Multithreaded multi-MDI app

The app is using multiple windows with each window containing multiple documents. Each document is both graphically as well as computationally intensive and splitting it off to a separate process is a no-go. One top-level window per display, with MDI for individual documents – up to 12 documents is not uncommon on single display setups, many more on multi-display setups with as many as 9+ displays not uncommon either, so lots of documents).

Qt’s Graphics View framework fits perfectly for rendering and interacting with the graphics of a single document, but since there’s typically many documents open at the same time I’m not sure how to proceed as far as multi-threading it. AFAIK QGraphicsScene and friends are not thread-safe, or even reentrant and keeping the app single-threaded is basically a deal-breaker as far as using Qt for the app goes, so any suggestions would be welcome.

EDIT: closed this topic as it’s a double post, Gerolf