[Tex/LaTex] Tikz mindmap with opacity, a different approach to venn diagrams

mindmapstikz-pgftransparencyvenn-diagrams

I need to draw Venn diagrams for some special sets. In these sets I knew for example that the intersection of some of them are empty, so I wanted to draw a special venn diagram that omits those empty intersections.

I made a graph that each vertex is a set or a intersection of sets. Them I deleted vertex with empty intersection. This way I can get the coordinates of each vertex.

Using mindmap I could make a modified venn diagram. But them don't seem quite good enough. The connection between them are small (there is a decoration called "circle connection bar" but I don't know how can I modify the node concept using this).
A simple example bellow of a posibility.

I just wanted some tips on what kind of parameters should I change to make it better looking. Or maybe a complete change around, maybe midmap isn't the best way.

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{mindmap}

\begin{document}

\begin{tikzpicture}[small mindmap,scale=4,opacity=0.4]
\coordinate (A)   at (2.00003,0.882642);
\coordinate (AB)  at (1.49021,1.74189);
\coordinate (AC)  at (1.50998,0.0102365);
\coordinate (ABC) at (1.00055,0.8711);
\coordinate (B)   at (0.490009,1.73215);
\coordinate (BC)  at (0.,0.860431);
\coordinate (C)   at (0.510476,0.);
% The links between the sets.
% In this notation AB means the intersection of A with B.
\path [concept color=red]
    node [concept] at (A) {}
        child  {node [concept] at (AB) {}}
        child  {node [concept] at (AC) {}}
        child  {node [concept] at (ABC) {}};
\path [concept color=blue]
    node [concept] at (B) {}
        child  {node [concept] at (AB) {}}
        child  {node [concept] at (BC) {}}
        child  {node [concept] at (ABC) {}};
\path [concept color=green]
    node [concept] at (C) {}
        child  {node [concept] at (AC) {}}
        child  {node [concept] at (BC) {}}
        child  {node [concept] at (ABC) {}};
% Place the label later, otherwith they got transparent
\path [opacity=1]
    node at (A) {$A$}
    node at (B) {$B$}
    node at (C) {$C$}
    node at (AB) {$A \cap B$}
    node at (AC) {$A \cap C$}
    node at (BC) {$B \cap C$}
    node at (ABC) {$A \cap B \cap C$};
\end{tikzpicture}

\end{document}

Best Answer

How about this: I used hexagonal nodes instead of circles. You just need to set the colors and separation, the connections are automatically computed to be the average color of the nodes they connect. A node can be assigned one of two styles, venn and unvenn. While venn draws the node, unvenn makes it transparent. You don't need to remove the =some color when using unvenn, this parameter is simply not used in the definition of unvenn.

The Code

\documentclass[parskip]{scrartcl}
\usepackage[margin=15mm]{geometry}
\usepackage{tikz}
\usetikzlibrary{shapes}

\pgfdeclarelayer{background layer}
\pgfsetlayers{background layer,main}

\begin{document}

\colorlet{abccolor}{gray!50}
\colorlet{acolor}{red!50!gray}
\colorlet{abco\documentclass[parskip]{scrartcl}
\usepackage[margin=15mm]{geometry}
\usepackage{tikz}
\usetikzlibrary{shapes}

\pgfdeclarelayer{background layer}
\pgfsetlayers{background layer,main}

\begin{document}

\colorlet{abccolor}{gray!50}
\colorlet{acolor}{red!50!gray}
\colorlet{abcolor}{orange!50!gray}
\colorlet{bcolor}{yellow!50!gray}
\colorlet{bccolor}{green!50!gray}
\colorlet{ccolor}{blue!50!gray}
\colorlet{accolor}{violet!50!gray}

\pgfmathsetmacro{\nodescenterseparation}{4}

\begin{tikzpicture}
[   venn/.style={regular polygon, regular polygon sides=6,shape border rotate=30, minimum width=3cm,draw,inner sep=0,fill=#1,draw=#1!70!black,very thick},
    unvenn/.style={regular polygon, regular polygon sides=6,shape border rotate=30, minimum width=3.5cm,opacity=0},
]
    \node[venn=abccolor] at (0,0) (abc) {$A\cap B\cap C$};
    \node[venn=acolor] at (0:\nodescenterseparation) (a) {$A$};
    \node[venn=abcolor] at (60:\nodescenterseparation) (ab) {$A\cap B$};
    \node[venn=bcolor] at (120:\nodescenterseparation) (b) {$B$};
    \node[venn=bccolor] at (180:\nodescenterseparation) (bc) {$B\cap C$};
    \node[venn=ccolor] at (240:\nodescenterseparation) (c) {$C$};
    \node[venn=accolor] at (300:\nodescenterseparation) (ac) {$A\cap C$};

