ios - 如何对场景 View 中节点的子节点进行hitTest？

Question

我有一个 ARSceneView，我使用 detectionImages 找到一个平面，这样我就可以根据我检测到的图像添加节点。

我的问题是， View 一直在我在“我的图像的节点”中作为子节点添加的节点上方添加一个不可见的平面节点，当我将 TapGestureRecognizer 添加到 sceneView 时，我无法检测到节点，因为它检测到平面。有时它可以工作，但当它添加平面时它不起作用。

当飞机在现场时，我的节点是这些

我希望我的节点是这样的..

▿ 3个元素 - 0:|没有 child > - 1:SCNNode:0x1c41f4100 |光= - 2: SCNNode: 0x1c43e1000 'DetectableChildrenParent' pos(-0.009494 -0.081575 -0.360098) rot(0.997592 -0.060896 0.033189 1.335512) | 2个 child >

和我的 2 个 child 只是可检测节点..

但总是这样

▿ 4个元素 - 0: SCNNode: 0x1c01fcc00 pos(-0.093724 0.119850 -0.060124) rot(-0.981372 0.172364 -0.084866 0.457864) scale(1.000000 1.000000 1.000000) |相机= |没有 child > - 1:SCNNode:0x1c01fc200 |灯= |没有 child > - 2: SCNNode: 0x1c01fd100 'DetectableChildrenParent' pos(-0.149971 0.050361 -0.365586) rot(0.996908 0.061535 -0.048872 1.379775) scale(1.000000 1.000000 01.00) 2个 child > - 3:SCNNode:0x1c01f9f00 |几何= |没有 child >

它总是检测到最后一个节点。

我要检测的代码是这个

@objc func addNodeToScene(withGestureRecognizer recognizer: UIGestureRecognizer) {
            let tapLocation = recognizer.location(in: self.sceneView)
            let hitTestResults = sceneView.hitTest(tapLocation)
            if let node = hitTestResults.first?.node {
                    print(node.name ?? "")
            }
    }

如何运行 HitTest 以仅检查 DetectableChildrenParent 的子级？

Answer 1

假设我已经正确解释了你的问题，你正在寻找的是 SCNHitTestResult Node 的 childNodes 属性，它指的是:

An array of the node’s children in the scene graph hierarchy.

因此我相信你可以尝试这样的事情:

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

    //1. Get The Current Touch Location
    guard let currentTouchLocation = touches.first?.location(in: self.augmentedRealityView),

        //2. Get The Tapped Node From An SCNHitTest
        let hitTestResultNode = self.augmentedRealityView.hitTest(currentTouchLocation, options: nil).first?.node else { return }

    //3. Loop Through The ChildNodes
    for node in hitTestResultNode.childNodes{

        //4. If The Node Has A Name Then Print It Out
        if let validName = node.name{
             print("Node\(validName) Is A Child Node Of \(hitTestResultNode)")
        }

    }

}

或者，您可以尝试寻找最后一个结果，而不是寻找 SCNHitTest 的第一个结果，例如:

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

    //1. Get The Current Touch Location
    guard let currentTouchLocation = touches.first?.location(in: self.augmentedRealityView),

        //2. Get The Tapped Node From An SCNHitTest
        let hitTestResultNode = self.augmentedRealityView.hitTest(currentTouchLocation, options: nil).last?.node else { return }

    //3. Loop Through The ChildNodes
    for node in hitTestResultNode.childNodes{

        //4. If The Node Has A Name Then Print It Out
        if let validName = node.name{
             print("Node\(validName) Is A Child Node Of \(hitTestResultNode)")
        }

    }

}

如果您要查找特定 SCNNode 的子节点，请使用以下命令:

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

    //1. Get The Current Touch Location
    guard let currentTouchLocation = touches.first?.location(in: self.augmentedRealityView),

    //2. Get The Tapped Node From An SCNHitTest
    let hitTestResultNode = self.augmentedRealityView.hitTest(currentTouchLocation, options: nil).first?.node else { return }

    //3. If The Name Of The Nodes Is Equal To DetectableChildrenParent Then Get The Children
    if hitTestResultNode.name == "DetectableChildrenParent"{

        let childNodes = hitTestResultNode.childNodes

        print(childNodes)
    }

}

或者您也可以像这样简单地循环遍历 SCNHitTestResults:

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

    //1. Get The Current Touch Location
    guard let currentTouchLocation = touches.first?.location(in: self.augmentedRealityView) else { return }

    //2. Get The Results Of The SCNHitTest
    let hitTestResults = self.augmentedRealityView.hitTest(currentTouchLocation, options: nil)


    //3. Loop Through Them And Handle The Result
    for result in hitTestResults{

        print(result.node)
        print(result.node.childNodes)
    }


}

希望对你有帮助