside the loading action macros.
% \begin{macrocode}
\font@name \relax
% \end{macrocode}
% The next two lines execute the ``loading actions'' for the
% family and then for the individual font shape.
% \begin{macrocode}
\csname \f@encoding+\f@family\endcsname
\csname\curr@fontshape\endcsname
\relax
}
%</2ekernel|package|autoload>
% \end{macrocode}
% The |\relax| at the end needs to be explained.
% This is inserted to prevent \TeX{} from scanning too far
% when it is executing the replacement text of the loading
% code macros.
% \end{macro}
%
%
% \begin{macro}{\get@external@font}
% This function tries to find an external font name. It will place
% the name into the macro
% |\external@font|. If no font is found it will return the one
% that was defined via |\DeclareErrorFont|.
% \begin{macrocode}
%<*2ekernel|autoload>
\def\get@external@font{%
% \end{macrocode}
% We don't know the external font name at the beginning.
% \begin{macrocode}
\let\external@font\@empty
\edef\font@info{\expandafter\expandafter\expandafter\string
\csname \curr@fontshape \endcsname}%
\try@size@range
% \end{macrocode}
% If this failed, we'll try to substitute another size of the same
% font. This is done by the |\try@size@substitution| macro. It
% ``knows about'' |\do@extract@font|, |\font@name|, |\f@size|, and
% so on.
% \begin{macrocode}
\ifx\external@font\@empty
\try@size@substitution
\ifx\external@font\@empty
\@latex@error{Font \expandafter \string\font@name\space
not found}\@eha
\error@fontshape
\get@external@font
\fi\fi
}
%</2ekernel|autoload>
% \end{macrocode}
% \end{macro}
%
%
% \changes{v1.0j}{1990/02/18}
% {Redefine unprotected version \cs{p@selectfont}
% instead of \cs{selectfont}.}
%
%
% \begin{macro}{\selectfont}
% \changes{v1.1a}{1989/12/16}{Changed order of calls.}
% \changes{v2.3f}{1994/05/12}{Use \cs{DeclareRobustCommand}}
% The macro |\selectfont| is called whenever a font change must
% take place.
% \begin{macrocode}
%<*2ekernel|package|autoload>
\DeclareRobustCommand\selectfont
{%
% \end{macrocode}
% When \module{debug} is specified we actually want something like
% `undebug'. The font selection is now stable so that using
% |\tracingall| on some other macros will show us a lot of unwanted
% information about font loading. Therefore we disable tracing during
% font loading as long as |\tracingfonts| is less than $4$.
% \changes{v1.0m}{1990/04/05}
% {Call \cs{tracingon} only if \cs{tracingfonts} greater than 3.}
% \changes{v1.0n}{1990/05/05}{\cs{tracingon} with new syntax.}
% \begin{macrocode}
%<+debug> \pushtracing
%<+debug> \ifnum\tracingfonts<4 \tracingoff
%<+debug> \else \tracingon\p@selectfont \fi
% \end{macrocode}
% If |\baselinestretch| was redefined by the user it will not
% longer match its internal counterpart |\f@linespread|. If so we
% call |\set@fontsize| to prepare |\size@update|.
% \begin{macrocode}
\ifx\f@linespread\baselinestretch \else
\set@fontsize\baselinestretch\f@size\f@baselineskip \fi
% \end{macrocode}
% Then we generate the internal name of the font
% by concatenating {\em family}, {\em series},
% {\em shape}, and current {\em size},
% with slashes as delimiters between them.
% This is much more readable than standard
% \LaTeX's |\twfbf|, etc.
% We define |\font@name| globally, as always.
% The reason for this is explained later on.
% \changes{v2.0b}{1992/07/26}{}
% \begin{macrocode}
\xdef\font@name{%
\csname\curr@fontshape/\f@size\endcsname}%
% \end{macrocode}
% We call the macro |\pickup@font| which will load the font if
% necessary.
% \begin{macrocode}
\pickup@font
% \end{macrocode}
% Then we select the font.
% \begin{macrocode}
\font@name
% \end{macrocode}
% If |\tracingfonts| is
% greater than 2 we also show the font switch.
% We do this before |\glb@settings| is called since this
% macro might redefine |\font@name|.
% \changes{v1.0k}{1990/03/14}{Added code for TeX3.}
% \changes{v1.0i}{1990/02/16}{Changed \cs{f@size} to \cs{lcl@currsize}
% (see fam file).}
% \begin{macrocode}
%<*trace>
\ifnum \tracingfonts>\tw@
\@font@info{Switching to \font@name}\fi
%</trace>
% \end{macrocode}
% Finally we call |\size@update|. This macro is normally empty but
% will contain actions (like setting the |\baselineskip|) that have
% to be carried out when the font size, the base |\baselineskip| or
% the |\baselinestretch| have changed.
% \begin{macrocode}
\size@update
% \end{macrocode}
% A similar function is called to handle anything related to
% encoding updates. This one is changed from |\relax| by
% |\fontencoding|.
% \changes{v2.3h}{1994/05/14}{Added \cs{enc@update}}
% \begin{macrocode}
\enc@update
% \end{macrocode}
% Just before ending this macro we have to pop the tracing stack
% if it was pushed before.
% \begin{macrocode}
%<+debug> \poptracing
}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\set@fontsize}
% The macro |\set@fontsize| does the actual work. First it assigns
% new values to |\f@size|, |\f@baselineskip| and |\f@linespread|.
% \begin{macrocode}
\def\set@fontsize#1#2#3{%
\@defaultunits\@tempdimb#2pt\relax\@nnil
\edef\f@size{\strip@pt\@tempdimb}%
\@defaultunits\@tempskipa#3pt\relax\@nnil
\edef\f@baselineskip{\the\@tempskipa}%
\edef\f@linespread{#1}%
% \end{macrocode}
% For backward compatibility and for later testing within
% |\selectfont| the internal value of |\f@linespread| is passed
% back to |\baselinestretch|.
% \begin{macrocode}
\let\baselinestretch\f@linespread
% \end{macrocode}
% Additional processing will happen within |\selectfont|. For this
% reason the macro |\size@update| (which will be called in
% |\selectfont|) will be defined to be:
% \begin{macrocode}
\def\size@update{%
% \end{macrocode}
% First calculate the new |\baselineskip| and also store it in
% |normalbaselineskip|
% \begin{macrocode}
\baselineskip\f@baselineskip\relax
\baselineskip\f@linespread\baselineskip
\normalbaselineskip\baselineskip
% \end{macrocode}
% then to set up a new |\strutbox|
% \begin{macrocode}
\setbox\strutbox\hbox{%
\vrule\@height.7\baselineskip
\@depth.3\baselineskip
\@width\z@}%
% \end{macrocode}
% We end with a bit of tracing information.
