% how to run.
% \input tree.sty or \documentstyle[tree]{..}
% run through latex as you normally do
% remember to send it to a postscript printer


\special{header=tree-dvips.pro}


\def\pscmd#1{\special{ps:@beginspec
/nodemargin \@int{\the\nodemargin}\space pt def %
\@int{\the\treelinewidth}\space pt setlinewidth %
\ifdim\dashlength=0pt [] 0 setdash%
/arrowwidth \@int{\the\arrowwidth}\space pt def %
/arrowlength \@int{\the\arrowlength}\space pt def %
\else [\@int{\the\dashlength}\space pt] 0 setdash \fi\space
#1 %
@endspec}}

% parameters in tree mode
\newdimen\nodemargin % 
\nodemargin=2pt
\newdimen\treelinewidth
\treelinewidth=.3pt

\def\thinline{\treelinewidth=.3pt}

\newdimen\dashlength

% \makedash{dimen}  makes dashes of dimen length if dimen = 0pt then 
% solid line
\def\makedash#1{\dashlength=#1}

\newdimen\arrowwidth
\arrowwidth 4pt
\newdimen\arrowlength
\arrowlength 4pt

{\catcode`p=12 \catcode`t=12 \gdef\wnum#1pt{#1}}
\def\@int#1{\expandafter\wnum#1}

\def\node#1#2{\leavevmode
              \setbox1=\hbox{#2}\pscmd{/#1 \@int{\the\wd1} \space pt
                                           \@int{\the\ht1} \space pt
                                           \@int{\the\dp1} \space pt
                                       node}\box1\relax}           


% A node of 0pt width and height
% \nodepoint{nodename}[horizontal displacement][vertical displacement]
% default is current point
\def\nodepoint#1{\@ifnextchar [{\@nodepoint{#1}}{\@nodepoint{#1}[0pt][0pt]}}

\def\@nodepoint#1[#2][#3]{{\@tempdima=#2 \@tempdimb=#3%
\pscmd{/nodemargin 0 def %
/#1 \@int{\the\@tempdima}\space pt \@int{\the\@tempdimb}\space pt %
rmoveto 0 0 0 node}}}

\newtoks\pos@t   \pos@t={top}    
\newtoks\pos@b   \pos@b={bottom} 
\newtoks\pos@l   \pos@l={left}   
\newtoks\pos@r   \pos@r={right}  
\newtoks\pos@tl   \pos@tl={topleft}    
\newtoks\pos@tr   \pos@tr={topright}   
\newtoks\pos@bl   \pos@bl={bottomleft} 
\newtoks\pos@br   \pos@br={bottomright}  


% \nodeconnect[fromloc]{fromnode}[toloc]{tonode}
\def\nodeconnect{\@ifnextchar [{\@nodeconnect}{\@nodeconnect[b]}}
\def\@nodeconnect[#1]#2{\@ifnextchar [{\@@nodeconnect[#1]{#2}}{\@@nodeconnect[#1]{#2}[t]}}

\def\@@nodeconnect[#1]#2[#3]#4{\pscmd{%
/#2 getnode node\the\csname pos@#1\endcsname \space%
/#4 getnode node\the\csname pos@#3\endcsname\space nodeconnect}}

% \anodeconnect[fromloc]{fromnode}[toloc]{tonode}
\def\anodeconnect{\@ifnextchar [{\@anodeconnect}{\@anodeconnect[b]}}
\def\@anodeconnect[#1]#2{\@ifnextchar [{\@@anodeconnect[#1]{#2}}{\@@anodeconnect[#1]{#2}[t]}}

\def\@@anodeconnect[#1]#2[#3]#4{\pscmd{%
/#2 getnode node\the\csname pos@#1\endcsname \space%
/#4 getnode node\the\csname pos@#3\endcsname\space arrownodeconnect}}


% \nodecurve[fromloc]{fromnode}[toloc]{tonode}{depthfrom}[depthto]

