I added a button to my SceneView to delete placed images on a wall:
@IBAction func reset(_ sender: Any) {
sceneView.scene.rootNode.enumerateChildNodes { (node, _) in node.removeFromParentNode()
}
}
It's working fine but after some seconds the app crashed with following warning:
com.apple.scenekit.scnview-renderer (14): Fatal error: Unexpectedly found nil while unwrapping an Optional value
In this part of my code appears the error:
func update(anchor: ARPlaneAnchor) {
planeGeometry.width = CGFloat(anchor.extent.x);
planeGeometry.height = CGFloat(anchor.extent.z);
position = SCNVector3Make(anchor.center.x, 0, anchor.center.z);
let planeNode = self.childNodes.first!
planeNode.physicsBody = SCNPhysicsBody(type: .static, shape: SCNPhysicsShape(geometry: self.planeGeometry, options: nil))
}
What did i do wrong?
Here let planeNode = self.childNodes.first!
you force unwrapping the value. After removing all nodes from childNodes
array, it will become empty. Use if let
if let planeNode = self.childNodes.first{
planeNode.physicsBody = SCNPhysicsBody(type: .static, shape: SCNPhysicsShape(geometry: self.planeGeometry, options: nil))
}