A QGraphicsScene is a class from the Qt toolkit that provides a surface for managing a large number of 2D graphical items.
A QGraphicsView is a class from the Qt toolkit which provides a widget for displaying the contents of a QGraphicsScene.
Default necessary scroll
"By default when you scale a qgraphicsscene larger than the qgraphicsview in which it is displayed it will show the necessary scroll bars"
from question "How to resize a QGraphicsView after QGraphicsView::Scale"
"If i set a pixmap to a qgraphicsscene that is larger that the window it will add scrollbars so is it possible to get what is displayed in the qgraphicsview"
from question "Getting the visible area of a QGraphicsScene in QGraphicsView"
"Generaly qgraphicsscene better using with connection qgraphicsview"
from question "Understanding QGraphicsScene in Qt"