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From: dob@inel.GOV (Dave Brooks)
Newsgroups: comp.windows.x
Subject: root-window (DECwindows)
Message-ID: <9103081840.AA09751@mijen.inel.gov>
Date: 8 Mar 91 18:40:42 GMT
Sender: dob@inel.gov
Organization: The Internet
Lines: 56


   From: schwengeler@urz.unibas.ch
   Newsgroups: comp.windows.x
   Date: 6 Mar 91 14:12:49 GMT
   Organization: University of Basel, Switzerland

   Dear knowledgeable X_gurus,

   I'd like to load an X11 bitmap file into the root window on my
   VAXstation 3500 runnung under VMS V5.4-1 and DECwindows.
   I use the program xloadimage which works fine for displaying
   the image in a window. Appearently, DECwindows has over its
   real root window some pseudo-root window which hides everything
   uder it. When using "$ xloadimage -onroot imgae.xbm", the
   image gets loaded correctly, but nothing can be seen until
   logout (from the Session Manager). Then you will see briefly
   the image which was hidden all the time.
   Now I would like to get the image into the pseudo-root or
   else delete the pseudo-root so that the real root window comes
   to front. How do you achieve this? There's surely a way to fiddle
   these windows?

   Any hints appreciated.

					   Yours, Hans Schwengeler
					   schwengeler@urz.unibas.ch

I think i have a better suggestion than the poster who said to use Mwm,
even though i have no particular use for DECwindows.  under separate mail
i'll send you the file vroot.h, which is used to help applications deal
with the presence of the tvtwm window manager (which i use).  it too makes
a "pseudo-root" or virtual root window.  the method used in vroot.h is to
1) get the children of the root window and 2) check each to see if they
contain a certain property, the presence of which marks it as the
pseudo-root (in your context).  

i would do this:  use xlswins to get the window id of the pseudo root.  use
xprop -id 'this window id' to see what unique or distinctive properties it
has.  then modify vroot.h to look for this property (instead of the one it
currently looks for) and include vroot.h in xloadimage, in any of the
source files that use the macros RootWindow or DefaultRootWindow.

i've been in switzerland before; beautiful country.

this should help!  not having access to a decwindows machine, i can't
really help you too much directly.  however, i'm willing to correspond if
you would like assistance.

regards,
dlb
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David L. Brooks
Idaho National Engineering Lab.  INTERNET: dob@INEL.GOV
POB 1625 MS 2603                 Phone: (208) 526-0826
Idaho Falls, Id. 83415		 FAX:   (208) 526-9936
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