diff --git a/Source/Charts/Animation/Animator.swift b/Source/Charts/Animation/Animator.swift
index cec0987572..042012b1ba 100644
--- a/Source/Charts/Animation/Animator.swift
+++ b/Source/Charts/Animation/Animator.swift
@@ -39,23 +39,23 @@ open class Animator: NSObject
     /// the phase that is animated and influences the drawn values on the y-axis
     @objc open var phaseY: Double = 1.0
     
-    fileprivate var _startTimeX: TimeInterval = 0.0
-    fileprivate var _startTimeY: TimeInterval = 0.0
-    fileprivate var _displayLink: NSUIDisplayLink?
+    private var _startTimeX: TimeInterval = 0.0
+    private var _startTimeY: TimeInterval = 0.0
+    private var _displayLink: NSUIDisplayLink?
     
-    fileprivate var _durationX: TimeInterval = 0.0
-    fileprivate var _durationY: TimeInterval = 0.0
+    private var _durationX: TimeInterval = 0.0
+    private var _durationY: TimeInterval = 0.0
     
-    fileprivate var _endTimeX: TimeInterval = 0.0
-    fileprivate var _endTimeY: TimeInterval = 0.0
-    fileprivate var _endTime: TimeInterval = 0.0
+    private var _endTimeX: TimeInterval = 0.0
+    private var _endTimeY: TimeInterval = 0.0
+    private var _endTime: TimeInterval = 0.0
     
-    fileprivate var _enabledX: Bool = false
-    fileprivate var _enabledY: Bool = false
-    
-    fileprivate var _easingX: ChartEasingFunctionBlock?
-    fileprivate var _easingY: ChartEasingFunctionBlock?
+    private var _enabledX: Bool = false
+    private var _enabledY: Bool = false
     
+    private var _easingX: ChartEasingFunctionBlock?
+    private var _easingY: ChartEasingFunctionBlock?
+
     public override init()
     {
         super.init()
@@ -68,11 +68,10 @@ open class Animator: NSObject
     
     @objc open func stop()
     {
-        guard let _displayLink = _displayLink else {
-            return
-        }
-        _displayLink.remove(from: RunLoop.main, forMode: RunLoopMode.commonModes)
-        self._displayLink = nil
+        guard _displayLink != nil else { return }
+
+        _displayLink?.remove(from: .main, forMode: .commonModes)
+        _displayLink = nil
 
         _enabledX = false
         _enabledY = false
@@ -91,7 +90,7 @@ open class Animator: NSObject
         stopBlock?()
     }
     
-    fileprivate func updateAnimationPhases(_ currentTime: TimeInterval)
+    private func updateAnimationPhases(_ currentTime: TimeInterval)
     {
         if _enabledX
         {
@@ -103,7 +102,7 @@ open class Animator: NSObject
                 elapsed = duration
             }
            
-            phaseX = _easingX?(elapsed, duration) ?? Double(elapsed / duration)
+            phaseX = _easingX?(elapsed, duration) ?? elapsed / duration
         }
         
         if _enabledY
@@ -115,26 +114,18 @@ open class Animator: NSObject
             {
                 elapsed = duration
             }
-            
-            if let _easingY = _easingY
-            {
-                phaseY = _easingY(elapsed, duration)
-            }
-            else
-            {
-                phaseY = Double(elapsed / duration)
-            }
+
+            phaseY = _easingY?(elapsed, duration) ?? elapsed / duration
         }
     }
     
-    @objc fileprivate func animationLoop()
+    @objc private func animationLoop()
     {
         let currentTime: TimeInterval = CACurrentMediaTime()
         
         updateAnimationPhases(currentTime)
 
         delegate?.animatorUpdated(self)
-
         updateBlock?()
         
         if currentTime >= _endTime
@@ -202,20 +193,11 @@ open class Animator: NSObject
     /// - parameter xAxisDuration: duration for animating the x axis
     /// - parameter yAxisDuration: duration for animating the y axis
     /// - parameter easingOption: the easing function for the animation
-    @objc open func animate(xAxisDuration: TimeInterval, yAxisDuration: TimeInterval, easingOption: ChartEasingOption)
+    @objc open func animate(xAxisDuration: TimeInterval, yAxisDuration: TimeInterval, easingOption: ChartEasingOption = .easeInOutSine)
     {
         animate(xAxisDuration: xAxisDuration, yAxisDuration: yAxisDuration, easing: easingFunctionFromOption(easingOption))
     }
-    
-    /// Animates the drawing / rendering of the chart on both x- and y-axis with the specified animation time.
-    /// If `animate(...)` is called, no further calling of `invalidate()` is necessary to refresh the chart.
-    /// - parameter xAxisDuration: duration for animating the x axis
-    /// - parameter yAxisDuration: duration for animating the y axis
-    @objc open func animate(xAxisDuration: TimeInterval, yAxisDuration: TimeInterval)
-    {
-        animate(xAxisDuration: xAxisDuration, yAxisDuration: yAxisDuration, easingOption: .easeInOutSine)
-    }
-    
+
     /// Animates the drawing / rendering of the chart the x-axis with the specified animation time.
     /// If `animate(...)` is called, no further calling of `invalidate()` is necessary to refresh the chart.
     /// - parameter xAxisDuration: duration for animating the x axis
@@ -233,13 +215,11 @@ open class Animator: NSObject
         // Take care of the first frame if rendering is already scheduled...
         updateAnimationPhases(_startTimeX)
         
-        if _enabledX || _enabledY
+        if _enabledX || _enabledY,
+            _displayLink == nil
         {
-            if _displayLink == nil
-            {
-                _displayLink = NSUIDisplayLink(target: self, selector: #selector(animationLoop))
-                _displayLink?.add(to: RunLoop.main, forMode: RunLoopMode.commonModes)
-            }
+            _displayLink = NSUIDisplayLink(target: self, selector: #selector(animationLoop))
+            _displayLink?.add(to: .main, forMode: .commonModes)
         }
     }
     
@@ -247,19 +227,11 @@ open class Animator: NSObject
     /// If `animate(...)` is called, no further calling of `invalidate()` is necessary to refresh the chart.
     /// - parameter xAxisDuration: duration for animating the x axis
     /// - parameter easingOption: the easing function for the animation
-    @objc open func animate(xAxisDuration: TimeInterval, easingOption: ChartEasingOption)
+    @objc open func animate(xAxisDuration: TimeInterval, easingOption: ChartEasingOption = .easeInOutSine)
     {
         animate(xAxisDuration: xAxisDuration, easing: easingFunctionFromOption(easingOption))
     }
-    
-    /// Animates the drawing / rendering of the chart the x-axis with the specified animation time.
-    /// If `animate(...)` is called, no further calling of `invalidate()` is necessary to refresh the chart.
-    /// - parameter xAxisDuration: duration for animating the x axis
-    @objc open func animate(xAxisDuration: TimeInterval)
-    {
-        animate(xAxisDuration: xAxisDuration, easingOption: .easeInOutSine)
-    }
-    
+
     /// Animates the drawing / rendering of the chart the y-axis with the specified animation time.
     /// If `animate(...)` is called, no further calling of `invalidate()` is necessary to refresh the chart.
     /// - parameter yAxisDuration: duration for animating the y axis
@@ -277,13 +249,11 @@ open class Animator: NSObject
         // Take care of the first frame if rendering is already scheduled...
         updateAnimationPhases(_startTimeY)
         