    \begin{pgfonlayer}{background layer}
        \fill[abccolor!50!acolor] (abc.corner 6) -- (abc.center) -- (abc.corner 5) -- (a.corner 3) -- (a.center) -- (a.corner 2) -- cycle;
        \fill[abccolor!50!abcolor] (abc.corner 1) -- (abc.center) -- (abc.corner 6) -- (ab.corner 4) -- (ab.center) -- (ab.corner 3) -- cycle;
        \fill[abccolor!50!bcolor] (abc.corner 2) -- (abc.center) -- (abc.corner 1) -- (b.corner 5) -- (b.center) -- (b.corner 4) -- cycle;
        \fill[abccolor!50!bccolor] (abc.corner 3) -- (abc.center) -- (abc.corner 2) -- (bc.corner 6) -- (bc.center) -- (bc.corner 5) -- cycle;
        \fill[abccolor!50!ccolor] (abc.corner 4) -- (abc.center) -- (abc.corner 3) -- (c.corner 1) -- (c.center) -- (c.corner 6) -- cycle;
        \fill[abccolor!50!accolor] (abc.corner 5) -- (abc.center) -- (abc.corner 4) -- (ac.corner 2) -- (ac.center) -- (ac.corner 1) -- cycle;

        \fill[acolor!50!abcolor] (a.corner 2) -- (a.center) -- (a.corner 1) -- (ab.corner 5) -- (ab.center) -- (ab.corner 4) -- cycle;
        \fill[abcolor!50!bcolor] (ab.corner 3) -- (ab.center) -- (ab.corner 2) -- (b.corner 6) -- (b.center) -- (b.corner 5) -- cycle;
        \fill[bcolor!50!bccolor] (b.corner 4) -- (b.center) -- (b.corner 3) -- (bc.corner 1) -- (bc.center) -- (bc.corner 6) -- cycle;
        \fill[bccolor!50!ccolor] (bc.corner 5) -- (bc.center) -- (bc.corner 4) -- (c.corner 2) -- (c.center) -- (c.corner 1) -- cycle;
        \fill[ccolor!50!accolor] (c.corner 6) -- (c.center) -- (c.corner 5) -- (ac.corner 3) -- (ac.center) -- (ac.corner 2) -- cycle;
        \fill[accolor!50!acolor] (ac.corner 1) -- (ac.center) -- (ac.corner 6) -- (a.corner 4) -- (a.center) -- (a.corner 3) -- cycle;
    \end{pgfonlayer}
\end{tikzpicture}

\end{document}

Result with all sets non-empty

enter image description here

Result with ABC, A and BC empty

\node[unvenn=abccolor] at (0,0) (abc) {$A\cap B\cap C$};
\node[unvenn=acolor] at (0:\nodescenterseparation) (a) {$A$};
\node[venn=abcolor] at (60:\nodescenterseparation) (ab) {$A\cap B$};
\node[venn=bcolor] at (120:\nodescenterseparation) (b) {$B$};
\node[venn=bccolor] at (180:\nodescenterseparation) (bc) {$B\cap C$};
\node[unvenn=ccolor] at (240:\nodescenterseparation) (c) {$C$};
\node[venn=accolor] at (300:\nodescenterseparation) (ac) {$A\cap C$};

enter image description here

Related Solutions

[Tex/LaTex] venn diagrams using tikz

If you are looking to put the figures side by side, you can use several methods. Like a table, or just moving them with a subfloat, or using minipages. The main idea is that you need to wrap your diagrams, and them adjust the alignment of the wrappers.

For example, using subfloat, you can get:

\documentclass{article}

\usepackage{tikz}
\usepackage{subfig}

\begin{document}
% Definition of circles
\def\firstcircle{(0,0) circle (1.5cm)}
\def\secondcircle{(0:2cm) circle (1.5cm)}

\colorlet{circle edge}{blue!50}
\colorlet{circle area}{blue!20}

\tikzset{filled/.style={fill=circle area, draw=circle edge, thick},
outline/.style={draw=circle edge, thick}}

\setlength{\parskip}{5mm}
\begin{figure}
\centering
% Set A and B
\subfloat{%
\begin{tikzpicture}
\begin{scope}
    \clip \firstcircle;
    \fill[filled] \secondcircle;
\end{scope}
\draw[outline] \firstcircle node {$A$};
\draw[outline] \secondcircle node {$B$};
\node[anchor=south] at (current bounding box.north) {$A \cap B$};
\end{tikzpicture}
}
\hfil
%Set A or B but not (A and B) also known as A or B
\subfloat{%
\begin{tikzpicture}
\draw[filled, even odd rule] \firstcircle node {$A$}
                             \secondcircle node{$B$};
\node[anchor=south] at (current bounding box.north) {${(A \cap B)^{C}}$};
\end{tikzpicture}
}
\end{figure}

\end{document}

float-example

And again, you can do the same using a minipage, in which you have to indicate the width.

