Smooth object rotation in ARSCNView - swift

Question

I'm trying to make my pan gesture to be as smooth as the jigspace app when rotating 3d objects in AR. Here's what I have right now:
#objc func rotateObject(sender: UIPanGestureRecognizer) {
let sceneView = sender.view as! ARSCNView
var currentAngleY: Float = 0.0
let translation = sender.translation(in: sceneView)
var newAngleY = Float(translation.x)*Float(Double.pi)/180
sceneView.scene.rootNode.enumerateChildNodes { (node, stop) in
if sender.state == .changed {
newAngleY -= currentAngleY
node.eulerAngles.y = newAngleY
} else if sender.state == .ended {
currentAngleY = newAngleY
node.removeAllActions()
}
}
}
There seems to be a delay when I'm using it and I'm trying to figure out how to make the rotation as smooth as possible, again, kinda like jigspace or the Ikea app.
I've also noticed that when I try to rotate the object when it's in a certain angle, it could get quite awkward.

Answer 1

Looking at your rotate object function it seems like some of the logic is not quite right.
Firstly, I believe that the var currentAngleY: Float = 0 should be outside of your function body.
Secondly you should be adding the currentAngleY to the newAngleY variable e.g:
/// Rotates The Models On Their YAxis
///
/// - Parameter gesture: UIPanGestureRecognizer
#objc func rotateModels(_ gesture: UIPanGestureRecognizer) {
let translation = gesture.translation(in: gesture.view!)
var newAngleY = (Float)(translation.x)*(Float)(Double.pi)/180.0
newAngleY += currentAngleY
DispatchQueue.main.async {
self.sceneView.scene.rootNode.enumerateChildNodes { (node, _) in
node.eulerAngles.y = newAngleY
}
}
if(gesture.state == .ended) { currentAngleY = newAngleY }
}
An example therefore of this in a working context would be like so:
class ViewController: UIViewController {
#IBOutlet var augmentedRealityView: ARSCNView!
var currentAngleY: Float = 0
//-----------------------
// MARK: - View LifeCycle
//-----------------------
override func viewDidLoad() {
super.viewDidLoad()
//1. Generate Our Three Box Nodes
generateBoxNodes()
//2. Create Our Rotation Gesture
let rotateGesture = UIPanGestureRecognizer(target: self, action: #selector(rotateModels(_:)))
self.view.addGestureRecognizer(rotateGesture)
//3. Run The Session
let configuration = ARWorldTrackingConfiguration()
augmentedRealityView.session.run(configuration)
}
//------------------------
// MARK: - Node Generation
//------------------------
/// Generates Three SCNNodes With An SCNBox Geometry
func generateBoxNodes(){
//1. Create An Array Of Colours For Each Face
let colours: [UIColor] = [.red, .green, .blue, .purple, .cyan, .black]
//2. Create An SCNNode Wih An SCNBox Geometry
let boxNode = SCNNode()
let boxGeometry = SCNBox(width: 0.1, height: 0.1, length: 0.1, chamferRadius: 0.01)
boxNode.geometry = boxGeometry
//3. Create A Different Material For Each Face
var materials = [SCNMaterial]()
for i in 0..<5{
let faceMaterial = SCNMaterial()
faceMaterial.diffuse.contents = colours[i]
materials.append(faceMaterial)
}
//4. Set The Geometries Materials
boxNode.geometry?.materials = materials
//5. Create Two More Nodes By Cloning The First One
let secondBox = boxNode.flattenedClone()
let thirdBox = boxNode.flattenedClone()
//6. Position Them In A Line & Add To The Scene
boxNode.position = SCNVector3(-0.2, 0, -1.5)
secondBox.position = SCNVector3(0, 0, -1.5)
thirdBox.position = SCNVector3(0.2, 0, -1.5)
self.augmentedRealityView.scene.rootNode.addChildNode(boxNode)
self.augmentedRealityView.scene.rootNode.addChildNode(secondBox)
self.augmentedRealityView.scene.rootNode.addChildNode(thirdBox)
}
//----------------------
// MARK: - Node Rotation
//----------------------
/// Rotates The Models On Their YAxis
///
/// - Parameter gesture: UIPanGestureRecognizer
#objc func rotateModels(_ gesture: UIPanGestureRecognizer) {
let translation = gesture.translation(in: gesture.view!)
var newAngleY = (Float)(translation.x)*(Float)(Double.pi)/180.0
newAngleY += currentAngleY
DispatchQueue.main.async {
self.augmentedRealityView.scene.rootNode.enumerateChildNodes { (node, _) in
node.eulerAngles.y = newAngleY
}
}
if(gesture.state == .ended) { currentAngleY = newAngleY }
}
}
Hope it helps...