Hello,

it seems that QGraphicsPixmapItem did not get the full retina treatment (see also https://bugreports.qt.io/browse/QTBUG-37008).
Here is a visual example where I rendered :

• boundingRect in blue,
• shape in green,
• opaqueArea in yellow
• the actual pixmap is gray

The opaque area & shape are both scaled wrt the pixmap, which in particular causes problem with the mouse events (that is how I noticed the issue).