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Transparency of mainwindow using EGLFS

  • Hi,

    I'm currentlty trying to developp an application that uses two framebuffer of my imx6 based board. The first one is used to display a gstreamer video while the second will be use to add some action buttons (stop, play for example).

    I'm facing a problem that is :
    When I launch the gstreamer on /dev/fb0 (background) and then launch the qt application on /dev/fb1 (foreground) I would like to set a region of the Qt application (bases on a MainWindow designed with QtDesigner) transparency. But I'm not able to set it work. I try with :

    QRegion maskedRegion(0, 0, 1280, 800);

    But still not work, there is always a default transparency ...
    I suspect that the framebuffers have already their own alpha layer but I don't know how to progress...

  • @VincentB


    I am also facing the same issue and came across to your post.
    I thought to check with you whether you got some solution for this.

    In my current application also I am also using two Framebuffer, fb0 for drawing waveform via directly updating the pixel (this is not a Qt Application) and fb1 for Qt Application.

    Expected behavior : When any Qt Window or dialog is active then overlapped area show not show the fb0 content it should be only Qt application.

    Actual behavior : even if my Qt dialog is active the overlapped area also shows the drawing content.

    Any kind of pointer/info will be really a great help.
    Also if you know how to solve this with using single buffer only.

  • These configurations works to me


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