<_description>
A quasicrystal is a structure that is ordered but aperiodic.
Two-dimensional quasicrystals can be generated by adding a set of
planes where x is the sine of y. Different complex aperiodic plane
tilings are produced depending on the period, position, and rotation
of the component planes, and whether the rotation of the planes is
evenly distributed around the circle (the "symmetry" option, above)
or random.
See also the "RD-Bomb", "CWaves" and "Penrose" screen savers.
https://en.wikipedia.org/wiki/Quasicrystal
Written by Jamie Zawinski; 2013.