51efeb6834
Scroll-bars are now hidden unless the cursor approaches them, in which case they smoothly grow and become more & more visible. Note that since 0d309144020168e55, scroll-bars are drawn on top of editor contents. There's no more jumping of buttons when scroll-bars appear. Technical notes: * AZones are used to adjust scrollbars based on mouse movements We may want to support screen level AZones if we want scrollbars to also smoothly appear when approaching them from a different area. I also plan to make further changes to AZones to clean up stuff a bit. * Had to move AZone handling to a post ARegion init stage, since we need the updated View2D data from there. * View2D masks and scroller rectangles are now updated on every redraw. It's cheap to do that though.