%
%  `vowel.sty' -- for drawing vowel diagrams.
%
%  Copyright(C) 1996 by FUKUI Rei
%
%  Version 1.0 1996/06/10
%  
%  This file is distributed with TIPA.
%
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{vowel}[1996/06/10 VOWEL Package version 1.0]

% The following macros are defined in `tipa' so that they are defined
% only if `tipa' has not been loaded.

\@ifundefined{super}{\let\super\textsuperscript}{}

% The following parameters can be overrided by the user.
% -\p@ is used as the initial value instead of \z@ because a user can
% specify 0pt, for example, for \vowelsep. This initial value is later
% used to find out whether or not the user has modified it.

\newdimen\vowelhunit \vowelhunit-\p@
\newdimen\vowelvunit \vowelvunit-\p@
\newdimen\vowelsep \vowelsep-\p@
\newdimen\vowelline \vowelline.4pt
\newcommand\vowelsymbol{\lower.72ex\hbox{\textsuperscript{$\bullet$}}}
\newcommand\diagrate{.4}

% Internal registers, etc.

\newcount\@vwlcnt \@vwlcnt\@ne
\newdimen\@vwltopsep \@vwltopsep\z@
\newdimen\@vwlbotsep \@vwlbotsep\z@
\newdimen\@vwllftsep \@vwllftsep\z@
\newdimen\@vwlrtsep \@vwlrtsep\z@
\newif\if@notouch
\newif\if@tmpnoerase \@tmpnoerasefalse
\newif\if@vline \@vlinefalse

% \@dgmtype 0:plain, 1:simple, 2:standard, 3:ipanew (default)
\newcount\@dgmtype \@dgmtype=3
% \@dgmaligh 0: default(mid), 1: top, 2: bot
\newcount\@dgmalign \@dgmalign=0
\newif\ifrectdgm \rectdgmfalse
\newif\iftriangledgm \triangledgmfalse
\newif\ifthreelevel \threelevelfalse
\newif\ifnoerase \noerasefalse

\newcommand\incrz@{\advance\dimen\z@}
\newcommand\incr@ne{\advance\dimen\@ne}

\def\@ipanewdgm{ipanew}
\def\@stddgm{standard}
\def\@simpledgm{simple}
\def\@plaindgm{plain}
\def\@threelevel{three}
\def\@rectdgm{rectangle}
\def\@triangledgm{triangle}
\def\@noerase{noerase}
\def\@dgmtopalign{t}
\def\@dgmbotalign{b}

% Definition of the vowel environment.

\newenvironment{vowel}{\@ifnextchar[{\@vowel}{\@vowel[]}}{\@@vowel}

\def\@vowel[#1]{\leavevmode
  \@for\@vwloption:=#1\do{%
    \ifx\@vwloption\@ipanewdgm\else 
    \ifx\@vwloption\@stddgm \@dgmtype=2\else
    \ifx\@vwloption\@simpledgm \@dgmtype=1\else
    \ifx\@vwloption\@plaindgm \@dgmtype=0\else
    \ifx\@vwloption\@rectdgm \rectdgmtrue\else
    \ifx\@vwloption\@triangledgm \triangledgmtrue\else
    \ifx\@vwloption\@threelevel \threeleveltrue\else
    \ifx\@vwloption\@noerase \noerasetrue\else
    \ifx\@vwloption\@dgmtopalign \@dgmalign=1\else
    \ifx\@vwloption\@dgmbotalign \@dgmalign=2\else
    \errmessage{vowel: no such option [\@vwloption]}%
    \fi\fi\fi\fi\fi\fi\fi\fi\fi\fi}\relax
%
% If \vowelhunit, \vowelvunit, and \vowelsep are not overrided by a user,
% use default values.
%
  \ifdim\vowelhunit=-\p@ \vowelhunit2em\fi
  \ifdim\vowelvunit=-\p@ \vowelvunit=\ifthreelevel1.5\fi\vowelhunit\fi
  \ifdim\vowelsep=-\p@ \vowelsep.16em\fi
  \dimen\@ne=4\vowelhunit
  \edef\@vwldgmwd{\the\dimen\@ne}%
  \edef\@vwldgmht{\ifthreelevel2\else3\fi\vowelvunit}%
  \edef\c@rdhposii{\ifrectdgm\z@\else\ifthreelevel\else.667\fi\vowelhunit\fi}%
  \edef\c@rdhposiii{\ifrectdgm\z@\else1.333\vowelhunit\fi}%
  \edef\c@rdhposiv{\ifrectdgm\z@\else2\vowelhunit\fi}%
  \edef\c@rdhposx{\ifrectdgm2\else2.333\fi\vowelhunit}%
  \edef\c@rdhposxi{\ifrectdgm2\else2.5\fi\vowelhunit}%
  \edef\c@rdhposxii{\ifrectdgm2\else2.667\fi\vowelhunit}%
  \edef\c@rdhposxiii{\ifrectdgm\else1.25\fi\vowelhunit}%
  \edef\c@rdhposxiv{\ifrectdgm3\else3.083\fi\vowelhunit}%
  \edef\c@rdhposxv{\ifrectdgm2\else2.833\fi\vowelhunit}%
  \edef\c@rdhposxvi{\ifrectdgm\z@\else1.667\vowelhunit\fi}%
}

