[HOW-TO] PyQt5 QGlPicamera2 always windowed

I am trying to use the QGlPicamera2 widget inside a custom widget. Everything works well following the documentation, but as I try to move the implementation inside a custom widget the Preview will be rendered in a new window and I can’t figure out what I am missing.

In this slice of code the timer updates the countdown timer and triggers the switch_mode_and_capture_file() process with the wait() on the camera… It works and the picture was taken, but the preview was opened into a new window.

The custom camera widget (which will be rendered in stacked layout):

class CustomCameraWidget(QtWidgets.QWidget):

    def __init__(self, signals, picam2, *args, **kwargs):
        super(CustomCameraWidget, self).__init__(*args, **kwargs)
        self.picam2 = picam2
        self._countdown = 5
        self._timer = QTimer()
        self._timer.timeout.connect(self.on_timeout)
        self._layout = QVBoxLayout()
        self._layout.setContentsMargins(0, 0, 0, 0)
        self._layout.setSpacing(0)
        layout = QStackedLayout()
        layout.setStackingMode(QStackedLayout.StackingMode.StackAll)
        self.camera_view = QGlPicamera2(self.picam2, width=800, height=600, keep_ar=False)
        self.camera_view.done_signal.connect(self.on_capture_done)
        layout.addWidget(self.camera_view)
        self.countdown_label = QLabel()
        self.countdown_label.setText(f"{self._countdown}")
        layout.addWidget(self.countdown_label)
        self._layout.addLayout(layout)

        buttons_layout = QHBoxLayout()
        self.abort_button = QPushButton("Undo")
        self.abort_button.clicked.connect(self.undo_button_clicked)
        buttons_layout.addWidget(self.abort_button)
        self._layout.addLayout(buttons_layout)
        self.setLayout(self._layout)

An extract of the main:

if __name__ == "__main__":
    picam2 = Picamera2()
    picam2.configure(picam2.create_preview_configuration())

    app = QApplication(sys.argv)
    window = CustomMainWindow( picam2)
    picam2.start()
    window.show()
    app.exec()

Any suggestion or working example?

[davidplowman]

Thanks for the update. I’ll close this issue for now, but we’ll leave it on our list to have another look at GL rendering at some point.

[bud-mo]

Thanks for the help. I leave a note here:

Using QStackedLayout with QGlPicamera2 needs to specify the parent widget to work, but for some reason the GL stream is not rendered anymore. Moving to use QPicamera2 instead of QGlPicamera2 solve this issue but i don’t want to sacrifice the usage of the GPU.

layout =  QStackedLayout(self)

Unfortunately I’m not experienced with OpenGL, Qt nor Python so I can’t investigate more.

For now I changed the design of the App to not use QStackedLayout where the camera needs to be rendered.