Incorrect camera position playing 360 degree video using SceneKit and CoreMotion

Question

I play with a 360 degree video player using SpriteKit, SceneKit and CoreMotion. The player is still working, but the video is always increasing. It seems that the camera position is not at (0,0,0), but somehow wrong on the Z axis. Unfortunately, I did not find a way to adjust this. To reproduce the behavior, simply tap the screen when the video is playing and press the zoom out button. This allows you to control the camera using gestures, double-tap returns to control the camera using the device.

import UIKit
import SceneKit
import CoreMotion
import SpriteKit
import AVFoundation

class Video360VC: UIViewController {
let motionManager = CMMotionManager()
let cameraNode = SCNNode()
@IBOutlet weak var sceneView: SCNView!

@IBAction func exitBtnClicked(_ sender: Any) {
performSegueToReturnBack()
}

func createSphereNode(material: AnyObject?) -> SCNNode {
    let sphere = SCNSphere(radius: 20.0)
    sphere.firstMaterial!.isDoubleSided = true
    sphere.firstMaterial!.diffuse.contents = material
    let sphereNode = SCNNode(geometry: sphere)
    sphereNode.position = SCNVector3Make(0,0,0)
    sphereNode.rotation = SCNVector4Make(1, 0, 0, Float.pi)
    return sphereNode
}

func configureScene(node sphereNode: SCNNode) {
    // Set the scene
    let scene = SCNScene()
    sceneView.scene = scene
    sceneView.showsStatistics = true
    sceneView.allowsCameraControl = true

    // Camera, ...
    cameraNode.camera = SCNCamera()
    cameraNode.position = SCNVector3Make(0, 0, 0)
    scene.rootNode.addChildNode(sphereNode)
    scene.rootNode.addChildNode(cameraNode)
}

func startCameraTracking() {
    motionManager.deviceMotionUpdateInterval = 1.0 / 60.0
    motionManager.startDeviceMotionUpdates(to: OperationQueue.main) {
        [weak self](data: CMDeviceMotion?, error: Error?) in
        guard let data = data else { return }
        let attitude: CMAttitude = data.attitude

        self?.cameraNode.eulerAngles = SCNVector3Make(-   Float(attitude.roll + Double.pi/2), Float(attitude.yaw), -Float(attitude.pitch))
    }
}

override func viewDidLoad() {
    super.viewDidLoad()

    guard let fileURL = Bundle.main.url(forResource: "360Test2", withExtension: "mp4") else {
        print("Video File not found")
        return
    }

    let player = AVPlayer(url: fileURL)
    let videoNode = SKVideoNode(avPlayer: player)
    let size = CGSize(width: 1280, height: 720)
    videoNode.size = size
    videoNode.position = CGPoint(x: size.width/2, y: size.height/2)

    let spriteScene = SKScene(size: size)
    spriteScene.scaleMode = .resizeFill
    spriteScene.addChild(videoNode)

    let sphereNode = createSphereNode(material:spriteScene)
    configureScene(node: sphereNode)
    guard motionManager.isDeviceMotionAvailable else {
        fatalError("Device motion is not available")
    }
    startCameraTracking()
    player.play()
}

override func viewWillAppear(_ animated: Bool) {
    self.sceneView.play(self)
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
}
}

I used this video for testing, which can also be downloaded. Many thanks!

Answer 1

, , Field of View. , zoomed, . FOV , , 90 .