jdb26@LOCAL.UUCP (05/18/91)
If you have save_under specified for a popup window and the
contents of the window under the popup changes, what is the
correct behavior for a server when the popup is unmapped?
A) Restore the contents of the window under the popup, thus losing the
changes made while the window was obscured?
B) Recognize the contents were changed and send an expose event to the
window.
OpenWindows 2.0 appears to do (A).
Jeff Bailey | All opinions are my own and do not
Chemical Abstracts Service | necessarily reflect those of my
Columbus, OH 43221 | employer.
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BITNET: jdb26@cas.bitnet |
UUCP: osu-cis!chemabs!jdb26 |nazgul@alphalpha.com (Kee Hinckley) (05/18/91)
In article <9105172046.AA01600@cas.org> jdb26@LOCAL.UUCP writes: >If you have save_under specified for a popup window and the >contents of the window under the popup changes, what is the >correct behavior for a server when the popup is unmapped? > >A) Restore the contents of the window under the popup, thus losing the > changes made while the window was obscured? > >B) Recognize the contents were changed and send an expose event to the > window. > >OpenWindows 2.0 appears to do (A). I'm not entirely sure why this is happening (I'm not explicitly asking for save_unders in my dialogs) but whatever OW2.0 does, it screws up the display. I often see the following: Dialog 1 is mapped on top of a cmdtool. Dialog 2 is mapped on top of Dialog 1. Dialog 1 is unmapped. Dialog 2 is unmapped. The underlying window now is "restored" to have an image of Dialog 1 on it (clipped to where Dialog 2 was of course). -- Alfalfa Software, Inc. | Poste: The EMail for Unix nazgul@alfalfa.com | Send Anything... Anywhere 617/646-7703 (voice/fax) | info@alfalfa.com I'm not sure which upsets me more: that people are so unwilling to accept responsibility for their own actions, or that they are so eager to regulate everyone else's.
gildea@expo.lcs.mit.EDU (Stephen Gildea) (05/21/91)
If you have save_under specified for a popup window and the
contents of the window under the popup changes, what is the
correct behavior for a server when the popup is unmapped?
A) Restore the contents of the window under the popup, thus losing the
changes made while the window was obscured?
B) Recognize the contents were changed and send an expose event to the
window.
There is at least one other option, which the MIT sample server uses:
C) Keep track of the changing contents (as if the obscured window had
backing store) and restore those contents when the popup is
unmapped. No expose events are sent.
Remember, if it truly supports save unders, the server should not be
sending expose events. Thus neither A nor B is a proper solution.
< Stephen
MIT X Consortiummrm@nss1.com (Michael R. Miller) (05/22/91)
In article <1991May18.155243.26271@alphalpha.com> nazgul@alphalpha.com (Kee Hinckley) writes: >In article <9105172046.AA01600@cas.org> jdb26@LOCAL.UUCP writes: >>If you have save_under specified for a popup window and the >>contents of the window under the popup changes, what is the >>correct behavior for a server when the popup is unmapped? Having spent some time inside the server, when a window is only partially exposed and drawing operations would be clipped while save unders are active, the server (should) draw the unexposed graphics op on the pixmap it is keeping to accomplish save unders. I obtained this information by writing and debugging servers for the X11R4 source tree: I'm not able to comment on other versions such as X11R5 as yet. Michael R. Miller uunet!xzaphod!michael
dwig@b11.ingr.com (David Wiggins) (05/22/91)
gildea@expo.lcs.mit.EDU (Stephen Gildea) writes: > If you have save_under specified for a popup window and the > contents of the window under the popup changes, what is the > correct behavior for a server when the popup is unmapped? > A) Restore the contents of the window under the popup, thus losing the > changes made while the window was obscured? > B) Recognize the contents were changed and send an expose event to the > window. >Remember, if it truly supports save unders, the server should not be >sending expose events. Thus neither A nor B is a proper solution. The Protocol says: If save-under is True, the server is advised that when this window is mapped, saving the contents of windows it obscures would be beneficial. I read this to mean that setting save-under was just a hint that the server could ignore at any time. With this interpretation, B does not violate the protocol, and is thus a proper solution. > < Stephen > MIT X Consortium David P. Wiggins Intergraph
Dave.Rosenthal@eng.sun.COM (David Rosenthal) (05/23/91)
> >Remember, if it truly supports save unders, the server should not be > >sending expose events. Thus neither A nor B is a proper solution. > > The Protocol says: > > If save-under is True, the server is advised that when > this window is mapped, saving the contents of windows > it obscures would be beneficial. > > I read this to mean that setting save-under was just a hint that the > server could ignore at any time. With this interpretation, B does not > violate the protocol, and is thus a proper solution. > Correct. Requesting save-under is a hint. It does not prevent the server from sending expose events if it wants to. For example, if the server was short of memory when the save-under window obscured another it might well decide not to do the save-under this time and just send the Expose events. David.