What do you mean when you say "compositor"? Are you referring to a window system?
Is this something that is possible to implement with the minimal project? What would have to change? I have need a custom platform that encodes the ARGB (proprietary, vendor specific) to the linux framebuffer, but the alpha channel has to actually be correct. How come I can do this without a compositor? QImage bitmap(widget.size(), QImage::Format_ARGB32); bitmap.fill(Qt::transparent); QPainter painter(&bitmap); widget.render(&painter, QPoint(), QRegion(), QWidget::DrawChildren); bitmap.save("file.png"); There must be a way to achieve the same result using a platform plugin. If all else fails, I could create my own thread loop that renders the QWidget with the above code and outputs it to my driver manually, instead of going through the platform plugins, but I would like to support the platform plugin so that I can then switch it out to develop locally using standard Qt platforms (X11, etc). On Fri, Apr 17, 2015 at 10:32 AM, Agocs Laszlo < laszlo.ag...@theqtcompany.com> wrote: > You do have alpha because the minimal's backingstore uses > ARGB32_Premultiplied for the backing QImage. > > What you do not have is setWindowOpacity(). You would need to implement > QPlatformWindow::setOpacity() for that, but that is not possible with > minimal since there is no compositor that could apply the opacity to the > window contents during the composition step. > > Best regards, > Laszlo > > From: Paul Knopf <theonlylawisl...@gmail.com> > Date: Friday 17 April 2015 16:20 > To: "development@qt-project.org" <development@qt-project.org> > Subject: [Development] Qt 'minimal' platform no rendering alpha/opacity. > > I am testing the 'minimal' platform (mine is based off of it), and it > seems that is doesn't render the alpha channel (setting opacity). > > Here is a gist <https://gist.github.com/anonymous/544e84fbcde5022a6878> of > my main function testing the opacity. > > The saved images seems to have a tan background and no transparency. > > Any ideas on how to get the alpha channel represented in the platform > backing store? > > -- > Thanks! > > ~Paul > -- Thanks! ~Paul
_______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development