Great & Powerful

import UIKit
import GLKit

public class StarWarsGLAnimator: NSObject,
UIViewControllerAnimatedTransitioning {

    public var duration: NSTimeInterval = 2
    public var spriteWidth: CGFloat = 8


    private var sprites: [Sprite] = []
    private var glContext: EAGLContext!
    private var effect: GLKBaseEffect!
    private var glView: GLKView!
    private var displayLink: CADisplayLink!
    private var lastUpdateTime: NSTimeInterval?
    private var startTransitionTime: NSTimeInterval!
    private var transitionContext:
UIViewControllerContextTransitioning!
    private var render: SpriteRender!

    public func transitionDuration(transitionContext:
UIViewControllerContextTransitioning?) ->
NSTimeInterval {
        return self.duration
    }

    public func animateTransition(transitionContext:
UIViewControllerContextTransitioning) {

        let containerView =
transitionContext.containerView()!
        let fromView =
transitionContext.viewControllerForKey(UITransitionCont
extFromViewControllerKey)!.view
        let toView =
transitionContext.viewControllerForKey(UITransitionCont
extToViewControllerKey)!.view

        containerView.addSubview(toView)
        containerView.sendSubviewToBack(toView)

        func randomFloatBetween(smallNumber: CGFloat,
and bigNumber: CGFloat) -> Float {
            let diff = bigNumber - smallNumber
            return Float(CGFloat(arc4random()) / 100.0
% diff + smallNumber)
        }

        self.glContext = EAGLContext(API: .OpenGLES2)
        EAGLContext.setCurrentContext(glContext)