File:4squares-12crossings.png

Configuration of four linked squares.

Self-made, declared to be public domain, generated from the following PostScript source:

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306 396 translate/A{96 96 moveto 96 -96 lineto -96
-96 lineto -96 96 lineto closepath stroke}def 0 1
3{/x exch 90 mul 22.5 add def gsave x sin 78 mul x
cos 78 mul translate 0 setgray 24 setlinewidth A 12
setlinewidth x 292.5 eq{.95 0 0 setrgbcolor}{x 22.5
eq{.2 0 1 setrgbcolor}{x 202.5 eq{0 .8 0
setrgbcolor}{.96 .93 0 setrgbcolor}ifelse}ifelse}
ifelse A grestore}for 24 setlinewidth gsave 22.5
sin 78 mul 22.5 cos 78 mul translate
-96 80 moveto 0 -48 rlineto stroke
-80 -96 moveto 48 0 rlineto stroke
15 -96 moveto 48 0 rlineto stroke
.2 0 1 setrgbcolor 12 setlinewidth
-96 81 moveto 0 -50 rlineto stroke
-81 -96 moveto 50 0 rlineto stroke
14 -96 moveto 50 0 rlineto stroke grestore gsave
112.5 sin 78 mul 112.5 cos 78 mul translate
-96 80 moveto 0 -48 rlineto stroke
-96 -10 moveto 0 -48 rlineto stroke
.96 .93 0 setrgbcolor 12 setlinewidth
-96 81 moveto 0 -50 rlineto stroke
-96 -9 moveto 0 -50 rlineto stroke grestore gsave
202.5 sin 78 mul 202.5 cos 78 mul translate
30 96 moveto 48 0 rlineto stroke
0 .8 0 setrgbcolor 12 setlinewidth
29 96 moveto 50 0 rlineto stroke grestore showpage
%EOF