-        if _enabledX || _enabledY
+        if _enabledX || _enabledY,
+            _displayLink == nil
         {
-            if _displayLink == nil
-            {
-                _displayLink = NSUIDisplayLink(target: self, selector: #selector(animationLoop))
-                _displayLink?.add(to: RunLoop.main, forMode: RunLoopMode.commonModes)
-            }
+            _displayLink = NSUIDisplayLink(target: self, selector: #selector(animationLoop))
+            _displayLink?.add(to: .main, forMode: .commonModes)
         }
     }
     
@@ -291,16 +261,8 @@ open class Animator: NSObject
     /// If `animate(...)` is called, no further calling of `invalidate()` is necessary to refresh the chart.
     /// - parameter yAxisDuration: duration for animating the y axis
     /// - parameter easingOption: the easing function for the animation
-    @objc open func animate(yAxisDuration: TimeInterval, easingOption: ChartEasingOption)
+    @objc open func animate(yAxisDuration: TimeInterval, easingOption: ChartEasingOption = .easeInOutSine)
     {
         animate(yAxisDuration: yAxisDuration, easing: easingFunctionFromOption(easingOption))
     }
-    
-    /// Animates the drawing / rendering of the chart the y-axis with the specified animation time.
-    /// If `animate(...)` is called, no further calling of `invalidate()` is necessary to refresh the chart.
-    /// - parameter yAxisDuration: duration for animating the y axis
-    @objc open func animate(yAxisDuration: TimeInterval)
-    {
-        animate(yAxisDuration: yAxisDuration, easingOption: .easeInOutSine)
-    }
 }
diff --git a/Source/Charts/Charts/BarChartView.swift b/Source/Charts/Charts/BarChartView.swift
index 685cac6150..16d7ed1674 100644
--- a/Source/Charts/Charts/BarChartView.swift
+++ b/Source/Charts/Charts/BarChartView.swift
@@ -16,10 +16,10 @@ import CoreGraphics
 open class BarChartView: BarLineChartViewBase, BarChartDataProvider
 {
     /// if set to true, all values are drawn above their bars, instead of below their top
-    fileprivate var _drawValueAboveBarEnabled = true
+    private var _drawValueAboveBarEnabled = true
 
     /// if set to true, a grey area is drawn behind each bar that indicates the maximum value
-    fileprivate var _drawBarShadowEnabled = false
+    private var _drawBarShadowEnabled = false
     
     internal override func initialize()
     {
diff --git a/Source/Charts/Charts/BarLineChartViewBase.swift b/Source/Charts/Charts/BarLineChartViewBase.swift
index 135b707728..1f07a19084 100644
--- a/Source/Charts/Charts/BarLineChartViewBase.swift
+++ b/Source/Charts/Charts/BarLineChartViewBase.swift
@@ -21,18 +21,18 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
 {
     /// the maximum number of entries to which values will be drawn
     /// (entry numbers greater than this value will cause value-labels to disappear)
-    @objc internal var _maxVisibleCount = 100
+    internal var _maxVisibleCount = 100
     
     /// flag that indicates if auto scaling on the y axis is enabled
-    fileprivate var _autoScaleMinMaxEnabled = false
+    private var _autoScaleMinMaxEnabled = false
     
-    fileprivate var _pinchZoomEnabled = false
-    fileprivate var _doubleTapToZoomEnabled = true
-    fileprivate var _dragXEnabled = true
-    fileprivate var _dragYEnabled = true
+    private var _pinchZoomEnabled = false
+    private var _doubleTapToZoomEnabled = true
+    private var _dragXEnabled = true
+    private var _dragYEnabled = true
     
-    fileprivate var _scaleXEnabled = true
-    fileprivate var _scaleYEnabled = true
+    private var _scaleXEnabled = true
+    private var _scaleYEnabled = true
     
     /// the color for the background of the chart-drawing area (everything behind the grid lines).
     @objc open var gridBackgroundColor = NSUIColor(red: 240/255.0, green: 240/255.0, blue: 240/255.0, alpha: 1.0)
@@ -58,28 +58,28 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
     @objc open var keepPositionOnRotation: Bool = false
     
     /// the object representing the left y-axis
-    @objc internal var _leftAxis: YAxis!
+    internal var _leftAxis: YAxis!
     
     /// the object representing the right y-axis
-    @objc internal var _rightAxis: YAxis!
+    internal var _rightAxis: YAxis!
 
-    @objc internal var _leftYAxisRenderer: YAxisRenderer!
-    @objc internal var _rightYAxisRenderer: YAxisRenderer!
+    internal var _leftYAxisRenderer: YAxisRenderer!
+    internal var _rightYAxisRenderer: YAxisRenderer!
     
-    @objc internal var _leftAxisTransformer: Transformer!
-    @objc internal var _rightAxisTransformer: Transformer!
+    internal var _leftAxisTransformer: Transformer!
+    internal var _rightAxisTransformer: Transformer!
     
-    @objc internal var _xAxisRenderer: XAxisRenderer!
+    internal var _xAxisRenderer: XAxisRenderer!
     
-    @objc internal var _tapGestureRecognizer: NSUITapGestureRecognizer!
-    @objc internal var _doubleTapGestureRecognizer: NSUITapGestureRecognizer!
+    internal var _tapGestureRecognizer: NSUITapGestureRecognizer!
+    internal var _doubleTapGestureRecognizer: NSUITapGestureRecognizer!
     #if !os(tvOS)
-    @objc internal var _pinchGestureRecognizer: NSUIPinchGestureRecognizer!
+    internal var _pinchGestureRecognizer: NSUIPinchGestureRecognizer!
     #endif
-    @objc internal var _panGestureRecognizer: NSUIPanGestureRecognizer!
+    internal var _panGestureRecognizer: NSUIPanGestureRecognizer!
     
