diff --git a/FSPageViewExample-Swift/FSPagerViewExample/PageControlExampleViewController.swift b/FSPageViewExample-Swift/FSPagerViewExample/PageControlExampleViewController.swift
index 7e00edd..669a203 100644
--- a/FSPageViewExample-Swift/FSPagerViewExample/PageControlExampleViewController.swift
+++ b/FSPageViewExample-Swift/FSPagerViewExample/PageControlExampleViewController.swift
@@ -98,14 +98,14 @@ class PageControlExampleViewController: UIViewController,UITableViewDataSource,U
         heartPath.addArc(
             withCenter: CGPoint(x: width*0.25,y: height*0.25),
             radius: width * 0.25,
-            startAngle: CGFloat(M_PI),
+            startAngle: .pi,
             endAngle: 0,
             clockwise: true
         )
         heartPath.addArc(
             withCenter: CGPoint(x: width*0.75, y: height*0.25),
             radius: width * 0.25,
-            startAngle: CGFloat(M_PI),
+            startAngle: .pi,
             endAngle: 0,
             clockwise: true
         )
diff --git a/FSPageViewExample-Swift/FSPagerViewExample/TransformerExampleViewController.swift b/FSPageViewExample-Swift/FSPagerViewExample/TransformerExampleViewController.swift
index d54fe4c..4acc36d 100644
--- a/FSPageViewExample-Swift/FSPagerViewExample/TransformerExampleViewController.swift
+++ b/FSPageViewExample-Swift/FSPagerViewExample/TransformerExampleViewController.swift
@@ -26,7 +26,7 @@ class TransformerExampleViewController: UIViewController,FSPagerViewDataSource,F
             let type = self.transformerTypes[typeIndex]
             self.pagerView.transformer = FSPagerViewTransformer(type:type)
             switch type {
-            case .none, .crossFading, .zoomOut, .depth:
+            case .crossFading, .zoomOut, .depth:
                 self.pagerView.itemSize = .zero // 'Zero' means fill the size of parent
             case .linear, .overlap:
                 let transform = CGAffineTransform(scaleX: 0.6, y: 0.75)
diff --git a/FSPagerView/FSPagerView.xcodeproj/xcshareddata/xcschemes/FSPagerView.xcscheme b/FSPagerView/FSPagerView.xcodeproj/xcshareddata/xcschemes/FSPagerView.xcscheme
index 94303f0..bbf9d9a 100644
--- a/FSPagerView/FSPagerView.xcodeproj/xcshareddata/xcschemes/FSPagerView.xcscheme
+++ b/FSPagerView/FSPagerView.xcodeproj/xcshareddata/xcschemes/FSPagerView.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0820"
+   LastUpgradeVersion = "0830"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/FSPagerViewExample-Objc/FSPagerViewExample-Objc.xcodeproj/project.pbxproj b/FSPagerViewExample-Objc/FSPagerViewExample-Objc.xcodeproj/project.pbxproj
index 2f1ed94..4cebee3 100644
--- a/FSPagerViewExample-Objc/FSPagerViewExample-Objc.xcodeproj/project.pbxproj
+++ b/FSPagerViewExample-Objc/FSPagerViewExample-Objc.xcodeproj/project.pbxproj
@@ -251,7 +251,7 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 0820;
-				LastUpgradeCheck = 0820;
+				LastUpgradeCheck = 0830;
 				ORGANIZATIONNAME = "Wenchao Ding";
 				TargetAttributes = {
 					F9C694481E40C6C1007084B6 = {
@@ -490,6 +490,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
+				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VALIDATE_PRODUCT = YES;
 			};
diff --git a/FSPagerViewExample-Objc/FSPagerViewExample-Objc.xcodeproj/xcuserdata/wenchaoding.xcuserdatad/xcschemes/FSPagerViewExample-Objc.xcscheme b/FSPagerViewExample-Objc/FSPagerViewExample-Objc.xcodeproj/xcuserdata/wenchaoding.xcuserdatad/xcschemes/FSPagerViewExample-Objc.xcscheme
index 4d1124e..0d5c164 100644
--- a/FSPagerViewExample-Objc/FSPagerViewExample-Objc.xcodeproj/xcuserdata/wenchaoding.xcuserdatad/xcschemes/FSPagerViewExample-Objc.xcscheme
+++ b/FSPagerViewExample-Objc/FSPagerViewExample-Objc.xcodeproj/xcuserdata/wenchaoding.xcuserdatad/xcschemes/FSPagerViewExample-Objc.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0820"
+   LastUpgradeVersion = "0830"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/FSPagerViewExample-Objc/FSPagerViewExample-Objc/PageControlExampleViewController.m b/FSPagerViewExample-Objc/FSPagerViewExample-Objc/PageControlExampleViewController.m
index 72f5e0d..e6e7df4 100644
--- a/FSPagerViewExample-Objc/FSPagerViewExample-Objc/PageControlExampleViewController.m
+++ b/FSPagerViewExample-Objc/FSPagerViewExample-Objc/PageControlExampleViewController.m
@@ -179,7 +179,7 @@
             }
             break;
         }
-        case 3: {
+        case 2: {
             self.pageControl.interitemSpacing = 6.0 + sender.value*10.0; // [6 - 16]
             break;
         }
diff --git a/FSPagerViewExample-Objc/FSPagerViewExample-Objc/TransformerExampleViewController.m b/FSPagerViewExample-Objc/FSPagerViewExample-Objc/TransformerExampleViewController.m
index 7796178..a9ffddf 100644
--- a/FSPagerViewExample-Objc/FSPagerViewExample-Objc/TransformerExampleViewController.m
+++ b/FSPagerViewExample-Objc/FSPagerViewExample-Objc/TransformerExampleViewController.m
@@ -140,6 +140,7 @@
             break;
         }
         default:
+            type = FSPagerViewTransformerTypeZoomOut;
             break;
     }
     self.pagerView.transformer = [[FSPagerViewTransformer alloc] initWithType:type];
diff --git a/Sources/FSPageViewTransformer.swift b/Sources/FSPageViewTransformer.swift
index 946d7fe..8a77c86 100644
--- a/Sources/FSPageViewTransformer.swift
+++ b/Sources/FSPageViewTransformer.swift
@@ -10,7 +10,6 @@ import UIKit
 
