Tim Roberts wrote:
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On Tue, 06 Jul 2004 09:22:27 -0700, Robin Dunn <robin@alldunn.com> wrote:
Interesting. I would have expected this from wxScreenDC or wxWindowDC, but not wxClientDC. Hmmm... digging a little deeper shows that wxWindowDC and wxCLientDC are the same thing on wxGTK, so I guess they are not able to make the distinction there.
I'm surprised you would have expected this. If a window is partially obscured by another window, the pixels underneath the top window simply do not exist (unless you are using X and have backing store enabled, which nobody does). It doesn't matter how you get to the screen, they just aren't there until the region is exposed and the app redraws them.
The ONLY differences between a screen DC, a window DC, and a client DC are the default clipping region and the location of the origin point (0,0). In all other respects, they are identical.
Not quite true. The wxScrenDC gets you whatever is in the screen buffer, regardless of what windows overlap others. My understanding is that wxWindowDc is similar, at least on Windows, except that it is clipped to the window's rect.
--
Robin Dunn
Software Craftsman
http://wxPython.org Java give you jitters? Relax with wxPython!