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From: mouse@lightning.mcrcim.mcgill.EDU (der Mouse)
Newsgroups: comp.windows.x
Subject: Re: PC X servers / backing store
Message-ID: <9103060629.AA07101@lightning.McRCIM.McGill.EDU>
Date: 6 Mar 91 06:29:08 GMT
Sender: daemon@athena.mit.edu (Mr Background)
Organization: The Internet
Lines: 19

>> A problem encountered with both products is that if a graphics
>> window is overlaid ( e.g. by a menu ), the overlaid portion is not
>> restored.  [...backing-store...]

> Just for your information, what you just described above is not
> backing store but save unders.  Backing store works when anything BUT
> a menu which obscures another window is moved so the current window
> is exposed.

Yes and no.  If the saving is controlled by a bit on the menu, it's a
save-under; if by a bit on the window underneath, it's backing-store.
Some (older) implementations actually handle save-unders by turning on
backing-store on obscured windows; this can be catastrophic if the
window underneath is huge and is being clipped by its parent.

					der Mouse

			old: mcgill-vision!mouse
			new: mouse@larry.mcrcim.mcgill.edu