Hello,

I need to take screenshots of windows which are overlapped or not visible (for example those that are on a different virtual desktop). Now, is that generally possible and how could it be done?

I know about the basic tools xwd and import, which do a good job when capturing the whole screen. But I couldn't get xwd to capture an overlapped window in the whole, i.e. the window without the overlapping stuff. Import kind of worked here, but what it did was just bringing the window to the front first and then taking the screenshot. That's not what I need, I need something which can take screenshots of not visible windows.
That is, I need to know how that is achieved with X. So what would help me is either an open source tool which does this screen captureing or some hints how to do this using Xlib (or some other library).

Thank you,
ceo2