ball disk

ViewController.swift

//
//  ViewController.swift
//  BallDisk
//
//  Created by MizushimaYusuke on 8/21/15.
//  Copyright (c) 2015 MizushimaYusuke. All rights reserved.
//

import UIKit
import SceneKit

class ViewController: UIViewController, SCNSceneRendererDelegate {

    var state = 0
    weak var sceneView : SCNView?
    
    override func viewDidLoad() {
        super.viewDidLoad()
        setupScene()
        createDisk()
        createBall()
        createCamera()
    }
    
    func setupScene() {
        let sv = SCNView(frame: view.bounds)
        sv.backgroundColor = UIColor.darkGrayColor()
        sv.scene = SCNScene()
        sv.autoenablesDefaultLighting = true
        sv.allowsCameraControl = true
        sv.delegate = self
        view.addSubview(sv)
        
        sceneView = sv
    }

    func createDisk() {
        let disk = SCNNode()
        disk.name = "disk"
        disk.rotation = SCNVector4(x: 1, y: 0, z: 0, w: Float(M_PI) * 0.5)
        
        let backboard = SCNCylinder(radius: 5, height: 0.1)
        backboard.firstMaterial?.diffuse.contents = UIColor(hue: 0, saturation: 0.6, brightness: 0.7, alpha: 1)
        let backboardNode = SCNNode(geometry: backboard)
        disk.addChildNode(backboardNode)
        
        let edge = SCNTube(innerRadius: 4.8, outerRadius: 5, height: 1)
        edge.firstMaterial?.diffuse.contents = UIColor(hue: 0.25, saturation: 1, brightness: 0.7, alpha: 1)
        let edgeNode = SCNNode(geometry: edge)
        edgeNode.position = SCNVector3(x: 0, y: 0.5, z: 0)
        disk.addChildNode(edgeNode)
        
        for i in [SCNVector3(x: -2.5, y: 0.5, z: -2),
                    SCNVector3(x: 2, y: 0.5, z: 0),
                    SCNVector3(x: -1.7, y: 0.5, z: 1.5),
                    SCNVector3(x: 1.5, y: 0.5, z: 3)] {
            let b = SCNBox(width: 6, height: 1, length: 0.25, chamferRadius: 0)
            b.firstMaterial?.diffuse.contents = UIColor(hue: 0.25, saturation: 1, brightness: 0.7, alpha: 1)
            let bNode = SCNNode(geometry: b)
            bNode.position = i
            disk.addChildNode(bNode)
        }
        
        
        disk.physicsBody = SCNPhysicsBody.dynamicBody()
        disk.physicsBody?.physicsShape = SCNPhysicsShape(node: disk, options: [SCNPhysicsShapeTypeKey : SCNPhysicsShapeTypeConcavePolyhedron])
        disk.physicsBody?.angularVelocityFactor = SCNVector3(x: 0, y: 0, z: 1)
        disk.physicsBody?.angularDamping = 0.9
        
        let pin = SCNPhysicsHingeJoint(body: disk.physicsBody!, axis: SCNVector3(x: 0, y: 1, z: 0), anchor: disk.position)
        self.sceneView?.scene?.physicsWorld.addBehavior(pin)
        
        sceneView?.scene?.rootNode.addChildNode(disk)
    }

    func createBall() {
        let ball = SCNSphere(radius: 0.4)
        ball.firstMaterial?.diffuse.contents = UIColor.lightGrayColor()
        let ballNode = SCNNode(geometry: ball)
        ballNode.position = SCNVector3(x: 0, y: 4, z: 0.6)
        sceneView?.scene?.rootNode.addChildNode(ballNode)
        
        ballNode.physicsBody = SCNPhysicsBody.dynamicBody()
        ballNode.physicsBody?.velocityFactor = SCNVector3(x: 1, y: 1, z: 0)
    }
    
    func createCamera() {
        let camera = SCNNode()
        camera.camera = SCNCamera()
        camera.position = SCNVector3(x: 0, y: 0, z: 18)
        sceneView?.scene?.rootNode.addChildNode(camera)
    }
    
    override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
        sceneView?.playing = true
        if let touch = touches.first as? UITouch {
            let p = touch.locationInView(self.sceneView)
            self.state = p.x < CGRectGetMidX(self.view.bounds) ? 1 : 2
        }
    }
    
    override func touchesEnded(touches: Set<NSObject>, withEvent event: UIEvent) {
        self.state = 0
    }
    
    func renderer(aRenderer: SCNSceneRenderer, updateAtTime time: NSTimeInterval) {
        if let disk = self.sceneView?.scene?.rootNode.childNodeWithName("disk", recursively: false) {
            switch (self.state) {
            case 1:
                disk.physicsBody?.applyTorque(SCNVector4(x: 0, y: 0, z: 1, w: 50), impulse: false)
                break
            case 2:
                disk.physicsBody?.applyTorque(SCNVector4(x: 0, y: 0, z: 1, w: -50), impulse: false)
                break
            default:
                disk.physicsBody?.angularVelocity = SCNVector4Zero
                break
            }
        }
        
    }
}