     /// flag that indicates if a custom viewport offset has been set
-    fileprivate var _customViewPortEnabled = false
+    private var _customViewPortEnabled = false
     
     public override init(frame: CGRect)
     {
@@ -156,7 +156,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         }
         else
         {
-            let _ = viewPortHandler.refresh(newMatrix: viewPortHandler.touchMatrix, chart: self, invalidate: true)
+            viewPortHandler.refresh(newMatrix: viewPortHandler.touchMatrix, chart: self, invalidate: true)
         }
     }
     
@@ -272,11 +272,11 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         drawMarkers(context: context)
     }
     
-    fileprivate var _autoScaleLastLowestVisibleX: Double?
-    fileprivate var _autoScaleLastHighestVisibleX: Double?
+    private var _autoScaleLastLowestVisibleX: Double?
+    private var _autoScaleLastHighestVisibleX: Double?
     
     /// Performs auto scaling of the axis by recalculating the minimum and maximum y-values based on the entries currently in view.
-    @objc internal func autoScale()
+    internal func autoScale()
     {
         guard let data = _data
             else { return }
@@ -300,13 +300,13 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         calculateOffsets()
     }
     
-    @objc internal func prepareValuePxMatrix()
+    internal func prepareValuePxMatrix()
     {
         _rightAxisTransformer.prepareMatrixValuePx(chartXMin: _xAxis._axisMinimum, deltaX: CGFloat(xAxis.axisRange), deltaY: CGFloat(_rightAxis.axisRange), chartYMin: _rightAxis._axisMinimum)
         _leftAxisTransformer.prepareMatrixValuePx(chartXMin: xAxis._axisMinimum, deltaX: CGFloat(xAxis.axisRange), deltaY: CGFloat(_leftAxis.axisRange), chartYMin: _leftAxis._axisMinimum)
     }
     
-    @objc internal func prepareOffsetMatrix()
+    internal func prepareOffsetMatrix()
     {
         _rightAxisTransformer.prepareMatrixOffset(inverted: _rightAxis.isInverted)
         _leftAxisTransformer.prepareMatrixOffset(inverted: _leftAxis.isInverted)
@@ -468,7 +468,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
     }
     
     /// draws the grid background
-    @objc internal func drawGridBackground(context: CGContext)
+    internal func drawGridBackground(context: CGContext)
     {
         if drawGridBackgroundEnabled || drawBordersEnabled
         {
@@ -497,27 +497,27 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
     
     // MARK: - Gestures
     
-    fileprivate enum GestureScaleAxis
+    private enum GestureScaleAxis
     {
         case both
         case x
         case y
     }
     
-    fileprivate var _isDragging = false
-    fileprivate var _isScaling = false
-    fileprivate var _gestureScaleAxis = GestureScaleAxis.both
-    fileprivate var _closestDataSetToTouch: IChartDataSet!
-    fileprivate var _panGestureReachedEdge: Bool = false
-    fileprivate weak var _outerScrollView: NSUIScrollView?
+    private var _isDragging = false
+    private var _isScaling = false
+    private var _gestureScaleAxis = GestureScaleAxis.both
+    private var _closestDataSetToTouch: IChartDataSet!
+    private var _panGestureReachedEdge: Bool = false
+    private weak var _outerScrollView: NSUIScrollView?
     
-    fileprivate var _lastPanPoint = CGPoint() /// This is to prevent using setTranslation which resets velocity
+    private var _lastPanPoint = CGPoint() /// This is to prevent using setTranslation which resets velocity
     
-    fileprivate var _decelerationLastTime: TimeInterval = 0.0
-    fileprivate var _decelerationDisplayLink: NSUIDisplayLink!
-    fileprivate var _decelerationVelocity = CGPoint()
+    private var _decelerationLastTime: TimeInterval = 0.0
+    private var _decelerationDisplayLink: NSUIDisplayLink!
+    private var _decelerationVelocity = CGPoint()
     
-    @objc fileprivate func tapGestureRecognized(_ recognizer: NSUITapGestureRecognizer)
+    @objc private func tapGestureRecognized(_ recognizer: NSUITapGestureRecognizer)
     {
         if _data === nil
         {
@@ -543,7 +543,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         }
     }
     
-    @objc fileprivate func doubleTapGestureRecognized(_ recognizer: NSUITapGestureRecognizer)
+    @objc private func doubleTapGestureRecognized(_ recognizer: NSUITapGestureRecognizer)
     {
         if _data === nil
         {
@@ -572,7 +572,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
     }
     
     #if !os(tvOS)
-    @objc fileprivate func pinchGestureRecognized(_ recognizer: NSUIPinchGestureRecognizer)
+    @objc private func pinchGestureRecognized(_ recognizer: NSUIPinchGestureRecognizer)
     {
         if recognizer.state == NSUIGestureRecognizerState.began
         {
@@ -648,7 +648,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
                     
                     matrix = _viewPortHandler.touchMatrix.concatenating(matrix)
                     
-                    let _ = _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: true)
+                    _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: true)
                     
                     if delegate !== nil
                     {
@@ -662,7 +662,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
     }
     #endif
     
-    @objc fileprivate func panGestureRecognized(_ recognizer: NSUIPanGestureRecognizer)
+    @objc private func panGestureRecognized(_ recognizer: NSUIPanGestureRecognizer)
     {
         if recognizer.state == NSUIGestureRecognizerState.began && recognizer.nsuiNumberOfTouches() > 0
         {
@@ -783,7 +783,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         }
     }
     
-    fileprivate func performPanChange(translation: CGPoint) -> Bool
+    private func performPanChange(translation: CGPoint) -> Bool
     {
         var translation = translation
         
@@ -815,7 +815,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         return matrix.tx != originalMatrix.tx || matrix.ty != originalMatrix.ty
     }
     
-    fileprivate func isTouchInverted() -> Bool
+    private func isTouchInverted() -> Bool
     {
         return isAnyAxisInverted &&
             _closestDataSetToTouch !== nil &&
@@ -831,7 +831,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         }
     }
     
-    @objc fileprivate func decelerationLoop()
+    @objc private func decelerationLoop()
     {
         let currentTime = CACurrentMediaTime()
         
@@ -864,13 +864,15 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         }
     }
     
