using QOpenGLWidget as viewPort for QGraphicsView in Scene doesn't work?

davecotter

on mac, using the recommended method of installing an OpenGL widget into the QGraphicsView doesn't seem to work.

eg: open the default example code "Video Graphics Item", then at the top of VideoPlayer::VideoPlayer, add this code:

graphicsView->setViewport(new QOpenGLWidget());

when you run and open an HD h.264 movie and play it, you get no video, and a zillion of these in the log:

Failed to activate video surface
QOpenGLFunctions created with non-current context
QPainterVideoSurface: Vertex shader compile error

happens regardless of whether i set the default surface format before startup.

davecotter

does anybody have any clue here?

i'm following the documentation but the doc is apparently wrong :(

SGaist

Hi,

IIRC, the QGraphicsVideoItem already uses OpenGL to do its job so I'd take a look at context sharing. I can't guarantee it will work but it's worth a try.

davecotter

I have already tried that, to no avail. It's unrelated since this is all in the same window anyway.

My question is why does following the method explicitly recommended by the canonical documentation cause errors?

davecotter

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