summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/source/latex/dashrule/dashrule.dtx
blob: 809ccf7d306cf82f1a8b3748081e9e5c31f3e2e8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
% \iffalse meta-comment
%
% Copyright (C) 2004 by Scott Pakin <scott+dash@pakin.org>
% -------------------------------------------------------
%
% This file may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.3c
% of this license or (at your option) any later version.
% The latest version of this license is in:
%
%    http://www.latex-project.org/lppl.txt
%
% and version 1.3c or later is part of all distributions of LaTeX
% version 2006/05/20 or later.
%
% \fi
%
% \iffalse
%<*driver>
\ProvidesFile{dashrule.dtx}
%</driver>
%<package>\NeedsTeXFormat{LaTeX2e}[1999/12/01]
%<package>\ProvidesPackage{dashrule}
%<*package>
    [2009/08/09 v1.2 Dashed rules]
%</package>
%
%<*driver>
\documentclass{ltxdoc}
\usepackage{dashrule}
\usepackage{titlesec}
\EnableCrossrefs
\CodelineIndex
\RecordChanges
\begin{document}
  \DocInput{dashrule.dtx}
  \PrintChanges
  \PrintIndex
\end{document}
%</driver>
% \fi
%
% \CheckSum{64}
%
% \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         \~}
%
%
% \changes{v1.0}{2001/04/23}{Initial version}
%
% \GetFileInfo{dashrule.dtx}
%
% \DoNotIndex{\addtocounter,\csname,\DeclareRobustCommand,\def,\else,\empty}
% \DoNotIndex{\endcsname,\expandafter,\fi,\hbox,\hskip,\hspace,\ifodd,\ifx}
% \DoNotIndex{\let,\mbox,\newcounter,\relax,\setcounter}
%
% ^^A  Precede every section title with a dashed rule.
% \titleformat{\section}
%   {\unskip\vskip 2.3ex plus 0.2ex
%    \vbox{\noindent\hdashrule[0pt][x]{\fill}{1pt}{5pt}\rule{5pt}{1pt}}
%    \vskip 2.3ex plus 0.2ex}
%   {\normalfont\Large\bfseries\thesection}
%   {1em}
%   {\normalfont\Large\bfseries}
%
%
% \title{The \textsf{dashrule} package\thanks{This document
%   corresponds to \textsf{dashrule}~\fileversion, dated \filedate.}}
% \author{Scott Pakin \\ \texttt{scott+dash@pakin.org}}
%
% \maketitle
%
% \begin{abstract}
%   The \textsf{dashrule} package makes it easy to draw a huge variety
%   of dashed rules (i.e., lines) in \LaTeX.  \textsf{dashrule} provides
%   a command, |\hdashrule|, which is a cross between \LaTeX's |\rule|
%   and PostScript's |setdash| command.  |\hdashrule| draws horizontally
%   dashed rules using the same syntax as |\rule| but with an
%   additional, |setdash|-like parameter that specifies the pattern of
%   dash segments and the space between those segments.  Because
%   \textsf{dashrule}'s rules are constructed internally using |\rule|
%   (as opposed to, e.g., PostScript |\special|s) they are fully
%   compatible with every \LaTeX{} back-end processor.
% \end{abstract}
%
%
% \section{Usage}
%
% \DescribeMacro{\hdashrule}
% \LaTeX's |\rule| command draws a rectangular blob of ink with a given
% width, height, and distance above the baseline.  The
% \textsf{dashrule} package introduces an analogous command,
% |\hdashrule|, which draws the same blob of ink, but horizontally
% dashed.  |\hdashrule| takes five parameters, two of which are
% optional:
%
% \bigskip
% \noindent\hspace{-\leftmargini}%
% \fbox{\texttt{\string\hdashrule}
%       \oarg{raise} \oarg{leader} \marg{width} \marg{height} \marg{dash}}
% \bigskip
%
% The \meta{raise}, \meta{width}, and \meta{height} parameters have the
% same meaning as in \LaTeX's |\rule| macro: the distance to raise the
% rule above the baseline and the width and height of the rule.
