Ios 如何使applyForce（）转到场景中的特定点

我现在正在做一个游戏，目前我正在做一个自定义转换。为了简单起见，在我的转换中，每个节点都被指定为向右、向左、向上或向下滑动。我希望每个节点同时滑出屏幕。这是我的密码：

let slideAction : SKAction
var completed : Bool = false
let distance : CGFloat
let duration : NSTimeInterval = 3
//Slides the node in the direction specified
switch direction {
case .Left:
    distance = abs((child.position.x + child.frame.size.width / 2) - 0)
    slideAction = SKAction.applyForce[![enter image description here][1]][1](CGVector(dx: -distance / CGFloat(duration), dy: 0), duration: duration)
    child.runAction(slideAction, completion: {func Complete () { completed = true}})
    break
case .Right:
    distance = abs((child.position.x - child.frame.size.width / 2) - currentScene.frame.size.width)
    slideAction = SKAction.applyForce(CGVector(dx: distance / CGFloat(duration), dy: 0), duration: duration)
    child.runAction(slideAction, completion: {func Complete () { completed = true}})
    break
case .Up:
    distance = abs((child.position.y - child.frame.size.height / 2) - currentScene.frame.size.height)
    slideAction = SKAction.applyForce(CGVector(dx: 0, dy: distance / CGFloat(duration)), duration: duration)
    child.runAction(slideAction, completion: {func Complete () { completed = true}})
    break
case .Down:
    distance = abs((child.position.y + child.frame.size.height / 2) - 0)
    slideAction = SKAction.applyForce(CGVector(dx: 0, dy: -distance / CGFloat(duration)), duration: duration)
    child.runAction(slideAction, completion: {func Complete () { completed = true}})
    break
default: //The default is Shrink
    break
}

以下是gif以获取更多信息：

我想让它们同时从屏幕上消失。谢谢你，谢谢你的帮助

更新

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如果有人能告诉我applyForce函数的实际功能，那就不要这样了。

你看过函数的文档了吗？它解释了它在那里做什么。你能提供链接吗。我找不到。谷歌“sknode”和“applyForce”。这将是第一个链接。它不会出现。你能给我一个链接吗。