Section: XScreenSaver manual (6)
Updated: 5.40 (12-Aug-2018)
munch - munching squares
] [-foreground color
] [-window] [-root] [-mono] [-install]
] [-delay usecs
] [-xor] [-noxor]
] [-simul number
[-classic | -mismunch | -random]
program performs the munching squares hack. It picks square
size, position, and gravity randomly. It also displays a
creatively broken misimplementation of the classic algorithm.
The munching squares hack consists of drawing Y = X XOR T for a range of X
and T over and over until all the possible combinations of X and T have
come up. It was reportedly discovered by Jackson Wright in 1962 and took 5
instructions of PDP-6 code.
accepts the following options:
Draw on a newly-created window. This is the default.
Draw on the root window.
If on a color display, pretend we're on a monochrome display.
Install a private colormap for the window.
- -visual visual
Specify which visual to use. Legal values are the name of a visual class,
or the id number (decimal or hex) of a specific visual.
- -delay usecs
The delay between steps of the animation, in microseconds. Default: 2500.
Use the XOR drawing function. This is the default.
Don't use the XOR drawing function.
- -clear number
Number of squares to misdraw before clearing the display. Default: 65.
- -simul number
Number of squares to misdraw simultaneously. Default: 5.
Draw classic munching squares only.
Draw "mismunch" only.
Do one or the other.
Display the current frame rate and CPU load.
to get the default host and display number.
to get the name of a resource file that overrides the global resources
stored in the RESOURCE_MANAGER property.
HAKMEM: MIT AI Memo 239, Feb. 29, 1972.
Beeler, M., Gosper, R.W., and Schroeppel, R.
"Unless otherwise stated, all computer programs are in PDP-6/10
- ITEM 146: MUNCHING SQUARES
Another simple display program. It is thought that this was discovered by
Jackson Wright on the RLE PDP-1 circa 1962.
2=X, 3=Y. Try things like 1001002 in data switches. This also does
interesting things with operations other than XOR, and rotations other
than -22. (Try IOR; AND; TSC; FADR; FDV(!); ROT -14, -9, -20, ...)
- ITEM 147 (Schroeppel):
Munching squares is just views of the graph Y = X XOR T for consecutive
values of T = time.
- ITEM 148 (Cohen, Beeler):
A modification to munching squares which reveals them in frozen states
through opening and closing curtains: insert FADR 2,1 before the XOR. Try
data switches =
4000,,4 1000,,2002 2000,,4 0,,1002
(Notation: <left half>,,<right half>)
Also try the FADR after the XOR, switches = 1001,,1.
Copyright 1997 Tim Showalter.
Copyright 2004 Steven Hazel.
Copyright 1992-2008 Jamie Zawinski.
Permission to use, copy, modify, distribute, and sell this software
and its documentation for any purpose is hereby granted without fee,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation. No representations are made about the
suitability of this software for any purpose. It is provided "as is"
without express or implied warranty.