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Thread: need to draw on pixmaps outside of the gui thread

  1. #1
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    Default need to draw on pixmaps outside of the gui thread

    I need to perform some drawing outside of the main thread (and event loop) and of course I am getting the warning that this can lead to unpredictable behavior.

    Predictably, I occasionally hit an assertion inside Qt.

    I know it's not recommended, but is there a way to lock/synchronize the painting mechanism so that my thread does not interfere with the event loop painting ?

  2. #2
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    Default Re: need to draw on pixmaps outside of the gui thread

    You can draw on QImage in non-GUI thread but not on QPixmap.

  3. #3
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    Default Re: need to draw on pixmaps outside of the gui thread

    True. I wasn't sure if I can initialize the QImage so it matches my display, but it turned out not to be a problem. I can do all my prep work in a worker thread. Dzieki Kolego!

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