NAME
julia - draws spinning, animating julia-set fractals
SYNOPSIS
julia [-display host:display.screen]
[-foreground color] [-background color] [-window]
[-root] [-mono] [-install] [-visual visual] [-ncolors
integer] [-delay microseconds] [-cycles
integer] [-count integer] [-mouse] [-nomouse]
DESCRIPTION
The julia program draws spinning,
animating julia-set fractals.
It uses ifs {w0 = sqrt(x-c), w1 = -sqrt(x-c)} with random
iteration to plot the julia set, and sinusoidially varied
parameters for the set, and plots parameters with a circle.
One thing to note is that count is the depth of the
search tree, so the number of points computed is (2^count)-1. I use
8 or 9 on a dx266 and it looks okay. The sinusoidal variation of
the parameter might not be as interesting as it could, but it still
gives an idea of the effect of the parameter.
OPTIONS
julia 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
- 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.
- -ncolors integer
- How many colors should be used (if possible). Default 200. The
colors used cycle through the hue, making N stops around the color
wheel.
- -cycles integer
- -count integer
- -mouse
- -nomouse
- If -mouse is specified, the control point of the Julia
set will be derived from the position of the mouse in the window.
When the mouse is not in the window, the control point is chosen
the normal way.
ENVIRONMENT
- DISPLAY
- to get the default host and display number.
- XENVIRONMENT
- to get the name of a resource file that overrides the global
resources stored in the RESOURCE_MANAGER property.
SEE ALSO
X(1),
xscreensaver(1),
xlock(1)
COPYRIGHT
Copyright © 1995 by Sean McCullough.
Permission to use, copy, modify, and distribute this software
and its documentation for any purpose and without fee is hereby
granted, provided that the above copyright notice appear in all
copies and that both that copyright notice and this permission
notice appear in supporting documentation.
AUTHOR
Sean McCullough <bankshot@mailhost.nmt.edu>,
1995.
Ability to run standalone or with xscreensaver added by
Jamie Zawinski <jwz@jwz.org>, 10-May-97.