progress commit for MotionCoreAnimationViewContext

55e5e287 · Daniel Dahan · 7b809595 · 55e5e287 · 55e5e287 · 55e5e287
Commit 55e5e287 authored Dec 12, 2017 by Daniel Dahan
8 changed files
--- a/Motion.xcodeproj/project.pbxproj
+++ b/Motion.xcodeproj/project.pbxproj
@@ -13,7 +13,7 @@
 		965FE9671FDD99800098BDD0 /* Motion+Start.swift in Sources */ = {isa = PBXBuildFile; fileRef = 965FE9661FDD99800098BDD0 /* Motion+Start.swift */; };
 		965FE9691FDDA1F20098BDD0 /* MotionViewOrderStrategy.swift in Sources */ = {isa = PBXBuildFile; fileRef = 965FE9681FDDA1F20098BDD0 /* MotionViewOrderStrategy.swift */; };
 		965FE96B1FDDA4EA0098BDD0 /* BaseMotionPreprocessor.swift in Sources */ = {isa = PBXBuildFile; fileRef = 965FE96A1FDDA4EA0098BDD0 /* BaseMotionPreprocessor.swift */; };
-		965FE96D1FDDA6400098BDD0 /* BaseMotionAnimator.swift in Sources */ = {isa = PBXBuildFile; fileRef = 965FE96C1FDDA6400098BDD0 /* BaseMotionAnimator.swift */; };
+		965FE96D1FDDA6400098BDD0 /* MotionCoreAnimator.swift in Sources */ = {isa = PBXBuildFile; fileRef = 965FE96C1FDDA6400098BDD0 /* MotionCoreAnimator.swift */; };
 		965FE96F1FDEFA8B0098BDD0 /* Motion+Animate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 965FE96E1FDEFA8B0098BDD0 /* Motion+Animate.swift */; };
 		96E409651F24F7370015A2B5 /* MotionAnimator.swift in Sources */ = {isa = PBXBuildFile; fileRef = 96E4093D1F24F7370015A2B5 /* MotionAnimator.swift */; };
 		96E409661F24F7370015A2B5 /* MotionAnimatorViewContext.swift in Sources */ = {isa = PBXBuildFile; fileRef = 96E4093E1F24F7370015A2B5 /* MotionAnimatorViewContext.swift */; };
@@ -91,7 +91,7 @@
 		965FE9661FDD99800098BDD0 /* Motion+Start.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Motion+Start.swift"; sourceTree = "<group>"; };
 		965FE9681FDDA1F20098BDD0 /* MotionViewOrderStrategy.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MotionViewOrderStrategy.swift; sourceTree = "<group>"; };
 		965FE96A1FDDA4EA0098BDD0 /* BaseMotionPreprocessor.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BaseMotionPreprocessor.swift; sourceTree = "<group>"; };
-		965FE96C1FDDA6400098BDD0 /* BaseMotionAnimator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BaseMotionAnimator.swift; sourceTree = "<group>"; };
+		965FE96C1FDDA6400098BDD0 /* MotionCoreAnimator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MotionCoreAnimator.swift; sourceTree = "<group>"; };
 		965FE96E1FDEFA8B0098BDD0 /* Motion+Animate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Motion+Animate.swift"; sourceTree = "<group>"; };
 		96C98DD11E424AB000B22906 /* Motion.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Motion.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		96E4093D1F24F7370015A2B5 /* MotionAnimator.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = MotionAnimator.swift; sourceTree = "<group>"; };
@@ -183,7 +183,7 @@
 			isa = PBXGroup;
 			children = (
 				96E4093D1F24F7370015A2B5 /* MotionAnimator.swift */,
-				965FE96C1FDDA6400098BDD0 /* BaseMotionAnimator.swift */,
+				965FE96C1FDDA6400098BDD0 /* MotionCoreAnimator.swift */,
 				96E4093E1F24F7370015A2B5 /* MotionAnimatorViewContext.swift */,
 				96E4093F1F24F7370015A2B5 /* MotionCoreAnimationViewContext.swift */,
 				96E409401F24F7370015A2B5 /* MotionHasInsertOrder.swift */,
