rework of Motion+CG

Sources/Extensions/Motion+CG.swift

 /*
- * Copyright (C) 2015 - 2017, Daniel Dahan and CosmicMind, Inc. <http://cosmicmind.com>.
- * All rights reserved.
+ * The MIT License (MIT)
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
+ * Copyright (C) 2017, Daniel Dahan and CosmicMind, Inc. <http://cosmicmind.com>.
+ * All rights reserved.
  *
- *	*	Redistributions of source code must retain the above copyright notice, this
- *		list of conditions and the following disclaimer.
+ * Original Inspiration & Author
+ * Copyright (c) 2016 Luke Zhao <me@lkzhao.com>
  *
- *	*	Redistributions in binary form must reproduce the above copyright notice,
- *		this list of conditions and the following disclaimer in the documentation
- *		and/or other materials provided with the distribution.
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
  *
- *	*	Neither the name of CosmicMind nor the names of its
- *		contributors may be used to endorse or promote products derived from
- *		this software without specific prior written permission.
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
  *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
  */
 
 import MetalKit
 
-internal struct KeySet<Key: Hashable, Value: Hashable> {
-    /// A reference to the dictionary storing the key / Set pairs.
-    fileprivate var dictionary = [Key: Set<Value>]()
-    
-    /**
-     Subscript for matching keys and returning the corresponding set.
-     - Parameter key: A Key type.
-     - Returns: A Set<Value> type.
-     */
-    subscript(key: Key) -> Set<Value> {
-        mutating get {
-            if nil == dictionary[key] {
-                dictionary[key] = Set<Value>()
+extension CGSize {
+    /// THe center point based on width and height.
+    var center: CGPoint {
+        return CGPoint(x: width / 2, y: height / 2)
     }
     
-            return dictionary[key]!
-        }
-        set(value) {
-            dictionary[key] = value
+    /// Top left point based on the size.
+    var topLeft: CGPoint {
+        return .zero
     }
+    
+    /// Top right point based on the size.
+    var topRight: CGPoint {
+        return CGPoint(x: width, y: 0)
     }
-}
     
-internal extension CGSize {
-    internal var center: CGPoint {
-        return CGPoint(x: width / 2, y: height / 2)
+    /// Bottom left point based on the size.
+    var bottomLeftPoint: CGPoint {
+        return CGPoint(x: 0, y: height)
     }
     
-    internal var point: CGPoint {
+    /// Bottom right point based on the size.
+    var bottomRight: CGPoint {
         return CGPoint(x: width, y: height)
     }
     
-    internal func transform(_ t: CGAffineTransform) -> CGSize {
+    /**
+     Retrieves the size based on a given CGAffineTransform.
+     - Parameter _ t: A CGAffineTransform.
+     - Returns: A CGSize.
+     */
+    func transform(_ t: CGAffineTransform) -> CGSize {
         return applying(t)
     }
     
-    internal func transform(_ t: CATransform3D) -> CGSize {
+    /**
+     Retrieves the size based on a given CATransform3D.
+     - Parameter _ t: A CGAffineTransform.
+     - Returns: A CGSize.
+     */
+    func transform(_ t: CATransform3D) -> CGSize {
         return applying(CATransform3DGetAffineTransform(t))
     }
 }
 
-internal extension CGRect {
+extension CGRect {
+    /// A center point based on the origin and size values.
     var center: CGPoint {
         return CGPoint(x: origin.x + size.width / 2, y: origin.y + size.height / 2)
     }
     
+    /// The bounding box size based from from the frame's rect.
     var bounds: CGRect {
-        return CGRect(origin: CGPoint.zero, size: size)
+        return CGRect(origin: .zero, size: size)
     }
     
+    /**
+     An initializer with a given point and size.
+     - Parameter center: A CGPoint.
+     - Parameter size: A CGSize.
+     */
     init(center: CGPoint, size: CGSize) {
         self.init(x: center.x - size.width / 2, y: center.y - size.height / 2, width: size.width, height: size.height)
     }
 }
 
-internal extension CGFloat {
+extension CGFloat {
+    /**
+     Calculates the limiting position to an area.
+     - Parameter _ a: A CGFloat.
+     - Parameter _ b: A CGFloat.
+     - Returns: A CGFloat.
+     */
     func clamp(_ a: CGFloat, _ b: CGFloat) -> CGFloat {
         return self < a ? a : self > b ? b : self
     }
 }
 