% \begin{macrocode}
%<*trace>
\ifnum \tracingfonts>\tw@
\ifx\f@linespread\@empty
\let\reserved@a\@empty
\else
\def\reserved@a{\f@linespread x}%
\fi
\@font@info{Changing size to \f@size/\reserved@a
\f@baselineskip}%
\aftergroup\type@restoreinfo \fi
%</trace>
% \end{macrocode}
% When all this is processed |\size@update| redefines itself to
% |\relax| so that in later calls of |\selectfont| no extra code
% will be executed.
% \begin{macrocode}
\let\size@update\relax}%
}
% \end{macrocode}
% Instead of defining this macro internally we might speed things
% up by placing the code into a separate macro and use |\let|!
% \end{macro}
%
%
% \begin{macro}{\size@update}
% Normally this macro does nothing; it will be redefined by
% |\set@fontsize| to initiate an update.
% \begin{macrocode}
\let\size@update\relax
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\type@restoreinfo}
% This macro produces some info when a font size and/or baseline
% change will get restored.
% \changes{1.0r}{1990/08/27}{Some extra tracing info.}
% \begin{macrocode}
%<*trace>
\def\type@restoreinfo{%
\ifx\f@linespread\@empty
\let\reserved@a\@empty
\else
\def\reserved@a{\f@linespread x}%
\fi
\@font@info{Restoring size to
\f@size/\reserved@a\f@baselineskip}}
%</trace>
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\glb@settings}
% \begin{macro}{\glb@currsize}
% \changes{v2.3a}{1994/01/17}{New math font setup}
% \changes{v2.3k}{1994/11/06}{New implementation}
% The macro |\glb@settings| globally selects
% all math fonts for the current size if necessary.
% \begin{macrocode}
\def\glb@settings{%
% \end{macrocode}
% When |\glb@settings| gains control a size
% change was requested and all previous font assignments need to
% be replaced.
% Therefore the old values of the fonts are no longer needed.
% For every {\em math group\/} the new assignments are appended to
% |\math@fonts|.
% But this happens only if the |math@fonts| switch
% is set to true.
% However, we always set up the correct math sizes for script and
% scriptscript fonts since they may be needed even if we don't set
% up the whole math machinery.
%
% Here we set the math size, script size and scriptscript size.
% If the |S@|\ldots{} macro is not defined we have to first
% calculate the three sizes.
% \begin{macrocode}
\expandafter\ifx\csname S@\f@size\endcsname\relax
\calculate@math@sizes
\fi
% \end{macrocode}
% The effect of this is that |\calculate@math@sizes|
% may or may not define the |S@|\ldots{} macro. In the
% first case the next time the same size is requested
% this macro is used, otherwise |\calculate@math@sizes| is
% called again.
% This also sets the |math@fonts| switch.
% If it is true we must switch the math fonts.
% \begin{macrocode}
\csname S@\f@size\endcsname
\ifmath@fonts
%<*trace>
\ifnum \tracingfonts>\tw@
\@font@info{Setting up math fonts for
\f@size/\f@baselineskip}\fi
%</trace>
% \end{macrocode}
% Inside a group we execute the macro for the current math {\em
% version}. This sets |\math@fonts| to a list of
% |\textfont|\dots{} assignments. |\getanddefine@fonts| (which may
% be called at this point) needs the |\escapechar| parameter to be
% set to $-1$.
% \begin{macrocode}
\begingroup
\escapechar\m@ne
\csname mv@\math@version \endcsname
% \end{macrocode}
% Then we set |\globaldefs| to 1 so that all following changes are
% done globally. The math font assignments recorded in
% |\math@fonts| are executed and |\glb@currsize| is set equal to
% |\f@size|. This signals that the fonts for math in this size are
% set up.
% \begin{macrocode}
\globaldefs\@ne
\math@fonts
\let \glb@currsize \f@size
\endgroup
% \end{macrocode}
% Finally we execute any code that is supposed to happen
% whenever the math font setup changes. This register will
% be executed in local mode which means that everything that is
% supposed to have any effect should be done globally inside.
% We can't execute it within |\globaldefs\@ne| as we don't know
% what ends up inside this register, e.g., it might contain
% calculations which use some local registers to calculate the
% final (global) value.
% \begin{macrocode}
\the\every@math@size
% \end{macrocode}
% Otherwise we announce that the math fonts are not set up for this
% size.
% \begin{macrocode}
%<*trace>
\else
\ifnum \tracingfonts>\tw@
\@font@info{No math setup for
\f@size/\f@baselineskip}\fi
%</trace>
\fi
}
%</2ekernel|package|autoload>
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\baselinestretch}
% \changes{v1.0o}{1990/06/24}{Moved to tracefnt.dtx.}
% In |\selectfont| we used |\baselinestretch| as
% a factor when assigning a value to |\baselineskip|.
% We use 1 as a default (i.e.\ no stretch).
% \begin{macrocode}
%<*2ekernel|autoload>
\def\baselinestretch{1}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\every@math@size}
% \changes{v1.0u fam.dtx}{1989/12/05}{Hook \cs{every@size} added.}
% \changes{v23.k}{1994/10/23}{Renamed to \cs{every@math@size}}
% We must still define the hook |\every@math@size| we used in
% |\glb@settings|. We initialize it to nothing. It is important to
% remember that everything that goes into this hook should to global
% updates, local changes will have weird effects.
% \begin{macrocode}
\newtoks\every@math@size
\every@math@size={}
%</2ekernel|autoload>
% \end{macrocode}
% \end{macro}
%
%
%
% \subsection{Math fonts setup}
%
%
% \subsubsection{Outline of algorithm for math font sizes}
%
% \TeX{} uses the the math fonts that are current when the end of a
% formula is reached. If we don't want to keep font setups local to
% every formula (which would result in an enormous overhead, we have
% to be careful not to end up with the wrong setup in case formulas
% are nested, e.g., we need to be able to handle
% \begin{verbatim}
% $ a=b+c \mbox{ \small for all $b$ and $c\in Z$}$
%\end{verbatim}
% Here the inner formulae |b| and |c\in Z| are typeset in |\small| but
% we have to return to |\normalsize| before we reach the closing |$|
% of the outer formula.
%
% This is handled in the following way:
% \begin{enumerate}
% \item At any point in the document the global variable
% |\gbl@currsize| contains the point size for which the math fonts
% currently are set up.
%
% \item \label{it:everymath} Whenever we start a formula we compare
% its value with the local variable |\f@size| that describes the
% current text font size.