 @objc
 public enum FSPagerViewTransformerType: Int {
-    case none
     case crossFading
     case zoomOut
     case depth
@@ -25,13 +24,12 @@ public enum FSPagerViewTransformerType: Int {
 open class FSPagerViewTransformer: NSObject {
     
     open internal(set) weak var pagerView: FSPagerView?
-    open internal(set) var type: FSPagerViewTransformerType = .none
+    open internal(set) var type: FSPagerViewTransformerType
     
     open var minimumScale: CGFloat = 0.65
     open var minimumAlpha: CGFloat = 0.6
     
     public init(type: FSPagerViewTransformerType) {
-        super.init()
         self.type = type
         switch type {
         case .zoomOut:
@@ -43,10 +41,6 @@ open class FSPagerViewTransformer: NSObject {
         }
     }
     
-    public override init () {
-        super.init()
-    }
-    
     // Apply transform to attributes - zIndex: Int, frame: CGRect, alpha: CGFloat, transform: CGAffineTransform or transform3D: CATransform3D.
     open func applyTransform(to attributes: FSPagerViewLayoutAttributes) {
         guard let pagerView = self.pagerView else {
@@ -56,8 +50,6 @@ open class FSPagerViewTransformer: NSObject {
         let scrollDirection = pagerView.scrollDirection
         let itemSpacing = (scrollDirection == .horizontal ? attributes.bounds.width : attributes.bounds.height) + self.proposedInteritemSpacing()
         switch self.type {
-        case .none:
-            break
         case .crossFading:
             var zIndex = 0
             var alpha: CGFloat = 0
@@ -172,7 +164,7 @@ open class FSPagerViewTransformer: NSObject {
                 return
             }
             let position = min(max(-position,-1) ,1)
-            let rotation = sin(position*CGFloat(M_PI_2)) * CGFloat(M_PI_4)*1.5
+            let rotation = sin(position*(.pi)*0.5)*(.pi)*0.25*1.5
             let translationZ = -itemSpacing * 0.5 * abs(position)
             var transform3D = CATransform3DIdentity
             transform3D.m34 = -0.002
@@ -192,7 +184,7 @@ open class FSPagerViewTransformer: NSObject {
             case -5 ... 5:
                 let itemSpacing = attributes.bounds.width+self.proposedInteritemSpacing()
                 let count: CGFloat = 14
-                let circle: CGFloat = CGFloat(M_PI) * 2.0
+                let circle: CGFloat = .pi * 2.0
                 let radius = itemSpacing * count / circle
                 let ty = radius * (self.type == .ferrisWheel ? 1 : -1)
                 let theta = circle / count
@@ -215,7 +207,7 @@ open class FSPagerViewTransformer: NSObject {
                 attributes.alpha = 1
                 attributes.zIndex = Int((1-position) * CGFloat(10))
                 let direction: CGFloat = position < 0 ? 1 : -1
-                let theta = position * CGFloat(M_PI_2) * (scrollDirection == .horizontal ? 1 : -1)
+                let theta = position * .pi * 0.5 * (scrollDirection == .horizontal ? 1 : -1)
                 let radius = scrollDirection == .horizontal ? attributes.bounds.width : attributes.bounds.height
                 var transform3D = CATransform3DIdentity
                 transform3D.m34 = -0.002
@@ -262,7 +254,7 @@ open class FSPagerViewTransformer: NSObject {
             guard scrollDirection == .horizontal else {
                 return 0
             }
-            return -pagerView.itemSize.width * sin(CGFloat(M_PI_4)/4.0*3.0)
+            return -pagerView.itemSize.width * sin(.pi*0.25*0.25*3.0)
         case .ferrisWheel,.invertedFerrisWheel:
             guard scrollDirection == .horizontal else {
                 return 0