如何使用ARKit检测触摸并显示新的SCNPlane？

Question

现在我能够SCNPlane在检测到卡片时显示不同的内容.显示后SCNPlanes,用户触摸任何平面以显示新的SCNPlane.但是现在触摸工作正常但新SCNPlane的没有显示.

这是我尝试过的代码:

var cake_1_PlaneNode : SCNNode? = nil

func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {

    guard let imageAnchor = anchor as? ARImageAnchor else { return }

    if let imageName  = imageAnchor.referenceImage.name {            
        print(imageName)

        if imageName == "menu" {

            // Check To See The Detected Size Of Our menu Card (Should By 5cm*3cm)
            let menuCardWidth = imageAnchor.referenceImage.physicalSize.width
            let menuCardHeight =  imageAnchor.referenceImage.physicalSize.height

            print(
                """
                We Have Detected menu Card With Name \(imageName)
                \(imageName)'s Width Is \(menuCardWidth)
                \(imageName)'s Height Is \(menuCardHeight)
                """)

            //raspberry
            //cake 1

            let cake_1_Plane = SCNPlane(width: 0.045, height: 0.045)
            cake_1_Plane.firstMaterial?.diffuse.contents = UIImage(named: "france")
            cake_1_Plane.cornerRadius = 0.01

            let cake_1_PlaneNode = SCNNode(geometry: cake_1_Plane)
            self.cake_1_PlaneNode = cake_1_PlaneNode
            cake_1_PlaneNode.eulerAngles.x = -.pi/2
            cake_1_PlaneNode.runAction(SCNAction.moveBy(x: 0.15, y: 0, z: -0.125, duration: 0.75))

            node.addChildNode(cake_1_PlaneNode)
            self.sceneView.scene.rootNode.addChildNode(node)                
        }  
   }       

   override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {

    let touch = touches.first as! UITouch
    if(touch.view == self.sceneView){
        //print("touch working")
        let viewTouchLocation:CGPoint = touch.location(in: sceneView)
        guard let result = sceneView.hitTest(viewTouchLocation, options: nil).first else {
            return
        }

        if let planeNode = cake_1_PlaneNode, cake_1_PlaneNode == result.node{
            print("match")
            cake_1() 
        }
    }
}

func cake_1() {

    let plane = SCNPlane(width: 0.15  , height: 0.15)
    plane.firstMaterial?.diffuse.contents = UIColor.black.withAlphaComponent(0.75)

    let planeNodee = SCNNode(geometry: plane)
    planeNodee.eulerAngles.x = -.pi / 2
    planeNodee.runAction(SCNAction.moveBy(x: 0.21, y: 0, z: 0, duration: 0))

} //cake_1

点击此链接:在ARKit中检测SCNNode上的触摸.

Answer 1

查看代码,我可以看到几个问题(更不用说变量和方法的命名约定).

首先,您正在创建一个Global Variable您已声明的内容:

var cake_1_PlaneNode : SCNNode? = nil

但是你在你的同时使用a Local和Global Variablefor :cake_1_PlaneNodeDelegate Callback

let cake_1_PlaneNode = SCNNode(geometry: cake_1_Plane)
self.cake_1_PlaneNode = cake_1_PlaneNode

这应该只是这样读:

self.cake_1_PlaneNode = SCNNode(geometry: cake_1_Plane)

其次,你正在添加你cake_1_PlaneNode的rootNode,ARSCNView而不是你检测到的ARImageAnchor,这可能是你不想做的事情,因为当ARAnchor检测到a时:

您可以通过将几何体(或其他SceneKit功能)附加到此节点或添加子节点来为锚点提供可视内容.

因此,这种方法(除非你真的想这样做)是不必要的.

剩下的问题在于你的cake_1功能本身.

首先,你实际上并没有把你planeNodee的sceneHierachy.

由于您尚未指定是否planeNode应将新初始化的内容直接添加到您ARSCNView或childNode您cake_1_planeNode的中,因此function应包括以下内容之一:

self.sceneView.scene.rootNode.addChildNode(planeNodee)    
self.cake_1_planeNode.addChildNode(planeNodee)

此外,可能也没有必要旋转你planeNodee的默认情况下,SCNPlane垂直渲染.

由于您没有规定放置内容的位置,因此可能-.pi / 2不需要使用,因为这可能使肉眼几乎看不见.

