On Sep 4, 2013, at 10:56 , Jonathan Taylor <jonathan.tay...@glasgow.ac.uk> wrote:
> On 3 Sep 2013, at 19:49, Marcel Weiher <marcel.wei...@gmail.com> wrote: >> Unless there is some dire reason not to do this, I would make a copy on the >> main thread every time the UI changes, and stash that copy somewhere the >> worker thread can access it easily. > > That's a really good plan, I realised that last night. I had been stuck > thinking about kind of the opposite approach (make a copy on each invocation > of the processing algorithm), but this makes a lot of sense. How does this > sound: > > When the UI leads to changes in the (mutable) primary object I'll make a copy > stored in an immutable shadow object (from the main thread). > Whenever the algorithm is invoked (from a secondary thread in response to > receipt of a frame) I retain the immutable shadow object and pass this > pointer to the algorithm. Sounds pretty good to me. I’d probably stash it in an instance variable. In a sense, this is a variant of the immutability that Ian and Jens suggested: create a copy that you won’t mutate. > From what Jens and others have said, it's my understanding that if the > property for the (immutable) shadow object is designated atomic/retain then I > wouldn't need a mutex to access it. Yep. Marcel _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
