The image that it manipulates will be grabbed from the portion of the screen underlying the window, or from the system's video input, or from a random file on disk, as indicated by the grabDesktopImages, grabVideoFrames, and chooseRandomImages options in the ~/.xscreensaver file; see xscreensaver-demo(1) for more details.

-root

Draw on the root window.

-window

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

-mono

If on a color display, pretend we're on a monochrome display.

-install

Install a private colormap for the window.

-noinstall

Don't 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.

-window-id window-id

Specify which window id to use.

-delay usecs

Specify the delay between subsequent animation frames in microseconds.

-radius pixels

Specify the radius of the distortion zone in pixels.

-speed int

Specify the speed at which the distortion zone moves, where 0 is slow, higher numbers are faster (10 is pretty fast.)

-number int

Specify the number of distortion zones.

-swamp

Instead of letting zones wander around, let small zones pop up like bubbles in a swamp and leave permanent distortion. WARNING: this option uses a colossal amount of memory: keep the -radius small when using -swamp.

-bounce

Let zones wander around and bounce off the window border. This is the default.

-reflect

Mode of distortion that resembles reflection by a cylindrical mirror.

-vortex

Whirlpool-shaped distortion. Way cool.

-magnify

This mode of distortion looks like a magnifying glass.

-blackhole

Suck your pixels beyond the event horizon. Favourite mode of Dr Stephen Hawking.

-slow

Make the zone wander slower.

-shm

Use shared memory extension.

-no-shm

Don't use shared memory extension.

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.