\newcommand\@vwldgmhline[2]{%
  \kern-.5\vowelline
  \dimen\z@\@vwldgmwd
  \iftriangledgm \incrz@-#1\fi
  \edef\@vwltmpi{\the\dimen\z@}%
  \hb@xt@ \@vwldgmwd{\@bgline{#1}\@vwltmpi{#2}\relax\hss}%
  \kern.5\vowelline
}

% This is the main macro.
\newcommand\@@vowel{%
  \ifcase\@dgmalign
    \advance\@vwltopsep4pt \advance\@vwlbotsep4pt \or
    \advance\@vwltopsep-1ex  \advance\@vwlbotsep4pt \or
    \advance\@vwltopsep4pt \fi
  \def\@lasthpos{\z@}%
  \dimen\z@\@vwldgmht
  \incrz@ \vowelline
  \incrz@ \@vwltopsep
  \incrz@ \@vwlbotsep
  \dimen\@ne\dimen\z@
  \ifcase\@dgmalign
    \dimen\z@.5\dimen\z@ \dimen\@ne.5\dimen\@ne \or
    \dimen\z@\z@ \or
    \dimen\@ne\z@ \fi
  \hbox{\kern\@vwllftsep
    \vrule \@height\dimen\z@ \@depth\dimen\@ne \@width\z@
    \ifnum\@dgmalign=1\vtop\else\vbox\fi to\dimen\z@{%
      \hsize\@vwldgmwd\offinterlineskip
      \kern\@vwltopsep
      \@drawvowel{\the\@vwlcnt}%
%
      \vtop to\z@{\hb@xt@ \@vwldgmwd{%
        {\@vlinetrue
          \ifrectdgm \@bgline\z@\@vwldgmht\z@\relax
          \else \@bgline\z@\@vwldgmht\z@\c@rdhposiv \fi
%
          \ifnum \@dgmtype=3% ipanew
            \ifrectdgm \@bgline\z@\@vwldgmht\c@rdhposx\relax
            \else\iftriangledgm \@bgline\z@\@vwldgmht\c@rdhposiv\relax
            \else \@bgline\z@\@vwldgmht\c@rdhposiv{3\vowelhunit}\fi\fi
          \else \ifnum\@dgmtype=2% standard
            \@bgline\z@{2.5\vowelvunit}{1.167\vowelhunit}\c@rdhposxv
            \@bgline\z@{2.5\vowelvunit}\c@rdhposiv\c@rdhposxv
            \@bgline\z@{2.5\vowelvunit}\c@rdhposxv\relax
          \fi\fi
%
          \iftriangledgm
            \@bgline\z@\@vwldgmht\@vwldgmwd\c@rdhposiv
          \else
            \@bgline\z@\@vwldgmht\@vwldgmwd\relax \fi
          }\hss}\vss}%
%
      \@vwldgmhline\z@\z@
      \kern\vowelvunit
      \ifnum\@dgmtype>0\kern-\vowelline
        \@vwldgmhline\c@rdhposii\vowelvunit\fi
      \kern\vowelvunit
      \ifthreelevel\else
        \ifnum\@dgmtype>0\kern-\vowelline
          \@vwldgmhline\c@rdhposiii{2\vowelvunit}\fi
        \kern\vowelvunit\fi
      \kern-\vowelline
      \@vwldgmhline\c@rdhposiv\@vwldgmht
      \kern\@vwlbotsep
      \vss}%
    \kern\@vwlrtsep}%
}

% Commands for placing vowels on the vowel diagram.

