Path: utzoo!attcan!uunet!husc6!mailrus!tut.cis.ohio-state.edu!ucbvax!AECLCR.BITNET!01659
From: 01659@AECLCR.BITNET (Greg Csullog)
Newsgroups: comp.sys.atari.st
Subject: GEM Objects
Message-ID: <8903130457.AA22507@ucbvax.Berkeley.EDU>
Date: 13 Mar 89 04:57:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 22

In playing around with GEM, I tried replacing the desktop (from
within an application) with a Degas Elite picture by:

1. defining the picture as a BITBLK data structure

2. placing the BITBLK data structure into an object data
   structure where:

     OB_TYPE=23  (G_IMAGE)
     OB_SPEC=pointer to the BITBLK structure

The replacement worked OK, but in object redraws, the mode is
transparent and I cannot see from my documentation how to get
into the replace mode. Windows, accessory images, etc, leave
ghosts on the new desktop.

If I use a GEM object like a G_BOX, the OB_SPEC lets me set
either transparent or replace via the OBJECT COLOR; when I set
replace, redraws eliminate the ghosting.

How would I set redraws to replace mode if I am using a G_IMAGE
object spec? OBJC_DRAW does not have a parameter to set.