Thanks Methedrine, so that gets rid of my boundingRect() calls, but I had discounted this approach because it also kills the repaint function for QGraphicItem objects that I've called .update() on.

I thought I might be able to apply the scene.invalidate() functions, but I still have to call QGraphicsScene.update() after each to get graphics updates, which ends up calling .boundingRect the same absurd number of times as when ViewportUpdate is on.

Is there another way to update just a single QRectF when indexing and viewportUpdate are both turned off?

Thanks,

Deacon