%
% Because |\hdashrule| is implemented in terms of \TeX's primitive
% leader commands (|\leaders|, |\cleaders|, and |\xleaders|), the dash
% pattern must be repeated an integral number of times.  \meta{leader}
% specifies what to do with the extra whitespace (always less than the
% width of the dash pattern) that this requirement introduces.  The
% default, which corresponds to \TeX's |\leaders| command, adds space to
% both ends of the rule so the dash patterns from multiple |\hdashrule|s
% line up.  If \meta{leader} is~|c|, which corresponds to \TeX's
% |\cleaders| command, an equal amount of whitespace is added to both
% ends of the rule.  If \meta{leader} is~|x|, which corresponds to
% \TeX's |\xleaders| command, the whitespace is divided up, and the same
% amount of whitespace separates each repetition of the dash pattern.
%
% The \meta{dash} argument specifies the dash pattern and is analogous
% to the \textit{array} argument to PostScript's |setdash| function.
% That is, it is a list of space-separated \meta{dimen}s that alternate
% ``on'' and ``off'' distances.  For instance, ``|2pt 1pt|'' means a
% 2\,pt.\ rule, followed by a 1\,pt.\ gap, followed by a 2\,pt.\ rule,
% followed by a 1\,pt.\ gap, and so forth.  An odd number of
% \meta{dimen}s is no different; ``|2pt|'' alternates 2\,pt.\ rules and
% 2\,pt.\ gaps, and ``|1pt 2pt 3pt|'' repeats ``1\,pt.\ rule,
% 2\,pt.\ gap, 3\,pt.\ rule, 1\,pt.\ gap, 2\,pt.\ rule, 3\,pt.\ gap.''
% As a special case, an empty \meta{dash} argument draws a solid rule.
%
%
% \section{Examples}
%
% The following are some typical ways to use |\hdashrule|.  Each example
% changes from the previous in only one parameter.  For clarity,
% underlines are used to indicate modified text, and the rule is
% bracketed by an upper- and lowercase~``X''.
%
% \begin{center}
% \renewcommand{\arraystretch}{1.5}
% \newcommand{\chg}[1]{\underbar{\texttt{#1}}}
% \begin{tabular}{l@{\qquad}l}
%   |\rule{2cm}{1pt}| &
%   X\rule{2cm}{1pt}x \\
%
%   |\|\chg{hdashrule}|{2cm}{1pt}|\chg{\char`\{\char`\}} &
%   X\hdashrule{2cm}{1pt}{}x \\
%
%   |\hdashrule{2cm}{1pt}{|\chg{1pt}|}| &
%   X\hdashrule{2cm}{1pt}{1pt}x \\
%
%   |\hdashrule{|\chg{4cm}|}{1pt}{1pt}| &
%   X\hdashrule{4cm}{1pt}{1pt}x \\
%
%   |\hdashrule|\chg{[0.5ex]}|{4cm}{1pt}{1pt}| &
%   X\hdashrule[0.5ex]{4cm}{1pt}{1pt}x \\
%
%   |\hdashrule[0.5ex]{4cm}{1pt}{|\chg{3mm}|}| &
%   X\hdashrule[0.5ex]{4cm}{1pt}{3mm}x \\
%
%   |\hdashrule[0.5ex]{4cm}{|\chg{1mm}|}{3mm}| &
%   X\hdashrule[0.5ex]{4cm}{1mm}{3mm}x \\
%
%   |\hdashrule[0.5ex]{4cm}{1mm}{3mm |\chg{3pt}|}| &
%   X\hdashrule[0.5ex]{4cm}{1mm}{3mm 3pt}x \\
%
%   |\hdashrule[0.5ex]{4cm}{1mm}{%| \\[-1.5ex]
%   |  3mm 3pt |\chg{1mm 2pt}|}| &
%   X\hdashrule[0.5ex]{4cm}{1mm}{3mm 3pt 1mm 2pt}x \\
% \end{tabular}
% \end{center}
%
% \bigskip
% \noindent
% These next examples show the effect of using different leader types.
