%dashline.sty
% This file adds the commands \dashline, \dashvector, \dotline, \dotvector
% to the range of picture items.
% 
% The dot commands seem to be working quite well, although the arrow heads
% seem a little misplaced sometimes (Why??).
% The dash commands are not working so well, and are actually uncompleted.
% Basically I lost interest when I realised how big the dashes had to be
% to use the current line font.

%problems:
% hdashline always works from left to right, so dashes are not symmetrical.
% Last dash is larger to make up the length. How about about spreading the gap?
% (I actually have spread the gap in the dots routines, so just copy this.)
% vdashline has not been implemented.

\def\dotline(#1,#2)#3{\@xarg #1\relax \@yarg #2\relax
\@linelen #3\unitlength 
\ifnum\@xarg=\z@\@vdotline\else\@sdotline\fi}

\def\@sdotline{\ifnum\@xarg<\z@ \@negargtrue \@xarg -\@xarg \@yyarg -\@yarg
  \else \@negargfalse \@yyarg \@yarg \fi
  \ifnum\@yarg<\z@ \@tempcnta-\@yarg \else \@tempcnta\@yarg \fi
  \@tempdima2pt\ifnum\@xarg<\@tempcnta 
    \divide\@tempdima\@tempcnta \multiply\@tempdima\@xarg
  \fi
  \@tempdimb\@linelen
  \advance\@tempdimb0.5\@tempdima \@tempcntb\@tempdimb 
  \divide\@tempcntb\@tempdima  %\@tempcntb now contains the number of dots.
  \@tempdima\@linelen \divide\@tempdima\@tempcntb
  \setbox\@dashbox\hbox to\@tempdima{\hss .\hss}%
  \divide\@tempdima\@xarg \multiply\@tempdima\@tempcnta
  \setbox\@dashbox\vbox to\@tempdima{\vss \box\@dashbox\vss}%
  \ht\@dashbox0.5\@tempdima \dp\@dashbox0.5\@tempdima
%\showthe\wd\@dashbox \showthe\ht\@dashbox \showthe\dp\@dashbox
  \ifnum \@yarg >\z@ \let\@upordown\raise\else\let\@upordown\lower\fi
  \@clnwd \z@ \@clnht \z@
  \if@negarg \def\@tempa{\hskip -2\wd\@dashbox}\else \let\@tempa\relax\fi
  \hskip -0.5\wd\@dashbox
  \@whiledim \@clnwd <\@linelen \do
   {\@upordown\@clnht\copy\@dashbox
    \@tempa
    \advance\@clnht 2\ht\@dashbox
    \advance\@clnwd \wd\@dashbox}%
  \if@negarg \hskip \wd\@dashbox\fi
}

\def\@vdotline{\@tempdima2pt\@tempdimb\@linelen
  \advance\@tempdimb0.5\@tempdima \@tempcntb\@tempdimb 
  \divide\@tempcntb\@tempdima  %\@tempcntb now contains the number of dots.
  \@tempdima\@linelen \divide\@tempdima\@tempcntb
  \setbox\@dashbox\vbox to\@tempdima{\vss \hbox to\z@{\hss .\hss}\vss}%
  \ht\@dashbox0.5\@tempdima \dp\@dashbox0.5\@tempdima
%\showthe\wd\@dashbox \showthe\ht\@dashbox \showthe\dp\@dashbox
  \ifnum \@yarg >\z@ \let\@upordown\raise\else\let\@upordown\lower\fi
  \@clnht \z@
  \@whiledim \@clnht <\@linelen \do
   {\@upordown\@clnht\copy\@dashbox
    \advance\@clnht 2\ht\@dashbox}%
}

\def\dotvector(#1,#2)#3{\@xarg #1\relax \@yarg #2\relax
\@tempcnta \ifnum\@xarg<\z@ -\@xarg\else\@xarg\fi
\ifnum\@tempcnta<5\relax
\@linelen #3\unitlength
\ifnum\@xarg =\z@ \@vdotvector \else \@sdotvector \fi
\else\@badlinearg\fi}
 
