XWindows - how capture window ?

[Nadav Har'El]

On Thu, Mar 04, 2010, Erez D wrote about "Re: XWindows - how capture window ?":
> composite window managers (i.e. compiz, baryl) work by drawing the original
> window off screen, then read it as a 2D picture, and render it back to the
> screen with certain effects.
> So i know it is possible to grab an off screen window. I do not know however
> how to make it off screen.

This is done using the "Composite" extension. See
http://www.freedesktop.org/wiki/Software/CompositeExt

But please note that all these "extensions", as their title implies, are
not available in every installation of X. The "right way" to use them is
to use them when they're available, but fall back to some slower or uglier
alternative when they aren't.

> There is an X Extension called XDamage, which reports changes on the window
> so you do not have to poll it for changes. These window managers use it.

Right. http://www.freedesktop.org/wiki/Software/XDamage


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Nadav Har'El                        |        Sunday, Mar  7 2010, 21 Adar 5770
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