\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{arrows,shapes}
\usepackage{dot2texi}
\begin{document}
% Define layers
\pgfdeclarelayer{background}
\pgfdeclarelayer{foreground}
\pgfsetlayers{background,main,foreground}

% The scale option is useful for adjusting spacing between nodes.
% Note that this works best when straight lines are used to connect
% the nodes.
\begin{tikzpicture}[>=latex',scale=0.8]
   % set node style
   \tikzstyle{n} = [draw,shape=circle,minimum size=2em,
                       inner sep=0pt,fill=red!20]
   \begin{dot2tex}[dot,tikz,codeonly,styleonly,options=-s -tmath]
       digraph G  {
           node [style="n"];
           A_1 -> B_1; A_1 -> B_2; A_1 -> B_3;
           B_1 -> C_1; B_1 -> C_2;
           B_2 -> C_2; B_2 -> C_3;
           B_3 -> C_3; B_3 -> C_4;
       }
   \end{dot2tex}
   % annotations
   \node[left=1em] at (C_1.west)  (l3) {Level 3};
   \node at (l3 |- B_1) (l2){Level 2};
   \node at (l3 |- A_1) (l1) {Level 1};
   % Draw lines to separate the levels. First we need to calculate
   % where the middle is.
   \path (l3) -- coordinate (l32) (l2) -- coordinate (l21) (l1);
   \draw[dashed] (C_1 |- l32) -- (l32 -| C_4);
   \draw[dashed] (C_1 |- l21) -- (l21 -| C_4);
   \draw[<->,red] (A_1) to[out=-120,in=90] (C_2);
   % Highlight the A_1 -> B_1 -> C_2 path. Use layers to draw
   % behind everything.
   \begin{pgfonlayer}{background}
       \draw[rounded corners=2em,line width=3em,blue!20,cap=round]
               (A_1.center) -- (B_1.west) -- (C_2.center);
   \end{pgfonlayer}
\end{tikzpicture}
\end{document}

You are viewing proxied material from ftp.icm.edu.pl. The copyright of proxied material belongs to its original authors. Any comments or complaints in relation to proxied material should be directed to the original authors of the content concerned. Please see the disclaimer for more details.