[I've already submitted this via Feedback Assistant, issue FB8904434. Providing a brief summary here for other affected developers to discover.] The behavior of unprojectPoint(_:) has changed in iOS 14, for both ARSCNView and SCNView. The unprojected point should be most distant for a z-value of 1.0. But in iOS 14, it is actually most distant for a z-value of 0.5. Background When you unproject a screen coordinate, you provide a z value between 0.0 and 1.0 to specify the depth. 0.0 corresponds to the near clipping plane, 1.0 to the far clipping plane, and intermediate values map in between. Expected/documented behavior: Distance from the unprojected point to the camera should increase monotonically (though not necessarily linearly) with z. Observed behavior: iOS 13: distance increases monotonically with z. Takes a huge jump between z = 0.9 and z = 1.0. iOS 14: distance increases for z 0.0 to 0.5, then decreases. Takes a huge jump on either side of z = 0.5. Note I am surprised by just how non-linear the mapping is, under either version of iOS. For example, under iOS 13 as z varies from 0.0 to 0.9, the distance changes from 0.5 mm to 5 mm. Then at 1.0 the distance jumps to over 1000 meters.

Anybody else seeing something similar to this? (I've just reported it via Feedback Assistant)iOS 13.1.2 is misbehaving when supportedInterfaceOrientations == .portrait:1. In Xcode, create new “Augmented Reality App” project.2. In ViewController.swift/viewDidLoad(), add debug UI: sceneView.debugOptions = [ARSCNDebugOptions.showFeaturePoints, ARSCNDebugOptions.showWorldOrigin]3. In ViewContoller.swift, add: override var supportedInterfaceOrientations: UIInterfaceOrientationMask { return .portrait }4. Using an iOS 12 device, hold device in landscape-right orientation and launch the app.=> As expected, camera image is rotated counterclockwise.=> As expected, the AR model and AR axes are also rotated counterclockwise.=> As expected, feature points appear reasonable.5. Using an iOS 13.1.2 device, hold device in landscape-right orientation and launch the app.=> As expected, camera image is rotated counterclockwise.=> Unexpectedly, the AR model and AR axes are NOT rotated counterclockwise.=> Unexpectedly, feature points appear quite wrong.