[Tex/LaTex] Drawing graphs with multiline labels for vertex/edge

graphstikz-pgf

I have been using tikz-graph to draw graphs representing two-part protocols. Now I'd like to add comments to some nodes of the graph (multiline text, to the side of the vertex).
I'm not sure how to do that. I have been adding labels to vertices and putting them outside with LabelOut, but then I can't do multiline text. This is a toy/minimalistic example:

\documentclass{article}

\usepackage{tikz}
\usetikzlibrary{arrows}
\usepackage{tkz-graph}

\usepackage{graphicx}  
\usepackage[T1]{fontenc}

\begin{document}

\begin{tikzpicture}
  \SetUpEdge[lw = 1.5pt,
             color=black,
             labelstyle = {sloped}]
  \SetVertexNoLabel
  \GraphInit[vstyle=Art]
  \tikzset{EdgeStyle/.style={post}}
  \tikzset{node distance = 6 cm}
  \SetVertexMath

  % Two top symbols, displayed as two invisible
  % vertices with visible labels:
  {\tikzset{VertexStyle/.style = {color=white,text=black}}
    \SetVertexLabel
    \Vertex[L=\alpha]{P}
    \SetVertexLabel
    \Vertex[position={right of=P}, L={\beta}]{X}}

  \tikzset{node distance = 1 cm}
  {\SetVertexLabel
   %%%
   %%% HERE: in the next line the label can't be split in two lines...
   \Vertex[LabelOut,Lpos=180,position={below of=P}, L={the protocol starts here}]{X1}
  }
  \tikzset{node distance = 2 cm}
  \SO(X1){X2}
  \SO(X2){X3}
  \tikzset{node distance = 6 cm}

  \EA(X1){A1}
  \EA(X2){A2}
  \Edge[label={220 ESMTP}](X1)(A1)
  \Edge[label={EHLO client-host}](A1)(X2)
  \Edge[label={250 DSN}](X2)(A2)
  \Edge[label={mail from: email-address}](A2)(X3)
\end{tikzpicture}
\end{document}

What wold be the usual, easy way to do what I'm trying to do?

Best Answer

I'm the author of this package. The good news are the new versions of tkz-graph and tkz-berge will be on the ctan servers this week (i'm working on the docs actually), the bad news are that I modified some macros. I'm not sure to understand exactly what you want but an answer is that you can put TikZ's code inside you code.

Vertices are nodes so you can add multiple labels if you want with the option label= , if you want adding a text you can use the option text width

something like :

  \SO(P){X1}
  \node[text width=2cm,left=1cm] (X1){the protocol starts here};

Another possibility :

\begin{tikzpicture}
{  \SetVertexNoLabel   
   \Vertex[style={label=60:A}]{A}}
 \SO[Lpos=180,
     LabelOut,
     L= {the protocol starts here},
     style={text width=2cm}](A){B}
 \end{tikzpicture}

But there are other ways to do this. You can use label. In your code you used "position" , it's not very fine because it's a problem to use "scale".

In 12 hours, I will upload the new version of tkz-graph. I the new version node distanceis obsolete, now I added an option unit and a macro \tkzGraphUnit=6 instead of `\tikzset{node distance=6cm}.

Related Solutions

[Tex/LaTex] Rotate a node but not its content: the case of the ellipse decoration

The source of the difficulty is that ellipses are constructed in a particular way in TikZ. They are paths that start from the x-axis and proceed counter-clockwise around their centre. The vast majority of the time, the exact parametrisation doesn't matter. You appear to have found the one situation where it does!

In the actual question, you only want to be able to mirror the ellipse, and so draw it starting from the negative x-axis (the title of the question suggests a more flexible approach). That's actually not too hard since we can exploit the symmetry of the ellipse. The key is to provide it with a negative x-radius, since then it will start from the negative x-axis (and proceed clockwise, but we could correct for that by negating the y-radius as well). To do this, we interrupt the call from the node shape to the drawing command and flip the sign of the x-radius. The simplest way to do this is to redefine the \pgfpathellipse macro to do the negation and then call the original macro. The following code does this.

