-.TH XScreenSaver 1 "3-dec-92" "X Version 11"
+.TH XScreenSaver 1 "24-Nov-97" "X Version 11"
.SH NAME
slidescreen - permute the screen image like an 8-puzzle
.SH SYNOPSIS
.B \-delay \fImicroseconds\fP
How much of a delay should be introduced between the end of the motion of
one segment and the beginning of the motion of another. Default 1000000,
-which isone second.
+which is one second.
+.SH RESOURCES
+On some systems (currently, only SGIs), this program can, instead of grabbing
+a desktop image, grab a frame of video from an external camera and manipulate
+that instead. The following resources control that.
+.PP
+.TP 8
+.B grabVideoProbability \fR(Float)\fP
+What portion of the time to grab video rather than a screen image,
+between 0.0 and 1.0. Defaults to 0.5, or half the time.
+.TP 8
+.B videoDevice \fR(Integer)\fP
+The number of the default video input device to check first. If unspecified,
+the default camera (from videopanel(1)) will be checked first. After that, all
+other available video input devices will be checked in order.
+
+The first one which produces a non-black image will be used. If all images
+are black, the others will be re-checked a few times before giving up and
+falling back to simply grabbing a desktop image (but note that this takes a
+few seconds, so if you don't actually have any video sources hooked up, you
+should consider turning off video grabbing by setting
+\fBgrabVideoProbability\fP to 0.0.)
+.TP 8
+.B videoGain \fR(Float)\fP
+The amount by which to brighten the grabbed image. This defaults to 2.2.
.SH ENVIRONMENT
.PP
.TP 8
projects / xscreensaver / blobdiff