@@ -332,7 +332,7 @@
 				965FE9631FDCCE030098BDD0 /* Motion+Complete.swift in Sources */,
 				96E4097D1F24F7370015A2B5 /* MotionPlugin.swift in Sources */,
 				96E409681F24F7370015A2B5 /* MotionHasInsertOrder.swift in Sources */,
-				965FE96D1FDDA6400098BDD0 /* BaseMotionAnimator.swift in Sources */,
+				965FE96D1FDDA6400098BDD0 /* MotionCoreAnimator.swift in Sources */,
 				96E4096E1F24F7370015A2B5 /* Motion+CG.swift in Sources */,
 				96E409851F24F7370015A2B5 /* MatchPreprocessor.swift in Sources */,
 				96E409861F24F7370015A2B5 /* MotionPreprocessor.swift in Sources */,

--- a/Sources/Animator/MotionAnimatorViewContext.swift
+++ b/Sources/Animator/MotionAnimatorViewContext.swift
@@ -30,17 +30,20 @@ import UIKit
 internal class MotionAnimatorViewContext {
    /// An optional reference to a MotionAnimator.
-    var animator: BaseMotionAnimator?
+    var animator: MotionCoreAnimator?
    /// A reference to the snapshot UIView.
    var snapshot: UIView
-    /// Animation duration time.
-    var duration: TimeInterval = 0
    /// The animation target state.
    var targetState: MotionTransitionState
+    /// A boolean indicating if the view is appearing.
+    var isAppearing: Bool
+    /// Animation duration time.
+    var duration: TimeInterval = 0
    /// The computed current time of the snapshot layer.
    var currentTime: TimeInterval {
        return snapshot.layer.convertTime(CACurrentMediaTime(), from: nil)
@@ -56,11 +59,13 @@ internal class MotionAnimatorViewContext {
     - Parameter animator: A MotionAnimator.
     - Parameter snapshot: A UIView.
     - Parameter targetState: A MotionTransitionState.
+     - Parameter isAppearing: A Boolean.
     */
-    required init(animator: BaseMotionAnimator, snapshot: UIView, targetState: MotionTransitionState) {
+    required init(animator: MotionCoreAnimator, snapshot: UIView, targetState: MotionTransitionState, isAppearing: Bool) {
        self.animator = animator
        self.snapshot = snapshot
        self.targetState = targetState
+        self.isAppearing = isAppearing
    }
    /// Cleans the context.
@@ -86,8 +91,11 @@ internal class MotionAnimatorViewContext {
     - Parameter at elapsedTime: A TimeInterval.
     - Parameter isReversed: A boolean to reverse the animation 
     or not.
+     - Returns: A TimeInterval.
     */
-    func resume(at elapsedTime: TimeInterval, isReversed: Bool) {}
+    func resume(at elapsedTime: TimeInterval, isReversed: Bool) -> TimeInterval {
+        return 0
+    }
    /**
     Moves the animation to the given elapsed time.
@@ -106,5 +114,8 @@ internal class MotionAnimatorViewContext {
     - Parameter isAppearing: A boolean value whether the view
     is appearing or not.
     */
-    func startAnimations(isAppearing: Bool) {}
+    @discardableResult
+    func startAnimations() -> TimeInterval {
+        return 0
+    }
 }
--- a/Sources/Animator/MotionCoreAnimationViewContext.swift
+++ b/Sources/Animator/MotionCoreAnimationViewContext.swift
@@ -35,6 +35,9 @@ internal class MotionCoreAnimationViewContext: MotionAnimatorViewContext {
    /// A reference to the animation timing function.
    fileprivate var timingFunction = CAMediaTimingFunction.standard
+    /// Current animations.
