Hi again: 'Axel wrote: > IIRC the accelerant engine even has an interface for that: every > change > gets a token, and you can sync to them. Only then the rendering > pipeline will be guaranteed to be empty. IOW that looks like a good > time to do the back-to-front buffer copy. This is right I think. But I just can't resist saying this: ->no specs, so most of the time not implemented. accelerant waits until engine _completely) idle.... Which means: you can use it, but keep in the back of your head that if it isn't implemented, the system should remain nicely useable. Rudolf.