Morellet's Tirets Illusion

Author

Eric W. Weisstein
September 10, 2003

This notebook downloaded from http://mathworld.wolfram.com/notebooks/RecreationalMath/MorelletsTiretsIllusion.nb.

For more information, see Eric's MathWorld entry http://mathworld.wolfram.com/MorelletsTiretsIllusion.html.

©2005 Wolfram Research, Inc. except for portions noted otherwise

Figure

rot[t_]:={{Cos[t],Sin[t]},{-Sin[t],Cos[t]}}

SquareGrid[{x_,y_},a_:0,z_:{0,0}]:={Line[(z+rot[a].#)&/@{{-y,#},{y,#}}]&/@Range[-x,x],
Line[(z+rot[a]).#&/@{{#,-x},{#,x}}]&/@Range[-y,y]}

Show[Graphics[{
SquareGrid[{30,30}],
SquareGrid[{30,30},.2],
SquareGrid[{30,30},-.2],
SquareGrid[{30,30},.4],
SquareGrid[{30,30},-.4]
}],AspectRatio->Automatic]