How to apply a clipping mask with TikZ

Question

Without rewriting the code, I want the part where the circles overlap to be transparent so it appears white (or whatever colour is hiding behind the circles).

Graphic designers might refer to this as a clipping mask, alpha compositing, etc.
It's a boolean operation: A XOR B.

\documentclass{standalone}
\usepackage{tikz}

\begin{document}
\begin{tikzpicture}[node distance=3.50em, auto]

%%% define shapes %%%
\tikzstyle{bluecircle} = [draw, circle,
                          fill=blue!20,
                          line width=0.00em, 
                          minimum height=5.00em,
                          text centered]

\tikzstyle{emptycircle} = [draw, circle,
                           fill=none,
                           line width=0.10em,
                           minimum height=5.00em,
                           text centered]

\tikzstyle{emptysquare} = [draw, rectangle,
                           fill=none,
                           line width=0.10em,
                           minimum height=6.00em,
                           text width = 9.00em,
                           text centered]

%%% circle fill %%%   
\node[bluecircle]             (A) {};
\node[bluecircle, right of=A] (B) {};

%%% circle edge %%%    
\node[emptycircle]             (A2) {$A$};
\node[emptycircle, right of=A] (B2) {$B$};

%%% square edge %%%    
\node[emptysquare, xshift=1.75em] (U) {};

\end{tikzpicture}    
\end{document}

If you draw the circles with paths instead of nodes, you can fill the paths according to the even odd rule. Search for that in the manual and I think you’ll find what you’re looking for. — Matthew Leingang, Jul 20 '19 at 17:04
@MatthewLeingang It has to be nodes. Although the nodes do technically draw paths, and it's the paths that need clipping. Surely it's possible. I can't seem to figure it out though. — voices, Jul 20 '19 at 18:07

score 3 · Answer 1 · 2019-07-21T08:58:12.423

Using clip command, the following result can be obtained.

\documentclass{standalone}
\usepackage{tikz}

\begin{document}
\begin{tikzpicture}[node distance=3.50em, auto]

%%% define shapes %%%
\tikzstyle{bluecircle} = [draw, circle,
                          fill=blue!20,
                          line width=0.00em, 
                          minimum height=5.00em,
                          text centered]

\tikzstyle{emptycircle} = [draw, circle,
                           fill=none,
                           line width=0.10em,
                           minimum height=5.00em,
                           text centered]

\tikzstyle{emptysquare} = [draw, rectangle,
                           fill=none,
                           line width=0.10em,
                           minimum height=6.00em,
                           text width = 9.00em,
                           text centered]

%%% circle fill %%%   
\node[bluecircle]             (A) {};
\node[bluecircle, right of=A] (B) {};

%%% circle edge %%%    
%\node[emptycircle]             (A2) {};
%\node[emptycircle, right of=A] (B2) {$B$};

%%% square edge %%%    
\node[emptysquare, xshift=1.75em] (U) {};

\begin{scope}
        \clip (A.center) circle [radius=2.5em];
        \fill[fill=white] (B.center) circle [radius=2.5em];
    \end{scope}
%%% circle edge %%%     
\node[emptycircle]             (A2) {$A$};
\node[emptycircle, right of=A] (B2) {$B$};

\end{tikzpicture}    
\end{document}

How to apply a clipping mask with TikZ

1 Answers1