我正在处理具有已改变的枢轴和位置的子节点。我发现了很多SCNNode转换主题,但似乎没有一个代表我的情况。
我有六个球:(不能发布超过2个链接,图片位于i.stack.imgur.com/v3Lc4.png)
我选择前四个,调整枢轴,调整位置(以对抗枢轴平移效果),然后旋转。这是我使用的代码:
//core code
let fourBalls = SCNNode()
for i in 1...4
{
let ball = scene.rootNode.childNode(withName: "b" + String(i), recursively: false)!
ball.removeFromParentNode()
fourBalls.addChildNode(ball)
}
scene.rootNode.addChildNode(fourBalls)
//adjust the pivot of the fourBalls node
fourBalls.pivot = SCNMatrix4MakeTranslation(-1.5, 0.5, -5)
//fix the position
fourBalls.position = SCNVector3Make(-1.5, 0.5, -5)
//rotate
let action = SCNAction.rotateBy(x: 0, y: 0, z: CGFloat(M_PI_2), duration: 2)
fourBalls.run(action)
它做得很好:
现在,我需要将fourBalls子节点释放回rootNode,我使用这个代码作为完成块:
//core problem
//how to release the node with the transform?
for node in fourBalls.childNodes
{ node.transform = node.worldTransform
node.removeFromParentNode()
self.scene.rootNode.addChildNode(node)
}
问题出现了,我错误地发布了它们:
所以我的问题是,如何使用正确的pivot,position和transform属性将子节点释放到rootNode? p>
这是我想要尝试的完整GameViewController.swift:
import SceneKit
class GameViewController: UIViewController {
let scene = SCNScene()
override func viewDidLoad() {
super.viewDidLoad()
let ball1 = SCNSphere(radius: 0.4)
let ball2 = SCNSphere(radius: 0.4)
let ball3 = SCNSphere(radius: 0.4)
let ball4 = SCNSphere(radius: 0.4)
let ball5 = SCNSphere(radius: 0.4)
let ball6 = SCNSphere(radius: 0.4)
ball1.firstMaterial?.diffuse.contents = UIColor.purple()
ball2.firstMaterial?.diffuse.contents = UIColor.white()
ball3.firstMaterial?.diffuse.contents = UIColor.cyan()
ball4.firstMaterial?.diffuse.contents = UIColor.green()
ball5.firstMaterial?.diffuse.contents = UIColor.black()
ball6.firstMaterial?.diffuse.contents = UIColor.blue()
let B1 = SCNNode(geometry: ball1)
B1.position = SCNVector3(x:-2,y:1,z:-5)
scene.rootNode.addChildNode(B1)
B1.name = "b1"
let B2 = SCNNode(geometry: ball2)
B2.position = SCNVector3(x:-1,y:1,z:-5)
scene.rootNode.addChildNode(B2)
B2.name = "b2"
let B3 = SCNNode(geometry: ball3)
B3.position = SCNVector3(x:-2,y:0,z:-5)
scene.rootNode.addChildNode(B3)
B3.name = "b3"
let B4 = SCNNode(geometry: ball4)
B4.position = SCNVector3(x:-1,y:0,z:-5)
scene.rootNode.addChildNode(B4)
B4.name = "b4"
let B5 = SCNNode(geometry: ball5)
B5.position = SCNVector3(x:-2,y:-1,z:-5)
scene.rootNode.addChildNode(B5)
B5.name = "b5"
let B6 = SCNNode(geometry: ball6)
B6.position = SCNVector3(x:-1,y:-1,z:-5)
scene.rootNode.addChildNode(B6)
B6.name = "b6"
let cameraNode = SCNNode()
cameraNode.camera = SCNCamera()
cameraNode.position = SCNVector3Make(-1.5,0,2)
scene.rootNode.addChildNode(cameraNode)
// create and add an ambient light to the scene
let ambientLightNode = SCNNode()
ambientLightNode.light = SCNLight()
ambientLightNode.light!.type = SCNLightTypeAmbient
ambientLightNode.light!.color = UIColor.yellow()
scene.rootNode.addChildNode(ambientLightNode)
let scnView = self.view as! SCNView
scnView.scene = scene
scnView.allowsCameraControl = false
scnView.backgroundColor = UIColor.orange()
//core code
let fourBalls = SCNNode()
for i in 1...4
{
let ball = scene.rootNode.childNode(withName: "b" + String(i), recursively: false)!
ball.removeFromParentNode()
fourBalls.addChildNode(ball)
}
scene.rootNode.addChildNode(fourBalls)
//adjust the pivot of the fourBalls node
fourBalls.pivot = SCNMatrix4MakeTranslation(-1.5, 0.5, -5)
//fix the position
fourBalls.position = SCNVector3Make(-1.5, 0.5, -5)
//rotate
let action = SCNAction.rotateBy(x: 0, y: 0, z: CGFloat(M_PI_2), duration: 2)
fourBalls.run(action, completionHandler:
{
//core problem
for node in fourBalls.childNodes
{
node.transform = node.worldTransform
node.removeFromParentNode()
self.scene.rootNode.addChildNode(node)
}
})
}
override func shouldAutorotate() -> Bool {
return true
}
override func prefersStatusBarHidden() -> Bool {
return true
}
override func supportedInterfaceOrientations() -> UIInterfaceOrientationMask {
if UIDevice.current().userInterfaceIdiom == .phone {
return .allButUpsideDown
} else {
return .all
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Release any cached data, images, etc that aren't in use.
}
}
答案 0 :(得分:0)
SCNActions直接更新表示树,而不是模型树,这可能在2014 WWDC video (skip to 16:38)中得到了最好的解释。这意味着在整个动画中,每个动画节点的当前变换仅可从presentationNode
获得。如果我们从这里获得转换,你的代码就可以工作。
为Swift 2 backport道歉...
//rotate
let action = SCNAction.rotateByX(0, y: 0, z: CGFloat(M_PI_2), duration: 2)
fourBalls.runAction(action, completionHandler: {
//core problem
for node in fourBalls.childNodes
{
node.transform = node.presentationNode.worldTransform
node.removeFromParentNode()
self.scene.rootNode.addChildNode(node)
}
})
TBH我到达完成处理程序时期待node.worldTransform == node.presentationNode.worldTransform
。