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{decorations,shapes,decorations.markings}
\makeatletter
\let\origpgfpathellipse=\pgfpathellipse
\def\revpgfpathellipse#1#2#3{%
  #2%
  \pgf@xa=-\pgf@x
  \origpgfpathellipse{#1}{\pgfqpoint{\pgf@xa}{0pt}}{#3}}
\makeatother

\tikzset{
  reversed ellipse/.style={
    ellipse,
    reverse the ellipse%
  },
  reverse the ellipse/.code={
    \let\pgfpathellipse=\revpgfpathellipse
  }
}
\begin{document}
\begin{tikzpicture}
\node[ellipse,
  draw,
  postaction={
    decorate,
    decoration={
      markings,
      mark=at position 1 with {
        \arrow[line width=5pt,blue]{>}
      }
    }
  }
] at (0,0) {hello world};

\node[reversed ellipse,
  draw,
  postaction={
    decorate,
    decoration={
      markings,
      mark=at position 1 with {
        \arrow[line width=5pt,blue]{>}
      }
    }
  }
] at (0,-2) {hello world};
\end{tikzpicture}

\end{document}

Here's the result:

rotated ellipse

(the arrow got clipped, but you can see where it lies)

[Tex/LaTex] Package for drawing RDF graphs

As first think I would start to define the style able to represent the vertices; we basically need:

an ellipse;
some size definitions;
drawing the border thicker and setting the fill color brighter with respect to the border;
making the text in white color;
perhaps reduce a bit the size of the text font.

The style definition in TikZ can be done via \tikzset:

\tikzset{vertex style/.style={
    draw=#1,
    thick,
    fill=#1!70,
    text=white,
    ellipse,
    minimum width=2cm,
    minimum height=0.75cm,
    font=\small,
    outer sep=3pt, % the usage of this option will be clear later on
  },
}

Notice two things: this style receives an argument, the color and sets the fill color brighter by mixing the color with white. Secondly, the ellipse shape requires the library:

\usetikzlibrary{shapes.geometric}

Let's now create the first vertex. I would start with the "Righteous Kill" which has most connections departing from.

\documentclass[dvipsnames,png,border=10pt,tikz]{standalone}
\usepackage{tikz}
\usetikzlibrary{shapes.geometric} % required for the ellipse shape
\tikzset{vertex style/.style={
    draw=#1,
    thick,
    fill=#1!70,
    text=white,
    ellipse,
    minimum width=2cm,
    minimum height=0.75cm,
    font=\small,
    outer sep=3pt,
  },
}
\begin{document}
\begin{tikzpicture}
\node[vertex style=Turquoise] (Rk) {Righteous Kill};
\end{tikzpicture}
\end{document}

Beware of the option dvipsnames: it has been necessary to set this within the class options to prevent a possible option clash error since TikZ loads itself xcolor.

The node uses the style defined above setting its color (definition in the xcolor manual), its name (Rk) and its text {Righteous Kill}.

The result:

enter image description here

From now on, I won't display any time the preamble, but rather just the picture code.

Second step is to locate the other nodes. One might exploit lots of possibilities (using GraphViz, using the object-oriented module of PGF and build some custom class - see: Drawing relationships between elements of a database): here I use the positioning library of TikZ. Each vertex, therefore, will be located starting from the position of other vertices by referring to their names.

