This example shows how to add a glass to magnify a special part of a pictures. It makes use of the new spy library, so you'll need a recent TikZ version [1] to compile it.
It was created by Dennis Heidsiek [2], based on the example [3], inspired by a sketch in [4].
- [1] http://www.texample.net/tikz/builds/
- [2] http://www.google.com/profiles/Dennis.Heidsiek
- [3] http://www.texample.net/tikz/examples/venn-diagram/
- [4] http://wiki.the-big-bang-theory.com/wiki/Psychic_Vortex

Edit and compile if you like:
% Venn diagram with magnifier% Author: Dennis Heidsiek\documentclass{minimal}\usepackage{tikz}\usetikzlibrary{spy}\usepackage[active,tightpage]{preview}\PreviewEnvironment{tikzpicture}\begin{document}\pagestyle{empty}% First, we define three circles:\def\firstcircle{(-2,0) circle (2.4)}\def\secondcircle{(2,0) circle (2.4)}\pgfmathparse{-(2.4^2-2^2)^0.5} % by pythagoras\let\h\pgfmathresult % shortcut for further use\def\thirdcircle{(0,\h) circle (0.2cm)}\begin{tikzpicture}% Let's draw the scene (to magnify):\begin{scope}[spy using outlines={magnification=16, size=8cm, connect spies, rounded corners}]% the boarder:\draw[thick, rounded corners] (-5,-4) rectangle (5,4);\draw (0,3.3) node[scale=2] {the universe of all jobs};% The transparency:\begin{scope}[fill opacity=0.5]\fill[red] \firstcircle;\fill[green] \secondcircle;\fill[blue] \thirdcircle;\end{scope}% letterings and missing pieces:\draw[align=center] \firstcircle node {what you\\would like\\to do};\draw[align=center] \secondcircle node {what you\\are able\\to do};\draw \thirdcircle
Click to download: venn-diagram-with-magnifier.tex • venn-diagram-with-magnifier.pdf
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