NSClipView
NSClipView is a subclass of NSView in the AppKit framework that provides clipping of its content to a specified rectangle. In macOS applications that use scrolling, an NSScrollView uses an NSClipView as its content view to display a portion of a larger document. The clip view draws only within its bounds, so drawing outside the visible area is not rendered.
The clip view maintains a reference to its documentView—the view that contains the full content to be
Typical usage involves setting the document view with setDocumentView: and obtaining it with documentView. The clip
Customization and notes: NSClipView is usually not subclassed, but it can be overridden to customize clipping