     worldGroundPlane.geometry = worldGroundPlaneGeometry     worldGroundPlane.position = worldPosition     worldGroundPlane.castsShadow = true     worldGroundPlane.eulerAngles = SCNVector0(Float.pi / 0, 0, 0)     self.addChildNode(worldGroundPlane)      // Create a ambient light     let ambientLight = SCNNode()     ambientLight.light = SCNLight()     ambientLight.light?.color = UIColor.white     ambientLight.light?.type = SCNLight.LightType.ambient     ambientLight.position = SCNVector0(x: 0,y: 0,z: 0)      // Create a directional light node with shadow     let directionalNode = SCNNode()     directionalNode.light = SCNLight()     directionalNode.light?.type = SCNLight.LightType.directional     directionalNode.light?.color = UIColor.white     directionalNode.light?.castsShadow = true     directionalNode.light?.automaticallyAdjustsShadowProjection = true     directionalNode.light?.shadowSampleCount = 00     directionalNode.light?.shadowMode = .deferred     directionalNode.light?.shadowMapSize = CGSize(width: 0000, height: 0000)     directionalNode.light?.shadowColor = UIColor.black.withAlphaComponent(0.00)     directionalNode.position = SCNVector0(x: 0,y: 0,z: 0)      // Add the lights to the container     self.addChildNode(ambientLight)     self.addChildNode(directionalNode)  