radial ball

ViewController.swift

//
//  ViewController.swift
//  radialBall
//
//  Created by Mizushima Yusuke on 8/15/15.
//  Copyright (c) 2015 Yusuke Mizusima. All rights reserved.
//

import UIKit
import SceneKit

class ViewController: UIViewController, SCNSceneRendererDelegate {

    weak var sceneView : SCNView?
    var radialNode = SCNNode()
    var ballArr = Array<SCNNode>()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        setupScene()
        createGround()
        createCamera()
    }
    
    func setupScene() {
        let sv = SCNView(frame: view.bounds)
        sv.backgroundColor = UIColor(hue: 0.3, saturation: 0.1, brightness: 0.1, alpha: 1)
        sv.scene = SCNScene()
        sv.autoenablesDefaultLighting = true
        sv.allowsCameraControl = true
        sv.delegate = self
        view.addSubview(sv)
        
        self.sceneView = sv
    }
    
    func createGround() {
        let ground = SCNBox(width: 15, height: 0.1, length: 15, chamferRadius: 0)
        ground.firstMaterial?.diffuse.contents = UIColor(hue: 0.6, saturation: 0.5, brightness: 0.7, alpha: 1)
        let groundNode = SCNNode(geometry: ground)
        groundNode.position = SCNVector3(x: 0, y: -1, z: 0)
        
        groundNode.physicsBody = SCNPhysicsBody.staticBody()
        groundNode.physicsBody?.restitution = 0.8
        groundNode.physicsBody?.categoryBitMask = 1 << 2
        groundNode.physicsBody?.collisionBitMask = 1 << 1
        sceneView?.scene?.rootNode.addChildNode(groundNode)
    }

    func createBall() -> SCNNode {
        let ball = SCNSphere(radius: 0.2)
        ball.firstMaterial?.diffuse.contents = UIColor.whiteColor()
        let ballNode = SCNNode(geometry: ball)
        return ballNode
    }

    func createCamera() {
        let camera = SCNNode()
        camera.camera = SCNCamera()
        camera.position = SCNVector3(x: 0, y: 4, z: 10)
        camera.rotation = SCNVector4(x: 1, y: 0, z: 0, w: -0.4)
        sceneView?.scene?.rootNode.addChildNode(camera)
    }
    
    func runRadialAction() {
        let dw = Float(M_PI) / 5.0
        
        for i in 0...9 {
            let ball = createBall()
            ball.name = "\(i)"
            ball.rotation = SCNVector4(x: 0, y: 1, z: 0, w: Float(i) * dw)
            ball.physicsBody = SCNPhysicsBody.dynamicBody()
            ball.physicsBody?.categoryBitMask = 1 << 1
            ball.physicsBody?.collisionBitMask = 1 << 2
            ball.physicsBody?.restitution = 0.95
            sceneView?.scene?.rootNode.addChildNode(ball)
            
            let dx = 3 * cos(Float(i) * dw)
            let dz = 3 * sin(Float(i) * dw)
            ball.physicsBody?.applyForce(SCNVector3(x: dx, y: 8, z: dz), impulse: true)
            
            self.ballArr.append(ball)
        }
    }
    
    override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
        self.sceneView?.scene?.rootNode.addChildNode(radialNode)
        runRadialAction()
    }
    
    func renderer(aRenderer: SCNSceneRenderer, updateAtTime time: NSTimeInterval) {
        self.ballArr.foreach { i in
            let dot = SCNBox(width: 0.04, height: 0.04, length: 0.04, chamferRadius: 0)
            dot.firstMaterial?.diffuse.contents = UIColor(hue: CGFloat(i.name!.toInt()!) * 0.1, saturation: 0.4, brightness: 1, alpha: 1)
            let dotNode = SCNNode(geometry: dot)
            dotNode.position = i.presentationNode().position
            self.radialNode.addChildNode(dotNode)
            
            if i.position.y < 0 { i.removeFromParentNode() }
        }
    }
}

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