[comp.sys.hp] X11 server backing store bugs on HP-UX 6.5

lcs@icad.COM (Larry Stone) (01/12/90)

The X server that comes with HP-UX 6.5 claims to support backing store,
and even appears to be using backing store when it is requested, but it
also sends spurious Expose events to the backing-store window.  When an
area of a backing-store window is exposed, it is refreshed very quickly,
with what looks like CopyArea from backing store because it draws lines
and text all at once.  Then, the window gets an Expose event for the
same area, and the client redraws it much more slowly.  The backing
store attribute is WhenMapped, but I've also tried Always.
The behavior is the same when running HPWM, UWM, or no window manager.
When backing store is not requested, the initial backing store refresh
is not observed.

I've run my client and the "xev" event monitor against other servers
which implement backing store correctly, a Visual X-19, and MIT X11R3 on
a Sun.  The window never gets Expose events on those servers until it is
unmapped and mapped, so (as xwininfo also shows) the correct
window attributes are being set.

The hardware is an HP-9000/370 with a TurboSRX and one with a 98549.
Running "what /usr/bin/X11/X" prints:
/usr/bin/X11/X:
	X Window System, Version 11    HP-UX 6.5    A.01    $Revision: 9.1 $
	250.1.2.1   01/27/89 libxd300h.a
	250.1.2.1   01/27/89 libxd300l.a
	250.1.2.1   02/01/89 libxd98550.a
	250.1.2.1   01/27/89 libxd98720.a
	250.1.2.1   01/27/89 libxd98730.a
	250.1.2.1   01/27/89 libsdiutils.a

I have not seen this problem reported in the HP-UX Software Status
Bulletin, and my SE was not able to find out anything about it or any X
updates for 6.5.

Is any solution available from HP?  Upgrading to 7.0 won't do, since this
will need to be installed on 6.5 because of other constraints.  I need
the HP server because it has the extensions to run StarBase on the TSRX,
so using the MIT release is not possible either.

	thanks,

	-- Larry Stone     lcs@icad.com  ..!bu.edu!icad.com!lcs
	   ICAD, Inc.

Compiling R4 on 3/50 (SunOS 4.0.3ng R4 on 3/50 (SunOS 4.0.3)) (01/16/90)

> The X server that comes with HP-UX 6.5 claims to support backing store,
> and even appears to be using backing store when it is requested, but it
> also sends spurious Expose events to the backing-store window.  

> Is any solution available from HP?  Upgrading to 7.0 won't do, since this
> will need to be installed on 6.5 because of other constraints.  I need
> the HP server because it has the extensions to run StarBase on the TSRX,
> so using the MIT release is not possible either.
>	-- Larry Stone     lcs@icad.com  ..!bu.edu!icad.com!lcs

The only fully supported solution is to upgrade to 7.0.  A quick test
shows that the bug is indeed gone from the 7.0 server.  Although not
supported, many people around here were using the 7.0 server (and fonts)
on 6.5 systems.

Harry Phinney

brown@hpfcdq.HP.COM (John Brown) (01/17/90)

Larry -

Just a reminder related to your inquiry . . .

> [ description of backing store problem deleted ]
>
> Is any solution available from HP?  Upgrading to 7.0 won't do, since this
> will need to be installed on 6.5 because of other constraints.  I need
> the HP server because it has the extensions to run StarBase on the TSRX,
> so using the MIT release is not possible either.

If you're planning to use Starbase to gopen() an X11 window on the TSRX,
please be aware that Starbase graphics rendered using the "hp98731" 
(accelerated TSRX) driver will not be preserved by backing store.  Graphics
rendered using the "hp98730" (unaccelerated TSRX) driver will be preserved,
but only if the window depth is 8 bits or less.

This is discussed on pages 4-38 through 4-40 in the "Starbase Programming
with X11" manual.  As far as I know, this functionality has not changed 
for HP-UX 7.0.

John Brown
HP Graphics Technology Division

terminal info wanted info wanted (01/18/90)

> Graphics
> rendered using the "hp98730" (unaccelerated TSRX) driver will be preserved,
> but only if the window depth is 8 bits or less.

> This is discussed on pages 4-38 through 4-40 in the "Starbase Programming
> with X11" manual.  As far as I know, this functionality has not changed 
> for HP-UX 7.0.
> John Brown

John is certainly correct.  I failed to note that the original question
regarded the TSRX.

Harry Phinney