+    var animations = [(CALayer, String, CAAnimation)]()
    /// Layer which holds the content.
    fileprivate var contentLayer: CALayer? {
        return snapshot.layer.sublayers?.get(0)
@@ -68,40 +71,60 @@ internal class MotionCoreAnimationViewContext: MotionAnimatorViewContext {
    }
    override func apply(state: MotionTransitionState) {
-        let ts = viewState(targetState: state)
+        let targetState = viewState(targetState: state)
-        for (key, targetValue) in ts {
+        for (key, targetValue) in targetState {
            if nil == transitionStates[key] {
                let current = currentValue(for: key)
                transitionStates[key] = (current, current)
            }
-            animate(key: key, beginTime: 0, fromValue: targetValue, toValue: targetValue)
+            let oldAnimations = animations
+            animations = []
+            animate(key: key, beginTime: 0, duration: 100, fromValue: targetValue, toValue: targetValue)
+            animations = oldAnimations
        }
    }
-    override func resume(at elapsedTime: TimeInterval, isReversed: Bool) {
+    override func resume(at elapsedTime: TimeInterval, isReversed: Bool) -> TimeInterval {
        for (key, (fromValue, toValue)) in transitionStates {
-            transitionStates[key] = (currentValue(for: key), !isReversed ? toValue : fromValue)
+            transitionStates[key] = (currentValue(for: key), isReversed ? fromValue : toValue)
        }
-        targetState.duration = isReversed ? elapsedTime - targetState.delay : duration - elapsedTime
+        if isReversed {
-        animate(delay: max(0, targetState.delay - elapsedTime))
+            if elapsedTime > targetState.delay + duration {
+                let backDelay = elapsedTime - (targetState.delay + duration)
+                return animate(delay: backDelay, duration: duration)
+            } else if elapsedTime > targetState.delay {
+                return animate(delay: 0, duration: duration - elapsedTime - targetState.delay)
+            }
+        } else {
+            if elapsedTime <= targetState.delay {
+                return animate(delay: targetState.delay - elapsedTime, duration: duration)
+            } else if elapsedTime <= targetState.delay + duration {
+                let timePassedDelay = elapsedTime - targetState.delay
+                return animate(delay: 0, duration: duration - timePassedDelay)
+            }
+        }
+        return 0
    }
    override func seek(to elapsedTime: TimeInterval) {
-        seek(layer: snapshot.layer, elapsedTime: elapsedTime)
+        let timeOffset = CGFloat(elapsedTime - targetState.delay)
-        if let v = contentLayer {
+        for (layer, key, anim) in animations {
-            seek(layer: v, elapsedTime: elapsedTime)
+            anim.speed = 0
-        }
+            anim.timeOffset = CFTimeInterval(timeOffset.clamp(0, CGFloat(anim.duration) - 0.001))
+            layer.removeAnimation(forKey: key)
-        if let v = overlayLayer {
+            layer.add(anim, forKey: key)
-            seek(layer: v, elapsedTime: elapsedTime)
        }
    }
-    override func startAnimations(isAppearing: Bool) {
+    override func startAnimations() -> TimeInterval {
        if let beginState = targetState.beginState?.state {
            let appeared = viewState(targetState: beginState)
            for (k, v) in appeared {
@@ -124,16 +147,16 @@ internal class MotionCoreAnimationViewContext: MotionAnimatorViewContext {
            transitionStates[k] = (fromValue, toValue)
        }
-        animate(delay: targetState.delay)
+        return animate(delay: targetState.delay, duration: duration)
    }
 }
-extension MotionCoreAnimationViewContext {
+fileprivate extension MotionCoreAnimationViewContext {
    /**
     Lazy loads the overlay layer.
     - Returns: A CALayer.
     */
-    fileprivate func getOverlayLayer() -> CALayer {
+    func getOverlayLayer() -> CALayer {
        if nil == overlayLayer {
            overlayLayer = CALayer()
            overlayLayer!.frame = snapshot.bounds
@@ -149,7 +172,7 @@ extension MotionCoreAnimationViewContext {
     - Parameter for key: A String.
