rocks - Man Page

animation of flying through an asteroid field


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]


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.


rocks accepts the following options:


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


Draw on the root window.

--window-id number

Draw on the specified window.


Make all the rocks the same color.

--ncolors colors

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


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.


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


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


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!


Display the current frame rate and CPU load.



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.


The window ID to use with --root.

See Also

X(1), xscreensaver(1)


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.


Based on Lisp Machine code copyright 1988 John Nguyen <>.

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

Steering code by Jeremie Petit; 3D code by


6.07-4.fc40 (07-Sep-2023) X Version 11 XScreenSaver manual