Notice: since each vertex needs to be connected to another one, the syntax

\node[options] (a) {text a} ... edge[options] node[options]{text conn} (b);

will connect the vertices a and b setting a label to the connection text conn. Extremely useful in this case. Indeed, let's start to add another node:

\begin{tikzpicture}[node distance=2.75cm,>=stealth']
\node[vertex style=Turquoise] (Rk) {Righteous Kill};

\node[vertex style=BurntOrange, above of=Rk,xshift=2em] (BD) {Bryan Dennehy}
 edge [<-,cyan!60!blue] node[text style,above]{starring} (Rk);
\end{tikzpicture}

The options node distance=2.75cm,>=stealth' concern the basic vertex distance and the type of the arrow tip used for the connection. Due to the arrow tip selected, the library arrows should be loaded.

Notice that the connection text requires a style: text style. Its definition is:

\tikzset{
  text style/.style={
    sloped, % the text will be parallel to the connection 
    text=black,
    font=\footnotesize,
    above
  }
}

The location of the new node is done via the options above of=Rk,xshift=2em: the first one sets the position in relation to the name of the previous node we created before, the second one shifts a bit on the right this position.

Result:

enter image description here

Once understood this mechanism, it is possible to locate all the other nodes:

\begin{tikzpicture}[node distance=2.75cm,>=stealth']
\node[vertex style=Turquoise] (Rk) {Righteous Kill};

\node[vertex style=BurntOrange, above of=Rk,xshift=2em] (BD) {Bryan Dennehy}
 edge [<-,cyan!60!blue] node[text style]{starring} (Rk);

\node[vertex style=BurntOrange, right=1.5cm of Rk,yshift=4ex] (AP) {Al Pacino}
 edge [<-,cyan!60!blue] node[text style]{starring} (Rk); 

\node[vertex style=red, below right of=Rk,xshift=2em] (JA) {John Avnet}
 edge [<-,cyan!60!blue] node[text style]{director} (Rk); 

 \node[vertex style=BurntOrange, right=1.5cm of Rk,yshift=-4ex] (RN) {Robert De Niro}
 edge [<-,cyan!60!blue] node[text style]{starring} (Rk); 

\node[vertex style=MidnightBlue, above right of=Rk,xshift=2em] (Dr) {Drama}
 edge [<-,cyan!60!blue] node[text style]{genre} (Rk); 

\node[vertex style=Maroon, below of=Rk,xshift=-2em] (Skf) {Serial Killer Films}
 edge [<-,cyan!60!blue] node[text style]{subject} (Rk);

\node[vertex style=Maroon, below right of=Skf] (Cf) {Crime Films}
 edge [<-,cyan!60!blue] node[text style]{broader} (Skf);
\end{tikzpicture}

enter image description here

Once this task is done, it is possible to start adding the "liquid" background around some vertices.

To place something in background the library backgrounds is of help, as well as the hobby library by Andrew Stacey to draw the smooth curve. Moreover, often some computation are needed, therefore also the library calc should be loaded.

The path definition should be done as follows: starting from the north of the node (Rk), one circumnavigates all possible anchors of the interested nodes to be highlighted. There are some automatic tools, see Hobby path realization in convex hull approach, but they can not be precise and fine tune things as some manual work can do. And, in this case this allows, to achieve a best result.

\begin{pgfonlayer}{background}
\draw[Maroon,fill=Maroon,dashed,fill opacity=0.1](Rk.north) 
to[closed,curve through={(Rk.north west).. (Rk.west) .. (Rk.south west) 
..($(Rk.south west)!0.5!(Skf.north)$) .. (Skf.north     west).. (Skf.west) 
.. (Skf.south west) .. ($(Skf.south)!0.75!(Cf.west)$) .. (Cf.west) 
.. (Cf.south west) .. (Cf.south) .. (Cf.south east) .. (Cf.east) 
.. ($(Cf.north east)!0.65!(Skf.south east)$) .. (Skf.east) 
.. (Skf.north east).. ($(Skf.north)!0.35!(Rk.south east)$) 
.. (Rk.south east) .. (Rk.east)..(Rk.north east)}](Rk.north);
\end{pgfonlayer}

More or less that's the code... but that's the result:

enter image description here

The mysterious option outer sep=3pt allows to not have the "liquid background" too much close to the border shape. And now it's all!