     - Returns: An optional String.
     */
-    fileprivate func overlayKey(for key: String) -> String? {
+    func overlayKey(for key: String) -> String? {
        guard key.hasPrefix("overlay.") else {
            return nil
        }
@@ -164,9 +187,9 @@ extension MotionCoreAnimationViewContext {
     - Parameter for key: A String.
     - Returns: An optional Any value.
     */
-    fileprivate func currentValue(for key: String) -> Any? {
+    func currentValue(for key: String) -> Any? {
        if let key = overlayKey(for: key) {
-            return overlayLayer?.value(forKeyPath: key)
+            return (overlayLayer?.presentation() ?? overlayLayer)?.value(forKeyPath: key)
        }
        if false != snapshot.layer.animationKeys()?.isEmpty {
@@ -180,11 +203,12 @@ extension MotionCoreAnimationViewContext {
     Retrieves the animation for a given key.
     - Parameter key: String.
     - Parameter beginTime: A TimeInterval.
+     - Parameter duration: A TimeInterval.
     - Parameter fromValue: An optional Any value.
     - Parameter toValue: An optional Any value.
     - Parameter ignoreArc: A Boolean value to ignore an arc position.
     */
-    fileprivate func getAnimation(key: String, beginTime: TimeInterval, fromValue: Any?, toValue: Any?, ignoreArc: Bool = false) -> CAPropertyAnimation {
+    func getAnimation(key: String, beginTime: TimeInterval, duration: TimeInterval, fromValue: Any?, toValue: Any?, ignoreArc: Bool = false) -> CAPropertyAnimation {
        let key = overlayKey(for: key) ?? key
        let anim: CAPropertyAnimation
@@ -211,7 +235,7 @@ extension MotionCoreAnimationViewContext {
            let a = CASpringAnimation(keyPath: key)
            a.stiffness = stiffness
            a.damping = damping
-            a.duration = a.settlingDuration * 0.9
+            a.duration = a.settlingDuration
            a.fromValue = fromValue
            a.toValue = toValue
@@ -234,28 +258,118 @@ extension MotionCoreAnimationViewContext {
    }
    /**
+     Sets a new size for the given view.
+     - Parameter view: A UIView.
+     - Parameter newSize: A CGSize.
+     */
+    func setSize(view: UIView, newSize: CGSize) {
+        let oldSize = view.bounds.size
+        if .noSnapshot != targetState.snapshotType {
+            if 0 == oldSize.width || 0 == oldSize.height || 0 == newSize.width || 0 == newSize.height {
+                for v in view.subviews {
+                    v.center = newSize.center
+                    v.bounds.size = newSize
+                    setSize(view: v, newSize: newSize)
+                }
+            } else {
+                let sizeRatio = oldSize / newSize
+                for v in view.subviews {
+                    let center = v.center
+                    let size = v.bounds.size
+                    v.center = center / sizeRatio
+                    v.bounds.size = size / sizeRatio
+                    setSize(view: v, newSize: size / sizeRatio)
+                }
+            }
+            view.bounds.size = newSize
+        } else {
+            view.bounds.size = newSize
+            view.layoutSubviews()
+        }
+    }
+    /**
+     Executes a UIView based animation.
+     - Parameter duration: A TimeInterval.
+     - Parameter delay: A TimeInterval.
+     - Parameter _ animations: An animation block.
+     */
+    func uiViewBasedAnimate(duration: TimeInterval, delay: TimeInterval, _ animations: @escaping () -> Void) {
+        CALayer.motionAddedAnimations = []
+        if let (stiffness, damping) = targetState.spring {
+            UIView.animate(withDuration: duration, delay: delay, usingSpringWithDamping: 1, initialSpringVelocity: 0, options: [], animations: animations, completion: nil)
+            let addedAnimations = CALayer.motionAddedAnimations!
