gravitywell(6) XScreenSaver manual gravitywell(6)

gravitywell - spaaaaace.

gravitywell [-display host:display.screen] [-visual visual] [-window] [-root] [-delay number] [-speed number] [-resolution number] [-grid-size number] [-count number]

Massive objects distort space in a two dimensional universe.

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.
Draw on a newly-created window. This is the default.
Draw on the root window.
Per-frame delay, in microseconds. Default: 30000 (0.03 seconds).
Animation speed. 2.0 means twice as fast, 0.5 means half as fast.
Density of the underlying universe. Default: 1.0.
Grid Size. Smaller values are more dense. Default: 1.0.
Number of stars. Default: 15.

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.

X(1), xscreensaver(1)

Copyright © 2019 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.

Jamie Zawinski.

6.02 (11-Oct-2021) X Version 11