\def\@sdotvector{\@sdotline
\@tempcnta\@yarg \ifnum\@tempcnta <\z@ \@tempcnta -\@tempcnta\fi
\ifnum\@tempcnta <5\relax
  \setbox\@tempboxa\hbox to\z@{\@linefnt  \if@negarg
  \@getlarrow(\@xarg,\@yyarg)\hss\else \hss\@getrarrow(\@xarg,\@yyarg)\fi}%
  \ifnum \@yarg >\z@ \advance\@clnht-\ht\@tempboxa\fi
  \@upordown\@clnht\box\@tempboxa
\else\@badlinearg\fi}

\def\@vdotvector{\ifnum \@yarg <\z@ \@downdotvector \else \@updotvector \fi}

\def\@updotvector{\@vdotline\setbox\@tempboxa\hbox{\@linefnt\char'66}\raise
     \@linelen \hbox to\z@{\lower \ht\@tempboxa\box\@tempboxa\hss}}
 
\def\@downdotvector{\@vdotline\lower \@linelen
      \hbox to \z@{\@linefnt\char'77\hss}}

\def\dashline(#1,#2)#3{\@xarg #1\relax \@yarg #2\relax
\@linelen #3\unitlength
\ifnum\@xarg =\z@ \@vdashline
  \else \ifnum\@yarg =\z@ \@hdashline \else \@sdashline\fi
\fi}
 
\def\@sdashline{\ifnum\@xarg<\z@ \@negargtrue \@xarg -\@xarg \@yyarg -\@yarg
  \else \@negargfalse \@yyarg \@yarg \fi
\ifnum \@yyarg >\z@ \@tempcnta\@yyarg \else \@tempcnta -\@yyarg \fi
\ifnum\@tempcnta>6 \@badlinearg\@tempcnta\z@ \fi
\ifnum\@xarg>6 \@badlinearg\@xarg \@ne \fi
\setbox\@linechar\hbox{\@linefnt\@getlinechar(\@xarg,\@yyarg)}%
\ifnum \@yarg >\z@ \let\@upordown\raise \@clnht\z@
   \else\let\@upordown\lower \@clnht \ht\@linechar\fi
\@clnwd \wd\@linechar
\if@negarg \hskip -\wd\@linechar \def\@tempa{\hskip -3\wd\@linechar}\else
     \def\@tempa{\hskip \wd\@linechar}\fi
\@whiledim \@clnwd <\@linelen \do
  {\@upordown\@clnht\copy\@linechar
   \@tempa
   \advance\@clnht 2\ht\@linechar
   \advance\@clnwd 2\wd\@linechar}%
\advance\@clnht -2\ht\@linechar
\advance\@clnwd -2\wd\@linechar
\@tempdima\@linelen\advance\@tempdima -\@clnwd
\@tempdimb\@tempdima\advance\@tempdimb -2\wd\@linechar
\if@negarg \hskip -\@tempdimb \else \hskip \@tempdimb \fi
\multiply\@tempdima 500
\@tempcnta \@tempdima \@tempdima \wd\@linechar \divide\@tempcnta \@tempdima
\@tempdima \ht\@linechar \multiply\@tempdima \@tempcnta
\divide\@tempdima 500
\advance\@clnht \@tempdima
\ifdim \@linelen <\wd\@linechar
   \hskip \wd\@linechar
  \else\@upordown\@clnht\copy\@linechar\fi}
 
