Add itemToScene transformation to QQuickItem as property

Dear Qt Developers,

i am developer of a larger system with QML and i found rough edges, I will post suggestions as my time allows:

In scene graphs system, as found in games or even the older GraphicsFramework it is common to access the localToScene transformation of an item (aka world orientation), that is position, rotation relative to common reference point (world coordinates) - not so in QtQuick. Here it is not exposed from internal rendering scenegraph. Why ?

Common use case:

Wiring of two items/subitems with spline "cables" requires to track the world position of that item. Ofc. mapToItem function exists, but they lack a signal, when the hierarchy changes.

Suggestion: expose transformation to QML/C++, post transformationChanged signal, when hierarchy was updated.

Current workaround: Install listeners in all parent items of the one being tracked -> cumbersome, not performant.