How to place 3D model using ARKit iOS 11 with some

问题:

I am working on an Augmented Reality iOS app for which i am using ARKIT of iOS 11 beta. I am using ARSCNView(SceneKit) to render my .scn object. I have followed the sample given by apple in order to create an ARSession(https://developer.apple.com/sample-code/wwdc/2017/PlacingObjects.zip). Is it possible to place the 3D model with custom background instead of camera?

Like user can select the background color or can provide custom 2D photos as background?

回答1:

Your view has a scene property where you can set the background to a color or an image:

 view.scene.background.contents = UIColor.red

 let myImage: UIImage = ... 
 view.scene.background.contents = myImage

回答2:

I use shake motion callback of UIKit to change background contents. As @yaali said, CameraContents is used to store camera contents. Notice that we can't get background.contents if the camera has not launched, for example on viewWillAppear. I guess ARKit set the AVCaptureVideoPreviewLayer to ARSCNView.scene.background.cocntents.

    override func motionBegan(_ motion: UIEventSubtype, with event: UIEvent?) {
        if CameraContents == nil {
            CameraContents = sceneView.scene.background.contents;
            return
        }
        if cameraBackGround == true {
            sceneView.scene.background.contents = "Background_sky.png"
        }else{
            sceneView.scene.background.contents = CameraContents
        }
        cameraBackGround = !cameraBackGround

    }