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  1. Qt
  2. QTBUG-59170

[REG 5.7->5.8] Canvas getImageData doesn't handle High DPI

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    • 0043fab778f2497f644c434a194b5c5eec851819

    Description

      In a Canvas item, calling getImageData on the context2D javascript objet, doesn't return data independent of the screen's DPI.
      It works if the app doesn't call QGuiApplication::setAttribute(Qt::AA_EnableHighDpiScaling);

      It also works in Qt 5.7 and below.
      In 5.8 you have to call ctx.getImageData((mouse.x*Screen.pixelDensity/2 ...etc.
      Reproducible easily on Android and iOS, not on my Windows because it's not high DPI but maybe on a high DPI windows...

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        1. continuous.qml
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        2. main.qml
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        3. QTBUG-59170.tgz
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              sorvig Morten Sørvig
              AlGrenadine Alexandre GRANVAUD
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                Updated:
                Resolved: