再次触摸时如何删除scnplane？

Question

当用户点击飞机时，我可以添加新的 scnplane。但是现在，点击同一个 scnplane，它会再次添加新的 scnplane，而不是删除。

最初检测到参考图像时，它会在菜单卡的一侧列出蛋糕的图像、名称和评分。用户点击评分，它将列出用户评分。

这是我尝试过的代码：

  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.sceneView),
        let hitTestNode = self.sceneView.hitTest(currentTouchLocation, options: nil).first?.node else { return }


    if let lableName = hitTestNode.name {
        print("touch working")
        if lableName == "lableNode"{


            makeCakeOnNode(hitTestNode)



        } else if lableName == "AllLabelNode" {

            makeCakeOnNode1(hitTestNode)

        } else if lableName == "fruitNode" {

            makeCakeOnNode2(hitTestNode)

        }

    }
}


func makeCakeOnNode(_ node: SCNNode){

    let planeGeometry = SCNPlane(width: 0.18  , height: 0.15)

    planeGeometry.firstMaterial?.diffuse.contents = UIColor.black.withAlphaComponent(0)




    planeNode0 = SCNNode(geometry: planeGeometry)
    planeNode0?.runAction(SCNAction.moveBy(x: -0.2, y: -0.15, z: 0, duration: 0))

                    let overlayNode = self.getNode(withImageName: "menu")
                    print("overlay::\(overlayNode)")

    let newPlane = SCNPlane(width: 0.15, height: 0.10)
    newPlane.firstMaterial?.diffuse.contents = UIImage(named: "cake_detail")

    let newPlaneNode = SCNNode(geometry: newPlane)
    newPlaneNode.eulerAngles.x = -.pi / 2
    newPlaneNode.runAction(SCNAction.moveBy(x: -0.2, y: -0.15, z: 0, duration: 0))

    node.addChildNode(planeNode0!)
    planeNode0?.addChildNode(overlayNode)
    planeNode0?.addChildNode(newPlaneNode)
    if planeBool == true {

        planeNode1?.isHidden = true
        planeNode2?.isHidden = true
        planeNode0?.isHidden = false
        planeBool = false

    } else {

        print("plane removed")
        planeNode0?.isHidden = true
        planeNode1?.isHidden = true
        planeNode2?.isHidden = true

        planeBool = true
    }


}

Answer 1

您可以使用的一种方法是为您添加的每个节点创建一个全局变量，例如：

 var labelNode: SCNNode?
 var allLabelNode: SCNNode?
 var fruitNode: SCNNode?

然后你可以进行测试看看他们是否是nil。如果节点是nil，则创建它，否则删除它，例如：

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. self.sceneView),
        let hitTestNode = self.sceneView.hitTest(currentTouchLocation, options: nil).first?.node
        else { return }

    //2. Enumerate The Nodes We Have By Name
    switch hitTestNode.name {
    case "lableNode":

        //1. If The LabelNode Doesnt Exist Create It
        if labelNode == nil{
            //Create The Node Here
        }else{
           labelNode?.removeFromParentNode()
           labelNode = nil
        }

    case "AllLabelNode":

        //2. If The LabelNode Doesnt Exist Create It
        if allLabelNode == nil{
            //Create The Node Here
        }else{
            allLabelNode?.removeFromParentNode()
            allLabelNode = nil
        }

    case "fruitNode":

        //3. If The LabelNode Doesnt Exist Create It
        if fruitNode == nil{
            //Create The Node Here
        }else{
            fruitNode?.removeFromParentNode()
            fruitNode = nil
        }

    default:
        return
    }

}

请注意，Touches 方法可能应该被重构，但它应该足以为您指明正确的方向......