Hi guys, I tweaked, or at least I think I did, the app_server's update code to update only what's needed, so correct results should appear on-screen. Now, this appears to function well, but I need something from DisplayDriver to work perfectly. I need DisplayDriver subclasses to implement ConstainClippingRegion() and _completely_ ignore LayerData::clipReg. ConstainClippingRegion() should function like BView's version, with a minor difference - passing an empty region should be handled exactly like when passing NULL. Now, about CopyRegionList() I will explain this tomorrow as I'm pretty tired. I can give you a hint, it's _really_useful when resizing a window with lots of views(aligned to center or right) inside it. BTW, this is one area where our app_server does better that R5's one, as that completely redraws center or right aligned views (tested that). It can do better if that method would be optimized, as there is _plenty_ of room to do that. :-) b-bye for now, Adi.