-    fileprivate func nsuiGestureRecognizerShouldBegin(_ gestureRecognizer: NSUIGestureRecognizer) -> Bool
+    private func nsuiGestureRecognizerShouldBegin(_ gestureRecognizer: NSUIGestureRecognizer) -> Bool
     {
         if gestureRecognizer == _panGestureRecognizer
         {
-            if _data === nil ||
-                !isDragEnabled ||
-                (self.hasNoDragOffset && self.isFullyZoomedOut && !self.isHighlightPerDragEnabled)
+            let velocity = _panGestureRecognizer.velocity(in: self)
+            if _data === nil || !isDragEnabled ||
+                (self.hasNoDragOffset && self.isFullyZoomedOut && !self.isHighlightPerDragEnabled) ||
+                (!_dragYEnabled && fabs(velocity.y) > fabs(velocity.x)) ||
+                (!_dragXEnabled && fabs(velocity.y) < fabs(velocity.x))
             {
                 return false
             }
@@ -913,30 +915,27 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
     open func gestureRecognizer(_ gestureRecognizer: NSUIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: NSUIGestureRecognizer) -> Bool
     {
         #if !os(tvOS)
-            if ((gestureRecognizer.isKind(of: NSUIPinchGestureRecognizer.self) &&
-                otherGestureRecognizer.isKind(of: NSUIPanGestureRecognizer.self)) ||
-                (gestureRecognizer.isKind(of: NSUIPanGestureRecognizer.self) &&
-                    otherGestureRecognizer.isKind(of: NSUIPinchGestureRecognizer.self)))
+            if ((gestureRecognizer is NSUIPinchGestureRecognizer && otherGestureRecognizer is NSUIPanGestureRecognizer) ||
+                (gestureRecognizer is NSUIPanGestureRecognizer && otherGestureRecognizer is NSUIPinchGestureRecognizer))
             {
                 return true
             }
         #endif
         
-        if (gestureRecognizer.isKind(of: NSUIPanGestureRecognizer.self) &&
-            otherGestureRecognizer.isKind(of: NSUIPanGestureRecognizer.self) && (
-                gestureRecognizer == _panGestureRecognizer
-            ))
+        if gestureRecognizer is NSUIPanGestureRecognizer,
+            otherGestureRecognizer is NSUIPanGestureRecognizer,
+            gestureRecognizer == _panGestureRecognizer
         {
             var scrollView = self.superview
-            while !(scrollView?.isKind(of: NSUIScrollView.self) ?? true)
+            while scrollView != nil && !(scrollView is NSUIScrollView)
             {
                 scrollView = scrollView?.superview
             }
             
             // If there is two scrollview together, we pick the superview of the inner scrollview.
             // In the case of UITableViewWrepperView, the superview will be UITableView
-            if let superViewOfScrollView = scrollView?.superview
-                , superViewOfScrollView.isKind(of: NSUIScrollView.self)
+            if let superViewOfScrollView = scrollView?.superview,
+                superViewOfScrollView is NSUIScrollView
             {
                 scrollView = superViewOfScrollView
             }
@@ -971,7 +970,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         let center = _viewPortHandler.contentCenter
         
         let matrix = _viewPortHandler.zoomIn(x: center.x, y: -center.y)
-        let _ = _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
+        _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
         
         // Range might have changed, which means that Y-axis labels could have changed in size, affecting Y-axis size. So we need to recalculate offsets.
         calculateOffsets()
@@ -984,7 +983,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
         let center = _viewPortHandler.contentCenter
         
         let matrix = _viewPortHandler.zoomOut(x: center.x, y: -center.y)
-        let _ = _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
+        _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
 
         // Range might have changed, which means that Y-axis labels could have changed in size, affecting Y-axis size. So we need to recalculate offsets.
         calculateOffsets()
@@ -995,7 +994,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
     @objc open func resetZoom()
     {
         let matrix = _viewPortHandler.resetZoom()
-        let _ = _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
+        _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
         
         // Range might have changed, which means that Y-axis labels could have changed in size, affecting Y-axis size. So we need to recalculate offsets.
         calculateOffsets()
@@ -1016,7 +1015,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
                y: CGFloat)
     {
         let matrix = _viewPortHandler.zoom(scaleX: scaleX, scaleY: scaleY, x: x, y: -y)
-        let _ = _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
+        _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
         
         // Range might have changed, which means that Y-axis labels could have changed in size, affecting Y-axis size. So we need to recalculate offsets.
         calculateOffsets()
@@ -1067,7 +1066,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
             scaleY: scaleY,
             x: center.x,
             y: -center.y)
-        let _ = viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
+        viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
     }
     
     /// Zooms by the specified scale factor to the specified values on the specified axis.
@@ -1157,7 +1156,7 @@ open class BarLineChartViewBase: ChartViewBase, BarLineScatterCandleBubbleChartD
     @objc open func fitScreen()
     {
         let matrix = _viewPortHandler.fitScreen()
-        let _ = _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
+        _viewPortHandler.refresh(newMatrix: matrix, chart: self, invalidate: false)
         
         calculateOffsets()
         setNeedsDisplay()
diff --git a/Source/Charts/Charts/ChartViewBase.swift b/Source/Charts/Charts/ChartViewBase.swift
index 0c79db9d74..41426689b6 100755
--- a/Source/Charts/Charts/ChartViewBase.swift
+++ b/Source/Charts/Charts/ChartViewBase.swift
@@ -48,26 +48,26 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
     }
     
     /// The default IValueFormatter that has been determined by the chart considering the provided minimum and maximum values.
-    @objc internal var _defaultValueFormatter: IValueFormatter? = DefaultValueFormatter(decimals: 0)
+    internal var _defaultValueFormatter: IValueFormatter? = DefaultValueFormatter(decimals: 0)
     
     /// object that holds all data that was originally set for the chart, before it was modified or any filtering algorithms had been applied
-    @objc internal var _data: ChartData?
+    internal var _data: ChartData?
     
     /// Flag that indicates if highlighting per tap (touch) is enabled
-    fileprivate var _highlightPerTapEnabled = true
+    private var _highlightPerTapEnabled = true
     
     /// If set to true, chart continues to scroll after touch up
     @objc open var dragDecelerationEnabled = true
     
     /// Deceleration friction coefficient in [0 ; 1] interval, higher values indicate that speed will decrease slowly, for example if it set to 0, it will stop immediately.
     /// 1 is an invalid value, and will be converted to 0.999 automatically.
-    fileprivate var _dragDecelerationFrictionCoef: CGFloat = 0.9
+    private var _dragDecelerationFrictionCoef: CGFloat = 0.9
     
     /// if true, units are drawn next to the values in the chart
-    @objc internal var _drawUnitInChart = false
+    internal var _drawUnitInChart = false
     
     /// The object representing the labels on the x-axis
-    @objc internal var _xAxis: XAxis!
+    internal var _xAxis: XAxis!
     
     /// The `Description` object of the chart.
     /// This should have been called just "description", but
@@ -126,7 +126,7 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
     }
     
     /// The legend object containing all data associated with the legend
-    @objc internal var _legend: Legend!
+    internal var _legend: Legend!
     
     /// delegate to receive chart events
     @objc open weak var delegate: ChartViewDelegate?
@@ -140,7 +140,7 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
     /// color of the no data text
     @objc open var noDataTextColor: NSUIColor = NSUIColor.black
     
-    @objc internal var _legendRenderer: LegendRenderer!
+    internal var _legendRenderer: LegendRenderer!
     
     /// object responsible for rendering the data
     @objc open var renderer: DataRenderer?
@@ -148,16 +148,16 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
     @objc open var highlighter: IHighlighter?
     
