[Qt-interest] Detecting windowOpacity support

[Dušan Saiko]

Well,

after some searching and experiments,
I have found method QX11Info::isCompositingManagerRunning(),
but this method is using data initialised at qt_init, so no does not 
reflect changes while application is running.

But using the qt src, this is what works:


#include <QX11Info>

#include <X11/Xlib.h>

#include <X11/Xatom.h>


bool SystemInfo::canDrawTransparentWidgets() {

    Display *display = QX11Info::display();

    Atom compositeManagerAtom = XInternAtom(display, "_NET_WM_CM_S0",False);


    return XGetSelectionOwner(display,compositeManagerAtom);

}