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From: stroyan@hpfcso.HP.COM (Mike Stroyan)
Newsgroups: comp.sys.hp
Subject: Re: Double buffering in Starbase/X11 combined mode.
Message-ID: <7370204@hpfcso.HP.COM>
Date: 11 Sep 90 18:16:08 GMT
References: <BESHERS.90Sep10165614@division.cs.columbia.edu>
Organization: Hewlett-Packard, Fort Collins, CO, USA
Lines: 19

> Using a Turbo SRX, with X11R4 in combined mode, 12/12 planes
> double buffered, I ran two copies of an animation on the same
> display.  When a process has the input focus, it runs smoothly,
> but the other flickers, because the double buffering is out of sync.
> 
> Fortunately, the manual documents this.  Unfortunately, it seems
> to suggest that there is no cure.  Does anyone know otherwise?

There are a couple of possible cures.  One involves effort and the
other involves money.

You could modify the animation programs to communicate between
each other and synchronize their dbuffer_switch operations.
System V semaphores would make a good communication channel.

You could buy a Turbo VRX, which supports multiple simultaneous
colormaps and double buffering states.

Mike Stroyan, mike_stroyan@fc.hp.com