     /// object that manages the bounds and drawing constraints of the chart
-    @objc internal var _viewPortHandler: ViewPortHandler!
+    internal var _viewPortHandler: ViewPortHandler!
     
     /// object responsible for animations
-    @objc internal var _animator: Animator!
+    internal var _animator: Animator!
     
     /// flag that indicates if offsets calculation has already been done or not
-    fileprivate var _offsetsCalculated = false
+    private var _offsetsCalculated = false
 	
     /// array of Highlight objects that reference the highlighted slices in the chart
-    @objc internal var _indicesToHighlight = [Highlight]()
+    internal var _indicesToHighlight = [Highlight]()
     
     /// `true` if drawing the marker is enabled when tapping on values
     /// (use the `marker` property to specify a marker)
@@ -170,7 +170,7 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
     /// The marker that is displayed when a value is clicked on the chart
     @objc open var marker: IMarker?
     
-    fileprivate var _interceptTouchEvents = false
+    private var _interceptTouchEvents = false
     
     /// An extra offset to be appended to the viewport's top
     @objc open var extraTopOffset: CGFloat = 0.0
@@ -212,7 +212,7 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
         self.removeObserver(self, forKeyPath: "frame")
     }
     
-    @objc internal func initialize()
+    internal func initialize()
     {
         #if os(iOS)
             self.backgroundColor = NSUIColor.clear
@@ -221,8 +221,7 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
         _animator = Animator()
         _animator.delegate = self
 
-        _viewPortHandler = ViewPortHandler()
-        _viewPortHandler.setChartDimens(width: bounds.size.width, height: bounds.size.height)
+        _viewPortHandler = ViewPortHandler(width: bounds.size.width, height: bounds.size.height)
         
         chartDescription = Description()
         
@@ -311,19 +310,19 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
     }
     
     /// Calculates the offsets of the chart to the border depending on the position of an eventual legend or depending on the length of the y-axis and x-axis labels and their position
-    @objc internal func calculateOffsets()
+    internal func calculateOffsets()
     {
         fatalError("calculateOffsets() cannot be called on ChartViewBase")
     }
     
     /// calcualtes the y-min and y-max value and the y-delta and x-delta value
-    @objc internal func calcMinMax()
+    internal func calcMinMax()
     {
         fatalError("calcMinMax() cannot be called on ChartViewBase")
     }
     
     /// calculates the required number of digits for the values that might be drawn in the chart (if enabled), and creates the default value formatter
-    @objc internal func setupDefaultFormatter(min: Double, max: Double)
+    internal func setupDefaultFormatter(min: Double, max: Double)
     {
         // check if a custom formatter is set or not
         var reference = Double(0.0)
@@ -384,7 +383,7 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
     }
     
     /// Draws the description text in the bottom right corner of the chart (per default)
-    @objc internal func drawDescription(context: CGContext)
+    internal func drawDescription(context: CGContext)
     {
         // check if description should be drawn
         guard
@@ -587,7 +586,7 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
     // MARK: - Markers
 
     /// draws all MarkerViews on the highlighted positions
-    @objc internal func drawMarkers(context: CGContext)
+    internal func drawMarkers(context: CGContext)
     {
         // if there is no marker view or drawing marker is disabled
         guard
@@ -886,7 +885,7 @@ open class ChartViewBase: NSUIView, ChartDataProvider, AnimatorDelegate
 		return true
     }
     
-    @objc internal var _viewportJobs = [ViewPortJob]()
+    internal var _viewportJobs = [ViewPortJob]()
     
     open override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?)
     {
diff --git a/Source/Charts/Charts/CombinedChartView.swift b/Source/Charts/Charts/CombinedChartView.swift
index eef738f58b..ead6c3d130 100644
--- a/Source/Charts/Charts/CombinedChartView.swift
+++ b/Source/Charts/Charts/CombinedChartView.swift
@@ -16,7 +16,7 @@ import CoreGraphics
 open class CombinedChartView: BarLineChartViewBase, CombinedChartDataProvider
 {
     /// the fill-formatter used for determining the position of the fill-line
-    @objc internal var _fillFormatter: IFillFormatter!
+    internal var _fillFormatter: IFillFormatter!
     
     /// enum that allows to specify the order in which the different data objects for the combined-chart are drawn
     @objc(CombinedChartDrawOrder)
diff --git a/Source/Charts/Charts/PieChartView.swift b/Source/Charts/Charts/PieChartView.swift
index 7316c2fe03..046253b424 100755
--- a/Source/Charts/Charts/PieChartView.swift
+++ b/Source/Charts/Charts/PieChartView.swift
@@ -20,57 +20,57 @@ import CoreGraphics
 open class PieChartView: PieRadarChartViewBase
 {
     /// rect object that represents the bounds of the piechart, needed for drawing the circle
-    fileprivate var _circleBox = CGRect()
+    private var _circleBox = CGRect()
     
     /// flag indicating if entry labels should be drawn or not
-    fileprivate var _drawEntryLabelsEnabled = true
+    private var _drawEntryLabelsEnabled = true
     
     /// array that holds the width of each pie-slice in degrees
-    fileprivate var _drawAngles = [CGFloat]()
+    private var _drawAngles = [CGFloat]()
     
     /// array that holds the absolute angle in degrees of each slice
-    fileprivate var _absoluteAngles = [CGFloat]()
+    private var _absoluteAngles = [CGFloat]()
     
     /// if true, the hole inside the chart will be drawn
-    fileprivate var _drawHoleEnabled = true
+    private var _drawHoleEnabled = true
     
-    fileprivate var _holeColor: NSUIColor? = NSUIColor.white
+    private var _holeColor: NSUIColor? = NSUIColor.white
     
     /// Sets the color the entry labels are drawn with.
-    fileprivate var _entryLabelColor: NSUIColor? = NSUIColor.white
+    private var _entryLabelColor: NSUIColor? = NSUIColor.white
     
     /// Sets the font the entry labels are drawn with.
-    fileprivate var _entryLabelFont: NSUIFont? = NSUIFont(name: "HelveticaNeue", size: 13.0)
+    private var _entryLabelFont: NSUIFont? = NSUIFont(name: "HelveticaNeue", size: 13.0)
     
     /// if true, the hole will see-through to the inner tips of the slices
-    fileprivate var _drawSlicesUnderHoleEnabled = false
+    private var _drawSlicesUnderHoleEnabled = false
     
     /// if true, the values inside the piechart are drawn as percent values
-    fileprivate var _usePercentValuesEnabled = false
+    private var _usePercentValuesEnabled = false
     
     /// variable for the text that is drawn in the center of the pie-chart
-    fileprivate var _centerAttributedText: NSAttributedString?
+    private var _centerAttributedText: NSAttributedString?
     