+            CALayer.motionAddedAnimations = nil
+            for (layer, key, anim) in addedAnimations {
+                if #available(iOS 9.0, *), let anim = anim as? CASpringAnimation {
+                    anim.stiffness = stiffness
+                    anim.damping = damping
+                    self.addAnimation(anim, for: key, to: layer)
+                } else {
+                    self.animations.append((layer, key, anim))
+                }
+            }
+        } else {
+            CATransaction.begin()
+            CATransaction.setAnimationTimingFunction(timingFunction)
+            UIView.animate(withDuration: duration, delay: delay, options: [], animations: animations, completion: nil)
+            CATransaction.commit()
+            let addedAnimations = CALayer.motionAddedAnimations!
+            CALayer.motionAddedAnimations = nil
+            self.animations.append(contentsOf: addedAnimations)
+        }
+    }
+    /**
+     Adds an animation to a given layer.
+     - Parameter _ animation: A CAAnimation.
+     - Parameter for key: A String.
+     - Parameter to layer: A CALayer.
+     */
+    func addAnimation(_ animation: CAAnimation, for key: String, to layer: CALayer) {
+        animations.append((layer, key, animation))
+        layer.add(animation, forKey: key)
+    }
+    /**
     Retrieves the duration of an animation, including the
     duration of the animation and the initial delay.
     - Parameter key: A String.
     - Parameter beginTime: A TimeInterval.
+     - Parameter duration: A TimeInterval.
     - Parameter fromValue: A optional Any value.
     - Parameter toValue: A optional Any value.
     - Returns: A TimeInterval.
     */
    @discardableResult
-    fileprivate func animate(key: String, beginTime: TimeInterval, fromValue: Any?, toValue: Any?) -> TimeInterval {
+    func animate(key: String, beginTime: TimeInterval, duration: TimeInterval, fromValue: Any?, toValue: Any?) -> TimeInterval {
-        let anim = getAnimation(key: key, beginTime:beginTime, fromValue: fromValue, toValue: toValue)
+        let anim = getAnimation(key: key, beginTime: beginTime, duration: duration, fromValue: fromValue, toValue: toValue)
        if let overlayKey = overlayKey(for: key) {
-            getOverlayLayer().add(anim, forKey: overlayKey)
+            addAnimation(anim, for: overlayKey, to: getOverlayLayer())
        } else {
            snapshot.layer.add(anim, forKey: key)
            switch key {
            case "cornerRadius", "contentsRect", "contentsScale":
-                contentLayer?.add(anim, forKey: key)
+                addAnimation(anim, for: key, to: snapshot.layer)
-                overlayLayer?.add(anim, forKey: key)
+                if let v = contentLayer {
+                    addAnimation(anim.copy() as! CAAnimation, for: key, to: v)
+                }
+                if let v = overlayLayer {
+                    addAnimation(anim.copy() as! CAAnimation, for: key, to: v)
+                }
            case "bounds.size":
                guard let fs = (fromValue as? NSValue)?.cgSizeValue else {
@@ -266,26 +380,17 @@ extension MotionCoreAnimationViewContext {
                    return 0
                }
-                // for the snapshotView(UIReplicantView): there is a
+                setSize(view: snapshot, newSize: fs)
-                // subview(UIReplicantContentView) that is hosting the real snapshot image.
+                uiViewBasedAnimate(duration: anim.duration, delay: beginTime - currentTime) { [weak self] in
-                // because we are using CAAnimations and not UIView animations,
+                    guard let `self` = self else {
-                // The snapshotView will not layout during animations.
+                        return
-                // we have to add two more animations to manually layout the content view.
