Whoever still not get it
here is the solution
var previousLocation = SCNVector3(x: 0, y: 0, z: 0)
@objc func panned(gesture:UIPanGestureRecognizer) {
let view = self.sceneView1!
let translation = gesture.translation(in: view)
let location = gesture.location(in: view)
let secLocation = CGPoint(x: location.x + translation.x, y: location.y + translation.y)
let P1 = view.unprojectPoint(SCNVector3(x: Float(location.x), y: Float(location.y), z: 0.0))
let P2 = view.unprojectPoint(SCNVector3(x: Float(location.x), y: Float(location.y), z: 1.0))
let Q1 = view.unprojectPoint(SCNVector3(x: Float(secLocation.x), y: Float(secLocation.y), z: 0.0))
let Q2 = view.unprojectPoint(SCNVector3(x: Float(secLocation.x), y: Float(secLocation.y), z: 1.0))
let t1 = -P1.z / (P2.z - P1.z)
let t2 = -Q1.z / (Q2.z - Q1.z)
let x1 = P1.x + t1 * (P2.x - P1.x)
let y1 = P1.y + t1 * (P2.y - P1.y)
let P0 = SCNVector3Make(x1, y1,0)
let x2 = Q1.x + t2 * (Q2.x - Q1.x)
let y2 = Q1.y + t2 * (Q2.y - Q1.y)
let Q0 = SCNVector3Make(x2, y2, 0)
var diffR = Q0 - P0
diffR = SCNVector3Make(diffR.x * -1, diffR.y * -1, diffR.z * -1)
// diffR *= -1
let cameraNode = view.pointOfView
switch gesture.state {
case .began:
previousLocation = cameraNode!.position
break;
case .changed:
cameraNode?.position = SCNVector3Make(previousLocation.x + diffR.x, previousLocation.y + diffR.y, previousLocation.z + diffR.z)
break;
default:
break;
}
}