% Each leader is used with both a 4\,cm~wide rule and a 3\,cm~wide rule.
%
% \begin{center}
% \renewcommand{\arraystretch}{1.25}
% \newcommand{\chg}[1]{\underbar{\texttt{#1}}}
% \begin{tabular}{l@{\qquad}l}
%   |\hdashrule[0.5ex]{4cm}{1mm}{8mm 2pt}| &
%   X\hdashrule[0.5ex]{4cm}{1mm}{8mm 2pt}x \\
%
%   |\hdashrule[0.5ex]{3cm}{1mm}{8mm 2pt}| &
%   X\hdashrule[0.5ex]{3cm}{1mm}{8mm 2pt}x \\[2ex]
%
%   |\hdashrule[0.5ex]|\chg{[c]}|{4cm}{1mm}{8mm 2pt}| &
%   X\hdashrule[0.5ex][c]{4cm}{1mm}{8mm 2pt}x \\
%
%   |\hdashrule[0.5ex]|\chg{[c]}|{3cm}{1mm}{8mm 2pt}| &
%   X\hdashrule[0.5ex][c]{3cm}{1mm}{8mm 2pt}x \\[2ex]
%
%   |\hdashrule[0.5ex][|\chg{x}|]{4cm}{1mm}{8mm 2pt}| &
%   X\hdashrule[0.5ex][x]{4cm}{1mm}{8mm 2pt}x \\
%
%   |\hdashrule[0.5ex][|\chg{x}|]{3cm}{1mm}{8mm 2pt}| &
%   X\hdashrule[0.5ex][x]{3cm}{1mm}{8mm 2pt}x \\
% \end{tabular}
% \end{center}
%
% \noindent
% Notice how the dashes in the first pair of |\hdashrule|s line up; the
% rules in the second pair each have an equal amount of whitespace on
% either side of the rule; and the rules in the third pair have extra
% spaces within the dash pattern itself instead of around it.  The
% |x|~qualifier is rarely useful for dashed rules because it alters the
% pattern itself.  However, |x| does enable rules with long dashes to
% better fill a comparatively small width, as in the following example:
%
% \begin{center}
% \renewcommand{\arraystretch}{1.25}
% \begin{tabular}{l@{\qquad}l}
%   |\hdashrule[0.5ex][x]{3in}{2pt}{2cm 0pt}| \\
%   X\hdashrule[0.5ex][x]{3in}{2pt}{2cm 0pt}x
% \end{tabular}
% \end{center}
%
% \noindent
% The gaps in the above are clearly wider than~|0pt|, but they \emph{are}
% evenly spaced.
%
%
% \section{Differences from \texttt{setdash}}
%
% |\hdashrule| is different from PostScript's |setdash| command in the
% following ways:
%
% \begin{itemize}
%   \item |setdash| takes on/off values in terms of PostScript points
%   (\TeX{} ``big points'' or~``|bp|''), while |\hdashrule| requires
%   explicit units.
%
%   \item There is no equivalent of |setdash|'s \textit{offset}
%   parameter to specify a starting offset into the pattern.  If you're
%   desperate you can fake \textit{offset} with a leading |\rule| and
%   |\hspace|.
% \end{itemize}
%
%
% \StopEventually{^^A
%   \section{Future Work}
%
%   \textsf{dashrule} \fileversion{} supports only horizontally dashed
%   rules.  Future versions (if any) may support vertically dashed rules
%   as well.  For the time being, the \textsf{graphicx} package's
%   \texttt{\string\rotatebox} can be used to define a
%   \texttt{\string\vdashrule} in terms of a rotated
%   \texttt{\string\hdashrule}.
