NAME

grav - draws a simple orbital simulation

SYNOPSIS

grav [-display host:display.screen] [-foreground color] [-background color] [-window] [-root] [-mono] [-install] [-visual visual] [-ncolors integer] [-delay microseconds] [-count integer] [-decay] [-no-decay] [-trail] [-no-trail]

[-fps]

DESCRIPTION

The grav program draws a simple orbital simulation

OPTIONS

grav 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 64. The colors are chosen randomly.
-count integer: Default 12.
-decay
-no-decay: Whether orbits should decay.
-trail
-no-trail: Whether the objects should leave trails behind them (makes it look vaguely like a cloud-chamber.
-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.

COPYRIGHT

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

Greg Bowering <gb@pobox.com>, 1993.

Ability to run standalone or with xscreensaver added by Jamie Zawinski <jwz@jwz.org>, 10-May-97.