OSX: Updating pixel data for image

Question

Heya
I have a buffer of pixel data that I need to update/change once every 25ms or so.  What's the best way of creating a UI element that I can update on the fly?  It looks like my old way of creating an NSBitmapImageRef and getting a pointer to the data via getBitmapDataPlanes was broken in the transition from 10.5-10.6 [1].  A workaround is to create a new NSBitmapImageRef every time I want to update and render a frame, but that creates a ton of object churn.  I figure there's got to be a better way to have byte-level access to a UI image of some kind.  Thoughts?
Thanks
[1] https://groups.google.com/forum/?fromgroups#!topic/cocoa-dev/f05K9ZaafMw

Answer 1

Theoretically it may be doable assuming the tool used to modify B triggers proper events (not every tool does, unfortunately) AND your updates to layer A can be performed without disrupting user's work on B. What you'd need to do in this case is to implement an automation plugin based on Listener from the SDK samples that would monitor the events. Upon the event you'd need to determine the activate layer in your C++ code and if it's B then update A. The problematic part here would be whether you'd able to modify the non-current layer in a fashion that doesn't interrupt user's work on B (for example, you probably wouldn't want upon any change on B to change the current layer to A which would cause the focus to jump to A and then go back) and this would depend on the the type of changes you'd like to make there.
Anyway, this would be the general direction I'd take here.
HTH
ivar