summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/tex/context/base/mkiv/spac-grd.mkiv
blob: 4864cd646bf0b37e4332555221260cae63a423e4 (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
%D \module
%D   [       file=spac-grd,
%D        version=2009.10.16, % 1998.03.10, was core-grd.tex
%D          title=\CONTEXT\ Spacing Macros,
%D       subtitle=Grid Snapping,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
%C
%C This module is part of the \CONTEXT\ macro||package and is
%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
%C details.

%D This module will be merged into spac-ver.mkiv.

\writestatus{loading}{ConTeXt Spacing Macros / Grid Snapping}

\unprotect

%D A rather crappy macro that we need to avoid and as such it will probably
%D disappear:

\installcorenamespace{lastnodepusher}

\let\poplastnode\relax

\unexpanded\def\pushlastnode
  {\csname\??lastnodepusher
     \ifcsname\??lastnodepusher\the\lastnodetype\endcsname
       \the\lastnodetype
     \else
       \s!unknown
     \fi
   \endcsname}

\setvalue{\??lastnodepusher\number\kernnodecode}%
  {\unexpanded\edef\poplastnode{\kern\the\lastkern\relax}%
   \kern-\lastkern}

\setvalue{\??lastnodepusher\number\gluenodecode}%
  {\unexpanded\edef\poplastnode{\vskip\the\lastskip\relax}%
   \vskip-\lastskip}

\setvalue{\??lastnodepusher\number\penaltynodecode}%
  {\unexpanded\edef\poplastnode{\penalty\the\lastpenalty\relax}%
   \nobreak}

\setvalue{\??lastnodepusher\s!unknown}%
  {\let\poplastnode\relax}

%D Moved from supp-box:

%D \macros
%D  {startbaselinecorrection,baselinecorrection,
%D   showbaselinecorrection,offbaselinecorrection}
%D
%D Spacing around ruled boxes can get pretty messed up. The
%D next macro tries as good as possible to fix this.
%D
%D \startbuffer[1]
%D \startbaselinecorrection
%D \ruledhbox{Rule Brittanica}
%D \stopbaselinecorrection
%D \stopbuffer
%D
%D \typebuffer[1]
%D
%D The macros put some white space around the box:
%D
%D \getbuffer[1]
%D
%D A simple alternative is \type {\baselinecorrection}, which
%D only looks at the previous line.
%D
%D \startbuffer[2]
%D \baselinecorrection
%D \ruledhbox{Rule Brittanica}
%D \baselinecorrection
%D \stopbuffer
%D
%D \typebuffer[2]
%D
%D This time the last preceding line gets a correction,%
%D dependant on the depth.
%D
%D \getbuffer[2]
%D
%D One can make the correction visible by saying \type
%D {\showbaselinecorrection}. Part of the correction is
%D calculated from the dimensions of a~(. One can disble the
%D correction by calling \type {\offbaselinecorrection}.
%D
%D When visualize the first example looks like:
%D
%D {\showbaselinecorrection\getbuffer[1]}
%D
%D and the second one comes out as:
%D
%D {\showbaselinecorrection\getbuffer[2]}

% \definecolor[GridLineColor][red]
% \definecolor[GridTextColor][blue]

\newdimen\d_spac_lines_correction_before
\newdimen\d_spac_lines_correction_after

\newbox  \b_spac_lines_correction_before
\newbox  \b_spac_lines_correction_after

\def\spac_lines_initialize_corrections
  {\setbox\b_spac_lines_correction_before\hbox{\setstrut\strut}%
   \setbox\b_spac_lines_correction_after \hbox{(}%
   \d_spac_lines_correction_before\dimexpr\ht\b_spac_lines_correction_before-\ht\b_spac_lines_correction_after\relax
   \d_spac_lines_correction_after \dimexpr\dp\b_spac_lines_correction_before-\dp\b_spac_lines_correction_after\relax
   \ifdim\d_spac_lines_correction_before<\zeropoint\d_spac_lines_correction_before\zeropoint\fi
   \ifdim\d_spac_lines_correction_after <\zeropoint\d_spac_lines_correction_after \zeropoint\fi}

%unexpanded\def\dotopbaselinecorrection{\kern\d_spac_lines_correction_before}
%unexpanded\def\dobotbaselinecorrection{\kern\d_spac_lines_correction_after }

% experiment, todo: proper mkiv mechanism
%
% \input ward \par
% \startframedtext test  \stopframedtext
% \input ward \par
% \startlinecorrection \framed{xxx} \stoplinecorrection
% \input ward \par
%
% \setupwhitespace[big]
%
% \input ward \par
% \startframedtext test  \stopframedtext
% \input ward \par
% \startlinecorrection \framed{xxx} \stoplinecorrection
% \input ward \par

% to be redone:

\unexpanded\def\dotopbaselinecorrection{\expandafter\blank\expandafter[\the\d_spac_lines_correction_before]}
\unexpanded\def\dobotbaselinecorrection{\expandafter\blank\expandafter[\the\d_spac_lines_correction_after ]}

\def\showbaselinecorrection
  {\def\dobaselinecorrection % visualization is not watertight!
     {\bgroup
      \ifdim\prevdepth>\zeropoint
        \kern-\prevdepth
      \fi
      \setbox\scratchbox\emptyhbox
      \wd\scratchbox\hsize
      \dp\scratchbox\strutdp
      \nointerlineskip
      \forgetall
      \ruledvpack{\box\scratchbox}%
      \egroup
      \prevdepth\strutdp}%
   \def\dotopbaselinecorrection
     {\hrule\s!height\d_spac_lines_correction_before}%
   \def\dobotbaselinecorrection
     {\hrule\s!height\d_spac_lines_correction_after}}