\def\@hdashline{\ifnum \@xarg <\z@ \hskip -\@linelen \fi
\leavevmode\hbox to\z@{\baselineskip \z@
\lineskip \z@
\@dashdim \@linelen
\@dashcnt \@dashdim \advance\@dashcnt 200
\@dashdim 10pt\divide\@dashcnt \@dashdim
%\showthe\@dashcnt
\ifodd\@dashcnt\@dashdim \z@
\advance\@dashcnt \@ne \divide\@dashcnt \tw@
\else \divide\@dashdim \tw@ \divide\@dashcnt \tw@
\advance\@dashcnt \m@ne
\setbox\@dashbox \hbox{\vrule \@height \@halfwidth \@depth \@halfwidth
\@width \@dashdim}\put(0,0){\copy\@dashbox}%
\put(0,0){\hskip \@linelen\hskip-\@dashdim\copy\@dashbox\hskip -\@linelen}%
\multiply\@dashdim \thr@@
\fi
\setbox\@dashbox \hbox{\vrule \@height \@halfwidth \@depth \@halfwidth
\@width 10pt\hskip 10pt}\@tempcnta\z@
\put(0,0){\hskip\@dashdim \@whilenum \@tempcnta <\@dashcnt
\do{\copy\@dashbox\advance\@tempcnta \@ne }}\@tempcnta\z@\hss
}%end of hbox
\ifnum \@xarg <\z@ \else\hskip \@linelen \fi}
 
\def\dashvector(#1,#2)#3{\@xarg #1\relax \@yarg #2\relax
\@tempcnta \ifnum\@xarg<\z@ -\@xarg\else\@xarg\fi
\ifnum\@tempcnta<5\relax
\@linelen #3\unitlength
\ifnum\@xarg =\z@ \@vdashvector
  \else \ifnum\@yarg =\z@ \@hdashvector \else \@sdashvector\fi
\fi
\else\@badlinearg\fi}
 
\def\@hdashvector{\@hdashline\hbox to\z@{\@linefnt
\ifnum \@xarg <\z@ \@getlarrow(1,0)\hss\else
    \hss\@getrarrow(1,0)\fi}}
 
\def\@vdashvector{\ifnum \@yarg <\z@ \@downdashvector \else \@updashvector \fi}
 
\def\@sdashvector{\@sdashline
\@tempcnta\@yarg \ifnum\@tempcnta <\z@ \@tempcnta -\@tempcnta\fi
\ifnum\@tempcnta <5%
  \hskip -\wd\@linechar
  \@upordown\@clnht \hbox{\@linefnt  \if@negarg
  \@getlarrow(\@xarg,\@yyarg)\else \@getrarrow(\@xarg,\@yyarg)\fi}%
\else\@badlinearg\fi}

\def\@vdashline{%\ifnum \@yarg <\z@ \@downdashline \else \@updashline\fi}
\@dashdim \@linelen
\@dashcnt \@dashdim \advance\@dashcnt 200
\@dashdim 10pt\divide\@dashcnt \@dashdim
\ifodd\@dashcnt \@dashdim \z@
\advance\@dashcnt \@ne \divide\@dashcnt \tw@
\else
\divide\@dashdim \tw@ \divide\@dashcnt \tw@
\advance\@dashcnt \m@ne
\setbox\@dashbox\hbox{\hskip -\@halfwidth
\vrule \@width \@wholewidth
\@height \@dashdim}\put(0,0){\copy\@dashbox}%
%\put(0,#3){\lower\@dashdim\copy\@dashbox}%
\multiply\@dashdim \thr@@
\fi
\setbox\@dashbox\hbox{\vrule \@width \@wholewidth
\@height 10pt\unitlength}\@tempcnta\z@
\put(0,0){\hskip -\@halfwidth \vbox{\@whilenum \@tempcnta <\@dashcnt
\do{\vskip 10pt\unitlength\copy\@dashbox\advance\@tempcnta \@ne }%
\vskip\@dashdim}}\@tempcnta\z@
} 
\def\@updashline{\hbox to \z@{\hskip -\@halfwidth \vrule \@width \@wholewidth
   \@height \@linelen \@depth \z@\hss}}
 
\def\@downdashline{\hbox to \z@{\hskip -\@halfwidth \vrule \@width \@wholewidth
   \@height \z@ \@depth \@linelen \hss}}
 
\def\@updashvector{\@updashline\setbox\@tempboxa\hbox{\@linefnt\char'66}\raise
     \@linelen \hbox to\z@{\lower \ht\@tempboxa\box\@tempboxa\hss}}
 
\def\@downdashvector{\@downdashline\lower \@linelen
      \hbox to \z@{\@linefnt\char'77\hss}}