Question

我已经编写了跟踪车轮的代码并在检测到车轮的SCNScene对象“ .scn”被自动放置

现在我尝试添加更多选项来替换自动放置的车轮带有新的“ .scn”对象

但是我总是收到错误消息，旧放置的“ .scn”对象不变

 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 = 1

        sceneView.session.run(configuration)
    }

 func renderer( _ renderer: SCNSceneRenderer, nodeFor anchor: ARAnchor) -> 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)
            plane.cornerRadius = 0.7
            let planeNode = SCNNode(geometry: plane)
            planeNode.eulerAngles.x = -.pi / 2
            let  jantScene = SCNScene(named: "art.scnassets/wheel.scn")
            self.jantNode = jantScene?.rootNode.childNode(withName: "wheel", recursively: true)
            jantNode.position = SCNVector3Zero
            jantNode.position.z = 0.01
            jantNode.scale = SCNVector3(x: 0.01225, y: 0.01225, z: 0.01225)
            planeNode.addChildNode(jantNode)
            node.addChildNode(planeNode)
        }
        return node
    }

当我单击按钮时，添加了对象但未删除旧对象


  @objc func buttonClicked(sender : UIButton){
         let plane = SCNPlane(width: 0.7, height:  0.7)
         plane.firstMaterial?.diffuse.contents = UIColor(white: -1, alpha: 0.8)
        plane.cornerRadius = 0.7
         let planeNode = SCNNode(geometry: plane)
        planeNode.eulerAngles.x = -.pi / 2
         jantScene = SCNScene(named: availableWheels[1])!
          newjantNode = self.jantScene?.rootNode.childNode(withName: "wheel", recursively: true)!
         newjantNode.position = SCNVector3Zero
            newjantNode.position.z = 0.01
          newjantNode.scale = SCNVector3(x: 0.01225, y: 0.01225, z: 0.01225)
          planeNode.addChildNode(newjantNode)
            node.addChildNode(newjantNode)
         }

Answer 1

您需要

呼叫removeFromParentNode()，或者
使用以下命令删除包含节点的所有子节点：

node.childNodes.forEach {
     $0.removeFromParentNode()
}

顺便说一句，加载.scn文件时总是使用SCNReferenceNode。

如何在图像跟踪和检测中的SCNScene之间交换？

1 个答案: