fluidballs — the physics of bouncing balls.


fluidballs [-display host:display.screen] [-visual visual] [-window] [-root] [-count number] [-size number] [-gravity number] [-wind number] [-elasticity number] [-delay number] [-nonrandom] [-no-shake] [-fps]


Models the physics of bouncing balls, or of particles in a gas or fluid, depending on the settings. If "Shake Box" is selected, then every now and then, the box will be rotated, changing which direction is down (in order to keep the settled balls in motion.)


-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.
Draw on a newly-created window. This is the default.
Draw on the root window.
-count number
How many balls to display. Default: 300.
-size number
Maximum size of each ball. Default: 25.
-gravity number
Coefficient of gravity. Useful values are < 0.1. Default: 0.01.
-wind number
Wind. Useful values are < 0.1. Default: 0.00.
-elasticity number
Coefficient of elasticity. Useful values are 0.2 to 1.0. Default: 0.97. Lower numbers make less bouncy balls.
-delay number
Per-frame delay, in microseconds. Default: 10000 (0.01 seconds.).
Make all balls be the same size.
Make the balls be random sizes. Default.
-shake | -no-shake
Whether to shake the box if the system seems to have settled down. "Shake" means "change the direction of Down."
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.


Peter Birtles, Jamie Zawinski, and Steven Barker.