The complete code for reference:

\documentclass[dvipsnames,png,border=10pt,tikz]{standalone}
\usepackage{tikz}
\usetikzlibrary{shapes.geometric} % required for the ellipse shape
\usetikzlibrary{arrows, backgrounds, calc, hobby, positioning}

% this avoides some problem with the hobby implementation
% egreg's code from:
% http://www.guitex.org/home/it/forum/5-tex-e-latex/83195-la-libreria-hobby-tikz-non-funziona-piu#83203
\ExplSyntaxOn
\cs_if_exist:NF \prg_stepwise_function:nnnN { \cs_gset_eq:NN \prg_stepwise_function:nnnN \int_step_function:nnnN }
\cs_if_exist:NF \prg_stepwise_inline:nnnn { \cs_gset_eq:NN \prg_stepwise_inline:nnnn \int_step_inline:nnnn }
\ExplSyntaxOff

\tikzset{vertex style/.style={
    draw=#1,
    thick,
    fill=#1!70,
    text=white,
    ellipse,
    minimum width=2cm,
    minimum height=0.75cm,
    font=\small,
    outer sep=3pt,
  },
  text style/.style={
    sloped,
    text=black,
    font=\footnotesize,
    above
  }
}

\begin{document}
\begin{tikzpicture}[node distance=2.75cm,>=stealth']
\node[vertex style=Turquoise] (Rk) {Righteous Kill};

\node[vertex style=BurntOrange, above of=Rk,xshift=2em] (BD) {Bryan Dennehy}
 edge [<-,cyan!60!blue] node[text style]{starring} (Rk);

\node[vertex style=BurntOrange, right=1.5cm of Rk,yshift=4ex] (AP) {Al Pacino}
 edge [<-,cyan!60!blue] node[text style]{starring} (Rk); 

\node[vertex style=red, below right of=Rk,xshift=2em] (JA) {John Avnet}
 edge [<-,cyan!60!blue] node[text style]{director} (Rk); 

 \node[vertex style=BurntOrange, right=1.5cm of Rk,yshift=-4ex] (RN) {Robert De Niro}
 edge [<-,cyan!60!blue] node[text style]{starring} (Rk); 

\node[vertex style=MidnightBlue, above right of=Rk,xshift=2em] (Dr) {Drama}
 edge [<-,cyan!60!blue] node[text style]{genre} (Rk); 

\node[vertex style=Maroon, below of=Rk,xshift=-2em] (Skf) {Serial Killer Films}
 edge [<-,cyan!60!blue] node[text style]{subject} (Rk);

\node[vertex style=Maroon, below right of=Skf] (Cf) {Crime Films}
 edge [<-,cyan!60!blue] node[text style]{broader} (Skf);

\begin{pgfonlayer}{background}
\draw[Maroon,fill=Maroon,dashed,fill opacity=0.1](Rk.north) 
to[closed,curve through={(Rk.north west).. (Rk.west) .. (Rk.south west) 
..($(Rk.south west)!0.5!(Skf.north)$) .. (Skf.north     west).. (Skf.west) 
.. (Skf.south west) .. ($(Skf.south)!0.75!(Cf.west)$) .. (Cf.west) 
.. (Cf.south west) .. (Cf.south) .. (Cf.south east) .. (Cf.east) 
.. ($(Cf.north east)!0.65!(Skf.south east)$) .. (Skf.east) 
.. (Skf.north east).. ($(Skf.north)!0.35!(Rk.south east)$) 
.. (Rk.south east) .. (Rk.east)..(Rk.north east)}](Rk.north);
\end{pgfonlayer}

\end{tikzpicture}
\end{document}

Best Answer

Related Solutions

[Tex/LaTex] Rotate a node but not its content: the case of the ellipse decoration

[Tex/LaTex] Package for drawing RDF graphs

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