CDE

NAME

dtscreen - the Common Desktop Environment animated screen savers

SYNOPSIS

dtscreen [−display dsp] [−delay usecs] [−batchcount num] [−saturation value] [−nice nicelevel] [−mode mode]

DESCRIPTION

The dtscreen client supports the following key tasks:

       •Draws an animated image on a provided window IDs

       •Does not assume the size of the provided windows

       •Provides a set of selectable animated images

       •Animation parameters such as nice, speed, number and saturation may be specified

The dtscreen client provides the default screen saver animations for the desktop. When launched, it will query the desktop using the .BDtSaverGetWindows() API for the set for window IDs on which to draw. These window IDs could be the cover windows created by the session manager for session lock, or a window embedded in the style manager’s session lock customization dialog.  Once obtained, the dtscreen client will proceed to draw in these windows using the specified options. If dtscreen cannot obtain the set of window IDs, it will create its own. Usually, the dtscreen client will be invoked directly by the session manager or by the style manager. 

The Session Manager, dtsession, is responsible for locking the session and prompting for a password to unlock. 

The session manager may launch the dtscreen client to provide screen saver animations during session lock. Refer to the session manager specification for resources controlling the launching of screen savers by the session manager. 

The style manager may launch the dtscreen client to provide a preview of a screen saver animation during customization. Refer to the style manager specification for information on how to integrate a screen saver client such as dtscreen into the desktop. 

The dtsession client provides a selectable set of animations. These are:

hopHopalong iterated fractals

lifeConway’s game of life

qixSpinning lines

imageRandom bouncing image

swarmSwarm of bees

rotorRotor

pyroFireworks

flameCosmic flame fractals

wormWiggly worms

randomRandom selection of one of listed animations

OPTIONS

−display dsp
The display on which animations will be drawn.

−delay usecs
The delay option sets the speed at which a mode will operate. It simply sets the number of microseconds to delay between batches of hopalong pixels, qix lines, life generations, image blits, and swarm motions.

−batchcount num
The batchcount option sets the number of things to do per batch to num. In qix mode this refers to the number of lines rendered in the same color. In hop mode this refers to the number of pixels rendered in the same color. In image mode this refers to the number of X logos on the screen at once. In swarm mode this refers to the number of bees. In life mode it means nothing. 

−saturation value
The saturation option sets the saturation of the color ramp used to value. 0 is grayscale, 1 is very rich color and 0.4 is a nice pastel.

−nice nicelevel
The nice option sets the system nicelevel of the dtscreen process to nicelevel.

−mode mode
The mode option specifies which animation should be displayed. Values are:

hopHopalong iterated fractals

lifeConway’s game of life

qixSpinning lines

imageRandom bouncing image

swarmSwarm of bees

rotorRotor

pyroFireworks

flameCosmic flame fractals

wormWiggly worms

randomRandom selection of one of listed animations

RETURN VALUE

Exit values are:

0Successful completion

>0Error condition occurred

EXAMPLES

dtscreen -mode swarm

Display the swarm animation. 

RESOURCES

delayThe delay option sets the speed at which a mode will operate. It simply sets the number of microseconds to delay between batches of hopalong pixels, qix lines, life generations, image blits, and swarm motions. 

batchcountThe batchcount option sets the number of things to do per batch to num. In qix mode this refers to the number of lines rendered in the same color. In hop mode this refers to the number of pixels rendered in the same color. In image mode this refers to the number of X logos on the screen at once. In swarm mode this refers to the number of bees. In life mode it means nothing. 

saturationThe saturation option sets the saturation of the color ramp used to value. 0 is grayscale, 1 is very rich color and 0.4 is a nice pastel. 

niceThe nice option sets the system nicelevel of the dtscreen process to nicelevel. 

modeThe mode option specifies which animation should be displayed. Values are:

hopHopalong iterated fractals

lifeConway’s game of life

qixSpinning lines

imageRandom bouncing image

swarmSwarm of bees

rotorRotor

pyroFireworks

flameCosmic flame fractals

wormWiggly worms

randomRandom selection of one of listed animations

SEE ALSO

dtsessionLaunches the dtscreen client during session lock.  Provides resources that can be used to control this event. Locks and unlocks a session. 

dtstyleLaunched the dtscreen client during session lock customization. Provides the methods by which additional screen saver clients may be integrated into the desktop.