Time for action – transforming parent items and child items

Have a look at the following code:

QGraphicsScene scene;
QGraphicsRectItem *rectA = new QGraphicsRectItem(0,0,45,45);
QGraphicsRectItem *rectB = new QGraphicsRectItem(0,0,45,45);
QGraphicsRectItem *rectC = new QGraphicsRectItem(0,0,45,45);
QGraphicsRectItem *rectD = new QGraphicsRectItem(0,0,45,45);
rectB->moveBy(50,0);
rectC->moveBy(0,50);
rectD->moveBy(50,50);
QGraphicsItemGroup *group = new QGraphicsItemGroup;
group->addToGroup(rectA);
group->addToGroup(rectB);
group->addToGroup(rectC);
rectD->setGroup(group);
group->setRotation(70);
rectA->setRotation(-25);
rectB->setRotation(-25);
rectC->setRotation(-25);
rectD->setRotation(-25);
scene.addItem(group);

What just happened?

After creating a scene, we create four rectangle items that are arranged in a 2 x 2 matrix. This is done with the calls of the moveBy() function, which interprets the first argument as a shift to the right or left when negative...