+                    }
-                let fpn = NSValue(cgPoint: fs.center)
-                let tpn = NSValue(cgPoint: ts.center)
+                    self.setSize(view: self.snapshot, newSize: ts)
+                }
-                let a = getAnimation(key: "position", beginTime: 0, fromValue: fpn, toValue: tpn, ignoreArc: true)
-                a.beginTime = anim.beginTime
-                a.timingFunction = anim.timingFunction
-                a.duration = anim.duration
-                contentLayer?.add(a, forKey: "position")
-                contentLayer?.add(anim, forKey: key)
-                overlayLayer?.add(a, forKey: "position")
-                overlayLayer?.add(anim, forKey: key)
-            default: break
+            default:
+                addAnimation(anim, for: key, to: snapshot.layer)
            }
        }
@@ -295,26 +400,28 @@ extension MotionCoreAnimationViewContext {
    /**
     Animates the contentLayer and overlayLayer with a given delay.
     - Parameter delay: A TimeInterval.
+     - Parameter duration: A TimeInterval.
+     - Returns: A TimeInterval.
     */
-    fileprivate func animate(delay: TimeInterval) {
+    func animate(delay: TimeInterval, duration: TimeInterval) -> TimeInterval {
-        if let v = targetState.timingFunction {
+        for (layer, key, _) in animations {
-            timingFunction = v
+            layer.removeAnimation(forKey: key)
        }
-        if let v = targetState.duration {
+        if let tf = targetState.timingFunction {
-            duration = v
+            timingFunction = tf
        }
-        let beginTime = currentTime + delay
+        var timeUntilStop = duration
-        var finalDuration: TimeInterval = duration
+        animations = []
        for (key, (fromValue, toValue)) in transitionStates {
-            let neededTime = animate(key: key, beginTime: beginTime, fromValue: fromValue, toValue: toValue)
+            let neededTime = animate(key: key, beginTime: currentTime + delay, duration: duration, fromValue: fromValue, toValue: toValue)
-            finalDuration = max(finalDuration, neededTime + delay)
+            timeUntilStop = max(timeUntilStop, neededTime)
        }
-        duration = finalDuration
+        return timeUntilStop + delay
    }
    /**
@@ -322,7 +429,7 @@ extension MotionCoreAnimationViewContext {
     - Parameter targetState state: A MotionTransitionState.
     - Returns: A map of key paths to animation values.
     */
-    fileprivate func viewState(targetState ts: MotionTransitionState) -> [String: Any?] {
+    func viewState(targetState ts: MotionTransitionState) -> [String: Any?] {
        var ts = ts
        var values = [String: Any?]()
@@ -409,19 +516,4 @@ extension MotionCoreAnimationViewContext {
        return values
    }
-    /**
-     Moves a layer's animation to a given elapsed time.
-     - Parameter layer: A CALayer.
-     - Parameter elapsedTime: A TimeInterval.
-     */
-    fileprivate func seek(layer: CALayer, elapsedTime: TimeInterval) {
-        let timeOffset = elapsedTime - targetState.delay
-        for (key, anim) in layer.animations {
-            anim.speed = 0
-            anim.timeOffset = max(0, min(anim.duration - 0.01, timeOffset))
-            layer.removeAnimation(forKey: key)
-            layer.add(anim, forKey: key)
-        }
-    }
 }
--- a/Sources/Animator/BaseMotionAnimator.swift
+++ b/Sources/Animator/BaseMotionAnimator.swift
@@ -28,7 +28,7 @@
 import UIKit
-class BaseMotionAnimator: MotionAnimator {
+class MotionCoreAnimator: MotionAnimator {
    weak public var motion: Motion!
    /// A reference to the MotionContext.

