複数列出力における Plain TeX の図* 相当の定義

2024-6-16 • tag-icon

以前、figure*Plain TeX のようなものを定義しようとしました。その結果、列の高さが間違ってしまいました。

vsize を記憶するというヒントがあったので、これを試してみました。次の MWE を見てください。

% For Plain LuaTeX
\catcode`@=11
\raggedbottom

\newdimen\fullhsize
\newdimen\columnsep
\columnsep 1cm
\fullhsize\hsize
\advance\hsize-\columnsep
\divide\hsize\tw@

\newdimen\fullvsize
\fullvsize\vsize

\def\fullline{\hbox to\fullhsize}
\def\makeheadline{\vbox to\z@{\vskip-22.5\p@
    \fullline{\vbox to8.5\p@{}\the\headline}\vss}\nointerlineskip}
\def\makefootline{\baselineskip24\p@\lineskiplimit\z@
    \fullline{\the\footline}}

% Twocolumn output
\newif\if@firstcolumn \@firstcolumntrue
\newbox\firstcolumn

\output={\ifvoid\widetopins\else%%%%%%%% try to change vsize
    \global\advance\vsize-\ht\widetopins
    \global\advance\vsize-\dp\widetopins\fi
    \if@firstcolumn \global\setbox\firstcolumn=\columnbox
    \global\@firstcolumnfalse
    \else
    \doubleformat \global\@firstcolumntrue\fi
    \ifnum\outputpenalty>-20000 \else\dosupereject\fi}

\def\doubleformat{\shipout\vbox{
    \makeheadline
    \ifvoid\widetopins\else\fullline{\box\widetopins}\fi
    \fullline{\box\firstcolumn\hfil\columnbox} \makefootline}
    \advancepageno
    \global\vsize\fullvsize}% reset \vsize

\def\columnbox{\leftline{\pagebody}}

% like figure* in LaTeX
\newinsert\widetopins
\skip\widetopins\z@skip
\count\widetopins=0 %%%%%%%% to change vsize manually
\dimen\widetopins=.5\vsize

\def\widetopinsert{\p@gefalse\par\begingroup
    \setbox\z@\vbox\bgroup\hsize\fullhsize}
\def\endwideinsert{\egroup
    \insert\widetopins{\penalty100 % floating insertion
    \splittopskip\z@skip
    \splitmaxdepth\maxdimen \floatingpenalty\z@
    \ifp@ge \dimen@\dp\z@
    \vbox to\vsize{\unvbox\z@\kern-\dimen@}% depth is zero
    \else \box\z@\nobreak\bigskip\fi}\endgroup}

\def\mypicture{\vrule height 100pt depth 40pt width300pt}

\def\text{Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.}

\text\text\text

\widetopinsert
\centerline{\mypicture}
\endwideinsert

\text\text\text\text\text

\bye