Ios 如何在AR工具包中旋转或缩放三维模型scn文件

这个类也呈现我的SCN文件

import UIKit
import ARKit

class SimpleViewController: UIViewController {

    @IBOutlet var sceneView: ARSCNView!

    override func viewDidLoad() {
        super.viewDidLoad()        
        sceneView.scene = SCNScene(named: "duck.scn", inDirectory: "models.scnassets/furniture")!
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        sceneView.session.run(ARWorldTrackingConfiguration())
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        sceneView.session.pause()
    }
}

---

但我知道如何旋转或缩放对象（

duck.scn

）文件。我希望用户可以与我的对象进行交互。

如果要缩放

SCNNode

，可以执行以下操作：

/// Scales An SCNNode
///
/// - Parameter gesture: UIPinchGestureRecognizer
@objc func scaleObject(gesture: UIPinchGestureRecognizer) {

    guard let nodeToScale = currentNode else { return }
    if gesture.state == .changed {

        let pinchScaleX: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.x))
        let pinchScaleY: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.y))
        let pinchScaleZ: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.z))
        nodeToScale.scale = SCNVector3Make(Float(pinchScaleX), Float(pinchScaleY), Float(pinchScaleZ))
        gesture.scale = 1

    }
    if gesture.state == .ended { }

}

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

    //1. Get The Current Touch Point
    guard let currentTouchPoint = touches.first?.location(in: self.augmentedRealityView),
        //2. Get The Next Feature Point Etc
        let hitTest = augmentedRealityView.hitTest(currentTouchPoint, types: .existingPlane).first else { return }

    //3. Convert To World Coordinates
    let worldTransform = hitTest.worldTransform

    //4. Set The New Position
    let newPosition = SCNVector3(worldTransform.columns.3.x, worldTransform.columns.3.y, worldTransform.columns.3.z)

    //5. Apply To The Node
    currentNode.simdPosition = float3(newPosition.x, newPosition.y, newPosition.z)

}

/// Rotates An SCNNode Around It's YAxis
///
/// - Parameter gesture: UIRotationGestureRecognizer
@objc func rotateNode(_ gesture: UIRotationGestureRecognizer){

    //1. Get The Current Rotation From The Gesture
    let rotation = Float(gesture.rotation)

    //2. If The Gesture State Has Changed Set The Nodes EulerAngles.y
    if gesture.state == .changed{

        currentNode.eulerAngles.y = currentAngleY + rotation
    }

    //3. If The Gesture Has Ended Store The Last Angle Of The Cube
    if(gesture.state == .ended) {
        currentAngleY = currentNode.eulerAngles.y

    }
}

其中当前节点指的是

SCNNode

如果要移动

SCNNode

，可以执行以下操作：

/// Scales An SCNNode
///
/// - Parameter gesture: UIPinchGestureRecognizer
@objc func scaleObject(gesture: UIPinchGestureRecognizer) {

    guard let nodeToScale = currentNode else { return }
    if gesture.state == .changed {

        let pinchScaleX: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.x))
        let pinchScaleY: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.y))
        let pinchScaleZ: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.z))
        nodeToScale.scale = SCNVector3Make(Float(pinchScaleX), Float(pinchScaleY), Float(pinchScaleZ))
        gesture.scale = 1

    }
    if gesture.state == .ended { }

}

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

    //1. Get The Current Touch Point
    guard let currentTouchPoint = touches.first?.location(in: self.augmentedRealityView),
        //2. Get The Next Feature Point Etc
        let hitTest = augmentedRealityView.hitTest(currentTouchPoint, types: .existingPlane).first else { return }

    //3. Convert To World Coordinates
    let worldTransform = hitTest.worldTransform

    //4. Set The New Position
    let newPosition = SCNVector3(worldTransform.columns.3.x, worldTransform.columns.3.y, worldTransform.columns.3.z)

    //5. Apply To The Node
    currentNode.simdPosition = float3(newPosition.x, newPosition.y, newPosition.z)

}

/// Rotates An SCNNode Around It's YAxis
///
/// - Parameter gesture: UIRotationGestureRecognizer
@objc func rotateNode(_ gesture: UIRotationGestureRecognizer){

    //1. Get The Current Rotation From The Gesture
    let rotation = Float(gesture.rotation)

    //2. If The Gesture State Has Changed Set The Nodes EulerAngles.y
    if gesture.state == .changed{

        currentNode.eulerAngles.y = currentAngleY + rotation
    }

    //3. If The Gesture Has Ended Store The Last Angle Of The Cube
    if(gesture.state == .ended) {
        currentAngleY = currentNode.eulerAngles.y

    }
}

然后你可以这样做：

/// Scales An SCNNode
///
/// - Parameter gesture: UIPinchGestureRecognizer
@objc func scaleObject(gesture: UIPinchGestureRecognizer) {

    guard let nodeToScale = currentNode else { return }
    if gesture.state == .changed {

        let pinchScaleX: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.x))
        let pinchScaleY: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.y))
        let pinchScaleZ: CGFloat = gesture.scale * CGFloat((nodeToScale.scale.z))
        nodeToScale.scale = SCNVector3Make(Float(pinchScaleX), Float(pinchScaleY), Float(pinchScaleZ))
        gesture.scale = 1

    }
    if gesture.state == .ended { }

}

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

    //1. Get The Current Touch Point
    guard let currentTouchPoint = touches.first?.location(in: self.augmentedRealityView),
        //2. Get The Next Feature Point Etc
        let hitTest = augmentedRealityView.hitTest(currentTouchPoint, types: .existingPlane).first else { return }

    //3. Convert To World Coordinates
    let worldTransform = hitTest.worldTransform

    //4. Set The New Position
    let newPosition = SCNVector3(worldTransform.columns.3.x, worldTransform.columns.3.y, worldTransform.columns.3.z)

    //5. Apply To The Node
    currentNode.simdPosition = float3(newPosition.x, newPosition.y, newPosition.z)

}

/// Rotates An SCNNode Around It's YAxis
///
/// - Parameter gesture: UIRotationGestureRecognizer
@objc func rotateNode(_ gesture: UIRotationGestureRecognizer){

    //1. Get The Current Rotation From The Gesture
    let rotation = Float(gesture.rotation)

    //2. If The Gesture State Has Changed Set The Nodes EulerAngles.y
    if gesture.state == .changed{

        currentNode.eulerAngles.y = currentAngleY + rotation
    }

    //3. If The Gesture Has Ended Store The Last Angle Of The Cube
    if(gesture.state == .ended) {
        currentAngleY = currentNode.eulerAngles.y

    }
}

如果您想直接与SCNScene交互（尽管我不相信ARKit），您可以使用以下方法：

var allowsCameraControl: Bool { get set }

据此：

如果将此属性设置为true，则SceneKit将创建摄影机节点并 处理鼠标或触摸事件，允许用户平移、缩放和 旋转他们的场景视图。（启用用户摄像头控制不起作用。） 修改场景图形或节点中已存在的摄影机对象 包含它们。）

例如：

 sceneView.scene = SCNScene(named: "duck.scn", inDirectory: "models.scnassets/furniture")!
 sceneView.allowsCameraControl = true;