%
%   The next logical step after adding a \texttt{\string\vdashrule} is
%   to support dashed rectangles, which would be composed of
%   \texttt{\string\hdashrule}s and \texttt{\string\vdashrule}s.  Other
%   possible enhancements would be a way of drawing dotted lines,
%   presumably composed from the limited set of circle characters
%   available in \LaTeX's fonts.
% }
%
%
% \section{Implementation}
%
%    \begin{macrocode}
%<*package>
%    \end{macrocode}
%
% We load the \textsf{ifmtarg} package to help check if the final
% argument to |\hdashrule| is empty.
%    \begin{macrocode}
\RequirePackage{ifmtarg}
%    \end{macrocode}
%
% \begin{macro}{\hdr@do@rule}
% This macro is exactly like \LaTeX's |\rule| except that the optional
% argument is required, and it has the side effect of pointing
% |\hdr@do@something| to |\hdr@do@skip|.
%    \begin{macrocode}
\def\hdr@do@rule[#1]#2#3{%
  \rule[#1]{#2}{#3}%
  \let\hdr@do@something=\hdr@do@skip
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\hdr@do@skip}
% This macro takes the same arguments as |\hdr@do@rule|, but instead of
% drawing a rule, it inserts an equivalent amount of horizontal
% whitespace.  Additionally, it points |\hdr@do@something| to
% |\hdr@do@rule| as a side effect.
%    \begin{macrocode}
\def\hdr@do@skip[#1]#2#3{%
  \hspace*{#2}%
  \let\hdr@do@something=\hdr@do@rule
}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\c@hdr@segments}
% \begin{macro}{\hdr@tally@segments}
% Dash patterns containing an odd number of segments are treated
% differently from dash patterns containing an even number of segments.
% We therefore define a macro, |\hdr@tally@segments|, which counts the
% number of space-separated segments in a dash pattern and stores the
% tally in the |hdr@segments| counter.  Note that |hdr@segments| should
% be initialized to~|0| before invoking |\hdr@tally@segments|.
%    \begin{macrocode}
\newcounter{hdr@segments}
\def\hdr@tally@segments#1 {%
  \ifx#1!%
  \else
    \addtocounter{hdr@segments}{1}%
    \expandafter\hdr@tally@segments
  \fi
}
%    \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\hdashrule}
% This is the only macro in \textsf{dashrule}'s external interface.
% (|\hdashrule@ii| does most of the work for |\hdashrule|, though.)  All
% |\hdashrule| itself does is invoke |\hdashrule@i| with its first
% optional argument or~|0.0pt| if none was provided.  |\hdashrule@i|, in
% turn, invokes |\hdashrule@ii| with the two optional arguments,
% supplying |\empty| as the default value of the second optional
% argument.
% \changes{v1.1}{2008/04/27}{Preceded the invocation of
%   \texttt{\string\string\string\@testopt} with an empty box so that
%   \texttt{\string\string\string\hdashrule} can now begin a paragraph}
%    \begin{macrocode}
\DeclareRobustCommand{\hdashrule}{\mbox{}\@testopt{\hdashrule@i}{0pt}}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\hdashrule@i}
% Supply |\empty| as the default second argument and call
% |\hdashrule@ii|.
%    \begin{macrocode}
\def\hdashrule@i[#1]{\@testopt{\hdashrule@ii[#1]}\empty}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\hdashrule@ii}
% Now we can do the real work for |\hdashrule|.  |\hdashrule@ii| takes
% the following parameters:
%
% \begin{center}
% \begin{tabular}{ccccc}
%   |#1| & |#2| & |#3| & |#4| & |#5| \\
%   \oarg{raise} & \oarg{leader} & \marg{width} & \marg{height} & \marg{dash}
% \end{tabular}
% \end{center}
%
% \noindent
% The \meta{raise}, \meta{width}, and \meta{height} parameters have the
% same meaning as in \LaTeX's |\rule| macro.  \meta{leader} specifies
% the \TeX\ leader function to use to fill \meta{width} amount of
% space.  It should be |c| for |\cleaders|, |x| for |\xleaders|, or
% nothing for ordinary |\leaders|.  The \meta{dash} argument specifies
% the dash pattern and is analogous to the \textit{array} argument to
% PostScript's |setdash| function.  That is, it is a list of
% space-separated \meta{dimen}s that alternate ``on'' and ``off''
% distances.
