petri - simulates mold growing in a petri dish
petri [-display host:display.screen] [-foreground color] [-background
color] [-window] [-root] [-mono] [-install] [-visual visual] [-delay
microseconds] [-size integer] [-mem-throttle amount] [-count integer]
[-originalcolors] [-diaglim real] [-anychan real] [-minorchan real]
[-instantdeathchan real] [-minlifespeed real] [-maxlifespeed real]
[-mindeathspeed real] [-maxdeathspeed real] [-minlifespan integer]
petri simulates mold growing in a petri dish via a state-heavy grid of
automata (vaguely like Conway’s Life, only with much more state per
petri accepts the following options:
-window Draw on a newly-created window. This is the default.
-root Draw on the root window.
-mono If on a color display, pretend we’re on a monochrome display.
Install a private colormap for the window.
Which visual to use. Legal values are the name of a visual
class, or the id number (decimal or hex) of a specific visual.
The interframe delay, in microseconds. Defaults to 10000,
The size of a cell in pixels. Defaults to 4, resource size.
The maximum amount of memory to consume, specified either in
megabytes (suffix "M"), kilobytes (suffix "K"), or bytes (sans
suffix). In order to meet the memory requirement, the cell size
may be increased. Defaults to 22M, resource memThrottle.
How many different varieties of mold to grow (including Black
Death). Defaults to 8, resource count.
If specified, indicates that the colors used should be the
artist’s original choices (a fixed set of primary and secondary
colors). In this case, count must be 8 or less. Defaults to not
specified (i.e., false), resource originalcolors.
The age limit for diagonal growth as a multiplier of orthogonal
growth (range 1..2). 1 means square growth, 1.414 (i.e.,
sqrt(2)) means approximately circular growth, 2 means diamond
growth. Defaults to 1.414, resource diaglim.
The chance (range 0..1) that at each iteration, one or more new
cells will be born. Defaults to 0.0015, resource anychan.
The chance (range 0..1) that, given that new cells will be
born, that only two will be added (hence being a minor cell
birth event). Defaults to 0.5, resource minorchan.
The chance (range 0..1) that, given that death and destruction
will happen, that instead of using Black Death cells, death
will come instantaneously. Defaults to 0.2, resource instant-
The minimum speed for living cells as a fraction of the maximum
possible speed (range 0..1). Defaults to 0.04, resource min-
The maximum speed for living cells as a fraction of the maximum
possible speed (range 0..1). Defaults to 0.13, resource
The minimum speed for Black Death cells as a fraction of the
maximum possible speed (range 0..1). Defaults to 0.42, resource
The maximum speed for Black Death cells as a fraction of the
maximum possible speed (range 0..1). Defaults to 0.46, resource
The minimum lifespan for a colony, in iterations, before Black
Death comes. Defaults to 500, resource minlifespan.
The maximum lifespan for a colony, in iterations, before Black
Death comes. Defaults to 1500, resource maxlifespan.
DISPLAY 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.
There are resource equivalents for each option, noted above.
There are no known bugs in petri as of this writing.
Copyright © 1992-2000 by Dan Bornstein.
Permission to use, copy, modify, distribute, and sell this software and
its documentation for any purpose is hereby granted without fee, pro-
vided 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 suit-
ability of this software for any purpose. It is provided "as is" with-
out express or implied warranty.
Dan Bornstein <email@example.com>, 06-Jul-2000.
X Version 11 06-Jul-2000 XScreenSaver(1)
Man(1) output converted with