\newcommand\putvowel{\@ifnextchar[{\@putdotvowel}{\@putvowel}}

% Put a vowel on a specified point.
\newcommand\@putvowel[3]{%
  \setbox\z@\hbox{#1\global\dimen4=.5ex}%
  \setbox\z@\hbox{#1}\dimen\@ne\wd\z@\incr@ne 2\vowelsep
%
  \dimen\z@#2\incrz@ -.5\dimen\@ne
  \expandafter\xdef\csname vwlxi\the\@vwlcnt\endcsname{\the\dimen\z@}%
  \ifdim\dimen\z@<\z@ \dimen\z@-\dimen\z@
    \ifdim\dimen\z@>\@vwllftsep \@vwllftsep\dimen\z@\fi\fi
%
  \dimen\z@#2\incrz@ .5\dimen\@ne
  \expandafter\xdef\csname vwlxii\the\@vwlcnt\endcsname{\the\dimen\z@}%
  \dimen\@ne\@vwldgmwd \incr@ne-\dimen\z@
  \ifdim\dimen\@ne<\z@ \dimen\@ne-\dimen\@ne
    \ifdim\dimen\@ne>\@vwlrtsep \@vwlrtsep\dimen\@ne\fi\fi
%
  \dimen\z@#3\dimen\tw@=\ht\z@\advance\dimen\tw@ -\dimen4%.5ex%
  \incrz@ -\dimen\tw@ \incrz@ -\vowelsep
  \expandafter\xdef\csname vwlyi\the\@vwlcnt\endcsname{\the\dimen\z@}%
  \ifdim\dimen\tw@>\@vwltopsep \@vwltopsep\dimen\tw@\fi
%
  \dimen\z@#3\dimen\tw@=\dp\z@\advance\dimen\tw@ \dimen4%.5ex%
  \incrz@ \dimen\tw@ \incrz@ \vowelsep
  \expandafter\xdef\csname vwlyii\the\@vwlcnt\endcsname{\the\dimen\z@}%
  \ifdim\dimen\tw@>\@vwlbotsep \@vwlbotsep\dimen\tw@\fi
%
  \expandafter\gdef\csname vwlsym\the\@vwlcnt\endcsname{#1}%
  \expandafter\xdef\csname tmpnoerase\the\@vwlcnt\endcsname{%
    \if@tmpnoerase1\else0\fi}%
  \advance\@vwlcnt \@ne
  \ignorespaces}

\def\@putdotvowel[#1]#2#3#4{%
  \if x#1\@putvowel{#2}{#3}{#4}\else
  \@tmpnoerasetrue\@putvowel\vowelsymbol{#3}{#4}\@tmpnoerasefalse
  \setbox\z@\hbox{#2}\setbox\@ne\hbox{\vowelsymbol}%
  \dimen\z@=#3\dimen\@ne=#4\dimen\tw@=.5\wd\z@
  \advance\dimen\tw@.5\wd\@ne \advance\dimen\tw@.5\vowelsep
%
  \if l#1%
    \incrz@-\dimen\tw@
  \else
    \if r#1\incrz@\dimen\tw@
    \else \errmessage{put(c)vowel: no such option [#1]}%
    \fi
  \fi
%
  \edef\@vwltmpi{\the\dimen\z@}%
  \@putvowel{#2}\@vwltmpi{#4}\fi}

% Put a vowel on a cardinal position
\newcommand\putcvowel{\@ifnextchar[{\@putcvowel}{\@putcvowel[x]}}

\def\@putcvowel[#1]#2#3{%
  \ifcase#3\or
    \@putdotvowel[#1]{#2}\z@\z@\or
    \@putdotvowel[#1]{#2}\c@rdhposii\vowelvunit\or
    \@putdotvowel[#1]{#2}\c@rdhposiii{2\vowelvunit}\or
    \@putdotvowel[#1]{#2}\c@rdhposiv\@vwldgmht\or
    \@putdotvowel[#1]{#2}\@vwldgmwd\@vwldgmht\or
    \@putdotvowel[#1]{#2}\@vwldgmwd{2\vowelvunit}\or
    \@putdotvowel[#1]{#2}\@vwldgmwd\vowelvunit\or
    \@putdotvowel[#1]{#2}\@vwldgmwd\z@\or
    \@putdotvowel[#1]{#2}{2\vowelhunit}\z@\or
    \@putdotvowel[#1]{#2}\c@rdhposx\vowelvunit\or
    \@putdotvowel[#1]{#2}\c@rdhposxi{1.5\vowelvunit}\or
    \@putdotvowel[#1]{#2}\c@rdhposxii{2\vowelvunit}\or
    \@putdotvowel[#1]{#2}\c@rdhposxiii{.5\vowelvunit}\or
    \@putdotvowel[#1]{#2}\c@rdhposxiv{.5\vowelvunit}\or
    \@putdotvowel[#1]{#2}\c@rdhposxv{2.5\vowelvunit}\or
    \@putdotvowel[#1]{#2}\c@rdhposxvi{2.5\vowelvunit}\else\fi
}

