The problem is not the coordinates. All the coords are checked to be fine.

The problem is that the calls
translate()
or
centerOn()
didn't move the view...
For example If I put in mouseMoveEvent the call translate(10,10) it will not move the view.
The only call that I have found to move the view is the setSceneRect(), although in documentation it implies that this is not the view piece of the scene, it's the entire scene. In practise it seems to be the viewable rect of the scene.

Am I missing something about the QGraphicsView structure?
When I call translate, rotate etc etc , view is not updated? Why? And how can I do it?

I am at the begining of a project. It's my first use of QGraphicsView/Scene and I have to clear out all the above, before I move on with my work...