\documentclass{article}

\usepackage{tikz}

\begin{document}
% Definition of circles
\def\firstcircle{(0,0) circle (1.5cm)}
\def\secondcircle{(0:2cm) circle (1.5cm)}

\colorlet{circle edge}{blue!50}
\colorlet{circle area}{blue!20}

\tikzset{filled/.style={fill=circle area, draw=circle edge, thick},
outline/.style={draw=circle edge, thick}}

\setlength{\parskip}{5mm}
\begin{figure}
\centering
% Set A and B
\begin{minipage}{0.49\textwidth}
\begin{tikzpicture}
\begin{scope}
    \clip \firstcircle;
    \fill[filled] \secondcircle;
\end{scope}
\draw[outline] \firstcircle node {$A$};
\draw[outline] \secondcircle node {$B$};
\node[anchor=south] at (current bounding box.north) {$A \cap B$};
\end{tikzpicture}
\end{minipage}
%Set A or B but not (A and B) also known as A or B
\begin{minipage}{0.49\textwidth}
\begin{tikzpicture}
\draw[filled, even odd rule] \firstcircle node {$A$}
                             \secondcircle node{$B$};
\node[anchor=south] at (current bounding box.north) {${(A \cap B)^{C}}$};
\end{tikzpicture}
\end{minipage}
\end{figure}

\end{document}

minipage-example

[Tex/LaTex] Line up nested tikz enviroments or how to get rid of them

As is explained in How do I draw shapes inside a tikz node? pics can be used for defining new objects. My main problem using pics is how to place where you want because they aren't nodes and positioning them is not so easy.

Following code shows how to define EDFA block.

    EDFA/.pic={
        \begin{scope}[scale=.5]
        \draw (-1,0) coordinate (in) --  (-1,1) -- (1,0) coordinate (out) --  (-1,-1) -- cycle;
        \node[anchor=north,inner sep=2pt] at (0,-1) {$1$};
        \end{scope}

In this case, coordinate (-1,0) will act as west anchor and 1,0 as east. Both point will have an special name for further reference. Every pic is placed according its own origin (0,0). You can use Claudio's answer to Anchoring TiKZ pics for better positioning.

As your example was simple, I'd prefer to star with EDFA and place Source and Sink after it.

\documentclass[]{article}

% tikz
\usepackage{tikz}
\usetikzlibrary{positioning} %relative positioning

\begin{document}

\tikzset{%
    EDFA/.pic={
        \begin{scope}[scale=.5]
        \draw (-1,0) coordinate (in) --  (-1,1) -- (1,0) coordinate (out) --  (-1,-1) -- cycle;
        \node[anchor=north,inner sep=2pt] at (0,-1) {$1$};
        \end{scope}
    }
}

\begin{tikzpicture}[
block/.style={draw},
]

\draw pic (edfa) {EDFA};

\node[block, left=of edfain] (source) {Source};

\node[block, right= of edfaout] (sink) {Sink};

\draw[->] (source) -- (edfain);
\draw[->] (edfaout) -- (sink);

\end{tikzpicture}

\end{document}

I understand that your components are more complex than EDFA because for this particular case an isosceles triangle node with a label will do the work and it can be used as a node and not as a pic:

\documentclass[]{article}

% tikz
\usepackage{tikz}
\usetikzlibrary{positioning} %relative positioning
\usetikzlibrary{shapes.geometric}

\begin{document}

\begin{tikzpicture}[
    block/.style={draw},
    edfa/.style={isosceles triangle, minimum width=1cm, 
         draw, anchor=west, isosceles triangle stretches, 
         minimum height=1cm, label=-80:#1}
]

\node[block] (source) {Source};

\node[edfa=1, right=of source] (edfa) {};

\node[block, right= of edfa] (sink) {Sink};

\draw[->] (source) -- (edfa);
\draw[->] (edfa) -- (sink);

\end{tikzpicture}

\end{document}