\newcommand\@getvwldim[1]{%
  \edef\@vwlyi{\csname vwlyi\the#1\endcsname}%
  \edef\@vwlyii{\csname vwlyii\the#1\endcsname}%
  \edef\@vwlxi{\csname vwlxi\the#1\endcsname}%
  \edef\@vwlxii{\csname vwlxii\the#1\endcsname}%
  \edef\@tmpnoerase{\csname tmpnoerase\the#1\endcsname}%
  \if@vline
    \let\@lineposi\@vwlxi \let\@lineposii\@vwlxii
    \let\@vwlposi\@vwlyi \let\@vwlposii\@vwlyii
  \else
    \let\@lineposi\@vwlyi \let\@lineposii\@vwlyii
    \let\@vwlposi\@vwlxi \let\@vwlposii\@vwlxii
  \fi
}

\newcommand\@drawvowel[1]{{%
  \@vwlcnt#1\relax
  \loop
    \advance\@vwlcnt\m@ne
    \ifnum \@vwlcnt>\z@
      \@getvwldim\@vwlcnt
      \dimen\z@\@vwlxi \incrz@\vowelsep
      \incrz@ .5\vowelline
      \vtop to \z@{%
        \kern\@vwlyi
        \kern\vowelsep
        \hb@xt@\z@{\kern\dimen\z@\csname vwlsym\the\@vwlcnt\endcsname\hss}%
        \vss}%
  \repeat
}}

{\catcode`\p=12\catcode`\t=12\gdef\@chreal#1.#2pt{#1}}

\newcount\@x@ \newcount\@y@ \newcount\@z@

\newcommand\@dimdivide[2]{{%
  \dimen\z@#1\dimen\@ne#2\def\@sign{}%
  \ifdim\dimen\z@<\z@ \dimen\z@-\dimen\z@
    \ifdim\dimen\@ne<\z@ \dimen\@ne-\dimen\@ne \else \def\@sign{-}\fi
  \else
    \ifdim\dimen\@ne<\z@ \dimen\@ne-\dimen\@ne \def\@sign{-}\fi
  \fi
  \ifdim\dimen\z@>100pt\def\@enl@rge{10}\else
  \ifdim\dimen\@ne>100pt\def\@enl@rge{10}\else
  \ifdim\dimen\z@>10pt\def\@enl@rge{100}\else
  \ifdim\dimen\@ne>10pt\def\@enl@rge{100}\else
  \def\@enl@rge{\@m}\fi\fi\fi\fi
  \dimen\z@=\@enl@rge\dimen\z@ \dimen\@ne\@enl@rge\dimen\@ne
  \@x@=\expandafter\@chreal\the\dimen\z@
  \@y@=\expandafter\@chreal\the\dimen\@ne
  \divide\@x@ \@y@ \edef\@dimrate{\the\@x@.}%
  \@z@=\@x@ \multiply\@z@ \@y@
  \@x@=\expandafter\@chreal\the\dimen\z@ \advance\@x@ -\@z@
  \multiply\@x@ 10 \edef\@vwltmpi{\the\@x@}%
  \divide\@x@ \@y@ \edef\@dimrate{\@dimrate\the\@x@}%
  \@@dimdivide\@@dimdivide\@@dimdivide
  \xdef\@dimrate{\@sign\@dimrate}%
}}

\newcommand\@@dimdivide{%
  \@z@=\@x@ \multiply\@z@ \@y@
  \@x@=\@vwltmpi \advance\@x@ -\@z@
  \multiply\@x@ 10 \edef\@vwltmpi{\the\@x@}%
  \divide\@x@ \@y@ \edef\@dimrate{\@dimrate\the\@x@}}

\newcommand\@drawhline[3]{{%
  \dimen\z@#1\dimen\@ne#2\incr@ne-\dimen\z@
  \hb@xt@\z@{%
    \kern\dimen\z@
    \kern.5\vowelline
    \vrule \@height\vowelline \@depth\z@ \@width\dimen\@ne \hss}%
}}

