施加力后如何获得当前SCNnode位置

Question

我使用以下方法对场景中的SCNnode施加恒定力，

func applyForceToDrone(powerApply: Double, isHovering: Bool, gravity : SCNVector3) {

let nodo = arrayDrone[0] // load the first drone in the scene
guard let lhBlade = nodo.childNode(withName: "Rotor_L_2", recursively: true) else {fatalError()}
guard let rhBlade = nodo.childNode(withName: "Rotor_R_2", recursively: true) else {fatalError()}
if isHovering == true {
print("x gravity = (gravity.x), (gravity.y) (gravity.z)")
let force = SCNVector3(gravity.x, abs(gravity.y), gravity.z)
nodo.physicsBody?.applyForce(force, asImpulse: false)
} else {
print("apply power  (powerApply)")
let positionBladeLH = lhBlade.position
let positionBladeRH = rhBlade.position
let force = SCNVector3(0, powerApply, 0)
nodo.physicsBody?.applyForce(force, at: positionBladeLH, asImpulse: false)
nodo.physicsBody?.applyForce(force, at: positionBladeRH, asImpulse: false)

let alt = nodo.position.y // position is wrong ... is always the starting position
print(alt)
}
}

我在渲染方法中使用这个函数来飞行我的无人机。

func renderer(_ renderer: SCNSceneRenderer, updateAtTime time: TimeInterval) {}

我想在每次施加力时读取节点的当前位置。

当渲染应用力时，我如何获得更新位置。

I tried with:

let alt = nodo.position.y

但是它总是给我节点的起始位置，而不是施加力后的位置

感谢

Answer 1

像这样使用节点的表示对象:

不是

nodo.position.y

使用

nodo.presentation.position.y // local space

或

nodo.presentation.worldPosition.y // world space