bggen(l) MISC. REFERENCE MANUAL PAGES bggen(l)
NAME
bggen - generates colored backgrounds on X11 displays
SYNTAX
bggen [-s size] [-b bits] r1 g1 b1 [r2 g2 b2 ... rn gn bn]
DESCRIPTION
bggen is a program that generates a 1-pixel wide by size-
pixels high vertical stripe. The top of the stripe is in
color (r1,g1,b1), and the bottom of the stripe is in color
(rn,gn,bn). Intermediate colors are interpolated between
these colors. If you specify more than 2 colors, the stripe
passes through all the specified colors, in the order speci-
fied.
The '-b' option specifies the number of significant bits in
the (output) color specifications. It must range between 1
and 8, inclusive. Use values less than 8 (the default) to
limit color use by increasing the color granularity.
Values for 'r', 'g', and 'b' should range between 0 and 255,
inclusive. 0 means 'off', and 255 means 'fully on'.
bggen doesn't actually affect your background directly.
bggen merely generates a small PPM (Portable Pixmap Format)
datafile that XV can read and display.
To use bggen, you should pipe its output into an XV command,
such as: "xv -root -quit -slow24"
The default 'size' is 1024 pixels, which should be as tall
as your display. If your display is taller than that, you
should specify its actual height, otherwise you will get a
bizarre repeating effect, that you probably didn't want.
Note: If you specify small values of '-s', you can get some
neat effects.
TRY THESE
Light Blue to Dark Blue
bggen 100 100 255 50 50 150 | xv -ro -q -s
RGB Rainbow
bggen 0 0 255 0 255 0 255 0 0 | xv -ro -q -s
Green Cylinders
bggen 0 0 0 0 255 0 0 0 0 -s 128 | xv -ro -q -s
Blue to Magenta
bggen 0 0 255 200 0 100 | xv -ro -q -s
Full Rainbow
bggen 0 0 255 0 255 255 0 255 0 255 255 0 255 0 0 | xv -ro -q -s
Repeating Rainbow
bggen 0 0 255 0 255 255 0 255 0 255 255 0 255 0 0
255 0 255 0 0 255 -s 256 | xv -ro -q -s
Amiga Unix Last change: 1
bggen(l) MISC. REFERENCE MANUAL PAGES bggen(l)
It'd probably be nice if the program used some X calls to
determine screen size. It'd also probably be nice if the
program could take colors by 'name', and also by hexadecimal
value.
AUTHOR
John Bradley - bradley@cis.upenn.edu
Amiga Unix Last change: 2