     /// the offset on the x- and y-axis the center text has in dp.
-    fileprivate var _centerTextOffset: CGPoint = CGPoint()
+    private var _centerTextOffset: CGPoint = CGPoint()
     
     /// indicates the size of the hole in the center of the piechart
     ///
     /// **default**: `0.5`
-    fileprivate var _holeRadiusPercent = CGFloat(0.5)
+    private var _holeRadiusPercent = CGFloat(0.5)
     
-    fileprivate var _transparentCircleColor: NSUIColor? = NSUIColor(white: 1.0, alpha: 105.0/255.0)
+    private var _transparentCircleColor: NSUIColor? = NSUIColor(white: 1.0, alpha: 105.0/255.0)
     
     /// the radius of the transparent circle next to the chart-hole in the center
-    fileprivate var _transparentCircleRadiusPercent = CGFloat(0.55)
+    private var _transparentCircleRadiusPercent = CGFloat(0.55)
     
     /// if enabled, centertext is drawn
-    fileprivate var _drawCenterTextEnabled = true
+    private var _drawCenterTextEnabled = true
     
-    fileprivate var _centerTextRadiusPercent: CGFloat = 1.0
+    private var _centerTextRadiusPercent: CGFloat = 1.0
     
     /// maximum angle for this pie
-    fileprivate var _maxAngle: CGFloat = 360.0
+    private var _maxAngle: CGFloat = 360.0
 
     public override init(frame: CGRect)
     {
@@ -175,14 +175,14 @@ open class PieChartView: PieRadarChartViewBase
         let offset = drawAngles[entryIndex] / 2.0
         
         // calculate the text position
-        let x: CGFloat = (r * cos(((rotationAngle + absoluteAngles[entryIndex] - offset) * CGFloat(_animator.phaseY)) * ChartUtils.Math.FDEG2RAD) + center.x)
-        let y: CGFloat = (r * sin(((rotationAngle + absoluteAngles[entryIndex] - offset) * CGFloat(_animator.phaseY)) * ChartUtils.Math.FDEG2RAD) + center.y)
+        let x: CGFloat = (r * cos(((rotationAngle + absoluteAngles[entryIndex] - offset) * CGFloat(_animator.phaseY)).DEG2RAD) + center.x)
+        let y: CGFloat = (r * sin(((rotationAngle + absoluteAngles[entryIndex] - offset) * CGFloat(_animator.phaseY)).DEG2RAD) + center.y)
         
         return CGPoint(x: x, y: y)
     }
     
     /// calculates the needed angles for the chart slices
-    fileprivate func calcAngles()
+    private func calcAngles()
     {
         _drawAngles = [CGFloat]()
         _absoluteAngles = [CGFloat]()
@@ -247,13 +247,13 @@ open class PieChartView: PieRadarChartViewBase
     }
     
     /// calculates the needed angle for a given value
-    fileprivate func calcAngle(_ value: Double) -> CGFloat
+    private func calcAngle(_ value: Double) -> CGFloat
     {
         return calcAngle(value: value, yValueSum: (_data as! PieChartData).yValueSum)
     }
     
     /// calculates the needed angle for a given value
-    fileprivate func calcAngle(value: Double, yValueSum: Double) -> CGFloat
+    private func calcAngle(value: Double, yValueSum: Double) -> CGFloat
     {
         return CGFloat(value) / CGFloat(yValueSum) * _maxAngle
     }
@@ -267,7 +267,7 @@ open class PieChartView: PieRadarChartViewBase
     open override func indexForAngle(_ angle: CGFloat) -> Int
     {
         // take the current angle of the chart into consideration
-        let a = ChartUtils.normalizedAngleFromAngle(angle - self.rotationAngle)
+        let a = (angle - self.rotationAngle).normalizedAngle
         for i in 0 ..< _absoluteAngles.count
         {
             if _absoluteAngles[i] > a
diff --git a/Source/Charts/Charts/PieRadarChartViewBase.swift b/Source/Charts/Charts/PieRadarChartViewBase.swift
index b45e2157d3..5d6f22fac8 100755
--- a/Source/Charts/Charts/PieRadarChartViewBase.swift
+++ b/Source/Charts/Charts/PieRadarChartViewBase.swift
@@ -20,10 +20,10 @@ import CoreGraphics
 open class PieRadarChartViewBase: ChartViewBase
 {
     /// holds the normalized version of the current rotation angle of the chart
-    fileprivate var _rotationAngle = CGFloat(270.0)
+    private var _rotationAngle = CGFloat(270.0)
     
     /// holds the raw version of the current rotation angle of the chart
-    fileprivate var _rawRotationAngle = CGFloat(270.0)
+    private var _rawRotationAngle = CGFloat(270.0)
     
     /// flag that indicates if rotation is enabled or not
     @objc open var rotationEnabled = true
@@ -32,11 +32,11 @@ open class PieRadarChartViewBase: ChartViewBase
     @objc open var minOffset = CGFloat(0.0)
 
     /// iOS && OSX only: Enabled multi-touch rotation using two fingers.
-    fileprivate var _rotationWithTwoFingers = false
+    private var _rotationWithTwoFingers = false
     
-    fileprivate var _tapGestureRecognizer: NSUITapGestureRecognizer!
+    private var _tapGestureRecognizer: NSUITapGestureRecognizer!
     #if !os(tvOS)
-    fileprivate var _rotationGestureRecognizer: NSUIRotationGestureRecognizer!
+    private var _rotationGestureRecognizer: NSUIRotationGestureRecognizer!
     #endif
     
     public override init(frame: CGRect)
@@ -226,7 +226,7 @@ open class PieRadarChartViewBase: ChartViewBase
         
         var minOffset = self.minOffset
         
-        if (self.isKind(of: RadarChartView.self))
+        if self is RadarChartView
         {
             let x = self.xAxis
             
@@ -255,7 +255,7 @@ open class PieRadarChartViewBase: ChartViewBase
         let length = sqrt(tx * tx + ty * ty)
         let r = acos(ty / length)
 
-        var angle = r * ChartUtils.Math.RAD2DEG
+        var angle = r.RAD2DEG
 
         if x > c.x
         {
@@ -278,8 +278,8 @@ open class PieRadarChartViewBase: ChartViewBase
     /// from the center, and the angle of the position around the center.
     @objc open func getPosition(center: CGPoint, dist: CGFloat, angle: CGFloat) -> CGPoint
     {
-        return CGPoint(x: center.x + dist * cos(angle * ChartUtils.Math.FDEG2RAD),
-                y: center.y + dist * sin(angle * ChartUtils.Math.FDEG2RAD))
+        return CGPoint(x: center.x + dist * cos(angle.DEG2RAD),
+                y: center.y + dist * sin(angle.DEG2RAD))
     }
 
