Cannot Show Tranparent Background Overlay

Hey all,

Recently, I built a Qt overlay GUI that has a transparent background. All components are shown while the background of the window is transparent, so videos running behind GUI can be seen.

This GUI works well on PC (Ubuntu 18.04), but becomes complete transparent on TX2, which means that the window is transparent but all components are gone. I tried to set the background semi-transparent and got the same result.

I found that “NVIDIA Jetson Linux Developer Guide: Window Systems" said: X window system does not support alpha blending. It seems that window manager on TX2 doesn’t support translucency directly, but my window doesn’t become black like some other cases.

Does anyone have solution or opinion that can help me get translucency work on TX2?

Thanks in advance.

We don’t have experience on Qt. But are you still using X as your window manager? I think you can leverage DRM-KMS which has more capabilities for rendering. Is your Qt able to use DRM as backend?

I’ve tried this on old Qt before. Not sure if this can help you or not.

Thanks for your response. I tried to check the backend of my Qt GUI. And found out that “QQuickWindow::setSceneGraphBackend(QSGRendererInterface::Software);” helps me solve this problem.

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