Hi Author,
Yes, this must be possible. I recall there was a Collision Detection demo application that was multi-threaded where computations were performed in a work thread while GUI still remained responsive and the user could rotate, zoom, pan the model.
You should set MMGT_REENTRANT variable to 1 or use Standard::SetReentrant(Standard_True) before your fork the threads.
By the way, note that Qt requires that the event loop (and hence all GUI) runs in a main thread.
Hope this helps.
Commenter-1
---
opencascade.blogspot.com - the Open CASCADE blog