%
% \item If both are the same we assume that we can use the current
% math font setup without adjustment.
%
% \item \label{it:everymathend} If they differ we call |\gbl@settings|
% which changes the math font setup and updates |\gbl@currsize|.
% \begin{enumerate}
% \item If we are recursively inside another formula (|\if@inmath|) we
% ensure that |\gbl@settings| is executed again in the outer
% formula, so that the old setup is automatically restored.
% \item Otherwise, we set the switch |@inmath| locally to |true| so
% that all nested formulae will be able to detect that they are
% nested in some outer formula.
% \end{enumerate}
% \end{enumerate}
%
%
% The above algorithm has the following features:
% \begin{itemize}
% \item For sizes which are not containing any formula no math setup
% is done. Compared to the original algorithm of NFSS this results
% in the following savings:
% \begin{itemize}
% \item No unnecessary loading of math fonts for sizes that are not
% used to typeset any math formulae (explicit or implicit ones).
% \item No time overhead due to unnecessary changes of the math font
% setup on entrance and exit of the text font size.
% \end{itemize}
%
% \item Math font setup changes for top-level formulae will survive
% (there is no restoration after the formula) thus any following
% formula in the same size will be directly typesetable. Compared to
% original implementation in NFSS2
% the new algorithm has the overhead of one test per formula
% to see if the current math setup is valid (in the original
% algorithm the setup was always valid, thus no test was necessary).
%
% \item In nested formulae the math font setup is restored in the
% outer formula by a series of |\aftergroup| commands and checks.
% Compared to the original algorithm this involves additional checks
% ($2 \times \langle\mbox{non-math levels}\rangle$ per inner
% formula).
% \end{itemize}
%
% \subsubsection{Code for math font size setting}
%
% \begin{macro}{\check@mathfonts}
% \changes{v2.3a}{1994/01/17}{New math font setup}
% \changes{v2.3c}{1994/01/26}{Correct trace info placement}
% In the |\check@mathfonts| macros we implement the steps
% \ref{it:everymath} to \ref{it:everymathend} except that instead
% of a switch the macro |\init@restore@glb@settings| is used.
% \begin{macrocode}
%<*2ekernel|package|autoload>
\def\check@mathfonts{%
\ifx \glb@currsize \f@size
%<*trace>
\ifnum \tracingfonts>\thr@@
\@font@info{*** MATH: no change \f@size\space
curr/global (\curr@math@size/\glb@currsize)}\fi
%</trace>
\else
%<*trace>
\ifnum \tracingfonts>\thr@@
\@font@info{*** MATH: setting up \f@size\space
curr/global (\curr@math@size/\glb@currsize)}\fi
%</trace>
\glb@settings
\init@restore@glb@settings
\fi
\let\curr@math@size\f@size
\def\init@restore@glb@settings{\aftergroup\restglb@settings}%
}
% \end{macrocode}
% \end{macro}
%
%
%
%
% \begin{macro}{\init@restore@glb@settings}
% \changes{v3.0i}{1996/07/26}{macro added replacing \cs{if@inmath} switch}
% This macros does by default nothing but get redefined inside
% |\check@mathfonts| to initiate fontsize restoring in nested
% formulas.
% \begin{macrocode}
%<-trace>\let\init@restore@glb@settings\relax
%<*trace>
\def\init@restore@glb@settings{%
\ifnum \tracingfonts>\thr@@
\@font@info{*** MATH: no resetting (not in
nested math)}\fi
}
%</trace>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\restglb@settings}
% \changes{v2.3a}{1994/01/17}{New math font setup}
% \changes{v2.3c}{1994/01/26}{Correct trace info placement}
% This macro will be executed the first time after the current
% formula.
% \begin{macrocode}
\def\restglb@settings{%
%<*trace>
\ifnum \tracingfonts>\thr@@
\@font@info{*** MATH: restoring}\fi
%</trace>
\begingroup
\let\f@size\curr@math@size
\ifx\glb@currsize \f@size
%<*trace>
\ifnum \tracingfonts>\thr@@
\@font@info{*** MATH: ... already okay (\f@size)}\fi
%</trace>
\else
%<*trace>
\ifnum \tracingfonts>\thr@@
\@font@info{*** MATH: ... to \f@size}\fi
%</trace>
\glb@settings
\fi
\endgroup
}
% \end{macrocode}
% \end{macro}
%
%
% \subsubsection{Other code for math}
%
%
% \begin{macro}{\use@mathgroup}
% \changes{v1.2b}{1990/01/21}{Macro added to allow cleaner interface.}
% \changes{v1.2h}{1990/03/30}{Third argument removed (see
% \cs{math@egroup}).}
% The |\use@mathgroup| macro should be used in user
% macros to select a math group. Depending on whether or not the
% \texttt{margid} option is in force it has two or three arguments.
% For this reason it should be called as the last macro.
%
% First we test if we are inside math mode since we don't want to
% apply a useless definition.
% \changes{v1.1a}{1989/12/16}{Usage of `\quotechar=' macro added.}
% \changes{v1.1a}{1989/12/16}{Redefinition of alphabet now simpler.}
% \begin{macrocode}
\def\use@mathgroup#1#2{\relax\ifmmode
% \end{macrocode}
% \changes{v1.0o}{1990/06/24}{Tracing code added.}
% \changes{v1.0q}{1990/07/07}{Group number added to tracing.}
% \begin{macrocode}
%<*trace>
\ifnum \tracingfonts>\tw@
\count@#2\relax
\@font@info{Using \noexpand\mathgroup
(\the\count@) #2}\fi
%</trace>
% \end{macrocode}
% If so we first call the `=' macro (i.e.\ argument three) to set
% up special things for the selected math group. Then we call
% |\mathgroup| to select the group given by argument two and
% finally we place |#1| (i.e.\ the argument of the \meta{math
% alphabet identifier} at the end. This part of the code is
% surrounded by two commands which behave like |\begingroup|
% and |\endgroup| if we want \meta{math alphabet identifier}s
% but will expand into |\@empty| if we want simply switches to
% a new math group.
% \changes{v1.0p}{1990/06/30}{Added \cs{relax} after math group number.}
% Since argument number $2$ may be a digit instead of a control
% sequence we add a |\relax|.
% Otherwise something like |\mit{1}| would switch to math group
% $11$ (and back) instead of printing an oldstyle $\mit {1}$.
% \changes{v2.0b}{1992/07/26}{}
% \begin{macrocode}
\math@bgroup
\expandafter\ifx\csname M@\f@encoding\endcsname#1\else
#1\fi
\mathgroup#2\relax
% \end{macrocode}
% Before we reinsert the swallowed token (arg.\ three) into the
% input stream, in the case that the \meta{math alphabet
% identifier} isn't called in math mode, we remove the |\fi|
% with the |\expandafter| trick. This is necessary if the
% token is actually an macro with arguments. In such a case the
% |\fi| will be misinterpreted as the first argument which
% would be disastrous.
% \changes{v1.0f}{1989/12/13}
% {\cs{expandafter} added before final \cs{fi}.}
% \begin{macrocode}
\expandafter\math@egroup\fi}%
% \end{macrocode}
% The surrounding macros equal |\begingroup| and |\endgroup|. But
% using internal names makes it possible to overwrite their meaning
% in certain cases. This is for example used in \AmSTeX{} macros
% for placing accents.
% \end{macro}
%
% \begin{macro}{\math@egroup}
% \changes{v1.0q}{1990/07/07}{Tracing code added.} If the
% \texttt{margid} option is in force (which can be tested by
% looking at the definition of |\math@bgroup| we change the
% |\math@egroup| command a bit to display the current \meta{math
% group number} after it closes the scope of \meta{math alphabet}
% with |\endgroup|.
% \changes{v3.0h}{1996/05/08}{Use \cs{bgroup} instead of \cs{begingroup}
% to match a kernel change made in 1994!!!!}
% \begin{macrocode}
%<*trace>
\ifx\math@bgroup\bgroup
\def\math@egroup#1{#1\egroup
\ifnum \tracingfonts>\tw@
\@font@info{Restoring \noexpand\mathgroup
(\ifnum\mathgroup=\m@ne default\else \the\mathgroup \fi)%
}\fi}
\fi
%</trace>
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\getanddefine@fonts}
% \changes{v1.0o}{1990/06/24}{\cs{Macro} moved from fam.dtx.}
% |\getanddefine@fonts| has two arguments: the \meta{math
% group number} and the {\em family/series/shape\/} name as a
% control sequence.
% \begin{macrocode}
\def\getanddefine@fonts#1#2{%
% \end{macrocode}
% First we turn of tracing when |\tracingfonts| is less than $4$.
% \changes{v1.0o}{1990/06/24}{Adding debug code.}
% \changes{v1.0r}{1990/08/27}
% {Correcting missing name after \cs{tracingon}.}
% \begin{macrocode}
%<+debug> \pushtracing
%<+debug> \ifnum\tracingfonts<4 \tracingoff
%<+debug> \else \tracingon\getanddefine@fonts \fi
% \end{macrocode}
% \changes{v1.0o}{1990/06/24}{\cs{Adding} tracing code.}
% \changes{v1.0q}{1990/07/07}{Group number added to tracing.}
% \changes{v2.1a}{1992/09/22}{Introduced \cs{tf@size} for math size.}
% \begin{macrocode}
%<*trace>
\ifnum \tracingfonts>\tw@
\count@#1\relax
\@font@info{\noexpand\mathgroup (\the\count@) #1 :=\MessageBreak
\string#2 \tf@size/\sf@size/\ssf@size}\fi
%</trace>
% \end{macrocode}
% We append the current |\tf@size| to |#2| to obtain the font
% name.\footnote{One might ask why this expansion does not generate
% a macro name that starts with an additional \texttt{\bslash}
% character. The solution is that \texttt{\bslash escapechar} is
% set to $-1$ before \texttt{\bslash getanddefine@fonts} is
% called.} Again, |font@name| is defined globally, for the reasons
% explained in the description of |\wrong@fontshape|.
% \begin{macrocode}
\xdef\font@name{\csname \string#2/\tf@size\endcsname}%
% \end{macrocode}
% Then we call |\pickup@font| to load it if necessary.
% We remember the internal name as |\textfont@name|.
% \begin{macrocode}
\pickup@font \let\textfont@name\font@name
% \end{macrocode}
% Same game for |\scriptfont| and |\scriptscriptfont|:
% \begin{macrocode}
\xdef\font@name{\csname \string#2/\sf@size\endcsname}%
\pickup@font \let\scriptfont@name\font@name
\xdef\font@name{\csname \string#2/\ssf@size\endcsname}%
\pickup@font
% \end{macrocode}
% Then we append the new |\textfont|\ldots{} assignments to
% the |\math@fonts|.
% \begin{macrocode}
\edef\math@fonts{\math@fonts
\textfont#1\textfont@name
\scriptfont#1\scriptfont@name
\scriptscriptfont#1\font@name}%
% \end{macrocode}
% Just before ending this macro we have to pop the tracing stack
% if it was pushed before.
% \begin{macrocode}
%<+debug> \poptracing
}
%</2ekernel|package|autoload>
% \end{macrocode}
% \end{macro}
%
%
% \section{Scaled font extraction}
%
% \begin{macro}{\ifnot@nil}
% We begin with a simple auxiliary macro. It checks
% whether its argument is the token |\@nil|. If so,
% it expands to |\@gobble| which discards the following
% argument, otherwise it expands to |\@firstofone| which
% reproduces it argument.
% \changes{v2.3n}{1995/05/08}{Use \cs{@firstofone}}
% \begin{macrocode}
%<*2ekernel|autoload>
\def\ifnot@nil#1{\def\reserved@a{#1}%
\ifx\reserved@a\@nnil \expandafter\@gobble
\else \expandafter\@firstofone\fi}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\remove@to@nnil}
% \begin{macro}{\remove@angles}
% \begin{macro}{\remove@star}
% Three other auxiliary macros will be needed in the following:
% |\remove@to@nnil| gobbles up everything up to, and including,
% the next |\@nnil| token, and |\remove@angles| and |\remove@star|
% do the same
% for the character |>| and |*|, respectively, instead of |\@nnil|.
% \begin{macrocode}
\def\remove@to@nnil#1\@nnil{}
\def\remove@angles#1>{\set@simple@size@args}
\def\remove@star#1*{#1}
%</2ekernel|autoload>
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \changes{v3.0c}{1995/08/24}{Macro \cs{gobble@font@spec} removed}
%
% \begin{macro}{\extract@sizefn}
% This macro takes a size specification and parses it into size
% function and the optional and mandatory arguments.
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\extract@sizefn#1*#2\@nil{%
\if>#2>\set@size@funct@args#1\@nil
\let\sizefn@info\@empty
\else\expandafter\set@size@funct@args\remove@star#2\@nil
\def\sizefn@info{#1}\fi
}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\try@simple@size}
% This function tries to extract the given size (specified by
% |\f@size|) for the requested font shape. The font information
% must already be present in |\font@info|.
% The central macro that does the real work is |\extract@fontinfo|.
% We will first give a simple example how this macro works, and
% describe it in full generality later.
