Render directly to screen
Is there a way in Qt to render "directly" to the screen, without first drawing to a QImage and using drawImage? I want to pass a buffer to another thread that just writes to this buffer, knowing nothing about Qt, and have the images show up in my Qt Widget automatically, without triggering an update or doing a drawImage. Something like provided by Windows in with DIBSection.
I have done this once some time ago, (but in Qt4), but cannot find what I did.
Qt::WA_PaintOnScreen can be a starting point.
It could be possible by either accessing your display driver/framebuffer directly or you can have your customized paint engine.
bq. To render outside of Qt's paint system, e.g., if you require native painting primitives, you need to reimplement QWidget::paintEngine().