bitblt, how do I save the "real" background of a dialog/window ?!

Hi,

I'm using bitblt to display a bitmap, and a memory DC to avoid flickering. I'm filling the background with the current window-color, this way
I clear the background everytime my bitmap changes its position.

Now, I'd like to "grab" the _real_ background, instead of simply filling the region. How do I "capture" the background (which might include buttons,
text, other controls as well) to use this captured image to restore the background???

Thank you.



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