\newcommand\@drawvline[3]{{%
  \dimen\z@#1\dimen\@ne#2\dimen\tw@#3%
  \incr@ne -\dimen\z@
  \hb@xt@ \z@{\kern\dimen\tw@\vtop to\z@{%
    \kern\dimen\z@
    \hrule \@height\dimen\@ne \@depth\z@ \@width\vowelline \vss}\hss}%
}}

\newcommand\@drawdiagline[4]{{%
  \dimen\z@#1\dimen\@ne#2%
  \incr@ne -\dimen\z@
  \dimen\tw@#3\dimen\thr@@#4%
  \ifdim\dimen\tw@>\dimen\thr@@
    \dimen\tw@#4\dimen\thr@@#3%
    \advance\dimen\thr@@ -\dimen\tw@
    \dimen\thr@@-\dimen\thr@@
  \else
    \advance\dimen\thr@@ -\dimen\tw@
  \fi
  \hb@xt@ \z@{\kern\dimen\tw@\vtop to\z@{%
    \kern\dimen\z@
    \diagline{\the\dimen\@ne}{\the\dimen\thr@@}%
    \vss}\hss}%
}}

% This is the memory-eater.

\newcommand\diagline[2]{%
  \@dimdivide{#1}{#2}\dimen\@ne=\diagrate\vowelline
  \ifdim\dimen\@ne>.4pt\dimen\@ne=.4pt\fi
  \dimen4=-\@dimrate\dimen\@ne \dimen\z@=\z@
  \dimen\tw@=#2\relax \ifdim\dimen\tw@<\z@ \dimen\tw@-\dimen\tw@\fi
  \advance\dimen\tw@ -.25\vowelline
  \setbox\@ne\hbox{}%
  \loop \setbox\z@\hbox{\unhcopy\@ne}%
    \ifdim\wd\z@<\dimen\tw@
       \setbox\@ne\hbox{\unhbox\z@\raise\dimen\z@\hb@xt@ \z@{%
        \vrule\@width\vowelline\@height\vowelline\hss}%
        \kern\dimen\@ne}%
      \global\incrz@ \dimen4
  \repeat
  \box\@ne}

% Macros for background lines:
%
% The next macros are the most interesting ones in this package. They
% are used to draw horizontal, vertical or diagonal lines, recursively 
% checking the positions of all the \hboxes and if an \hbox is on the
% line, that part of the line is erased.
%
% `\@bgline' is simply an interface to the main macros, `\@@bgline' and
% `\@@bgdline'. The former is used to draw horizontal or vertical
% lines, and the latter diagonal lines. The main macros are defined
% without parameters, because a recursive macro with many parameters
% is likely to eat up TeX's parameter stack. (This annoyed the author
% indeed at the first stage of the development of this package.

\newcommand\@bgline[4]{{%
  \edef\@starti{#1}\edef\@endi{#2}%
  \edef\@startii{#3}\edef\@endii{#4}%
  \ifx#4\relax
    \ifnoerase
      \if@vline \@drawvline\@starti\@endi\@startii
      \else \@drawhline\@starti\@endi\@startii\fi
    \else \@@bgline\fi
  \else
    \@setupdiag
    \ifnoerase \@drawdiagline\@starti\@endi\@startii\@endii
    \else \@@bgdline\fi
  \fi}}

\newcommand\@@bgline{%
  \@notouchfalse
  \advance\@vwlcnt \m@ne
  \ifnum \@vwlcnt < \@ne
    \if@vline \@drawvline\@starti\@endi\@startii
    \else \@drawhline\@starti\@endi\@startii\fi
  \else
    \@getvwldim\@vwlcnt
    \ifnum\@tmpnoerase=0\relax
      \ifdim \@lineposi<\@startii
        \ifdim \@lineposii>\@startii
          \ifdim \@vwlposii<\@starti\relax
            \@notouchtrue
          \else
            \ifdim \@vwlposi>\@endi\relax
              \@notouchtrue
            \else
              \ifdim \@vwlposi>\@starti
                \ifdim \@vwlposii<\@endi
                  {\edef\@endi{\@vwlposi}\@@bgline}% split
                  {\edef\@starti{\@vwlposii}\@@bgline}%
                \else
                  {\edef\@endi{\@vwlposi}\@@bgline}%
                \fi
              \else
                \ifdim \@vwlposii<\@endi
                  {\edef\@starti{\@vwlposii}\@@bgline}\fi
              \fi
            \fi
          \fi
        \else
          \@notouchtrue
        \fi
      \else
        \@notouchtrue
      \fi
    \else
      \@notouchtrue
    \fi
  \fi
  \if@notouch \@@bgline\fi
}

