Ok so here is some code I wrote to get started:
Qt Code: 
  1. scene = QGraphicsScene(0,0,100,100);
  2. ui->view->addScene(scene);
  3. QGraphicsRectItem *rect = new QGraphicsRectItem(0,0,50,50);
  4. scene->addItem(rect);
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The other parts of the code are cosmetics. But can't, even though I've read the help, understand the relationship between the dimensions and where the things appear drawn in the QGraphicsView.

The rectagle appears not in the middle of the screen, it's like one of the corners is in the middle of the screen, which makes no sense to me with the definition of the scene up above. What's more the size of the rectangle should be of about half the widget in both height and width and it's much smaller than that.

Can any one explain this to me? or tell me where I can find a example simple enough that explains this? Most of the examples I find are complex enough that I can't find a simple piece of explained code that says "This Item is drawn here with this size with respect to the scene".

Thanks for any help.