NAME

       rocks - animation of flying through an asteroid field

SYNOPSIS

       rocks [--display host:display.screen] [--foreground color] [--background color] [--window]
       [--root] [--window-id number][--mono] [--ncolors n] [--install] [--visual visual] [--count
       integer] [--delay usecs] [--speed integer] [--norotate] [--nomove] [-3d] [--fps]

DESCRIPTION

       The  rocks  program  draws  an animation of an asteroid field moving past the observer (or
       vice versa).  Sometimes the observer picks up spin on Z axis.

OPTIONS

       rocks accepts the following options:

       --window
               Draw on a newly-created window.  This is the default.

       --root  Draw on the root window.

       --window-id number
               Draw on the specified window.

       --mono  Make all the rocks the same color.

       --ncolors colors
               How many different colors to use.  Default 5.  Colors are chosen randomly.

       --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.

       --count integer
               Maximum number of rocks to draw on the screen at once.  Default 100.

       --speed integer
               A measure of the speed with which the observer and the rocks pass each other, from
               1 to 100.  Default 100, meaning ``very  fast.''   If  you're  on  a  slow  display
               connection (the animation looks jerky) then try making this number smaller, and/or
               decreasing the number of rocks.

       --delay microseconds
               Number of microseconds to delay between each frame.  Default 50000, meaning  about
               1/20th second.  Compare and contrast with --speed, above.

       --norotate
               Don't rotate the observer; just fly through the field on the level.

       --nomove
               Don't turn the observer; just fly straight ahead through the field.

       -3d     Do  red/blue  3d separations: if you look at the screen with 3d glasses, the rocks
               will be jumping right out at you.  Oooooh, scaaary!

       --fps   Display the current frame rate and CPU load.

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.

       XSCREENSAVER_WINDOW
               The window ID to use with --root.

SEE ALSO

       X(1), xscreensaver(1)

BUGS

       There should be an option to display doppler shift (a gravity rainbow.)

       Speed of rotation should be settable.

       Default speed of rotation should be relative to forward velocity.

COPYRIGHT

       Copyright © 1992 by Jamie Zawinski.  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.

AUTHOR

       Based on Lisp Machine code copyright 1988 John Nguyen <johnn@hx.lcs.mit.edu>.

       Ported to C and X by Jamie Zawinski <jwz@jwz.org>, 13-aug-92.

       Steering code by Jeremie Petit; 3D code by theiling@coli.uni-sb.de.