如何使 SceneView 的背景透明?

How can I make SceneView's background transparent?

我想打开一个 3D 模型并使其背景透明,这样我就可以看到 SceneView 后面的 UI。我试过这段代码,但是sceneView变成了白色,不透明。


struct ModelView: View {
    var body: some View {
        ZStack {
            Text("Behind Text Behind Text Behind Text")
            SceneView(
                scene: { () -> SCNScene in
                    let scene = SCNScene()
                    scene.background.contents = UIColor.clear
                    return scene
                }(),
                pointOfView: { () -> SCNNode in
                    let cameraNode = SCNNode()
                    cameraNode.camera = SCNCamera()
                    cameraNode.position = SCNVector3(x: 0, y: 0, z: 10)
                    return cameraNode
                }(),
                options: [
                    .allowsCameraControl,
                    .temporalAntialiasingEnabled,
                ]
            )
        }
    }
}

我使用 XCode 12.5 和 IPhone 8.

编辑 1:

感谢下面的评论,我决定尝试新的方法,但它们仍然不起作用。

方法 #1

首先,我尝试通过 UIViewRepresentable:

使用 SCNView 创建一个 MySceneView
struct MySceneView: UIViewRepresentable {
    typealias UIViewType = SCNView
    typealias Context = UIViewRepresentableContext<MySceneView>

    func updateUIView(_ uiView: UIViewType, context: Context) {}
    func makeUIView(context: Context) -> UIViewType {
        let view = SCNView()
        view.allowsCameraControl = true
        view.isTemporalAntialiasingEnabled = true
        view.autoenablesDefaultLighting = true
        view.scene = MySceneView.scene
        return view
    }
    
    static let scene: SCNScene = {
        let scene = SCNScene(named: "art.scnassets/man.obj")!
        scene.background.contents = UIColor.clear
        let cameraNode = SCNNode()
        cameraNode.camera = SCNCamera()
        cameraNode.position = SCNVector3(x: 0, y: 0, z: 10)
        scene.rootNode.addChildNode(cameraNode)
        return scene
    }()
}

方法#2 我尝试使用 SpriteView,这里是代码:

        ZStack {
            Text("Behind Text Behind Text Behind Text")
            SpriteView(scene: { () -> SKScene in
                let scene = SKScene()
                scene.backgroundColor = UIColor.clear
                let model = SK3DNode(viewportSize: .init(width: 200, height: 200))
                model.scnScene = MySceneView.scene
                scene.addChild(model)
                return scene
            }(), options: [.allowsTransparency])
}

更新:

一个更简单的解决方案是使用 UIViewRepresentable,创建 SCNView 并将 backgroundColor 设置为 clear

旧:

谢谢 George_E,您的想法与 SpriteKit 完美结合。这是代码:

SpriteView(scene: { () -> SKScene in
    let scene = SKScene()
    scene.backgroundColor = UIColor.clear
    let model = SK3DNode(viewportSize: .init(width: 200, height: 200))
    model.scnScene = {
        let scene = SCNScene(named: "art.scnassets/man.obj")!
        scene.background.contents = UIColor.clear
        let cameraNode = SCNNode()
        cameraNode.camera = SCNCamera()
        cameraNode.position = SCNVector3(x: 0, y: 0, z: 10)
        scene.rootNode.addChildNode(cameraNode)
        return scene
    }()
    scene.addChild(model)
    return scene
}(), options: [.allowsTransparency])

使用 SwiftUI:

SwiftUI 中使用 SpriteView 略有不同。

要在SwiftUI中实现透明的SpriteView,必须使用'options'参数:

  1. 使用清晰的背景(视图和场景)配置您的 SKScene
  2. 使用正确的选项配置您的 SpriteView
// 1. configure your scene in 'didMove'
override func didMove(to view: SKView) {
    self.backgroundColor = .clear
    view.backgroundColor = .clear
}

最重要的是:

// 2. configure your SpriteView with 'allowsTranspanency'
SpriteView(scene: YourSKScene(), options: [.allowsTransparency])