How to Create a Scnnode from a .Usdz

How to create a SCNNode from a .usdz?

The correct way to add the .USDZ object is actually creating the scene with the file's URL:

 let scene = try! SCNScene(url: usdzURL, options: [.checkConsistency: true])

Or even creating via Reference Node:

 let referenceNode = SCNReferenceNode(url: usdzURL)
 referenceNode.load()

Load 3d usdz model from network in Scenekit view does not work?

I loaded the model this way and it worked for me:

import SceneKit.ModelIO

func loadModel(){
    
    //1. Get The Path Of The Downloaded File
    let downloadedScenePath = getDocumentsDirectory().appendingPathComponent("nike.usdz")
    
    self.scnView.autoenablesDefaultLighting=true
    self.scnView.showsStatistics=true
    self.scnView.backgroundColor = UIColor.blue
    let asset = MDLAsset(url: downloadedScenePath)
    asset.loadTextures()
    let scene = SCNScene(mdlAsset: asset)
    self.scnView.scene=scene
    self.scnView.allowsCameraControl=true
}

.usdz model has no texture when loaded into scene

Your scene has no light, that's why the object is showing dark. Just add a directional light to your scene:

let spotLight = SCNNode()
spotLight.light = SCNLight()
spotLight.light?.type = .directional

sceneView.scene.rootNode.addChildNode(spotLight)

Node name was overwritten by USDZ model

The name of your USDZ model isn't overridden. It's the peculiarities of SceneKit hit-testing and scene hierarchy. When you perform a hit-test search, SceneKit looks for SCNGeometry objects (not a main node) along the ray you specify. So, all you need to do, once the hit-test is completed, is to find the corresponding parent nodes.

Try this code:

import SceneKit.ModelIO

class GameViewController: UIViewController {
    
    var sceneView: SCNView!
        
    override func viewDidLoad() {
        super.viewDidLoad()
        
        sceneView = (self.view as! SCNView)
        let scene = SCNScene(named: "art.scnassets/ship.scn")!
        sceneView.scene = SCNScene()
        sceneView.backgroundColor = .black
        
        let recog = UITapGestureRecognizer(target: self, action: #selector(tap))
        sceneView.addGestureRecognizer(recog)
        
        // ASSET
        let mdlAsset = MDLAsset(scnScene: scene)
        let asset = mdlAsset.object(at: 0)
        let node = SCNNode(mdlObject: asset.children[0])
        node.name = "Main-Node-Name"                       // former "ship"
        node.childNodes[0].name = "SubNode-Name"           // former "shipMesh"
        node.childNodes[0].childNodes[0].name = "Geo-Name" // former "Scrap_MeshShape"
        sceneView.scene?.rootNode.addChildNode(node)
    }
}

And your hit-testing method:

extension GameViewController {
    
    @objc func tap(recognizer: UITapGestureRecognizer) {
           
        let location = recognizer.location(in: sceneView)
        let results = sceneView.hitTest(location)

        guard recognizer.state == .ended else { return }

        if results.count > 0 {
            let result = results[0] as SCNHitTestResult
            let node = result.node
            
            print(node.name!)                            // Geo-Name
            print(node.parent!.name!)                    // SubNode-Name
            print(node.parent!.parent!.name!)            // Main-Node-Name
        }
    }
}

usdz object is not moving while loaded with SCNReferenceNode

After so many tries , finally i found out that dynamic scaling of the model causing problem , Reference to this

iOS ARKit: Large size object always appears to move with the change in the position of the device camera

I scaled the object to 0.01 for all the axis (x,y and z)

        virtualObject.scale = SCNVector3Make(0.01, 0.01, 0.01)

USDZ export from SceneKit results in dull models

The default lighting model is SCNLightingModelBlinn which means the material used for the plane geometry is not physically based. USDZ only supports physically based materials and upon export SceneKit will try to build a PBR material from the Blinn material, and will infer a roughness on your behalf.

The fix consists in setting lightingModelName to SCNLightingModelPhysicallyBased.

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