另一个问题也可能导致您在实际添加节点时没有看到您的节点是Z位置.

如果您在同一位置设置2个节点,您可能会遇到一个问题Z-fighting(您可以在这里阅读更多信息).因此,您可能应该在添加节点时稍微向前移动添加的节点,例如SCNVector3 (0,0,0.001)为了解决这个问题.

基于所有这些要点,我在下面提供了一个完整的工作和评论示例:

import UIKit
import ARKit

//-------------------------
//MARK: - ARSCNViewDelegate
//-------------------------

extension ViewController: ARSCNViewDelegate {

    func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {

        //1. Check We Have An ARImageAnchor, Then Get It's Reference Image & Name
        guard let imageAnchor = anchor as? ARImageAnchor else { return }

        let detectedTarget = imageAnchor.referenceImage

        guard let detectedTargetName = detectedTarget.name  else { return }

        //2. If We Have Detected Our Virtual Menu Then Add The CakeOnePlane
        if detectedTargetName == "cakeMenu" {

            let cakeOnePlaneGeometry = SCNPlane(width: 0.045, height: 0.045)
            cakeOnePlaneGeometry.firstMaterial?.diffuse.contents = UIColor.cyan
            cakeOnePlaneGeometry.cornerRadius = 0.01

            let cakeOnPlaneNode = SCNNode(geometry: cakeOnePlaneGeometry)
            cakeOnPlaneNode.eulerAngles.x = -.pi/2

            //3. To Allow Us To Easily Keep Track Our Our Currently Added Node We Will Assign It A Unique Name
            cakeOnPlaneNode.name = "Strawberry Cake"

            node.addChildNode(cakeOnPlaneNode)
            cakeOnPlaneNode.runAction(SCNAction.moveBy(x: 0.15, y: 0, z: 0, duration: 0.75))


        }
    }
}

class ViewController: UIViewController {

    @IBOutlet var augmentedRealityView: ARSCNView!
    let augmentedRealitySession = ARSession()
    let configuration = ARWorldTrackingConfiguration()

    //------------------
    //MARK: - Life Cycle
    //------------------

    override func viewDidLoad() {
        super.viewDidLoad()

        setupARSession()
    }


    //-----------------
    //MARK: - ARSession
    //-----------------

    /// Runs The ARSession
    func setupARSession(){

        //1. Load Our Detection Images
        guard let detectionImages = ARReferenceImage.referenceImages(inGroupNamed: "AR Resources", bundle: nil) else { return }

        //2. Configure & Run Our ARSession
        augmentedRealityView.session = augmentedRealitySession
        augmentedRealityView.delegate = self
        configuration.detectionImages = detectionImages
        augmentedRealitySession.run(configuration, options: [.resetTracking, .removeExistingAnchors])

    }

    //--------------------
    //MARK: - Interaction
    //--------------------

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {

        //1. Get The Current Touch Location & Perform An ARSCNHitTest To Check For Any Hit SCNNode's
        guard let currentTouchLocation = touches.first?.location(in: self.augmentedRealityView),
             let hitTestNode = self.augmentedRealityView.hitTest(currentTouchLocation, options: nil).first?.node else { return }

        //2. If We Have Hit Our Strawberry Cake Then We Call Our makeCakeOnNode Function
        if let cakeID = hitTestNode.name, cakeID == "Strawberry Cake"{

            makeCakeOnNode(hitTestNode)

        }
    }


    /// Adds An SCNPlane To A Detected Cake Target
    ///
    /// - Parameter node: SCNNode
    func makeCakeOnNode(_ node: SCNNode){

        let planeGeometry = SCNPlane(width: 0.15  , height: 0.15)
        planeGeometry.firstMaterial?.diffuse.contents = UIColor.black.withAlphaComponent(0.75)

        let planeNode = SCNNode(geometry: planeGeometry)
        planeNode.position = SCNVector3(0, 0, 0.001)
        planeNode.runAction(SCNAction.moveBy(x: 0.21, y: 0, z: 0, duration: 0))
        node.addChildNode(planeNode)

    }
}

这在我的设备上产生以下内容:

对于您的信息,这似乎表明您放置内容的计算是关闭的(除非当然这是期望的结果).

正如您所看到的,所有内容都正确呈现,但是这些内容的间距非常大,因此您可能需要稍微平移设备,以便在进一步测试和开发时看到它们.

希望能帮助到你...