Changing scene view lighting model programmatically

Question

I am loading a 3D model using SCNScene in SwiftUI, my object looks better in lambert or phong shading. I am trying to change the lighting model like this:

var scene: SCNScene? {
        let scene = SCNScene(named: "model.usdz")
        scene?.rootNode.geometry?.firstMaterial?.lightingModel = .lambert
        scene?.rootNode.scale = SCNVector3(scale, scale, scale)
        return scene
    }

and then load the scene in body:

var body: some View {
    
            SceneView(
                scene: scene,
                pointOfView: cameraNode,
                options: [.allowsCameraControl, .autoenablesDefaultLighting]
            )
}

but changing the lighting model doesn't affect the model, or even tried manually in the scene kit editor but still no luck, any solution would be great.

@Asperi I logged and the material is nil! why? I have diffuse material — Mc.Lover, Jun 30 '22 at 15:28

score 0 · Answer 1 · answered Jun 30 '22 at 17:12

Your code, as far as I can see, changes the Lighting Model of the RootNode (this changes nothing, because the rootnode itself stays invisible). To Change the Lighting Model of your T-Rex-Scull Model, you must fetch the exact Node containing the geometry of that Model, which is usually a childNode or a child of a childNode. This should work then.

Changing scene view lighting model programmatically

1 Answers1