QTextDocument scrolling

[Talei]

Hello,
I want to implement scroll for the QTextDocument and I would like to ask how should I go about doing that?
This is for QGraphicsTextItem so i.e. I can set height for the scene item and scroll text so if document contains many text only small (height) portion of this text is visible.

I know that I need to reimplement paint event for QGraphicsTextItem and in that event I need use QAbstractTextDocumentLayout to actually draw a text setting cliping.
Maybe there is a better / faster approach?

Any idea are more then welcome.