节点名称被USDZ模型覆盖

Question

我目前正在开发一个iOS应用程序，使用ARKit和SceneKit进行增强现实。我有一个问题，而加载一个。usdz模型到场景。我可以正确地将其加载到场景中，但是，当我尝试在点击它后获得节点名称(我在其中加载了。usdz模型)时，它返回。usdz名称而不是我给它的名称。

我用来加载。usdz模型的代码是:

let mdlAsset = MDLAsset(url: urlPath)
mdlAsset.loadTextures()
let asset = mdlAsset.object(at: 0) // extract first object
var assetNode = SCNNode(mdlObject: asset)
assetNode = SCNNode(mdlObject: asset)
assetNode.name = "Node-2"
sceneView.scene.rootNode.addChildNode(assetNode)

要捕获节点上的点击，代码如下:

@objc func handleTap(recognizer: UITapGestureRecognizer){

let location = recognizer.location(in: sceneView)
let results = sceneView.hitTest(location, options: nil)
guard recognizer.state == .ended else { return }
if results.count > 0 {
let result = results[0] as SCNHitTestResult
let node = result.node  
print(node.name)    
}     
}

正如我之前提到的，当我点击对象时，它会打印可选("Sphere_0"值，可以在模型详细信息页面的右上角找到。我期望的正确值是"Node-2"

Answer 1

您的USDZ模型的名称没有被覆盖。这是SceneKit命中测试和场景层次结构的特性。当您执行命中测试搜索时，SceneKit沿着您指定的射线查找SCNGeometry对象(不是主节点)。因此，一旦完成命中测试，您所需要做的就是找到相应的父节点。

试试这个代码:

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)
}
}

你的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
}
}
}