\def\nodecurve{\@ifnextchar [{\@nodecurve}{\@nodecurve[b]}}
\def\@nodecurve[#1]#2{\@ifnextchar [{\@@nodecurve[#1]{#2}}{\@@nodecurve[#1]{#2}[t]}}

\def\@@nodecurve[#1]#2[#3]#4#5{\@ifnextchar [{\@@@nodecurve[#1]{#2}[#3]{#4}{#5}}%
{\@@@nodecurve[#1]{#2}[#3]{#4}{#5}[#5]}}

\def\@@@nodecurve[#1]#2[#3]#4#5[#6]{\@tempdima=#5%
\@tempdimb=#6%
\pscmd{/depth \@int{\the\@tempdimb} \space pt def %
 /#4 \the\csname pos@#3\endcsname cur\space %
 /depth \@int{\the\@tempdima} \space pt def %
 /#2 \the\csname pos@#1\endcsname cur\space %
nodecurve}}

% \anodecurve[fromloc]{fromnode}[toloc]{tonode}{depth}

\def\anodecurve{\@ifnextchar [{\@anodecurve}{\@anodecurve[b]}}
\def\@anodecurve[#1]#2{\@ifnextchar [{\@@anodecurve[#1]{#2}}{\@@anodecurve[#1]{#2}[t]}}


\def\@@anodecurve[#1]#2[#3]#4#5{\@ifnextchar [{\@@@anodecurve[#1]{#2}[#3]{#4}{#5}}%
{\@@@anodecurve[#1]{#2}[#3]{#4}{#5}[#5]}}


\def\@@@anodecurve[#1]#2[#3]#4#5[#6]{\@tempdima=#5%
\@tempdimb=#6%
\pscmd{/depth \@int{\the\@tempdimb} \space pt def %
 /#4 \the\csname pos@#3\endcsname cur\space %
 /depth \@int{\the\@tempdima} \space pt def %
 /#2 \the\csname pos@#1\endcsname cur\space %
arrownodecurve}}


% above is well tested below is not
\newif\iftransparent

\def\nodebox#1{\pscmd{/#1 nodebox}}
\def\nodeoval#1{\pscmd{/#1 nodeoval}}
\def\nodetriangle#1#2{\pscmd{/#1 /#2 nodetriangle}}

% \nodecircle[depth]{nodename}

\def\nodecircle{\@ifnextchar [ {\@nodecircle}{\@nodecircle[0pt]}}

\def\@nodecircle[#1]#2{\@tempdima=#1%
\iftransparent
\pscmd{\@int{\the\@tempdima}\space pt /#2 nodecircletrans}
\else
\pscmd{\@int{\the\@tempdima}\space pt /#2 nodecircle}\fi}


% \barnodeconnect[depth]{fromnode}{tonode}
\def\barnodeconnect{\@ifnextchar[ {\@barnodeconnect}{\@barnodeconnect[5pt]}}

\def\@barnodeconnect[#1]#2#3{\@tempdima=#1 \ifdim\@tempdima<0pt
\pscmd{\@int{\the\@tempdima}\space pt %
/#2  getnode nodebottom /#3 getnode nodebottom barnodeconnect}
\else
\pscmd{\@int{\the\@tempdima}\space pt %
/#2  getnode nodetop /#3 getnode nodetop barnodeconnect}
\fi}

\def\abarnodeconnect{\@ifnextchar[ {\@abarnodeconnect}{\@abarnodeconnect[5pt]}}

\def\@abarnodeconnect[#1]#2#3{\@tempdima=#1 \ifdim\@tempdima<0pt
\pscmd{\@int{\the\@tempdima}\space pt %
/#2  getnode nodebottom /#3 getnode nodebottom arrowbarnodeconnect}
% above replaces the line below.
% /#2  getnode nodebottom /#3 getnode nodebottom abarnodeconnect}
\else
\pscmd{\@int{\the\@tempdima}\space pt %
/#2  getnode nodetop /#3 getnode nodetop arrowbarnodeconnect}
\fi}