xscreensaver(1)
NAME
attraction - interactions of opposing forces
SYNOPSIS
attraction [-display host:display.screen] [-foreground color] [-background color] [-window] [-root] [-mono] [-install] [-visual visual] [-points int] [-threshold int] [-mode balls | lines | polygons | splines | filled-splines | tails ] [-size int] [-segments int] [-delay usecs] [-color-shift int] [-radius int] [-vx int] [-vy int] [-glow] [-noglow] [-orbit] [-viscosity float] [-mouse] [-no-mouse] [-mouse-size] [-walls] [-nowalls] [-maxspeed] [-nomaxspeed] [-correct-bounce] [-fast-bounce]
DESCRIPTION
The attraction program has several visually different
modes of operation, all of which are based on the interac
tions of a set of control points which attract each other
up to a certain distance, and then begin to repel each
other. The attraction/repulsion is proportional to the
distance between any two particles.
OPTIONS
attraction accepts the following options:
- ArrayGive it a few seconds to settle down into a stable
clump, and then move the mouse through it to make
"waves". - -mouse This will cause the mouse to be considered a con
trol point; it will not be drawn, but it will
influence the other points, so you can wave the
mouse and influence the images being created. - -no-mouse
Turns off -mouse. - -mouse-size integer
In -mouse mode, this sets the mass of the mouse (analagously to the -size parameter.) - -nowalls
This will cause the balls to continue on past the
edge of the screen or window. They will still be
kept track of and can come back. - -walls This will cause the balls to bounce when they get
to the edge of the screen or window. This is the
default behavior. - -maxspeed
Imposes a maximum speed (default). If a ball ends
up going faster than this, it will be treated as
though there were .9 viscosity until it is under
the limit. This stops the balls from continually
accelerating (which they have a tendancy to do),
but also causes balls moving very fast to tend to
clump in the lower right corner. - -nomaxspeed
If this is specified, no maximum speed is set for
the balls. - -fast-bounce
Uses the old, simple bouncing algorithm (default).
This simply moves any ball that is out of bounds
back to a wall and reverses its velocity. This
works fine for most cases, but under some circum
stances, the simplification can lead to annoying
effects. - -correct-bounce
Uses a more intelligent bouncing algorithm. This
method actually reflects the balls off the walls
until they are within bounds. This can be slow if
balls are bouncing a whole lot, perhaps because of
-nomaxspeed. - -graphmode none | x | y | both | speed
For "x", "y", and "both", displays the given
velocities of each ball as a bar graph in the same
window as the balls. For "speed", displays the
total speed of each ball. Default is "none".
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_MAN
AGER property.
SEE ALSO
COPYRIGHT
Copyright © 1992, 1993, 1997 by Jamie Zawinski. Permis
sion to use, copy, modify, distribute, and sell this soft
ware 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 pro
vided "as is" without express or implied warranty.
AUTHOR
Jamie Zawinski <jwz@jwz.org>, 13-aug-92.
Viscosity and mouse support by Philip Edward Cutone, III.
- Walls, speed limit options, new bouncing, graphs, and tail
mode fix by Matthew Strait. 31 March 2001