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.

-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.

-delay microseconds

Slow it down.

-mode mode

The direction in which the image should tend to slide. Legal values are random (meaning pick one), up, left, right, down, upleft, downleft, upright, downright, shuffle (meaning prefer no particular direction), in (meaning move things toward the center), out (meaning move things away from the center), melt (meaning melt straight downward), stretch (meaning stretch the screen downward), and fuzz (meaning go blurry instead of melty).

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.