[PyQt] Screenshot with no show

[David Boddie]

On Tue Jun 21 10:40:56 BST 2011, Mads Ipsen wrote:

> I have a GLWidget (OpenGL) based window which is used for displaying
> chemical structures. I would like to use this window to generate
> thumbnails used as icons for the files containing the chemical structures.
>
> I would like to hide this process of icon generation from the user, so
> is there any way that you can
>
>     * Show/display a GLWidget/QWidget in some sort of virtual frame
>       buffer, in such a way that is does NOT appear visual to the user.
>     * Dump the contents of the invisible window into a pixmap.

You probably want to look at the QGLPixelBuffer class and the associated
example (which is only available in C++...) for inspiration:

  http://doc.qt.nokia.com/4.7/qglpixelbuffer.html

David