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如何使用ARKit检测触摸并显示新屏幕?

scnnode arkit scenekit swift

PvDev · 技术社区 · 6 年前

SCNPlane ,当检测到卡时。显示后 SCNPlanes ,用户触摸任何平面以显示新的 . 但现在触摸正常工作,但新的 SCN平面 没有显示。

以下是我尝试过的代码:

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

Detect touch on SCNNode in ARKit .

2 回复 | 直到 6 年前

BlackMirrorz 6 年前

查看您的代码,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,你在创造一个 Global Variable

var cake_1_PlaneNode : SCNNode? = nil

Local 全局变量 cake_1_PlaneNode 在你的 Delegate Callback :

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

self.cake_1_PlaneNode = SCNNode(geometry: cake_1_Plane)

第二,你正在添加你的 蛋糕\u 1 \u平面节点 rootNode 你的 ARSCNView 而不是你的 ARImageAnchor 这可能是你不想做的,因为 ARAnchor

可以通过附着几何图形为锚定提供视觉内容

因此,这种方法(除非你真的想这样做)是不必要的。

cake_1 功能本身。

首先,你并不是真的在添加你的 planeNodee 给你的 sceneHierachy

因为你还没有指定 planeNode ARSCNView公司 childNode 你的 cake_1_planeNode 你的 function 应包括以下内容之一:

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

平面节点 因为默认情况下 SCNPlane 垂直渲染。

因为你还没有规定你将在哪里放置你的内容,它可能是使用 -.pi / 2

另一个问题,也可以解释你没有看到你的节点,当你实际添加它,是Z位置。

Z-fighting (您可以阅读更多 here ). 因此,在添加节点时,您可能应该稍微向前移动添加的节点。 SCNVector3 (0,0,0.001) 来解释这个。

基于所有这些观点,我提供了一个完整的工作和评论的例子如下:

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)

    }
}

在我的设备上产生以下结果:

为您提供信息,这似乎表明您放置内容的计算是关闭的(当然,除非这是期望的结果)。

如您所见,所有内容都正确呈现,但是这些内容的间距相当大,因此,在进一步测试和开发时,您可能需要稍微平移设备才能看到所有内容。

希望对你有帮助。。。

SilentK Krunal 6 年前

***请使用描述性和明确的名称为您的变量和函数,这是很难阅读和理解您的代码。您可以在此处阅读更多有关swift样式指南的信息: https://github.com/raywenderlich/swift-style-guide#naming

当用户触摸屏幕时,您正在创建一个新平面,但您没有将该平面添加到场景中,因此“cake_1()”函数只创建一个新平面。当ARKit检测到图像时,它会自动创建一个空节点,并将其添加到我们的场景中,位于检测到的图像的中心。当检测到图像时,我们必须首先保留对ARKit为我们添加的节点的引用。将此变量添加到类的顶部:

var detectedImageNode: SCNNode?

然后在func renderer(renderer:didAdd node:,for anchor:)中添加以下行:

detectedImageNode = node

现在我们有了对节点的引用,我们可以轻松地添加和删除其他节点。

if let detectedImageNode = detectedImageNode {
    cake_1_PlaneNode?.removeFromParentNode()
    detectedImageNode.addChildNode(planeNodee)
}

最终代码应如下所示:

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" {

            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)
            // No need to add the following line. The node is already added to the scene
            //self.sceneView.scene.rootNode.addChildNode(node)                
            detectedImageNode = node
        }
    }
}

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

        if let detectedImageNode = detectedImageNode {
            cake_1_PlaneNode?.removeFromParentNode()
            detectedImageNode.addChildNode(planeNodee)
        }    
    }

替代解决方案

如果你只是想改变平面的图像,那么更简单的方法就是改变平面的纹理。将蛋糕\u 1()的内容替换为:

if let planeGeometry = cake_1_PlaneNode?.geometry {
    planeGeometry.firstMaterial?.diffuse.contents = UIImage(named: "newImage")
}