\newcommand\@setupdiag{%
  \dimen\z@\@endii\dimen\@ne\@startii\incrz@-\dimen\@ne
  \dimen\@ne\@endi\dimen\tw@\@starti\incr@ne-\dimen\tw@
  \edef\@vwltmpi{\the\dimen\z@}\edef\@vwltmpii{\the\dimen\@ne}%
  \@dimdivide\@vwltmpi\@vwltmpii\edef\@xrate{\@dimrate}%
  \@dimdivide\@vwltmpii\@vwltmpi\edef\@yrate{\@dimrate}%
  \edef\@diagxoffset{\@startii}%
}

\newcommand\@getx[2]{%
  \dimen\z@#1\dimen\@ne\@xrate\dimen\z@
  \incr@ne\@diagxoffset
  \edef#2{\the\dimen\@ne}}

\newcommand\@gety[2]{%
  \dimen\z@#1\incrz@-\@diagxoffset
  \dimen\@ne\@yrate\dimen\z@
  \edef#2{\the\dimen\@ne}}

\newcommand\@checktouch[4]{%
  \dimen\tw@#2\dimen\thr@@#3\@getx{#1}#4%
  \ifdim \dimen\@ne<\dimen\tw@ \def#4{}\fi
  \ifdim \dimen\@ne>\dimen\thr@@ \def#4{}\fi
}
     
\newcommand\@dimswap[2]{%
  \ifdim \@xrate pt<\z@
    \edef\@vwltmpi{#1}\edef#1{#2}\edef#2{\@vwltmpi}\fi}

\newcommand\@@bgdline{%
  \dimen\z@\@endi \dimen\@ne\@starti \incrz@-\dimen\@ne
  \ifdim \dimen\z@<\vowelsep\else % ignore short line
    \@notouchfalse
    \advance\@vwlcnt \m@ne
    \ifnum \@vwlcnt < \@ne
      \@drawdiagline\@starti\@endi\@startii\@endii
    \else
      \@getvwldim\@vwlcnt
      \ifnum\@tmpnoerase=0\relax
        \@dimswap\@startii\@endii
        \ifdim \@lineposi<\@endii
          \ifdim \@lineposii>\@startii
          \else \@notouchtrue \fi
        \else \@notouchtrue \fi
        \@dimswap\@startii\@endii
        \ifdim \@vwlposi>\@endi\relax \@notouchtrue \fi
        \ifdim \@vwlposii<\@starti\relax \@notouchtrue \fi
%
        \if@notouch\else
          \@checktouch\@vwlposi\@lineposi\@lineposii\@topx
          \@checktouch\@vwlposii\@lineposi\@lineposii\@botx
          \@dimswap\@lineposi\@lineposii
          \ifx\empty\@topx\empty
            \ifx\empty\@botx\empty \@notouchtrue
            \else \@gety\@lineposi\@vwlposi \edef\@topx{\@lineposi}\fi
          \else
            \ifx\empty\@botx\empty
              \@gety\@lineposii\@vwlposii \edef\@botx{\@lineposii}\fi
          \fi
        \fi
%
        \dimen\z@\@vwlposii \dimen\@ne\@vwlposi \incrz@-\dimen\@ne
        \ifdim \dimen\z@<2\vowelsep \@notouchtrue \fi % ignore tiny line break
%
        \if@notouch\else
          \ifdim \@vwlposi>\@starti
            \ifdim \@vwlposii<\@endi
              {\edef\@endi{\@vwlposi}\edef\@endii{\@topx}\@@bgdline}% split
              {\edef\@starti{\@vwlposii}\edef\@startii{\@botx}\@@bgdline}%
            \else
              {\edef\@endi{\@vwlposi}\edef\@endii{\@topx}\@@bgdline}%
            \fi
          \else
            \ifdim \@vwlposii<\@endi
              {\edef\@starti{\@vwlposii}\edef\@startii{\@botx}\@@bgdline}\fi
          \fi\fi
%
      \else \@notouchtrue
      \fi
    \fi
    \if@notouch \@@bgdline\fi
  \fi
}

\endinput