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author | Simon Rettberg | 2018-10-16 10:08:48 +0200 |
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committer | Simon Rettberg | 2018-10-16 10:08:48 +0200 |
commit | d3a98cf6cbc3bd0b9efc570f58e8812c03931c18 (patch) | |
tree | cbddf8e50f35a9c6e878a5bfe3c6d625d99e12ba /hacks/critical.man | |
download | xscreensaver-d3a98cf6cbc3bd0b9efc570f58e8812c03931c18.tar.gz xscreensaver-d3a98cf6cbc3bd0b9efc570f58e8812c03931c18.tar.xz xscreensaver-d3a98cf6cbc3bd0b9efc570f58e8812c03931c18.zip |
Original 5.40
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diff --git a/hacks/critical.man b/hacks/critical.man new file mode 100644 index 0000000..324c116 --- /dev/null +++ b/hacks/critical.man @@ -0,0 +1,94 @@ +.TH XScreenSaver 1 "08 Feb 2000" "X Version 11" +.SH NAME +critical - Draw a system showing self-organizing criticality +.SH SYNOPSIS +.B critical +[\-display \fIhost:display.screen\fP] [\-foreground \fIcolor\fP] [\-background \fIcolor\fP] [\-window] [\-root] [\-mono] [\-install] [\-visual \fIvisual\fP] [\-delay \fIseconds\fP] [\-random \fIboolean\fP] [\-ncolors \fIint\fP] [\-offset \fIint\fP] +[\-fps] +.SH DESCRIPTION +The \fIcritical\fP program displays a self-organizing critical system +that gradually emerges from chaos. + +\fIcritical\fP performs a simulation on a two-dimensional array of +integers. The array is initialized to random values. On each +iteration, it draws a line to the array position with the greatest +value. It then replaces that location and the eight neighboring +locations with randomly-selected values. + +The lines are initially random, but over time a chaotic +self-organizing system evolves: areas of the screen which happen to +have lower values are less likely to be updated to new values, and so +the line tends to avoid those areas. Eventually, the histogram of +changes approaches the power-law curve typical of such systems. + +The simplest documented self-organizing system is the one-dimensional +equivalent of \fIcritical\fP. + +I heard about this algorithm second-hand: apparently there was an +article in \fIScientific American\fP describing it sometime in 1997. +.SH OPTIONS +.I critical +accepts the following options: +.TP 8 +.B \-window +Draw on a newly-created window. This is the default. +.TP 8 +.B \-root +Draw on the root window. +.TP 8 +.B \-mono +If on a color display, pretend we're on a monochrome display. +.TP 8 +.B \-install +Install a private colormap for the window. +.TP 8 +.B \-visual \fIvisual\fP +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. +.TP 8 +.B \-delay \fIusecs\fP +Number of microseconds to wait after drawing each line. +.TP 8 +.B \-random \fIboolean\fP +Whether to use randomly selected colours rather than a cycle around +the colour wheel. +.TP 8 +.B \-offset \fIinteger\fP +The maximum random radius increment to use. +.TP 8 +.B \-ncolors \fIinteger\fP +How many colors should be allocated in the color ramp (note that this +value interacts with \fIoffset\fP.) +.TP 8 +.B \-trail \fIinteger\fP +Length of the trail: between 5 and 100 is nice. +.TP 8 +.B \-fps +Display the current frame rate and CPU load. +.SH ENVIRONMENT +.PP +.TP 8 +.B DISPLAY +to get the default host and display number. +.TP 8 +.B XENVIRONMENT +to get the name of a resource file that overrides the global resources +stored in the RESOURCE_MANAGER property. +.SH SEE ALSO +.BR X (1), +.BR xscreensaver (1) +.BR xscreensaver-command (1) +.BR xscreensaver-demo (1) +.SH COPYRIGHT +Copyright \(co 1998 by Martin Pool. + +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. +.SH AUTHOR +Martin Pool <mbp@humbug.org.au>, 1998-2000. Based in part on the +XScreenSaver code by Jamie Zawinski <jwz@jwz.org>. |