Swift 将场景/USDZ文件动态缩放到平面？

目前，我的应用程序正在跟踪图像。一旦找到，它会将三维模型放置在其顶部。我的问题是：是否可以将USDZ/场景文件自动缩放到飞机上

我目前正在跟踪一张明信片（5X7英寸），我希望该模型在被检测到后可以简单地放在明信片上（与我的大多数3d模型相比，它非常小）。我目前不得不手动进入每个文件并进行缩放，但这需要大量的手动时间

我认为有一种更简单的方法可以通过编程来扩展模型，但我不确定

class ViewController: UIViewController, ARSCNViewDelegate {
    
    @IBOutlet var sceneView: ARSCNView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        sceneView.delegate = self
    }
    
    override func viewWillAppear(_ animated: Bool) {
            super.viewWillAppear(animated)
            
            let configuration = ARImageTrackingConfiguration()
            
            guard let trackedImages = ARReferenceImage.referenceImages(inGroupNamed: "Photos", bundle: Bundle.main) else {
                print("No images available")
                return
            }
            
            configuration.trackingImages = trackedImages
            configuration.maximumNumberOfTrackedImages = 7
            
            sceneView.session.run(configuration)
        }
    

//MARK-:CODE WHERE I PLACE MY 3D MODEL

        func renderer(_ renderer: SCNSceneRenderer, nodeFor anchor: ARAnchor) -> SCNNode? {
            
            let node = SCNNode()
            
            if let imageAnchor = anchor as? ARImageAnchor {
                let plane = SCNPlane(width: imageAnchor.referenceImage.physicalSize.width, height: imageAnchor.referenceImage.physicalSize.height)

                plane.firstMaterial?.diffuse.contents = UIColor(white: 1, alpha: 0.8)

                let planeNode = SCNNode(geometry: plane)
                planeNode.eulerAngles.x = -.pi / 2

                guard let url = Bundle.main.url(forResource: "hamburguer", withExtension: "usdz") else { fatalError() }
                let mdlAsset = MDLAsset(url: url)
                let shipScene = SCNScene(mdlAsset: mdlAsset)
//                let shipScene = SCNScene(named: "retro.scn")!
                let shipNode = shipScene.rootNode.childNodes.first!

                shipNode.position = SCNVector3Zero
                shipNode.position.z = 0.15

                planeNode.addChildNode(shipNode)
                
                node.addChildNode(planeNode)
            }
            return node
        }
    
    
}
       

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您可以尝试使用以下内容：

    let width     = 10 //calculate the length of the target image
    let nodeWidth = shipNodeLength //calcualate the length of the original model
    if width > 0 {
        if nodeWidth > width {
            scale = width/nodeWidth
        } else {
            scale = nodeWidth/width
        }
    }
    
    shipNode.scale = SCNVector3(scale, scale, scale)

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嗨@brockhampton！在这里，在StackOverflow上，向上投票一个被接受的答案是一种很好且常见的做法。很抱歉这么说，但我看不到有人对答案投了赞成票（上箭头）。我只是这么做了。非常感谢。