% ecltree.sty (C) hideki isozaki Nov. 12, 1990
%
% In this style file, I intentionally didn't use ordinary 
% terms such as \tree, \subtree, \leaf etc.
% because I will use different tree macros in one file.
%
% This macro needs epic.sty
% Confirm your epic.sty does not contain \makeatother at EOF.

\makeatletter
\typeout{ECL Tree graph macro by isozaki, Nov. 12, 1990}

% Ignore End Of Line

\endlinechar=-1\relax

% Dimensions and Boxes : See below

\newdimen\@BundleWidth
\newdimen\@BundleDepth
\newdimen\@BundleHeight
\newbox\@NodeBox
\newdimen\GapDepth
\GapDepth=15\p@
\newdimen\GapWidth
\GapWidth=4\p@
\newdimen\EdgeLabelSep
\EdgeLabelSep=7\p@

%
%          ---------------                          -
%          | \@TopLabel  |                          |
%          ---------------         -                |
%     (\@SupportX,\@SupportY)      |                |
%              /   \               |                |
%             /     \              |                |
%            /       \             | \GapDepth      | \@BundleHeight
%           /         \            |                |
%          /           \           |                |
%(\@HandleX,0)          \          |                |
% --------------   --------------  -                -
% | \@NodeBox  |   | \@NodeBox  |  | \@BundleDepth  
% |            |   --------------  |                
% --------------                   -                
%              |---|
%            \GapWidth
%
% |-----------------------------|
%           \@PicWidth

%
% The main environment to make a (sub)tree: bundle
% \begin{bundle} \chunk_1 \chunk_2 ... \chunk_n \end{bundle}
%
\def\bundle#1{\leavevmode\hbox\bgroup
	\endlinechar=-1
	\def\@TopLabel{#1}
	\def\@HandleList{}
	\def\@EdgeLabels{}
	\edef\@EdgeLabelsY{\expandafter\@RemoveDim\the\EdgeLabelSep}
	\unitlength=\p@
	\@BundleWidth=\z@
	\@BundleHeight=\z@
	\@BundleDepth=\z@
	\ignorespaces}

\def\endbundle{
	\advance\@BundleWidth by -\GapWidth
	\hskip-\GapWidth
	\setbox\@NodeBox=\hbox{\vbox{\null\@TopLabel}}
	\advance\@BundleHeight by \GapDepth
	\advance\@BundleHeight by \ht\@NodeBox
	\advance\@BundleHeight by \dp\@NodeBox
	\vrule\@height\@BundleHeight\@width\z@\@depth\@BundleDepth
	\edef\@SupportY{\expandafter\@RemoveDim\the\GapDepth}
	\edef\@SupportX{\expandafter\@RemoveDim\the\@BundleWidth}
	\setbox\@NodeBox=\hbox to \z@{\hss\@TopLabel\hss}
	\hskip-\@BundleWidth
	\edef\@EdgeLabels{\@EdgeLabels{}}
	\edef\@PicWidth{\expandafter\@RemoveDim\the\@BundleWidth}
	\@BundleWidth=0.5\@BundleWidth
	\edef\@SupportX{\expandafter\@RemoveDim\the\@BundleWidth}
	\@DrawBundle}


\def\@DrawBundle{
	\begin{picture}(\@PicWidth,0)(0,0)
	\edef\@HandleList{\expandafter\@cdr\@HandleList\@nil}
	\@for\@HandleX:=\@HandleList\do{
		\@DrawLine(\@SupportX,\@SupportY)(\@HandleX,0)
		\put(\@HandleX,\@EdgeLabelsY){
			\makebox(0,0){\expandafter\@car\@EdgeLabels\@nil}}
		\edef\@EdgeLabels{\expandafter\@cdr\@EdgeLabels\@nil}}
	\put(\@SupportX,\@SupportY){\raise\dp\@NodeBox\box\@NodeBox}
	\end{picture}\egroup}


%
%  \chunk[#1]{#2} means a leaf or a subtree.
%   #1  ... Label for the edge which connects the leaf or the subtree
%           with its parent node. (optional argument)
%   #2  ... Label for the leaf or the subtree 
%

\def\chunk{\@ifnextchar[{\@chunk}{\@chunk[]}}

\def\@chunk[#1]#2{\edef\@EdgeLabels{\@EdgeLabels{#1}}
	\setbox\@NodeBox=\vtop{\null\hbox{#2}}
	\advance\@BundleWidth by 0.5\wd\@NodeBox
	\ifnum\@BundleDepth<\dp\@NodeBox
		\@BundleDepth=\dp\@NodeBox\fi
	\edef\@HandleList{\@HandleList,
		\expandafter\@RemoveDim\the\@BundleWidth}
	\advance\@BundleWidth by 0.5\wd\@NodeBox
	\advance\@BundleWidth by \GapWidth
	\box\@NodeBox\hskip\GapWidth
	\ignorespaces}

%  To change line attribute
%  ex.
%  \drawwith{\path}        ... efficient solid line defined by eepic.sty
%  \drawwith{\dashline{2}} 

\def\drawwith#1{\def\@DrawLine{#1}}

% Default
\drawwith{\drawline}

%  Ordinary catcode for p and t is 11
%  Application of \the to dimen generates text such as 1.0pt.
%  This pt's catcode is 12.

{\catcode`\p=12 \catcode`\t=12
\gdef\@RemoveDim#1pt{#1}}

% Restore original End Of Line

\endlinechar=13\relax

\endinput