Apply multiple rotations to ARKit SCNNode - swift

Question

I'm working with an AR app that uses Apple's Focus Square to guide user interaction on both vertical and horizontal surfaces. However, it's only designed to work on horizontal surfaces. I have modified the method that updates the square's rotation to account for vertical surfaces as well. However, using the method that they used only one rotation can be performed at a time, whereas in order to have the square positioned properly on a horizontal surface I need to have two rotations performed (one to apply the original yaw correction, and one to pitch the square vertically).
The relevant code is below, but the specific changes I made are only at the beginning and end.
// MARK: - Appearence
func update(for position: float3, planeAnchor: ARPlaneAnchor?, camera: ARCamera?) {
lastPosition = position
let thisAlignment = planeAnchor?.alignment ?? .horizontal
if thisAlignment != lastAlignment {
lastAlignment = thisAlignment
print("alignmentChanged")
recentFocusSquarePositions = []
}
if let anchor = planeAnchor {
close(flash: !anchorsOfVisitedPlanes.contains(anchor))
lastPositionOnPlane = position
anchorsOfVisitedPlanes.insert(anchor)
} else {
open()
}
updateTransform(for: position, alignment: thisAlignment, camera: camera)
}
private func updateTransform(for position: float3, alignment: ARPlaneAnchor.Alignment, camera: ARCamera?) {
// add to list of recent positions
recentFocusSquarePositions.append(position)
// remove anything older than the last 8
recentFocusSquarePositions.keepLast(8)
// move to average of recent positions to avoid jitter
if let average = recentFocusSquarePositions.average {
self.simdPosition = average
self.setUniformScale(scaleBasedOnDistance(camera: camera))
}
// Correct y rotation of camera square
if let camera = camera {
let tilt = abs(camera.eulerAngles.x)
let threshold1: Float = .pi / 2 * 0.65
let threshold2: Float = .pi / 2 * 0.75
let yaw = atan2f(camera.transform.columns.0.x, camera.transform.columns.1.x)
var angle: Float = 0
switch tilt {
case 0..<threshold1:
angle = camera.eulerAngles.y
case threshold1..<threshold2:
let relativeInRange = abs((tilt - threshold1) / (threshold2 - threshold1))
let normalizedY = normalize(camera.eulerAngles.y, forMinimalRotationTo: yaw)
angle = normalizedY * (1 - relativeInRange) + yaw * relativeInRange
default:
angle = yaw
}
if alignment == .vertical{
self.rotation = SCNVector4(0, 1, 1, Float.pi)
} else {
self.rotation = SCNVector4(0, 1, 0, angle)
}
}
}
My goal is to have both the rotations in the control statement at the end performed on the object. If the else statement is removed, only that rotation is applied and the square remains horizontal. I have tried making both modifications to the transform directly using SCNMatrix4MakeRotation(_:_:_:_:) but this caused the square to spin endlessly and position itself incorrectly. I also tried adjusting the node's Pivot but this resulted in no visible changes to the object.