如何在 Swiftui 中添加 3D 形状？答案

【问题标题】：How to add 3D shapes in Swift UI?如何在 Swiftui 中添加 3D 形状？
【发布时间】：2020-03-25 16:19:02
【问题描述】：

我想知道如何在 swift UI 中添加 3D 形状（例如球体）

我尝试添加一个场景并在 swift UI 中使用它，但我收到一条错误消息

//SceneKit

class myscene: SCNScene{
 override init(){
     super.init()
 }
 required init?(coder: NSCoder) {
     fatalError("init(coder: ) has not been implemented")
 }
}

//Swift UI 

struct ContentView: View {
 var body: some View {

     let sphere = SCNSphere(radius: 2.0)
     sphere.firstMaterial?.diffuse.contents = UIColor.blue
     let spherenode = SCNNode(geometry: sphere)
     spherenode.position = SCNVector3(x: 0.0, y: 3.0, z: 0.0)
 }
}

错误消息位于var body: some View { 行，内容如下：

Function declares an opaque return type, but has no return statements in its body from which to infer an underlying type

请帮我解决这个问题......

【问题讨论】：

标签： swift scenekit swiftui swift-playground swift5

【解决方案1】：

这是演示如何使用球体设置 SceneKit 场景的最简单代码。希望对您有所帮助。

import SwiftUI
import SceneKit

struct SceneKitView: UIViewRepresentable {
    func makeUIView(context: UIViewRepresentableContext<SceneKitView>) -> SCNView {
        let sceneView = SCNView()
        sceneView.scene = SCNScene()
        sceneView.allowsCameraControl = true
        sceneView.autoenablesDefaultLighting = true
        sceneView.backgroundColor = UIColor.black

        let sphere = SCNSphere(radius: 2.0)
        sphere.firstMaterial?.diffuse.contents = UIColor.blue
        let spherenode = SCNNode(geometry: sphere)
        spherenode.position = SCNVector3(x: 0.0, y: 3.0, z: 0.0)

        sceneView.scene?.rootNode.addChildNode(spherenode)
        return sceneView
    }

    func updateUIView(_ uiView: SCNView, context: UIViewRepresentableContext<SceneKitView>) {

    }

    typealias UIViewType = SCNView
}

struct DemoSceneKit: View {
    var body: some View {
        SceneKitView()
    }
}

struct DemoSceneKit_Previews: PreviewProvider {
    static var previews: some View {
        DemoSceneKit()
    }
}

【讨论】：