如何识别很多对象并同时添加很多节点？

Question

这是我用于ARImageTrackingConfiguration()的简单对象。

在代码内，我将一个平面和paperPlane添加到已识别的对象上：

    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.green.withAlphaComponent(0.8)
            let planeNode = SCNNode(geometry: plane)
            planeNode.eulerAngles.x = -.pi / 2
            planeNode.position.y = 0
            let paperPlaneScene = SCNScene(named: "Scenes.scnassets/paperPlane.scn")!
            let paperPlaneNode = paperPlaneScene.rootNode.childNodes.first!
            paperPlaneNode.position = SCNVector3Zero
            paperPlaneNode.position.z = 0.1
            paperPlaneNode.eulerAngles.y = -.pi / 2
            paperPlaneNode.eulerAngles.z = .pi
            planeNode.addChildNode(paperPlaneNode)
            node.addChildNode(planeNode)
        }
        return node
    }

但是结果如下：

为什么一次只能识别一个物体？不是每个人？它们被一一识别，但一次也不会被所有人识别。为什么？

Answer 1

要检测4张图像，请使用以下实例属性：

var maximumNumberOfTrackedImages: Int { get set }

或：

guard let reference = ARReferenceImage.referenceImages(inGroupNamed: "ARRes", 
                                                             bundle: nil) 
else {
    fatalError("Missing resources.")
}

let config = ARWorldTrackingConfiguration()
config.maximumNumberOfTrackedImages = 4
config.detectionImages = reference

arView.session.run(config, options: [.resetTracking, .removeExistingAnchors])