%
% Assume that the requested parameters are: {\em encoding scheme\/}
% `OT1', {\em family\/} `cm', {\em series\/} `sansserif',
% {\em shape\/} `normal', and {\em size\/} `$12$'.
% The correspondign font definitions have already been
% extracted from the macro |\OT1/cm/sansserif/normal| and
% stored in |font@info|.
% (Otherwise |\extract@fontinfo| doesn't get called.)
% This information consists of a token list made of characters
% of category code $12$ of the form
% \begin{verbatim}
% <10*>cmss10<12*>cmss12<17*>cmss17
%\end{verbatim}
% For reasonable packages one usually needs more sizes but this is
% sufficient to get the flavour.
% We will define a macro |\extract@fontinfo| to find
% the external font name (`cmss12') for us:
% \begin{verbatim}
% \def\extract@fontinfo#1<12*#2>#3<#4\@nnil{%
% \set@simple@size@args#3<#4\@nnil
% \execute@size@function{#2}}
%\end{verbatim}
% so that when it gets called via
% \begin{verbatim}
% \extract@fontinfo<10*>cmss10<12*>cmss12<17*>cmss17\@nnil
%\end{verbatim}
% |#1| will contain all characters before |<12*>|,
% |#2| will be empty, |#3| will be exactly |cmss12|,
% and |#3| will be |17>cmss17|.
% The expansion is therefore
% \begin{verbatim}
% \set@simple@size@args cmss12<17*>cmss17\@nnil
% \execute@size@function{}
%\end{verbatim}
% This means: the default (empty) size function will be executed,
% with its optional argument argument set to empty and its mandatory
% argument set to |cmss12| by |\set@simple@size@args|.
% As we discussed earlier, the effect of the default size function
% is to load the given external font (cmss12) at the specified size
% (12)---which is exactly what was intended.
%
% But this is only part of the whole story.
% It may be that the size requested does not occur
% in the token list |\font@info|.
% And the simple definition of |\extract@fontinfo| we gave
% above does not allow to specify give more than one
% size specification in front of the external font name.
%
% Let's address these two problems separately. The first one
% is solved with the following trick:
% We define |\extract@fontinfo| as follows:
% \begin{verbatim}
% \def\extract@fontinfo#1<12*#2>#3<#4\@nnil{%
% \ifnot@nil{#3}%
% {\set@simple@size@args#3<#4\@nnil
% \execute@size@function{#2}%
% }}%
%\end{verbatim}
% How does this work?
% We call |\extract@fontinfo| via
% \begin{verbatim}
% \expandafter\extract@fontinfo\font@info<12*>\@nil<\@nnil
%\end{verbatim}
% i.e. by appending |<12*>\@nil<\@nnil|.
% If the size (`12' in this case) appears in |\font@info|
% everything works as explained above, the only difference being
% that argument |#4| of |\extract@fontinfo|
% additionally gets the tokens |<12*>\@nil<\@nnil|.
% However, if the size is not found everything up to the final
% |<12*>| is in argument |#1|,
% |#3| gets |\@nil|,
% and |#2| and |#4| are empty.
% The macro |\ifnot@nil| will discard the calls to
% |\set@simple@size@args| and |execute@size@function|, and
% hence |\font@info| will continue to be equal to |\@empty|.
% This means that no simple size specification matching the
% requested size could be found.
%
% The second problem (more than one simple size specification
% for one external font name) will be addressed in
% |\set@simple@size@args| below.
%
% The macros are hidden inside other control sequences
% so that we have to build |\extract@fontinfo| in
% several steps.
%
% So here's the actual definition of |\extract@font| in
% |\try@simple@size|.
% \begin{macrocode}
% % this could be replaced by \try@size@range making the subst slower!
\def\try@simple@size{%
% \end{macrocode}
% |\reserved@a| is made an abbreviation for the head of the
% definition of the macro |\extract@fontinfo|.
% \begin{macrocode}
\def\reserved@a{\def\extract@fontinfo####1}%
% \end{macrocode}
% Now we can define |\extract@fontinfo|. Here we handle a small
% but convenient variation: in case of the default (empty) size
% function it is allowed to omit the |*| character.
% \changes{v2.0b}{1992/07/26}{}
% \changes{v2.0c}{1992/09/19}{}
% \begin{macrocode}
\expandafter\reserved@a\expandafter<\f@size>##2<##3\@nnil{%
\ifnot@nil{##2}%
{\set@simple@size@args##2<##3\@nnil
\execute@size@function\sizefn@info
}}%
% \end{macrocode}
% \changes{v2.0b}{1992/07/26}{}
% Now we call |\extract@fontinfo|. Note the |<\@nil| \textsf{tokens}
% at the end.
% \begin{macrocode}
\expandafter\expandafter
\expandafter\extract@fontinfo\expandafter\font@info
\expandafter<\f@size>\@nil<\@nnil
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\set@simple@size@args}
% As promised above, the macro |\set@simple@size@args| will handle
% the case of several size specifications in a row.
% If another size specification follows, the very first token of
% its argument list is the character |<|.
% By starting the definition as follows,
% \begin{macrocode}
\def\set@simple@size@args#1<{%
% \end{macrocode}
% parameter |#1| is empty in this case, and contains the size
% function's arguments otherwise. We distinguish these two cases
% (Note that the character |<| cannot appear in |#1|) by calling
% |\remove@angles| for empty |#1| and |\extract@sizefn|
% otherwise. In the latter case we have to take care of the
% remaining character tokens and discard them. This is done by
% |\remove@to@nnil|. Note also the use of Kabelschacht's method.
% \begin{macrocode}
\if<#1<%
\expandafter\remove@angles
\else
\extract@sizefn#1*\@nil
\expandafter\remove@to@nnil
\fi}
% \end{macrocode}
% \end{macro}
%
%
% Now, we are through with the case of a simple size, except for
% calling the size function. This will be handled later, as it is
% the same mechanism for all types of size specification. We will
% now proceed to macors for extraction of size range specification.
%
%
%
% \begin{macro}{\extract@rangefontinfo}
% |\extract@rangefontinfo| goes through a font shape definition
% in the input until it recognizes the tokens |<\@nil->|.
% It looks for font ranges with font size functions. It's operation
% is rather simple: it discards everything up to the next size
% specification and passes this on to |\is@range| for inspection.
% The specification (parameter |#2| is inserted again, in case
% it is needed later.
% \begin{macrocode}
\def\extract@rangefontinfo#1<#2>{%
\is@range#2->\@nil#2>}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\is@range}
% |\is@range| is again a sort of dispatcher macro: if the size
% specification it is looking at is not a range specification
% it discards it and calls |\extract@rangefontinfo| to continue
% the search. Otherwise it calls |\check@range| to check the
% requested size against the specified range.