-internal extension CGPoint {
+extension CGPoint {
+    /**
+     Calculates a translation point based on the origin value.
+     - Parameter _ dx: A CGFloat.
+     - Parameter _ dy: A CGFloat.
+     - Returns: A CGPoint.
+     */
     func translate(_ dx: CGFloat, dy: CGFloat) -> CGPoint {
         return CGPoint(x: x + dx, y: y + dy)
     }
     
+    /**
+     Calculates a transform point based on a given CGAffineTransform.
+     - Parameter _ t: CGAffineTransform.
+     - Returns: A CGPoint.
+     */
     func transform(_ t: CGAffineTransform) -> CGPoint {
         return applying(t)
     }
     
+    /**
+     Calculates a transform point based on a given CATransform3D.
+     - Parameter _ t: CATransform3D.
+     - Returns: A CGPoint.
+     */
     func transform(_ t: CATransform3D) -> CGPoint {
         return applying(CATransform3DGetAffineTransform(t))
     }
     
+    /**
+     Calculates the distance between the CGPoint and given CGPoint.
+     - Parameter _ b: A CGPoint.
+     - Returns: A CGFloat.
+     */
     func distance(_ b: CGPoint) -> CGFloat {
         return sqrt(pow(x - b.x, 2) + pow(y - b.y, 2))
     }
 }
 
-internal func +(left: CGPoint, right: CGPoint) -> CGPoint {
+/**
+ A handler for the (+) operator.
+ - Parameter left: A CGPoint.
+ - Parameter right: A CGPoint.
+ - Returns: A CGPoint.
+ */
+func +(left: CGPoint, right: CGPoint) -> CGPoint {
     return CGPoint(x: left.x + right.x, y: left.y + right.y)
 }
 
-internal func -(left: CGPoint, right: CGPoint) -> CGPoint {
+/**
+ A handler for the (-) operator.
+ - Parameter left: A CGPoint.
+ - Parameter right: A CGPoint.
+ - Returns: A CGPoint.
+ */
+func -(left: CGPoint, right: CGPoint) -> CGPoint {
     return CGPoint(x: left.x - right.x, y: left.y - right.y)
 }
 
-internal func /(left: CGPoint, right: CGFloat) -> CGPoint {
+/**
+ A handler for the (/) operator.
+ - Parameter left: A CGPoint.
+ - Parameter right: A CGFloat.
+ - Returns: A CGPoint.
+ */
+func /(left: CGPoint, right: CGFloat) -> CGPoint {
     return CGPoint(x: left.x / right, y: left.y / right)
 }
 
-internal func /(left: CGPoint, right: CGPoint) -> CGPoint {
+/**
+ A handler for the (/) operator.
+ - Parameter left: A CGPoint.
+ - Parameter right: A CGPoint.
+ - Returns: A CGPoint.
+ */
+func /(left: CGPoint, right: CGPoint) -> CGPoint {
     return CGPoint(x: left.x / right.x, y: left.y / right.y)
 }
 
-internal func *(left: CGPoint, right: CGFloat) -> CGPoint {
+/**
+ A handler for the (/) operator.
+ - Parameter left: A CGSize.
+ - Parameter right: A CGSize.
+ - Returns: A CGSize.
+ */
+func /(left: CGSize, right: CGSize) -> CGSize {
+    return CGSize(width: left.width / right.width, height: left.height / right.height)
+}
+
+/**
+ A handler for the (*) operator.
+ - Parameter left: A CGPoint.
+ - Parameter right: A CGFloat.
+ - Returns: A CGPoint.
+ */
+func *(left: CGPoint, right: CGFloat) -> CGPoint {
     return CGPoint(x: left.x * right, y: left.y * right)
 }
 
-internal func *(left: CGPoint, right: CGSize) -> CGPoint {
+/**
+ A handler for the (*) operator.
+ - Parameter left: A CGPoint.
+ - Parameter right: A CGSize.
+ - Returns: A CGPoint.
+ */
+func *(left: CGPoint, right: CGSize) -> CGPoint {
     return CGPoint(x: left.x * right.width, y: left.y * right.width)
 }
 
-internal func *(left: CGFloat, right: CGPoint) -> CGPoint {
+/**
+ A handler for the (*) operator.
+ - Parameter left: A CGFloat.
+ - Parameter right: A CGPoint.
+ - Returns: A CGPoint.
+ */
+func *(left: CGFloat, right: CGPoint) -> CGPoint {
     return right * left
 }
 
