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  1. Qt
  2. QTBUG-54275

Modifying QGraphicsItem which is not part of a view, causes increasing memory consumption

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    Details

    • Platform/s:
      All
    • Commits:
      1d09b0d1b28eaea17069f7359956640f31ea79c6 (qtbase/5.12, 28.9.2018, 5.12b1)

      Description

      When QGraphicsItem (QGraphicsTextItem in this scenario) is part of a QGraphicsScene, but the scene is not attached to a view, modifying the Item's geometry, contents or anything that requires redraw, increases memory consumption.

      This is caused by line:
      d->updatedRects << rect; (QGraphicsScene.cpp@3198)

      In this specific use-case, the scene may never be attached to a view, so the updatedRects QList is never cleared.

      Steps to reproduce:

      • Run attached sample
      • Observe memory usage
      • EXPECTED: Memory usage does not increase at such high rate (if at all)
      • ACTUAL: Memory usage increases a lot indefinitely

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            • Assignee:
              kleint Friedemann Kleint
              Reporter:
              jussi_witick Jussi Witick
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              Dates

              • Created:
                Updated:
                Resolved:

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