The intelligence boosting power of posting a question strikes again.
The problem was that in the Mac OS X Storyboard, the "Rendering API" of the
SCNView was initialized to "unknown" when it needed to be "Metal"
(curiously, "OpenGL" and "Default" don't render the overlay either). This
is the "rend
I have struggled long and hard with this .. I think I’ve looked at 'everything'
related on Google, but I’m still flummoxed.
This is on Mac OS 10.11.3, build with Xcode 7.2, and this is what I think is
the salient code.
override func viewDidLoad() {
super.viewDidLoad()
let s