     /// - returns: The distance of a certain point on the chart to the center of the chart.
@@ -336,7 +336,7 @@ open class PieRadarChartViewBase: ChartViewBase
         set
         {
             _rawRotationAngle = newValue
-            _rotationAngle = ChartUtils.normalizedAngleFromAngle(newValue)
+            _rotationAngle = newValue.normalizedAngle
             setNeedsDisplay()
         }
     }
@@ -366,14 +366,14 @@ open class PieRadarChartViewBase: ChartViewBase
     }
 
     /// - returns: The required offset for the chart legend.
-    @objc internal var requiredLegendOffset: CGFloat
+    internal var requiredLegendOffset: CGFloat
     {
         fatalError("requiredLegendOffset cannot be called on PieRadarChartViewBase")
     }
 
     /// - returns: The base offset needed for the chart without calculating the
     /// legend size.
-    @objc internal var requiredBaseOffset: CGFloat
+    internal var requiredBaseOffset: CGFloat
     {
         fatalError("requiredBaseOffset cannot be called on PieRadarChartViewBase")
     }
@@ -426,7 +426,7 @@ open class PieRadarChartViewBase: ChartViewBase
     
     // MARK: - Animation
     
-    fileprivate var _spinAnimator: Animator!
+    private var _spinAnimator: Animator!
     
     /// Applys a spin animation to the Chart.
     @objc open func spin(duration: TimeInterval, fromAngle: CGFloat, toAngle: CGFloat, easing: ChartEasingFunctionBlock?)
@@ -465,23 +465,23 @@ open class PieRadarChartViewBase: ChartViewBase
     
     // MARK: - Gestures
     
-    fileprivate var _rotationGestureStartPoint: CGPoint!
-    fileprivate var _isRotating = false
-    fileprivate var _startAngle = CGFloat(0.0)
+    private var _rotationGestureStartPoint: CGPoint!
+    private var _isRotating = false
+    private var _startAngle = CGFloat(0.0)
     
-    fileprivate struct AngularVelocitySample
+    private struct AngularVelocitySample
     {
         var time: TimeInterval
         var angle: CGFloat
     }
     
-    fileprivate var _velocitySamples = [AngularVelocitySample]()
+    private var _velocitySamples = [AngularVelocitySample]()
     
-    fileprivate var _decelerationLastTime: TimeInterval = 0.0
-    fileprivate var _decelerationDisplayLink: NSUIDisplayLink!
-    fileprivate var _decelerationAngularVelocity: CGFloat = 0.0
+    private var _decelerationLastTime: TimeInterval = 0.0
+    private var _decelerationDisplayLink: NSUIDisplayLink!
+    private var _decelerationAngularVelocity: CGFloat = 0.0
     
-    @objc internal final func processRotationGestureBegan(location: CGPoint)
+    internal final func processRotationGestureBegan(location: CGPoint)
     {
         self.resetVelocity()
         
@@ -495,7 +495,7 @@ open class PieRadarChartViewBase: ChartViewBase
         _rotationGestureStartPoint = location
     }
     
-    @objc internal final func processRotationGestureMoved(location: CGPoint)
+    internal final func processRotationGestureMoved(location: CGPoint)
     {
         if isDragDecelerationEnabled
         {
@@ -518,7 +518,7 @@ open class PieRadarChartViewBase: ChartViewBase
         }
     }
     
-    @objc internal final func processRotationGestureEnded(location: CGPoint)
+    internal final func processRotationGestureEnded(location: CGPoint)
     {
         if isDragDecelerationEnabled
         {
@@ -537,7 +537,7 @@ open class PieRadarChartViewBase: ChartViewBase
         }
     }
     
-    @objc internal final func processRotationGestureCancelled()
+    internal final func processRotationGestureCancelled()
     {
         if _isRotating
         {
@@ -661,12 +661,12 @@ open class PieRadarChartViewBase: ChartViewBase
     }
     #endif
     
-    fileprivate func resetVelocity()
+    private func resetVelocity()
     {
         _velocitySamples.removeAll(keepingCapacity: false)
     }
     
-    fileprivate func sampleVelocity(touchLocation: CGPoint)
+    private func sampleVelocity(touchLocation: CGPoint)
     {
         let currentTime = CACurrentMediaTime()
         
@@ -691,7 +691,7 @@ open class PieRadarChartViewBase: ChartViewBase
         }
     }
     
-    fileprivate func calculateVelocity() -> CGFloat
+    private func calculateVelocity() -> CGFloat
     {
         if _velocitySamples.isEmpty
         {
@@ -750,7 +750,7 @@ open class PieRadarChartViewBase: ChartViewBase
     }
     
     /// sets the starting angle of the rotation, this is only used by the touch listener, x and y is the touch position
-    fileprivate func setGestureStartAngle(x: CGFloat, y: CGFloat)
+    private func setGestureStartAngle(x: CGFloat, y: CGFloat)
     {
         _startAngle = angleForPoint(x: x, y: y)
         
@@ -759,7 +759,7 @@ open class PieRadarChartViewBase: ChartViewBase
     }
     
     /// updates the view rotation depending on the given touch position, also takes the starting angle into consideration
-    fileprivate func updateGestureRotation(x: CGFloat, y: CGFloat)
+    private func updateGestureRotation(x: CGFloat, y: CGFloat)
     {
         self.rotationAngle = angleForPoint(x: x, y: y) - _startAngle
     }
@@ -773,7 +773,7 @@ open class PieRadarChartViewBase: ChartViewBase
         }
     }
     
-    @objc fileprivate func decelerationLoop()
+    @objc private func decelerationLoop()
     {
         let currentTime = CACurrentMediaTime()
         
@@ -792,7 +792,7 @@ open class PieRadarChartViewBase: ChartViewBase
     }
     
     /// - returns: The distance between two points
-    fileprivate func distance(eventX: CGFloat, startX: CGFloat, eventY: CGFloat, startY: CGFloat) -> CGFloat
+    private func distance(eventX: CGFloat, startX: CGFloat, eventY: CGFloat, startY: CGFloat) -> CGFloat
     {
         let dx = eventX - startX
         let dy = eventY - startY
@@ -800,7 +800,7 @@ open class PieRadarChartViewBase: ChartViewBase
     }
     
     /// - returns: The distance between two points
-    fileprivate func distance(from: CGPoint, to: CGPoint) -> CGFloat
+    private func distance(from: CGPoint, to: CGPoint) -> CGFloat
     {
         let dx = from.x - to.x
         let dy = from.y - to.y
@@ -808,9 +808,9 @@ open class PieRadarChartViewBase: ChartViewBase
     }
     
     /// reference to the last highlighted object
-    fileprivate var _lastHighlight: Highlight!
+    private var _lastHighlight: Highlight!
     
