%%% ====================================================================
%%% @LaTeX-style-file{
%%% author = "Alan Jeffrey",
%%% version = "1.1",
%%% date = "02 June 1992",
%%% time = "13:39:09 BST",
%%% filename = "diagramf.sty",
%%% address = "School of Cognitive and Computing Sciences
%%% University of Sussex
%%% Brighton BN1 9QH
%%% UK",
%%% telephone = "+44 273 606755 x 3238",
%%% FAX = "+44 273 678188",
%%% checksum = "50716 222 988 7967",
%%% email = "alanje@cogs.sussex.ac.uk",
%%% codetable = "ISO/ASCII",
%%% keywords = "diagrams, metafont",
%%% supported = "yes",
%%% abstract = "This is a LaTeX style file for importing
%%% diagrams drawn in metafont.",
%%% docstring = "This is part of the diagramf package which
%%% interfaces TeX and metafont. It is
%%% described in diagramf.tex.
%%%
%%% Copyright 1992 Alan Jeffrey.
%%%
%%% The checksum field above contains a CRC-16
%%% checksum as the first value, followed by the
%%% equivalent of the standard UNIX wc (word
%%% count) utility output of lines, words, and
%%% characters. This is produced by Robert
%%% Solovay's checksum utility.",
%%% package = "diagramf",
%%% dependencies = "diagramf.mf",
%%% maintainer = "Jeremy Gibbons",
%%% address-maintainer = "Department of Computer Science
%%% University of Aukland
%%% Private Bag
%%% Aukland
%%% New Zealand",
%%% email-maintainer = "jeremy@cs.aukuni.ac.nz",
%%% }
%%% ====================================================================
%%%
%%% 25 Oct 1990, v1.0: Released version 1.0.
%%%
%%% 29 Oct 1990, v1.01: Discovered I'd put \everylabel into the
%%% diagram rather than the label. Silly me.
%%%
%%% 30 Oct 1990, v1.02: \diagramf now uses \copy to put down the
%%% diagram rather than \box, so diagrams can be reused.
%%%
%%% 2 Jun 1992, v1.1: Added standard headers.
% This style allows you to use diagrams generated in metafont with TeX
% lables, such as those produced with diagramf.mf.
%
% To use the diagrams generated by example.mf, you say
%
% \diagramfile{example}
%
% which loads all the diagrams and stores them in boxes. You can then
% use a diagram by saying (for example)
%
% \diagramf{2}
%
% which gets you the second diagram. When you load in another
% file of diagrams, you over-write the previous diagrams.
%
% All the definitions made by \diagramfile are purely local, so if you
% say
%
% \diagramfile{foo}
% {\diagramfile{baz}\diagramf{1}}
% \diagramf{2}
%
% You get diagram 1 from baz, and diagram 2 from foo.
%
% The metafont program for the diagrams contains TeX code for the
% labels, which it spits out to an auxilary .dia file, of the
% form
%
% \newdiagramfont{example}
% \newdiagram{2}
% \diagramlabel{0}{4.88908pt}{0pt}
% $g \circ h$
% \enddiagramlabel
% \diagramchar{2}
% \endnewdiagram
%
% This says that the font for these diagrams is called example, and
% it contains diagram number 2. This has one label (number 0),
% which should be positioned at coordinates (4.88909pt, 0pt), and whose
% text is $g \circ h$. The diagram itself is character 1 in the
% font.
%
% When \diagramfile{example} is called, it loads in example.dia, which
% sets the boxes containing the diagrams, and in turn writes out
% example.dim, containing the dimensions of the lables, for example
%
% wd#[2][0] := 20.3344pt#;
% ht#[2][0] := 6.94444pt#;
% dp#[2][0] := 1.94444pt#;
%
% This is then read by metafont, and we go round the production cycle
% one more time...
%
% Right, that's what we're doing, let's get on with it!
% To begin with, the counters, dimensions, etc. we need.
\newwrite\dimensionsfile % The .dim output file
\newcount\diagramnumber % The number of the diagram
\newcount\labelnumber % The number of the label
\newdimen\labelxoffset % The x-coordinate of the label
\newdimen\labelyoffset % The y-coordinate of the label
\newtoks\everylabel % Tokens put in every label (a la \everymath)
% A handy macro for hacking around with \csname's...
