summaryrefslogtreecommitdiff
path: root/macros/latex/contrib/cals/cals/span.dtx
blob: c84a7bfa1ba0d5104755172dc4e4e8e5a41df850 (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
% \subsection{Spanned cells}

% The technical approach:
% \begin{itemize}
% \item Spanning is started in the left top corner using the
%    command |\nullcell{lt...}|
% \item The spanned cell is split on the table cells using the
%    command |\nullcell|. These nullcells are responsible for
%    correct decorations and for calculating the big cell dimensions.
% \item The content of the spanned cells comes in the end,
%    in the right bottom corner.
% \end{itemize}

% It is possible to have several active spans at once, therefore we
% have to remember them. I use a queue. Each time a left column
% of a span is started, we take span data from the queue. After the
% right column of the span, we put the data back to the queue,
% to the end. Probably it is not obvious at the first look (at least,
% I needed time to find this simple idea) that this rotating queue
% is always right: when spanning (its left column) starts again,
% the beginning of the queue always contains data for exactly this spanning.

% \begin{macro}{\cals@spanq@heights}
% The queue for height tracking. In the first version I also had
% a queue for decorations, but later cancelled it.
% I use |\def| instead of |\newcommand| in order that |\show|
% prints "|macro|" instead of "|\long macro|". The latter breaks
% unit tests.
%    \begin{macrocode}
\def\cals@spanq@heights{}
%    \end{macrocode}
% \end{macro}

% \begin{macro}{\cals@span@get}
% Gets |\cals@span@height| from the queue.
%    \begin{macrocode}
\newcommand\cals@span@get{%
\llt@decons\cals@spanq@heights \cals@span@height=\llt@car\relax}
%    \end{macrocode}
% \end{macro}

% \begin{macro}{\cals@span@put}
% Puts |\cals@span@height| to the queue.
%    \begin{macrocode}
\newcommand\cals@span@put{%
\edef\cals@tmp{\the\cals@span@height}\llt@snoc\cals@spanq@heights\cals@tmp}
%    \end{macrocode}
% \end{macro}

% \begin{macro}{\nullcell}
% The big spanned cell is split on the table cells, which are
% identified by |\nullcell|s. The task is to produce correct
% decorations and to track the parameters of the spanned cell.
% \begin{itemize}
% \item Decorations: if defined, the background color is always
% added to the column separation row.
% \item Decorations: the borders are set to 0pt (disabled),
% except for the borders which are requested by
% the parameter of |\nullcell|: |l| for the left border,
% |t| for the top, |r| for the right, |b| for the bottom.
% \item More precisely, the letters in the argument are not to
% specify which decorations to use, but to specify the location
% of the small cell in the big cell. The use for decorations
% is just an useful side-effect.
% \item Action |l|: take the span data from the queue.
% \item Action |r|: update the height of the current span,
% put the data to the queue.
% \item Action |b|: do not put an empty box to the current row.
% Instead, accumulate the width of the current span.
% (Preparation for |\spancontent|.)
% \end{itemize}
%    \begin{macrocode}
\newcommand\nullcell[1]{%
%    \end{macrocode}
% First of all, parse the argument and set the if-commands |\cals@span@ifX|.
% Then get the width of the cell.
%    \begin{macrocode}
\let\cals@span@ifL=\cals@iffalse
\let\cals@span@ifT=\cals@iffalse
\let\cals@span@ifR=\cals@iffalse
\let\cals@span@ifB=\cals@iffalse
\def\next##1{\ifx\relax##1\let\next=\relax \else
 \expandafter\let\csname cals@span@if##1\endcsname=\cals@iftrue \fi
 \next}%
\uppercase{\next #1}\relax
\llt@rot\cals@colwidths \let\cals@nullcell@width=\llt@car
%    \end{macrocode}
% Action "l": update the height, supress the borders, set the rowspan markers.
%    \begin{macrocode}
\cals@span@ifL\iftrue
 \cals@span@ifT\iftrue
   \cals@span@height=0pt %
 \else
   \cals@span@get
   \advance\cals@span@height by \cals@last@row@height\relax
 \fi
 \cals@span@ifB\iftrue \else
  \let\cals@ifInRspan=\cals@iftrue
  \let\cals@ifLastRspanRow=\cals@iffalse
 \fi
 \let\cals@span@borderL=\cals@borderL \let\cals@span@borderT=\cals@borderT
 \let\cals@span@borderR=\cals@borderR \let\cals@span@borderB=\cals@borderB
\fi
%    \end{macrocode}
% Action "r": put the data to the queue, unless in the end of the spanning.
%    \begin{macrocode}
\cals@span@ifR\iftrue
 \cals@span@ifB\iftrue \relax \else \cals@span@put \fi
\fi
%    \end{macrocode}
% Update the current row or calculate the span width
% (in the case of the bottom row).
%    \begin{macrocode}
\cals@span@ifB\iftrue
 \cals@span@ifL\iftrue
  \cals@span@width=\cals@nullcell@width\relax
 \else
  \advance\cals@span@width by \cals@nullcell@width\relax
 \fi
\else
 \setbox\cals@current@row=\hbox{%
   \unhbox\cals@current@row
   \vbox{\hbox to\cals@nullcell@width{}\vfil}}%
\fi
%    \end{macrocode}
% Update decorations
%    \begin{macrocode}
\cals@span@ifL\iftrue \let\cals@borderL=\cals@span@borderL
  \else \def\cals@borderL{0pt}\fi
\cals@span@ifT\iftrue \let\cals@borderT=\cals@span@borderT
  \else \def\cals@borderT{0pt}\fi
\cals@span@ifR\iftrue \let\cals@borderR=\cals@span@borderR
  \else \def\cals@borderR{0pt}\fi
\cals@span@ifB\iftrue \let\cals@borderB=\cals@span@borderB
  \else \def\cals@borderB{0pt}\fi
\cals@decor@next\cals@nullcell@width
\let\cals@borderL=\cals@span@borderL \let\cals@borderR=\cals@span@borderR
\let\cals@borderT=\cals@span@borderT \let\cals@borderB=\cals@span@borderB
}
%    \end{macrocode}
% \end{macro}

% \begin{macro}{\cals@span@width}
% \begin{macro}{\cals@span@height}
% The width of the span cell. The height of the spanned cell (without
% the last row).
%    \begin{macrocode}
\newdimen\cals@span@width
\newdimen\cals@span@height
%    \end{macrocode}
% \end{macro}
% \end{macro}

% \begin{macro}{\cals@ifInRspan}
% Set to |\cals@iftrue| if the current row is a part of a row span.
% Otherwise |\cals@iffalse|.
% \end{macro}

% \begin{macro}{\cals@ifLastRspanRow}
% Set to |\cals@iftrue| if the current row is the last row of
% of a row span. Otherwise |\cals@iffalse|.
% \end{macro}

% \begin{macro}{\cals@updateRspanMarkers}
% Resets the span markers, which are later updated by |\nullcell|
% to the correct state for the current row.
%    \begin{macrocode}
\newcommand\cals@updateRspanMarkers{%
\ifx \empty\cals@spanq@heights
 \let\cals@ifInRspan=\cals@iffalse
\else
 \let\cals@ifInRspan=\cals@iftrue
\fi
\let\cals@ifLastRspanRow=\cals@iftrue}
%    \end{macrocode}
% \end{macro}