thank you guys for the attention and the support, and sorry if i wasn't able to provide a clear question.
My program should scroll in a full screen window a very large QTextDocument, about 5 lines in the same moment. I've tried several ways to perform the animation and render the text, but I wasn't able to obtain a real smooth and flicker-free animation.
In your opinion, which is the best way to do that? I followed the Animation tutorial and read articles about QT Graphics View Framework, but I didn't find the answer.