SceneKit leaks when cloning a node

Question

I have asset loading and caching, defined as such:

class AssetLoader { fileprivate var rootNodes = Dictionary<String, SCNNode>() static let sharedInstance = AssetLoader() fileprivate init() { } func rootNode(_ named: String) -> SCNNode { if self.rootNodes[named] != nil { return self.rootNodes[named]!.clone() } else { let scene = SCNScene(named: "art.scnassets/\(named).scn") self.rootNodes[named] = scene!.rootNode return self.rootNodes[named]!.clone() } } } 

I use it to make the scene faster. I create assets from extensions as such:

 extension CAAnimation { class func animationWithScene(named: String) -> CAAnimation? { unowned let rootNode = AssetLoader.sharedInstance.rootNode(named) var animation: CAAnimation? rootNode.enumerateChildNodes({ (child, stop) in if child.animationKeys.count > 0 { animation = child.animation(forKey: child.animationKeys.first!) stop.initialize(to: true) } }) return animation } } extension SCNNode { class func nodeWithScene(named: String) -> SCNNode? { unowned let rootNode = AssetLoader.sharedInstance.rootNode(named) let node = SCNNode() for child in rootNode.childNodes { node.addChildNode(child) } node.eulerAngles = SCNVector3(x: Float(-M_PI_2), y: 0, z: 0) node.scale = SCNVector3Make(kMeshScale, kMeshScale, kMeshScale) return node } } 

The tools say that I console memory like crazy with every call to clone (). I tried to use the weak and not having the right, wherever I was, without the occurrence of failures, and this does not change anything. Somebody knows? Is this a bug in SceneKit?

thanks

Answer 1

If I understand correctly, you save your source nodes in the rootNodes dictionary of your AssetLoader and return a clone from the rootNode function.

My architecture is similar, and my problem was this: when I remove the cloned node from the scene tree, the memory will not be released. It's your problem?

I fixed the problem by adding the “upload” function to my singleton to reset the original nodes when deleting the cloned nodes from the scene tree. This fixed memory problems.

With code that would look something like this:

 func unloadRootNode(_ named: String) { rootNodes.removeValue(forKey: named) }