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Bad Performance under macOS

  • Hello,

    are there still any ways to increase UI performance on macOS? (Qt 5.9.1)

    You can see it already when the main window is enlarged. QListWidget scrolls very slowly. Full-screen operation is no longer working properly.

    HighDPI is activated. Under Windows and Linux, however, everything works smoothly and quickly. Mac does not feel native.

    Sample: The function elidedText in the "paint" event (QAbstractItemDelegate) makes it embarrassed slowly on 4k resolution.

    On a MacBook it runs well, since this has a lower resolution.

    My current conclusion is that Qt applications on Retina 4k / 5k perform very badly.

    Of course, I've also looked at other programs that were made with Qt. SqliteBrowser for example, it jerks also on higher resolution extremely.

    I'm at the moment helpless and afraid that it will remain so. Maybe I overlooked a trick?

    I've noticed that the wider the QListWidget, the slower it gets.

    For better view i have made a video as no listet on YouTube, please take a look :)

    iMac (Retina 5K, 27 Zoll, End 2015)
    3,3 GHz Intel Core i5
    16 GB 1867 MHz DDR3
    512GB SSD HardDrive
    AMD Radeon R9 M395 2048 MB

  • Lifetime Qt Champion


    You should rather bring this to the interest mailing list. You'll find there Qt's macOS port developers/maintainers. This forum is more user oriented.

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