--- a/Sources/Animator/MotionTransitionAnimator.swift
+++ b/Sources/Animator/MotionTransitionAnimator.swift
@@ -28,7 +28,7 @@
 import UIKit
-internal class MotionTransitionAnimator<T: MotionAnimatorViewContext>: BaseMotionAnimator, MotionHasInsertOrder {
+internal class MotionTransitionAnimator<T: MotionAnimatorViewContext>: MotionCoreAnimator, MotionHasInsertOrder {
    /// An index of views to their corresponding animator context.
    var viewToContexts = [UIView: T]()
@@ -114,8 +114,10 @@ internal class MotionTransitionAnimator<T: MotionAnimatorViewContext>: BaseMotio
        var duration: TimeInterval = 0
        for (_, v) in viewToContexts {
-            v.resume(at: elapsedTime, isReversed: isReversed)
+            if v.targetState.duration == nil {
-            duration = max(duration, v.duration)
+                v.duration = max(v.duration, v.snapshot.optimizedDuration(targetState: v.targetState) + elapsedTime)
+            }
+            duration = max(duration, v.resume(at: elapsedTime, isReversed: isReversed))
        }
        return duration
@@ -144,11 +146,11 @@ extension MotionTransitionAnimator {
     */
    fileprivate func animate(view: UIView, isAppearing: Bool) {
        let s = context.snapshotView(for: view)
-        let v = T(animator: self, snapshot: s, targetState: context[view]!)
+        let v = T(animator: self, snapshot: s, targetState: context[view]!, isAppearing: isAppearing)
        viewToContexts[view] = v
-        v.startAnimations(isAppearing: isAppearing)
+        v.startAnimations()
    }
 }
--- a/Sources/Extensions/Motion+CALayer.swift
+++ b/Sources/Extensions/Motion+CALayer.swift
@@ -29,6 +29,26 @@ import UIKit
 extension CALayer: CAAnimationDelegate {}
 internal extension CALayer {
+    internal static var motionAddedAnimations: [(CALayer, String, CAAnimation)]? = {
+        let swizzling: (AnyClass, Selector, Selector) -> Void = { forClass, originalSelector, swizzledSelector in
+            if let originalMethod = class_getInstanceMethod(forClass, originalSelector), let swizzledMethod = class_getInstanceMethod(forClass, swizzledSelector) {
+                method_exchangeImplementations(originalMethod, swizzledMethod)
+            }
+        }
+        swizzling(CALayer.self, #selector(add(_:forKey:)), #selector(motionAdd(anim:forKey:)))
+        return nil
+    }()
+    @objc
+    dynamic func motionAdd(anim: CAAnimation, forKey: String?) {
+        let copiedAnim = anim.copy() as! CAAnimation
+        copiedAnim.delegate = nil // having delegate resulted some weird animation behavior
+        CALayer.motionAddedAnimations?.append((self, forKey!, copiedAnim))
+        motionAdd(anim: anim, forKey: forKey)
+    }
    /// Retrieves all currently running animations for the layer.
    var animations: [(String, CAAnimation)] {
        guard let keys = animationKeys() else {

--- a/Sources/Extensions/Motion+CG.swift
+++ b/Sources/Extensions/Motion+CG.swift
@@ -187,6 +187,16 @@ public func /(left: CGPoint, right: CGPoint) -> CGPoint {
 /**
 A handler for the (/) operator.
+ - Parameter left: A CGPoint.
+ - Parameter right: A CGSize.
+ - Returns: A CGPoint.
+ */
+public func /(left: CGPoint, right: CGSize) -> CGPoint {
+    return CGPoint(x: left.x / right.width, y: left.y / right.height)
+}
+/**
+ A handler for the (/) operator.
 - Parameter left: A CGSize.
 - Parameter right: A CGSize.
 - Returns: A CGSize.

--- a/Sources/Extensions/Motion+UIView.swift
+++ b/Sources/Extensions/Motion+UIView.swift
@@ -284,6 +284,17 @@ internal extension UIView {
    }
    /**
+     Calculates the optimized duration for a view.
+     - Parameter targetState: A MotionTransitionState.
+     - Returns: A TimeInterval.
+     */
+    func optimizedDuration(targetState: MotionTransitionState) -> TimeInterval {
+        return optimizedDuration(position: targetState.position,
+                                     size: targetState.size,
+                                transform: targetState.transform)
+    }
+    /**
     Takes a snapshot of a view usinag the UI graphics context.
     - Returns: A UIView with an embedded UIImageView.
     */