%
% From the way |\is@range| is called inside |\extract@rangefontinfo|
% we see that |#2| is the character |>| if the size specification
% found is a simple one (as it does not contain a |-| character.
% This is checked easily enough and |\extract@rangefontinfo|
% called again. Note that the extra tokens inserted after the
% |\@nil| in the call to |\is@range| appear at the beginning of
% the first argument to |\extract@rangefontinfo| and are hence
% ignored.
% \begin{macrocode}
\def\is@range#1-#2\@nil{%
\if>#2\expandafter\check@single\else
\expandafter\check@range\fi}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\check@range}
% |\check@range| takes lower bound as parameter |#1|, upper bound
% as |#2|, size function as |#3| and the size function's arguments
% as |#4|. If |#3| is the special token |\@nil| |\font@info| is
% exhausted and we can stop searching.
% \begin{macrocode}
\def\check@range#1-#2>#3<#4\@nnil{%
\ifnot@nil{#3}{%
% \end{macrocode}
% If |#3| wasn't |\@nil| we have a range. We start by assuming that
% we have to recurse. Note that we have to reinsert an |<| as it
% was already removed by scanning.
% \begin{macrocode}
\def\reserved@f{\extract@rangefontinfo<#4\@nnil}%
% \end{macrocode}
% We have to make sure that both boundaries are present, if not we
% have to set them. Here we check the upper bound. If |\upper@bound|
% is zero after the assignment we set it to |\maxdimen| (upper open
% range). We need to use a \meta{dimen} register for the scan since
% we may have a decimal number as the boundary.
% \begin{macrocode}
\upper@bound0#2\p@
\ifdim\upper@bound=\z@ \upper@bound\maxdimen\fi
% \end{macrocode}
% Now we check the upper boundary against |\f@size|.
% If it is larger or equal than |\f@size| this
% range is no good and we have to recurse.
% \begin{macrocode}
\ifdim \f@size \p@<\upper@bound
% \end{macrocode}
% Otherwise we have to check the lower bound. This time it is not
% necessary to scan the boundary value into a register because if
% it is empty we get zero as desired. We could even omit the |0|
% which would result in |1pt| as default lower boundary. If
% |\f@size| is smaller than the boundary we have to recurse.
% \begin{macrocode}
\lower@bound0#1\p@
\ifdim \f@size \p@<\lower@bound
\else
% \end{macrocode}
% If both tests are passed we can try executing the size function.
% \begin{macrocode}
\set@simple@size@args#3<#4\@nnil
\execute@size@function\sizefn@info
% \end{macrocode}
% If the function was successful it should have left an external
% font name in |\external@font|. We use this to see if we can stop
% scanning. Otherwise we recurse.
% \begin{macrocode}
\ifx\external@font\@empty
\else
\let\reserved@f\@empty
\fi
\fi
\fi
\reserved@f}}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\lower@bound}
% \begin{macro}{\upper@bound}
% We use two dimen registers |\lower@bound| and |\upper@bound|
% to store the lower and upper endpoints of the range we found.
% \begin{macrocode}
%<*2ekernel|autoload>
\newdimen\lower@bound
\newdimen\upper@bound
%</2ekernel|autoload>
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\check@single}
% |\check@single| takes the size as parameter |#1|, size function
% as |#2| and the size function's arguments as |#3|. We can assume
% that there is always something in the pipeline since the very
% last entry is a faked range (see above).
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\check@single#1>#2<#3\@nnil{%
% \end{macrocode}
% We start by assuming that
% we have to recurse. Note that we have to reinsert an |<| as it
% was already removed by scanning.
% \begin{macrocode}
\def\reserved@f{\extract@rangefontinfo<#3\@nnil}%
% \end{macrocode}
% Now we check the the size against |\f@size|. If it is not equal
% |\f@size| it is no good and we have to recurse.
% \begin{macrocode}
\ifdim \f@size \p@=#1\p@
% \end{macrocode}
% Otherwise if this test is passed we can try executing the size
% function.
% \begin{macrocode}
\set@simple@size@args#2<#3\@nnil
\execute@size@function\sizefn@info
% \end{macrocode}
% If the function was successful it should have left an external
% font name in |\external@font|. We use this to see if we can stop
% scanning. Otherwise we recurse.
% \begin{macrocode}
\ifx\external@font\@empty
\else
\let\reserved@f\@empty
\fi
\fi
\reserved@f}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\set@size@funct@args}
% \begin{macro}{\set@size@funct@args@}
% This macro sets the optional and mandatory arguments for a size
% function. If the optional argument is not present it is set to
% the empty token list. The mandatory argument is delimited by the
% token |\@nil|.
% \begin{macrocode}
\def\set@size@funct@args{\@ifnextchar[%
\set@size@funct@args@{\set@size@funct@args@[]}}
% \end{macrocode}
%
% \begin{macrocode}
\def\set@size@funct@args@[#1]#2\@nil{%
\def\mandatory@arg{#2}%
\def\optional@arg{#1}}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\DeclareSizeFunction}
% This function defines a new size function hiding the internal
% from the designer. The body of the size function may use
% |\optional@arg| and |\mandatory@arg| denoting the optional and
% mandatory argument that may follow the size specification |<...>|.
% \changes{v2.1c}{1993/03/18}{Added all args to avoid blanks problems}
% \begin{macrocode}
%<*2ekernel|autoload>
\def\DeclareSizeFunction#1#2{\@namedef{s@fct@#1}{#2}}
\@onlypreamble\DeclareSizeFunction
%</2ekernel|autoload>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\execute@size@function}
% This macro is very simple. The only point worth noting
% is that calling an undefined size function will do nothing
% (actually execute a |\relax|).
% \begin{macrocode}
%<*2ekernel|package|autoload>
\def\execute@size@function#1{% %%% could be added to autoload as well
%<*trace>
\@ifundefined{s@fct@#1}%
{\errmessage{Undefined font size function #1}%
\s@fct@}%
{\csname s@fct@#1\endcsname}%
%</trace>
%<-trace> \csname s@fct@#1\endcsname
}
%</2ekernel|package|autoload>
% \end{macrocode}
% \end{macro}
%
% \changes{v2.3j}{1994/05/23}{Removed def of \cs{f@warn@break}}
%
%
% \begin{macro}{\try@size@range}
% This macro tries to find a suitable range for requested size
% (specified by |\f@size|) in |\font@info|. All the relevant
% action is done in |\extract@rangefontinfo|. All that needs
% to be done is to stuff in the token list in |\font@info| so
% that |\extract@rangefontinfo| can inspect it.
% Note the |<-*\@nil><| token at the end to stop scanning.
% \changes{v2.0b}{1992/07/26}{}
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\try@size@range{%
\expandafter\extract@rangefontinfo\font@info <-*>\@nil<\@nnil
}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\try@size@substitution}
% \changes{v2.3k}{1994/11/06}{New implementation}
% This is the last thing that can be tried. If the desired |\f@size|
% is found neither among the simple size specifications nor in one
% of the ranges the whole list of size specifications is searched for
% a nearby simple size.
% \begin{macrocode}
%<*2ekernel|def1>
\gdef\try@size@substitution{%
% \end{macrocode}
% First we do some initializations. |\@tempdimb|
% will hold the difference between the wanted size and the best
% solution found so far, so we initialise it with |\maxdimen|.
% The macro |\best@size| will hold the best size found, nothing
% found is indicated by the empty value.
% \begin{macrocode}
\@tempdimb \maxdimen
\let \best@size \@empty
% \end{macrocode}
% Now we loop over the specification
% \begin{macrocode}
\expandafter \try@simples \font@info <\number\@M>\@nil<\@nnil
}
%</2ekernel|def1>
%<*autoload>
\def\try@size@substitution{\try@simples\try@size@substitution}
%</autoload>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\font@submax}
% \changes{v2.3d}{1994/04/18}{Changed dimen to macro}
% \begin{macro}{\fontsubfuzz}
% \changes{v2.3d}{1994/04/18}{Changed dimen to macro}
% The macro |\font@submax| records the maximal deviation from the
% desired size encountered so far. Its value is used in a warning
% message at |\end{coument}|. The macro
% |\fontsubfuzz| contains the amount that will not cause terminal
% warnings (warnings still go into the transcript file).
% \begin{macrocode}
%<*2ekernel|autoload>
\def\font@submax{0pt}
\def\fontsubfuzz{.4pt}
%</2ekernel|autoload>
%<+package>\def\fontsubfuzz{0pt}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\try@simples}
% \changes{v2.3k}{1994/11/06}{New implementation}
% |\try@simples| goes through a font shape definition
% in the input until it recognizes the tokens |<*\@nil><|.
% It looks for simple sizes to determine the two closest sizes.
% It is assumed that simple sizes are in increasing order.
% \begin{macrocode}
%<*2ekernel|def1>
\gdef\try@simples#1<#2>{%
\tryif@simple#2->\tryif@simple}
%</2ekernel|def1>
%<*autoload>
\def\try@simples{\@autoload{fss1}}
%</autoload>
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\tryis@simple}
% \changes{v2.3k}{1994/11/06}{New implementation}
% |\tryis@simple| is similar to |\is@range|. If it sees a simple size,
% it checks it against the value of |\f@size| and sets
% |\lower@font@size| or |\higher@font@size|. In the latter case, it
% stops the iteration. By adding |<\number\@M>| at the end of the
% line we always have an end point. This is a hack which probably
% should be corrected.
%
% First it checks whether it is finished already, then whether the
% size specification in question is a simple one.
% \begin{macrocode}
%<*2ekernel|def1>
\gdef\tryif@simple#1-#2\tryif@simple{%
% \end{macrocode}
% Most common case for |\reserved@f| first:
% \begin{macrocode}
\let \reserved@f \try@simples
\if>#2%
% \end{macrocode}
% If so, it compares it to the value of |\f@size|. This is done using
% a dimen register since there may be fractional numbers.
% \begin{macrocode}
\dimen@ #1\p@
\ifdim \dimen@<\@M\p@
% \end{macrocode}
% If |\dimen@| is |\@M\p@| we have reached the end of the fontspec
% (hopefully) otherwise we compare the value with |\f@size| and
% compute in |\@tempdimc| the absolute value of the difference
% between the two values.
% \begin{macrocode}
\ifdim \f@size\p@<\dimen@
\@tempdimc \dimen@
\advance\@tempdimc -\f@size\p@
\else
\@tempdimc \f@size\p@
\advance\@tempdimc -\dimen@
\fi
% \end{macrocode}
% The result is then compared with the smallest difference we have
% encountered, if the new value (in |\@tempdimc| is smaller) we
% have found a size which is a better approximation so we make it
% the |\best@size| and adjust |\@tempdimb|.
% \begin{macrocode}
\ifdim \@tempdimc<\@tempdimb
\@tempdimb \@tempdimc
\def \best@size{#1}%
\fi
% \end{macrocode}
% When we have reached the end of the fontspec we substitute the
% best size found (if any). We code this inline to save macro
% space; in the past this was done by a macro called |\subst@size|.
% \begin{macrocode}
\else
% \end{macrocode}
%
%
% \begin{macro}{\subst@size}
% This macro substitutes the size recorded in |\best@size| for
% the unavailable size |\f@size|. |\font@submax| records the maximum
% difference between desired size and selected size in the
% whole run.
% \changes{v2.3d}{1994/04/18}{\cs{font@submax} and \cs{fontsubfuzz}
% now macros}
% \begin{macrocode}
% %\subst@size %% coded inline
% %\def\subst@size{%
\ifx \external@font\@empty
\ifx \best@size\@empty
\else
\ifdim \@tempdimb>\font@submax \relax
\xdef \font@submax {\the\@tempdimb}%
\fi
\let \f@user@size \f@size
\let \f@size \best@size
\ifdim \@tempdimb>\fontsubfuzz\relax
\@font@warning{Font\space shape\space
`\curr@fontshape'\space in\space size\space
<\f@user@size>\space not\space available\MessageBreak
size\space <\f@size>\space substituted}%
\fi
\try@simple@size
\do@subst@correction
\fi
\fi
% %}
% \end{macrocode}
% \end{macro}
%
% This brings us back into the main part of |\tryif@simple|.
% Finally we get rid of any rubbish left over on the input stack.
%
% \changes{v3.0c}{1995/08/24}{}
% \begin{macrocode}
\let \reserved@f \remove@to@nnil
\fi
\fi
% \end{macrocode}
% If it's a range iterate also.
% \begin{macrocode}
\reserved@f}
%</2ekernel|def1>
% \end{macrocode}
% \end{macro}
%
%
%
% \subsection{Sizefunctions}
%
% In the following we define some useful size functions.
%
%
% \begin{macro}{\s@fct@}
% This is the default size function. Mandatory argument is an
% external font name, optinal argument a scale factor.
% The font is scaled
% to |\f@size| if no optional argument is present, and to
% |\f@size| multiplied by the optional argument otherwise.