-internal func *(left: CGPoint, right: CGPoint) -> CGPoint {
+/**
+ A handler for the (*) operator.
+ - Parameter left: A CGPoint.
+ - Parameter right: A CGPoint.
+ - Returns: A CGPoint.
+ */
+func *(left: CGPoint, right: CGPoint) -> CGPoint {
     return CGPoint(x: left.x * right.x, y: left.y * right.y)
 }
 
-internal prefix func -(point: CGPoint) -> CGPoint {
-    return CGPoint.zero - point
-}
-
-internal func abs(_ p: CGPoint) -> CGPoint {
-    return CGPoint(x: abs(p.x), y: abs(p.y))
-}
-
-internal func *(left: CGSize, right: CGFloat) -> CGSize {
+/**
+ A handler for the (*) prefix.
+ - Parameter left: A CGSize.
+ - Parameter right: A CGFloat.
+ - Returns: A CGSize.
+ */
+func *(left: CGSize, right: CGFloat) -> CGSize {
     return CGSize(width: left.width * right, height: left.height * right)
 }
 
-internal func *(left: CGSize, right: CGSize) -> CGSize {
+/**
+ A handler for the (*) prefix.
+ - Parameter left: A CGSize.
+ - Parameter right: A CGSize.
+ - Returns: A CGSize.
+ */
+func *(left: CGSize, right: CGSize) -> CGSize {
     return CGSize(width: left.width * right.width, height: left.height * right.width)
 }
 
-internal func /(left: CGSize, right: CGSize) -> CGSize {
-    return CGSize(width: left.width / right.width, height: left.height / right.height)
-}
-
-internal func == (lhs: CATransform3D, rhs: CATransform3D) -> Bool {
+/**
+ A handler for the (==) operator.
+ - Parameter lhs: A CATransform3D.
+ - Parameter rhs: A CATransform3D.
+ - Returns: A Bool.
+ */
+func ==(lhs: CATransform3D, rhs: CATransform3D) -> Bool {
     var lhs = lhs
     var rhs = rhs
     return memcmp(&lhs, &rhs, MemoryLayout<CATransform3D>.size) == 0
 }
 
-internal func != (lhs: CATransform3D, rhs: CATransform3D) -> Bool {
+/**
+ A handler for the (!=) operator.
+ - Parameter lhs: A CATransform3D.
+ - Parameter rhs: A CATransform3D.
+ - Returns: A Bool.
+ */
+func !=(lhs: CATransform3D, rhs: CATransform3D) -> Bool {
     return !(lhs == rhs)
 }
+
+/**
+ A handler for the (-) prefix.
+ - Parameter point: A CGPoint.
+ - Returns: A CGPoint.
+ */
+prefix func -(point: CGPoint) -> CGPoint {
+    return CGPoint.zero - point
+}
+
+/**
+ A handler for the (abs) function.
+ - Parameter _ p: A CGPoint.
+ - Returns: A CGPoint.
+ */
+func abs(_ p: CGPoint) -> CGPoint {
+    return CGPoint(x: abs(p.x), y: abs(p.y))
+}

Sources/Extensions/Motion+UIView.swift

@@ -30,24 +30,22 @@ import UIKit
 
 internal extension UIView {
     func optimizedDuration(fromPosition: CGPoint, toPosition: CGPoint?, size: CGSize?, transform: CATransform3D?) -> TimeInterval {
-        let fromPos = fromPosition
-        let toPos = toPosition ?? fromPos
+        let toPos = toPosition ?? fromPosition
         let fromSize = (layer.presentation() ?? layer).bounds.size
         let toSize = size ?? fromSize
         let fromTransform = (layer.presentation() ?? layer).transform
         let toTransform = transform ?? fromTransform
         
-        let realFromPos = CGPoint.zero.transform(fromTransform) + fromPos
+        let realFromPos = CGPoint.zero.transform(fromTransform) + fromPosition
         let realToPos = CGPoint.zero.transform(toTransform) + toPos
         
         let realFromSize = fromSize.transform(fromTransform)
         let realToSize = toSize.transform(toTransform)
         
-        let movePoints = (realFromPos.distance(realToPos) + realFromSize.point.distance(realToSize.point))
+        let movePoints = realFromPos.distance(realToPos) + realFromSize.bottomRight.distance(realToSize.bottomRight)
         
         // duration is 0.2 @ 0 to 0.375 @ 500
-        let duration = 0.208 + Double(movePoints.clamp(0, 500)) / 3000
-        return duration
+        return 0.208 + Double(movePoints.clamp(0, 500)) / 3000
     }
 }