创建一个球体的iOS迅速

Question

我有下面的代码： 类的ViewController：UIViewController的{

override func viewDidLoad() { 
    super.viewDidLoad() 

     let sceneView = SCNView(frame: self.view.frame) 
     self.view.addSubview(sceneView) 

     let scene = SCNScene() 
     sceneView.scene = scene 

     let camera = SCNCamera() 
     let cameraNode = SCNNode() 
     cameraNode.camera = camera 
     cameraNode.position = SCNVector3(x: -3.0, y: 3.0, z: 3.0) 

     let light = SCNLight() 
     light.type = SCNLightTypeOmni 
     let lightNode = SCNNode() 
     lightNode.light = light 
     lightNode.position = SCNVector3(x: 1.5, y: 1.5, z: 1.5) 

     let sphereGeometry = SCNSphere(radius: 5) 

     let sphereNode = SCNNode(geometry: sphereGeometry) 

     let constraint = SCNLookAtConstraint(target: sphereNode) 
     constraint.gimbalLockEnabled = true 
     cameraNode.constraints = [constraint] 


     scene.rootNode.addChildNode(lightNode) 
     scene.rootNode.addChildNode(cameraNode) 
     scene.rootNode.addChildNode(sphereNode) 

    } 

} 

然而，上述不显示任何它成功生成。

当我改变行;

let sphereGeometry = SCNSphere(radius: 5) 

来（创建多维数据集）：

let cubeGeometry = SCNBox(width: 1.0, height: 1.0, length: 1.0, chamferRadius: 0.0) 

我很困惑如何使球体出现。任何帮助将不胜感激:)

Answer 1

该代码实际上产生了一个球体。半径太大，相机恰好在球体内！

将半径从5更改为0.5就有诀窍！