QGraphicsPixmapItem::setScale puts image pixels at inconsistant positions

When zooming on an image using QGraphicsPixmapItem::setScale, pixels are jumping around. This can be seen clearly at big zoom factors. See also question on Github.

I am attaching a standalone .cpp file where the zoom factor is controlled with the mouse wheel.

Interestingly, as discussed on Github, when using SmoothPixmapTransform, the pixel positions remain stable. However the image is then bilinearly interpolated, which is undesirable in my case.

This bug may or may not be related to bug QTBUG-60782.