% \csnameafter\foo{baz} expands out to \foo\baz.
\def\csnameafter#1#2{\expandafter#1\csname#2\endcsname}
% \percent is a % mark, only with catcode 11 (i.e. a letter),
% similarly \hashmark.
{\catcode`\%=11\gdef\percent{%}}
{\catcode`\#=11\gdef\hashmark{#}}
% \allocatebox{foo} gets a new box \foo, if \foo is undefined.
\def\allocatebox#1%
{\@ifundefined{#1}{\csnameafter\newbox{#1}}{}}
% In order to do this, \newbox has to be non-\outer, grumble grumble
% why was it ever \outer in the first place grumble grumble...
\def\newbox{\alloc@4\box\chardef\insc@unt}
% When you say \diagramfile{example} we open
% example.dim for output, read in example.dia, and then close
% example.dia.
\def\diagramfile#1%
{\immediate\openout\dimensionsfile #1.dim%
\immediate\write\dimensionsfile{\percent Filename: #1.dim}%
\immediate\write\dimensionsfile{\percent Generated by: diagramf.sty}%
\immediate\write\dimensionsfile{\percent Date: \today}%
\@input{#1.dia}%
\immediate\closeout\dimensionsfile
\typeout{Dimensions written on #1.dim.}}
% The first command in FONTNAME.dia should be
% \newdiagramfont{FONTNAME}---this causes us to load the font in.
% (Exercise for the reader: why isn't this done by \diagramfile? Hint: if
% we run LaTeX before running metafont, neither FONTNAME.dia nor
% FONTNAME.tfm will exist.)
\def\newdiagramfont#1{\font\diagramfont=#1\relax}
% Then the macro that defines a diagram. \newdiagram{N} makes us
% define \diagramnumber to be N, allocate a new box \diagram-N, and
% set the box to whatever comes between here and the \endnewdiagram.
\def\newdiagram#1%
{\diagramnumber=#1
\allocatebox{diagram-#1}%
\csnameafter\setbox{diagram-#1}\hbox\bgroup}
\def\endnewdiagram
{\egroup}
% Within the \newdiagram we can have commands to set labels, of the
% form \diagramlabel{N}{X}{Y}...\enddiagramlabel. To begin with, we
% set \labelnumber to N, \labelxoffset to X, \labelyoffset to Y, then
% set box 0 to be everything up to the \enddiagramlabel.
\def\diagramlabel#1#2#3%
{\labelnumber=#1
\labelxoffset=#2
\labelyoffset=#3
\setbox0\hbox\bgroup\the\everylabel}
% When we have set the box containing the label, we write its
% dimensions on the .dim file, move the box to coordinates
% (\labelxoffset, \labelyoffset), reduce it to zero size, and set it.
\def\enddiagramlabel
{\egroup
\immediate\write\dimensionsfile
{wd\hashmark[\the\diagramnumber][\the\labelnumber]
:= \the\wd0\hashmark;}%
\immediate\write\dimensionsfile
{ht\hashmark[\the\diagramnumber][\the\labelnumber]
:= \the\ht0\hashmark;}%
\immediate\write\dimensionsfile
{dp\hashmark[\the\diagramnumber][\the\labelnumber]
:= \the\dp0\hashmark;}%
\setbox0\hbox{\kern\labelxoffset\raise\labelyoffset\box0}%
\wd0=0pt \ht0=0pt \dp0=0pt
\box0}
% The other command you can have within a diagram is \diagramchar{N}
% which just causes us to set character N of \diagramfont.
\def\diagramchar#1%
{{\diagramfont\char#1\relax}}
% Finally, to set a diagram, you just say \diagramf{N} which causes us
% to leave vertical mode (in the same fashion as \mbox) and set box
% \diagram-N.
\def\diagramf#1%
{\leavevmode
\@ifundefined
{diagram-#1}
{??\@warning{Diagram #1 on page \thepage\space undefined}}
{\csnameafter\copy{diagram-#1}}}