\def\dobaselinecorrection % beware, this one is redefined / used locally elsewhere
  {\ifdim\prevdepth>\zeropoint\kern-\prevdepth\fi
   \kern\strutdp
   \prevdepth\strutdp}

\def\baselinecorrection
  {\endgraf
   \ifvmode
     \ifdim\prevdepth<\maxdimen
       \ifdim\prevdepth<\zeropoint \else
         \ifdim\prevdepth<\strutdepth \relax
           \pushlastnode
           \dobaselinecorrection
           \poplastnode
         \fi
       \fi
     \fi
   \fi}

\def\pagebaselinecorrection
  {\ifdim\pagegoal<\maxdimen
     \ifdim\pagetotal>\lineheight % or \topskip
       \scratchdimen\pagetotal
       \advance\scratchdimen\lineheight
       \ifdim\scratchdimen<\pagegoal
         \baselinecorrection
       \fi
     \fi
   \fi}

\unexpanded\def\startbaselinecorrection
  {\bgroup
   \let\stopbaselinecorrection\egroup
   \ifcase\baselinecorrectionmode
   \or % normal
     \baselinecorrection
     \ifvmode
       \setbox\scratchbox\vbox\bgroup\ignorespaces
       \let\stopbaselinecorrection\donormalstopbaselinecorrection
     \fi
   \or % off
   \or % force
     \baselinecorrection
     \ifvmode
       \setbox\scratchbox\vbox\bgroup\ignorespaces
       \let\stopbaselinecorrection\doforcedstopbaselinecorrection
     \fi
   \fi}

\let\stopbaselinecorrection\relax

\def\donormalstopbaselinecorrection % I have to check columns yet.
  {\egroup
   \topbaselinecorrection
   \box\scratchbox
   \botbaselinecorrection
   \egroup}

\def\doforcedstopbaselinecorrection % I have to check columns yet.
  {\egroup
   \forcedtopbaselinecorrection
   \box\scratchbox
   \forcedbotbaselinecorrection
   \egroup}

%D We do a bit more checking than needed. The pageborder check
%D is not needed, but I want to look the visualization as good
%D as possible too.

\setnewconstant\baselinecorrectionmode\plusone

\def\onbaselinecorrection   {\baselinecorrectionmode\plusone  }
\def\offbaselinecorrection  {\baselinecorrectionmode\plustwo  }
\def\forcebaselinecorrection{\baselinecorrectionmode\plusthree}

%D \macros
%D  {topbaselinecorrection,botbaselinecorrection}
%D
%D The actual top and bottom corrections are implemented as:

\def\topbaselinecorrection
  {\ifvmode \ifdim\pagegoal<\maxdimen
     \forcedtopbaselinecorrection
   \fi \fi}

\def\forcedtopbaselinecorrection
  {\ifvmode
     \bgroup
     \spac_lines_initialize_corrections
     \whitespace % no longer ok
     \nointerlineskip
     \dotopbaselinecorrection
     \egroup
   \fi}

\def\botbaselinecorrection
  {\ifvmode
     \bgroup
     \spac_lines_initialize_corrections
     \dobotbaselinecorrection
     \allowbreak % new, otherwise problems when many in a row
     \prevdepth\strutdp
     \egroup
   \fi}

\let\forcedbotbaselinecorrection\botbaselinecorrection

% nointerlineskip
%
% startpacked
%     \startlinecorrection \framed{test} \stoplinecorrection
%     \startlinecorrection \framed{test} \stoplinecorrection
% \stoppacked

\def\forcedtopbaselinecorrection
  {\ifvmode
     \bgroup
     \spac_lines_initialize_corrections
     \vspacing[\v!white]
%      \nointerlineskip %
     \dotopbaselinecorrection
     \egroup
\fi}

\def\dobaselinecorrection
  {\ifdim\prevdepth>\zeropoint
     \vspacing[\the\dimexpr-\prevdepth+\strutdp\relax]%
   \else
     \vspacing[\the\dimexpr\strutdp\relax]%
   \fi
   \prevdepth\strutdp}

\let\normalstartbaselinecorrection\startbaselinecorrection

\unexpanded\def\startbaselinecorrection
  {\ifgridsnapping
     \snaptogrid[\v!normal]\vbox\bgroup
     \let\stopbaselinecorrection\egroup
   \else
     \normalstartbaselinecorrection
   \fi}

% This is new (and experimental) and might replace some of the above. beware it doesn't always work
% out well, e.g. when used grouped and such (e.g. before display math doesn't work out well).

\unexpanded\def\spac_fake_next_line_new
  {\par
   \begingroup
   \reseteverypar
   \dontleavehmode\hpack{\strut}\par
   \clf_fakenextstrutline
   \ifdim\pagetotal>\lineheight
     \pagetotal\dimexpr\pagetotal-\lineheight\relax
   \fi
   \endgroup}

\unexpanded\def\spac_fake_next_line_old
  {\par
   \begingroup
   \reseteverypar
   \dontleavehmode\hpack to \zeropoint{\page_sides_anchor\hss\strut}% just a tracer
   \vskip-\parskip
   \vskip-\struttotal
   \endgroup}

%let\fakenextstrutline\spac_fake_next_line_old
\let\fakenextstrutline\spac_fake_next_line_new

\protect \endinput