%D \module
%D   [       file=spac-brk,
%D        version=2023.05.23,
%D          title=\CONTEXT\ Spacing Macros,
%D       subtitle=Breaking lines,
%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.

\ifdefined\tracinglousiness \endinput \fi

\writestatus{loading}{ConTeXt Spacing Macros / Breakpoints}

\newcount\tracinglousiness

\newcount\twinslimit \twinslimit\maxcount

\registerctxluafile{spac-brk}{}
\registerctxluafile{spac-ovl}{}
\registerctxluafile{spac-twi}{}

\unprotect

\cccode \periodasciicode          \ignoretwincharactercontrolcode
\cccode \commaasciicode           \ignoretwincharactercontrolcode
\cccode \exclamationmarkasciicode \ignoretwincharactercontrolcode
\cccode \questionmarkasciicode    \ignoretwincharactercontrolcode
\cccode \colonasciicode           \ignoretwincharactercontrolcode
\cccode \semicolonasciicode       \ignoretwincharactercontrolcode

\installtexexperiment
  {parbuilder.twins}
  {\bitwiseflip\glyphoptions-\checktwinglyphoptioncode
   \lefttwindemerits 7500
   \righttwindemerits7500
   \linebreakchecks\plustwo}
  {\bitwiseflip\glyphoptions\checktwinglyphoptioncode
   \lefttwindemerits \zerocount
   \righttwindemerits\zerocount
   \linebreakchecks\zerocount}

% \lefttwindemerits 7500
% \righttwindemerits7500
%
% \permanent\protected\def\dopermittwins{\ifnum\linebreakchecks=\plustwo\linebreakchecks\zerocount\fi}
% \permanent\protected\def\doavoidtwins {\linebreakchecks\plusone}
%
% \defcsname\??aligncommand permittwins\endcsname{\toksapp\t_spac_align_collected{\dopermittwins}}
% \defcsname\??aligncommand  avoidtwins\endcsname{\toksapp\t_spac_align_collected{\doavoidtwins }}

%D This is a very experimental feature and a by product of improving inline math
%D crossing lines. As it might evolve: use with care.

\fetchmodulecommand \startshowbreakpoints   {trac-brk} % {s-lines-show.mkxl}
\fetchmodulecommand \startshowbalancepoints {trac-brk} % {s-lines-show.mkxl}

% \starttext
%     \setupalign[verytolerant]
%     \tracinglousiness1
%   % \tracinglousiness2
%     \hsize8cm \lousiness 0      \samplefile{ward} \blank
%     {\tt \the\lousiness} \blank
%     \hsize8cm \lousiness 1 11 0 \samplefile{ward} \blank
%     \hsize8cm \silliness   11   \samplefile{ward} \blank
% \stoptext

%D These macros are defined a the \LUA\ end.

\protect \endinput