Argthtjtr

When an image is detected, I add a node in front of it.

Image - what i need garantee

The node is this picture and in relation to this picture I add other nodes, one above (1) of the picture and another next (2). Node 1 always gets in the correct position, but node 2 sometimes gets in front of the image, which is wrong, and sometimes gets in the right position that it's like the photo.

Image - wrong

for anchor in sceneView.session.currentFrame!.anchors {

     let imageAnchor = anchor as! ARImageAnchor

     nodeInformation.position = SCNVector3Make(imageAnchor.transform.columns.3.x/100, imageAnchor.transform.columns.3.y/100 + 0.3, imageAnchor.transform.columns.3.z/100) //node 1

     nodeAuthorInformation.position = SCNVector3Make(imageAnchor.transform.columns.3.x/100 + 0.3, imageAnchor.transform.columns.3.y/100, imageAnchor.transform.columns.3.z/100) //node 2

This is the code that I'm using to set the initial position of my two nodes.

So i would like to know how i can garantee that my second node will stay always in the right position, that it is next to picture.

How I add the nodes:

let tappedNode = self.sceneView.hitTest(gesture.location(in: gesture.view), options: [:])



        if let result = tappedNode.first{

            nodeInformation.transform = result.modelTransform

            nodeAuthorInformation.transform = result.modelTransform

        }

        print("TAP PLACE = ", gesture.location(in: gesture.view))

        if !tappedNode.isEmpty{

            let node = tappedNode[0].node

            print("NODE TAP = ", node.position)

            let artPlane = SCNPlane(width: 0.3, height: 0.3)



            artPlane.firstMaterial?.diffuse.contents = arArtDetailsScene

            artPlane.firstMaterial?.isDoubleSided = true



            let planeNode = SCNNode(geometry: artPlane)

            planeNode.eulerAngles.x = .pi



            authorPlane = SCNPlane(width: 0.2, height: 0.3)

            authorPlane.firstMaterial?.diffuse.contents = arAuthorDetailsScene

            authorPlane.firstMaterial?.isDoubleSided = true



            let planeAuthorNode = SCNNode(geometry: authorPlane)

            planeAuthorNode.eulerAngles.x = .pi



            nodeInformation.addChildNode(planeNode)

            nodeAuthorInformation.addChildNode(planeAuthorNode)

            changeArtDetails(artId: artIndex + 1)



            sceneView.scene.rootNode.addChildNode(nodeInformation)

            sceneView.scene.rootNode.addChildNode(nodeAuthorInformation)

            if sceneView.session.currentFrame != nil {

                for anchor in sceneView.session.currentFrame!.anchors {

                    let imageAnchor = anchor as! ARImageAnchor

                    nodeInformation.position = SCNVector3Make(imageAnchor.transform.columns.3.x/100, imageAnchor.transform.columns.3.y/100 + 0.3, imageAnchor.transform.columns.3.z/100) // initial position node 1

                    nodeAuthorInformation.position = SCNVector3Make(imageAnchor.transform.columns.3.x/100 + 0.3, imageAnchor.transform.columns.3.y/100, imageAnchor.transform.columns.3.z/100) // initial position node 2

                }

            }

And I update the position of the node like this:

func renderer(_ renderer: SCNSceneRenderer, updateAtTime time: TimeInterval) {



    if sceneView.session.currentFrame != nil {

        for anchor in sceneView.session.currentFrame!.anchors {

            if let imageAnchor = anchor as? ARImageAnchor{

                DispatchQueue.main.async {



                    self.nodeInformation.position = SCNVector3Make(imageAnchor.transform.columns.3.x/100, imageAnchor.transform.columns.3.y/100 + 0.3, imageAnchor.transform.columns.3.z/100)

                    self.nodeAuthorInformation.position = SCNVector3Make(self.nodeInformation.position.x + 0.3, self.nodeInformation.position.y - 0.3, self.nodeInformation.position.z)//SCNVector3Make(imageAnchor.transform.columns.3.x/100 + 0.3, imageAnchor.transform.columns.3.y/100, imageAnchor.transform.columns.3.z/100)



                }

            } 

        }

    }

}

ARKit updates position of anchors, not nodes. You will need to provide a node with three custom nodes as children in ARSCNViewDelegate.renderer(_ renderer: SCNSceneRenderer, nodeFor anchor: ARAnchor) -> SCNNode? if anchor is ARImageAnchor instead of adding it manually to the scene.