Octahedron

import SceneKit

class GameViewController: NSViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        // новая сцена
        let scene = SCNScene()

        // создаём и добавляем камеру
        let 🎥 = SCNNode()
        🎥.camera = SCNCamera()
        scene.rootNode.addChildNode(🎥)

        // располагаем камеру
        🎥.position = SCNVector3(x: 0, y: 0, z: 15)

        // устанавливаем свет на сцене
        let lightNode0 = SCNNode()
        lightNode0.light = SCNLight()
        lightNode0.light!.type = .omni
        lightNode0.position = SCNVector3(x: 0, y: 10, z: 10)
        scene.rootNode.addChildNode(lightNode0)

        let lightNode1 = SCNNode()
        lightNode1.light = SCNLight()
        lightNode1.light!.type = .omni
        lightNode1.position = SCNVector3(5, -10, 0)
        scene.rootNode.addChildNode(lightNode1)

        let scnView = self.view as! SCNView
        scnView.scene = scene

        // позволяем пользователю управлять камерой
        scnView.allowsCameraControl = true

        // Настраиваем цвета фона
        scnView.backgroundColor = NSColor.black

        createOctahedron()
    }

    func createOctahedron() {
        let vertices: [SCNVector3] = [
            SCNVector3(0, 1, 0),
            SCNVector3(-0.5, 0, 0.5),
            SCNVector3(0.5, 0, 0.5),
            SCNVector3(0.5, 0, -0.5),
            SCNVector3(-0.5, 0, -0.5),
            SCNVector3(0, -1, 0)
        ]

        let source = SCNGeometrySource(vertices: vertices)

        let indices: [UInt16] = [
            0, 1, 2,
            2, 3, 0,
            3, 4, 0,
            4, 1, 0,
            1, 5, 2,
            2, 5, 3,
            3, 5, 4,
            4, 5, 1
        ]

        let element = SCNGeometryElement(indices: indices, primitiveType: .triangles)
        let geometry = SCNGeometry(sources: [source], elements: [element])
        let node = SCNNode(geometry: geometry)

        node.geometry?.firstMaterial?.diffuse.contents = NSColor.green // назначаем цвет октаэдру

        let scnView = self.view as! SCNView
        scnView.scene?.rootNode.addChildNode(node)

        let rotateAction = SCNAction.repeatForever(SCNAction.rotateBy(x: 0, y: .pi, z: 0, duration: 5))
        node.runAction(rotateAction)
    }
}