%    \begin{macrocode}
\def\hdashrule@ii[#1][#2]#3#4#5{%
%    \end{macrocode}
% \end{macro}
%
% If the final argument, \meta{dash}, is empty, we fall back to using an
% ordinary |\rule| command.  This is not terribly useful in practice but
% does make |\hdashrule| behave more like PostScript's |setdash|.
%    \begin{macrocode}
  \@ifmtarg{#5}{%
    \rule[#1]{#3}{#4}%
  }{%
%    \end{macrocode}
% Here begins the common case, in which the \meta{dash} argument is
% nonempty.
%
% \begin{macro}{\hdr@do@something}
% The |\hdr@do@something| alias alternates between |\hdr@do@rule|
% and |\hdr@do@skip|, starting with |\hdr@do@rule|.
%    \begin{macrocode}
    \let\hdr@do@something=\hdr@do@rule
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\hdr@parse@dash}
% For every space-separated \meta{dimen} in \meta{dash}, we invoke
% |\hdr@do@something| to draw a rule or a space, as appropriate.  We
% define |\hdr@parse@dash| within |\hdashrule@ii| so we don't have to
% pass in |\hdashrule@ii|'s~|#1| and~|#4| on every invocation.
%    \begin{macrocode}
    \def\hdr@parse@dash##1 {%
      \ifx##1!%
      \else
        \hdr@do@something[#1]{##1}{#4}%
        \expandafter\hdr@parse@dash
      \fi
    }%
%    \end{macrocode}
% We now count the number of segments in the dash pattern so we can
% determine if we have an even or odd number of them.
%    \begin{macrocode}
    \setcounter{hdr@segments}{0}%
    \hdr@tally@segments#5 !
%    \end{macrocode}
% Finally, we invoke |\leaders|, |\cleaders|, or |\xleaders| to draw the
% dashed line, repeating the pattern until \meta{width} space is filled.
% The trick here is that odd-lengthed pattern descriptions must be
% repeated to yield the complete pattern.  For instance, the pattern
% ``|1pt|'' is actually short for ``1\,pt.\ rule, 1\,pt.\ space,'' and
% ``|2pt 4pt 6pt|'' is an abridged version of ``2\,pt.\ rule, 4\,pt.\
% space, 6\,pt.\ rule, 2\,pt.\ space, 4\,pt.\ rule, 6\,pt.\ space.''
% Although it is valid to repeat even-lengthed patterns as well---an
% earlier draft of |\hdashrule@ii| did just that---this produces
% inferior results because \TeX's various leader commands do not split
% boxes.  The longer the pattern, the less likely it will fit snugly
% into the given width.
% \changes{v1.2}{2009/08/08}{Ended the rule with an empty box to enable
%   \texttt{\string\string\string\hdashrule} to work within a
%   \texttt{tabular} cell.  Thanks to Piazza Luca for the bug report}
%    \begin{macrocode}
    \ifodd\c@hdr@segments
      \csname#2leaders\endcsname
        \hbox{\hdr@parse@dash#5 #5 ! }%
        \hskip#3
    \else
      \csname#2leaders\endcsname
        \hbox{\hdr@parse@dash#5 ! }%
        \hskip#3
    \fi
    \mbox{}%
  }%
}
%    \end{macrocode}
% \end{macro}
%
% \Finale
\endinput