场景套件跟随相机

Question

我使用球作为球员的主要物理主体：

setup_Player () {
    playerGeometry = SCNSphere(radius: CGFloat(radius))
    playerGeometry.segmentCount = 64
    player = SCNNode(geometry: playerGeometry)
    player.geometry?.materials = [playerMaterial];
    player.position = SCNVector3(x: 1, y: 15, z:  0.5)
    let playerShape = SCNPhysicsShape(geometry: playerGeometry, options: nil)
    let playerBody = SCNPhysicsBody(type: .dynamic, shape: playerShape)
    player.physicsBody?.categoryBitMask = collisionRollingBall
    player.physicsBody?.collisionBitMask = collsionTarget
    player.physicsBody?.mass = 10
    player.physicsBody = playerBody
    scene.rootNode.addChildNode(player)
    }

编写代码来修复摄像机在我的播放器旁边的位置：

func setupCamera () {
    //create a main camera
    cameraNode = SCNNode()
    cameraNode.camera = SCNCamera()
    cameraNode.camera?.zFar = 100;
    cameraNode.position = SCNVector3Make(0, 0, 0)
    cameraNode.eulerAngles = SCNVector3Make(0, 0, 0)
    cameraNode.rotation  = SCNVector4Make(0, 1, 0, Float(-M_PI_4*0.75))
    scene.rootNode.addChildNode(cameraNode)
    //add a secondary camera to the player
    let frontCameraNode = SCNNode()
    frontCameraNode.position = SCNVector3Make(0, 15, 0)
    frontCameraNode.rotation  = SCNVector4Make(1, 0, 0, Float(-M_PI_4*2.2))
    frontCameraNode.camera = SCNCamera()
    frontCameraNode.camera?.zFar = 100
    player.addChildNode(frontCameraNode)
}

我只需要将摄像机位置冻结在一定距离处，就像在第三人称游戏中一样。

在这种情况下，相机获取球的物理属性并随之旋转。但我需要跟随球员和所有人，而不是以巨大的球速旋转......

如何将相机固定在播放器旁边，而不是继承其属性？任何想法如何忽略物理体的旋转？

提前谢谢。

Answer 1

您可以更新摄像机的位置，然后将其添加到场景中，而不是添加到播放器中。您应该在renderer(_:​update​At​Time:​)中的每一帧都执行此操作

https://developer.apple.com/reference/scenekit/scnscenerendererdelegate/1522937-renderer

frontCamerNode.position = SCNVector3(x: player.position.x, player.position.y, player.position.z - 10)

我认为还需要做更多的事情，例如相机的旋转等。但也许这为你指明了正确的方向。