Re: X Background Diversions?

[Dennis McMurchy <denismcm@example.com>]

  Looking at Andrew's later posting I just had another idea for you:
Have you looked at the program xearth?
DESCRIPTION
       Xearth sets the X root window to an image of the Earth, as
       seen from your favorite vantage point in space,  correctly
       shaded  for  the  current position of the Sun. By default,
       xearth updates the displayed image every five minutes. The
       time  between updates can be changed with the -wait option
       (see below); updates can be disabled completely  by  using
       the  -once  option  (see  below).   Xearth can also render
       directly into PPM and GIF files instead of drawing in  the
       root window; see the -ppm and -gif options (below).

 This is the description straight out of the man-page.  (Neat little
program by the way).  I seem to remember getting this in source code
form, so you could look at how it was done there.

AUTHOR
         Kirk Johnson <tuna@example.com>
         MIT Laboratory for Computer Science

  Would be the place to inquire.  I found it on sunsite, I think.

Dennis McMurchy, 
Tojinmachi, Fukuoka