1petri(6x) XScreenSaver manual petri(6x)
2
6 petri - simulates mold growing in a petri dish
7
9 petri [-display host:display.screen] [-foreground color] [-background
10 color] [-window] [-root] [-mono] [-install] [-visual visual] [-delay
11 microseconds] [-size integer] [-mem-throttle amount] [-count integer]
12 [-originalcolors] [-diaglim real] [-anychan real] [-minorchan real]
13 [-instantdeathchan real] [-minlifespeed real] [-maxlifespeed real]
14 [-mindeathspeed real] [-maxdeathspeed real] [-minlifespan integer]
15 [-maxlifespan integer] [-fps]
16
18 petri simulates mold growing in a petri dish via a state-heavy grid of
19 automata (vaguely like Conway's Life, only with much more state per
20 cell).
21
23 petri accepts the following options:
24 -window Draw on a newly-created window. This is the default.
26 -root Draw on the root window.
28 -mono If on a color display, pretend we're on a monochrome display.
30 -install
32 Install a private colormap for the window.
33 -visual visual
35 Which visual to use. Legal values are the name of a visual
36 class, or the id number (decimal or hex) of a specific visual.
37 -delay microseconds
39 The interframe delay, in microseconds. Defaults to 10000, re‐
40 source delay.
41 -size integer
43 The size of a cell in pixels. Defaults to 4, resource size.
44 -mem-throttle amount
46 The maximum amount of memory to consume, specified either in
47 megabytes (suffix "M"), kilobytes (suffix "K"), or bytes (sans
48 suffix). In order to meet the memory requirement, the cell size
49 may be increased. Defaults to 22M, resource memThrottle.
50 -count integer
52 How many different varieties of mold to grow (including Black
53 Death). Defaults to 8, resource count.
54 -originalcolors
56 If specified, indicates that the colors used should be the
57 artist's original choices (a fixed set of primary and secondary
58 colors). In this case, count must be 8 or less. Defaults to not
59 specified (i.e., false), resource originalcolors.
60 -diaglim real
62 The age limit for diagonal growth as a multiplier of orthogonal
63 growth (range 1..2). 1 means square growth, 1.414 (i.e.,
64 sqrt(2)) means approximately circular growth, 2 means diamond
65 growth. Defaults to 1.414, resource diaglim.
66 -anychan real
68 The chance (range 0..1) that at each iteration, one or more new
69 cells will be born. Defaults to 0.0015, resource anychan.
70 -minorchan real
72 The chance (range 0..1) that, given that new cells will be
73 born, that only two will be added (hence being a minor cell
74 birth event). Defaults to 0.5, resource minorchan.
75 -instantdeathchan real
77 The chance (range 0..1) that, given that death and destruction
78 will happen, that instead of using Black Death cells, death
79 will come instantaneously. Defaults to 0.2, resource instant‐
80 deathchan.
81 -minlifespeed real
83 The minimum speed for living cells as a fraction of the maximum
84 possible speed (range 0..1). Defaults to 0.04, resource min‐
85 lifespeed.
86 -maxlifespeed real
88 The maximum speed for living cells as a fraction of the maximum
89 possible speed (range 0..1). Defaults to 0.13, resource
90 maxlifespeed.
91 -mindeathspeed real
93 The minimum speed for Black Death cells as a fraction of the
94 maximum possible speed (range 0..1). Defaults to 0.42, resource
95 mindeathspeed.
96 -maxdeathspeed real
98 The maximum speed for Black Death cells as a fraction of the
99 maximum possible speed (range 0..1). Defaults to 0.46, resource
100 maxdeathspeed.
101 -minlifespan integer
103 The minimum lifespan for a colony, in iterations, before Black
104 Death comes. Defaults to 500, resource minlifespan.
105 -maxlifespan integer
107 The maximum lifespan for a colony, in iterations, before Black
108 Death comes. Defaults to 1500, resource maxlifespan.
109 -fps Display the current frame rate and CPU load.
111
113 DISPLAY to get the default host and display number.
114 XENVIRONMENT
116 to get the name of a resource file that overrides the global
117 resources stored in the RESOURCE_MANAGER property.
118
120 There are resource equivalents for each option, noted above.
121
123 There are no known bugs in petri as of this writing.
124
126 xscreensaver(1)
127
129 Copyright © 1992-2000 by Dan Bornstein.
130 Permission to use, copy, modify, distribute, and sell this software and
132 its documentation for any purpose is hereby granted without fee, pro‐
133 vided that the above copyright notice appear in all copies and that
134 both that copyright notice and this permission notice appear in sup‐
135 porting documentation. No representations are made about the suitabil‐
136 ity of this software for any purpose. It is provided "as is" without
137 express or implied warranty.
138
140 Dan Bornstein <danfuzz@milk.com>, 06-Jul-2000.
141X Version 11 6.04-1.fc36 (06-Jun-2022) petri(6x)