canDrawConcurrently
A Boolean value indicating whether the view can draw its contents on a background thread.
Declaration
var canDrawConcurrently: Bool { get set }Discussion
If your view’s draw(_:) implementation can draw safely on a background thread, set this property to true. Doing so gives AppKit the ability to run your view’s drawing code off the app’s main thread, which can improve performance. The view’s window must also have its allowsConcurrentViewDrawing property set to true (the default) for threaded view drawing to occur.