polygon pattern generator

ViewController.swift

//
//  ViewController.swift
//  PolygonPattern
//
//  Created by MizushimaYusuke on 8/24/15.
//  Copyright (c) 2015 MizushimaYusuke. All rights reserved.
//

import UIKit
import SceneKit

class ViewController: UIViewController {

    weak var sceneView : SCNView?
    
    override func viewDidLoad() {
        super.viewDidLoad()
        setupScene()
        createPattern()
        createCamera()
        createLight()
    }

    func setupScene() {
        let sv = SCNView(frame: view.bounds)
        sv.scene = SCNScene()
        sv.allowsCameraControl = true
        view.addSubview(sv)
        sceneView = sv
    }
    
    func createPattern() {
        
        let g = SCNPyramid(width: 2, height: 3, length: 2)
        let hue = CGFloat(arc4random() % 10) * 0.1
        g.firstMaterial?.diffuse.contents = UIColor(hue: hue, saturation: 0.8, brightness: 1, alpha: 1)
        
        for i in 0..<50 {
            let x = Float(i % 5) - 2
            let z = Float(i / 5) - 4
            let node = SCNNode(geometry: g)
            node.name = "pattern"
            node.position = SCNVector3(x: x, y: 0, z: z)
            let wx = Float(arc4random() % 10) * 0.01 * Float(M_PI)
            let wy = Float(arc4random() % 10) * 0.01 * Float(M_PI)
            let wz = Float(arc4random() % 10) * 0.01 * Float(M_PI)
            node.transform = SCNMatrix4Rotate(node.transform, wx, 1, 0, 0)
            node.transform = SCNMatrix4Rotate(node.transform, wy, 0, 1, 0)
            node.transform = SCNMatrix4Rotate(node.transform, wz, 0, 0, 1)
            
            sceneView?.scene?.rootNode.addChildNode(node)
        }
    }

    func createCamera() {
        let camera = SCNNode()
        camera.camera = SCNCamera()
        camera.position = SCNVector3(x: 0, y: 7, z: 0)
        camera.rotation = SCNVector4(x: 1, y: 0, z: 0, w: -Float(M_PI) * 0.5)
        camera.camera?.usesOrthographicProjection = true
        camera.camera?.orthographicScale = 2
        
        sceneView?.scene?.rootNode.addChildNode(camera)
    }
    
    func createLight() {
        let light = SCNLight()
        light.type = SCNLightTypeSpot
        let node = SCNNode()
        node.light = light
        node.position = SCNVector3(x: 0, y: 50, z: 0)
        node.rotation = SCNVector4(x: 1, y: 0, z: 0, w: -Float(M_PI) * 0.5)
        sceneView?.scene?.rootNode.addChildNode(node)
        
        let light2 = SCNLight()
        light2.type = SCNLightTypeAmbient
        light2.color = UIColor(white: 0.5, alpha: 1)
        let node2 = SCNNode()
        node2.light = light2
        node2.position = SCNVector3(x: 0, y: 50, z: 0)
        node2.rotation = SCNVector4(x: 1, y: 0, z: 0, w: -Float(M_PI) * 0.5)
        sceneView?.scene?.rootNode.addChildNode(node2)
    }

    override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
        
        sceneView?.scene?.rootNode.childNodes
            .filter { ($0 as! SCNNode).name == "pattern" }
            .foreach { n in (n as! SCNNode).removeFromParentNode() }
        
        createPattern()
        
    }
    
}

extension Array {
    func foreach(doit:T -> Void) { for i in self {doit(i)} }
}