% \changes{v2.0b}{1992/07/26}{}
% \begin{macrocode}
%<*2ekernel|autoload>
\DeclareSizeFunction{}{\empty@sfcnt\@font@warning}
\DeclareSizeFunction{s}{\empty@sfcnt\@font@info}
%</2ekernel|autoload>
% \end{macrocode}
%
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\empty@sfcnt#1{%
\@tempdimb \f@size\p@
\ifx\optional@arg\@empty
\else
\@tempdimb \optional@arg\@tempdimb
#1{Font\space shape\space `\curr@fontshape'\space
will\space be\MessageBreak
scaled\space to\space size\space \the\@tempdimb}%
\fi
\edef\external@font{\mandatory@arg\space at\the\@tempdimb}}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\s@fct@gen}
% \begin{macro}{\s@fct@sgen}
% This size function generates the external name from the mandatory
% argument and the requested user size, and thus can be used for
% external names where the size is encoded in the font name. The
% optinal argument a scale factor. The font is scaled to |\f@size|
% if no optional argument is present, and to |\f@size| multiplied
% by the optional argument otherwise.
% \begin{macrocode}
%<*2ekernel|autoload>
\DeclareSizeFunction{gen}{\gen@sfcnt\@font@warning}
\DeclareSizeFunction{sgen}{\gen@sfcnt\@font@info}
%</2ekernel|autoload>
% \end{macrocode}
%
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\gen@sfcnt{%
\edef\mandatory@arg{\mandatory@arg\f@size}%
\empty@sfcnt}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\s@fct@genb}
% \begin{macro}{\s@fct@sgenb}
% This size function is similar to |gen|, but for fonts where the
% size is encoded in the font name in centipoints, as in the DC
% fonts version 1.2. The font is scaled to |\f@size|
% if no optional argument is present, and to |\f@size| multiplied
% by the optional argument otherwise.
% \begin{macrocode}
%<*2ekernel|autoload>
\DeclareSizeFunction{genb}{\genb@sfcnt\@font@warning}
\DeclareSizeFunction{sgenb}{\genb@sfcnt\@font@info}
%</2ekernel|autoload>
% \end{macrocode}
%
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\genb@sfcnt{%
\edef\mandatory@arg{\mandatory@arg\expandafter\genb@x\f@size..\@@}%
\empty@sfcnt}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\genb@x}
% \begin{macro}{\genb@y}
% The auxiliary macros |\genb@x| and |\genb@y| are used to convert
% the |\f@size| into centipoints.
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\genb@x#1.#2.#3\@@{\two@digits{#1}\genb@y#200\@@}
\def\genb@y#1#2#3\@@{#1#2}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\s@fct@sub}
% This size function handles font substitution.
% The mandatory argument is a family/series/shape combination,
% the optional argument (if present) is ignored. The font encoding
% scheme cannot be changed. Therefore, the first thing we do is to
% prepend the encoding scheme.
% \changes{v2.0b}{1992/07/26}{}
% \begin{macrocode}
%<*2ekernel|autoload>
\DeclareSizeFunction{sub}{\sub@sfcnt\@font@warning}
\DeclareSizeFunction{ssub}{\sub@sfcnt\@font@info}
%</2ekernel|autoload>
% \end{macrocode}
%
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\sub@sfcnt#1{%
\edef\mandatory@arg{\f@encoding/\mandatory@arg}%
% \end{macrocode}
% Next action is split the arg into its individual components and
% allow for a late font shape load.
% \begin{macrocode}
\begingroup
\expandafter\split@name\mandatory@arg/\@nil
\try@load@fontshape
\endgroup
% \end{macrocode}
% Then we record the current |\f@size| since it may get clobbered.
% \begin{macrocode}
\let\f@user@size\f@size
% \end{macrocode}
% Then we check whether this new combination is defined and
% give an error message if not. In this case we also switch to
% |\error@fontshape|.
% \begin{macrocode}
\expandafter
\ifx\csname\mandatory@arg\endcsname\relax
\errmessage{No\space declaration\space for\space
shape\space \mandatory@arg}%
\error@fontshape
\else
% \end{macrocode}
% Otherwise we warn the user about the substitution taking place.
% \begin{macrocode}
#1{Font\space shape\space `\curr@fontshape'\space in\space
size\space <\f@size>\space not\space available\MessageBreak
Font\space shape\space `\mandatory@arg'\space tried\space
instead}%
\expandafter\split@name\mandatory@arg/\@nil
\fi
% \end{macrocode}
% Then we restart the font specification scan by calling
% |\get@external@font|.
% \begin{macrocode}
\edef\f@size{\f@user@size}%
\get@external@font
% \end{macrocode}
% Finally |\do@subst@correction| is called to get the font name
% right.
% \begin{macrocode}
\do@subst@correction
}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\s@fct@subf}
% The |subf| size function allows substitution of another font. The
% mandatory argument is the external name of the font to be
% substituted, the optional argument a size scaling factor like
% in the default size function.
% The main difference to the default size function is the warning
% message.
% \begin{macrocode}
%<*2ekernel|autoload>
\DeclareSizeFunction{subf}{\subf@sfcnt\@font@warning}
\DeclareSizeFunction{ssubf}{\subf@sfcnt\@font@info}
%</2ekernel|autoload>
% \end{macrocode}
%
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\subf@sfcnt#1{%
#1{Font\space shape\space `\curr@fontshape'\space in\space
size\space \f@size\space not\space available\MessageBreak
external\space font\space `\mandatory@arg'\space used}%
\empty@sfcnt#1%
}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\s@fct@fixed}
% The |fixed| size function is for using a font at a different size
% than requested. A warning message is printed, and the external
% font to be used is taken from the mandatory argument.
% If an optional argument is present it is used as the `at'
% size for the font. Otherwise the font is loaded at its design size.
% \begin{macrocode}
%<*2ekernel|autoload>
\DeclareSizeFunction{fixed}{\fixed@sfcnt\@font@warning}
\DeclareSizeFunction{sfixed}{\fixed@sfcnt\@font@info}
%</2ekernel|autoload>
% \end{macrocode}
%
% \begin{macrocode}
%<*2ekernel|def2|autoload>
\def\fixed@sfcnt#1{%
\ifx\optional@arg\@empty
\let\external@font\mandatory@arg
\else
\edef\external@font{\mandatory@arg\space at\optional@arg pt}%
\fi
#1{External\space font\space `\external@font'\space loaded\space
for\space size\MessageBreak
<\f@size>}%
}
%</2ekernel|def2|autoload>
% \end{macrocode}
% \end{macro}
%
% \iffalse
%<+checkmem>\CHECKMEM
% \fi
%
%
% \Finale
|