-    @objc fileprivate func tapGestureRecognized(_ recognizer: NSUITapGestureRecognizer)
+    @objc private func tapGestureRecognized(_ recognizer: NSUITapGestureRecognizer)
     {
         if recognizer.state == NSUIGestureRecognizerState.ended
         {
@@ -824,7 +824,7 @@ open class PieRadarChartViewBase: ChartViewBase
     }
     
     #if !os(tvOS)
-    @objc fileprivate func rotationGestureRecognized(_ recognizer: NSUIRotationGestureRecognizer)
+    @objc private func rotationGestureRecognized(_ recognizer: NSUIRotationGestureRecognizer)
     {
         if recognizer.state == NSUIGestureRecognizerState.began
         {
@@ -835,14 +835,14 @@ open class PieRadarChartViewBase: ChartViewBase
         
         if recognizer.state == NSUIGestureRecognizerState.began || recognizer.state == NSUIGestureRecognizerState.changed
         {
-            let angle = ChartUtils.Math.FRAD2DEG * recognizer.nsuiRotation
+            let angle = recognizer.nsuiRotation.RAD2DEG
             
             self.rotationAngle = _startAngle + angle
             setNeedsDisplay()
         }
         else if recognizer.state == NSUIGestureRecognizerState.ended
         {
-            let angle = ChartUtils.Math.FRAD2DEG * recognizer.nsuiRotation
+            let angle = recognizer.nsuiRotation.RAD2DEG
             
             self.rotationAngle = _startAngle + angle
             setNeedsDisplay()
@@ -851,7 +851,7 @@ open class PieRadarChartViewBase: ChartViewBase
             {
                 stopDeceleration()
                 
-                _decelerationAngularVelocity = ChartUtils.Math.FRAD2DEG * recognizer.velocity
+                _decelerationAngularVelocity = recognizer.velocity.RAD2DEG
                 
                 if _decelerationAngularVelocity != 0.0
                 {
diff --git a/Source/Charts/Charts/RadarChartView.swift b/Source/Charts/Charts/RadarChartView.swift
index 232d59492f..2182df6e15 100644
--- a/Source/Charts/Charts/RadarChartView.swift
+++ b/Source/Charts/Charts/RadarChartView.swift
@@ -36,13 +36,13 @@ open class RadarChartView: PieRadarChartViewBase
     @objc open var drawWeb = true
     
     /// modulus that determines how many labels and web-lines are skipped before the next is drawn
-    fileprivate var _skipWebLineCount = 0
+    private var _skipWebLineCount = 0
     
     /// the object reprsenting the y-axis labels
-    fileprivate var _yAxis: YAxis!
+    private var _yAxis: YAxis!
     
-    @objc internal var _yAxisRenderer: YAxisRendererRadarChart!
-    @objc internal var _xAxisRenderer: XAxisRendererRadarChart!
+    internal var _yAxisRenderer: YAxisRendererRadarChart!
+    internal var _xAxisRenderer: XAxisRendererRadarChart!
     
     public override init(frame: CGRect)
     {
@@ -163,7 +163,7 @@ open class RadarChartView: PieRadarChartViewBase
     open override func indexForAngle(_ angle: CGFloat) -> Int
     {
         // take the current angle of the chart into consideration
-        let a = ChartUtils.normalizedAngleFromAngle(angle - self.rotationAngle)
+        let a = (angle - self.rotationAngle).normalizedAngle
         
         let sliceAngle = self.sliceAngle
         
diff --git a/Source/Charts/Components/AxisBase.swift b/Source/Charts/Components/AxisBase.swift
index 0f6c86580d..fbab2c0f71 100644
--- a/Source/Charts/Components/AxisBase.swift
+++ b/Source/Charts/Components/AxisBase.swift
@@ -22,7 +22,7 @@ open class AxisBase: ComponentBase
     }
     
     /// Custom formatter that is used instead of the auto-formatter if set
-    fileprivate var _axisValueFormatter: IAxisValueFormatter?
+    private var _axisValueFormatter: IAxisValueFormatter?
     
     @objc open var labelFont = NSUIFont.systemFont(ofSize: 10.0)
     @objc open var labelTextColor = NSUIColor.black
@@ -44,7 +44,7 @@ open class AxisBase: ComponentBase
     /// flag that indicates of the labels of this axis should be drawn or not
     @objc open var drawLabelsEnabled = true
     
-    fileprivate var _centerAxisLabelsEnabled = false
+    private var _centerAxisLabelsEnabled = false
 
     /// Centers the axis labels instead of drawing them at their original position.
     /// This is useful especially for grouped BarChart.
@@ -60,7 +60,7 @@ open class AxisBase: ComponentBase
     }
 
     /// array of limitlines that can be set for the axis
-    fileprivate var _limitLines = [ChartLimitLine]()
+    private var _limitLines = [ChartLimitLine]()
     
     /// Are the LimitLines drawn behind the data or in front of the data?
     /// 
@@ -82,7 +82,7 @@ open class AxisBase: ComponentBase
     /// the number of label entries the axis should have
     ///
     /// **default**: 6
-    fileprivate var _labelCount = Int(6)
+    private var _labelCount = Int(6)
     
     /// the number of decimal digits to use (for the default formatter
     @objc open var decimals: Int = 0
@@ -93,7 +93,7 @@ open class AxisBase: ComponentBase
     /// If using granularity this could be avoided by having fewer axis values visible.
     @objc open var granularityEnabled = false
     
-    fileprivate var _granularity = Double(1.0)
+    private var _granularity = Double(1.0)
     
     /// The minimum interval between axis values.
     /// This can be used to avoid label duplicating when zooming in.
@@ -195,20 +195,20 @@ open class AxisBase: ComponentBase
     @objc open var spaceMax: Double = 0.0
     
     /// Flag indicating that the axis-min value has been customized
-    @objc internal var _customAxisMin: Bool = false
+    internal var _customAxisMin: Bool = false
     
     /// Flag indicating that the axis-max value has been customized
-    @objc internal var _customAxisMax: Bool = false
+    internal var _customAxisMax: Bool = false
     
     /// Do not touch this directly, instead, use axisMinimum.
     /// This is automatically calculated to represent the real min value,
     /// and is used when calculating the effective minimum.
-    @objc internal var _axisMinimum = Double(0)
+    internal var _axisMinimum = Double(0)
     
     /// Do not touch this directly, instead, use axisMaximum.
     /// This is automatically calculated to represent the real max value,
     /// and is used when calculating the effective maximum.
-    @objc internal var _axisMaximum = Double(0)
+    internal var _axisMaximum = Double(0)
     
     /// the total range of values this axis covers
     @objc open var axisRange = Double(0)
diff --git a/Source/Charts/Components/ChartLimitLine.swift b/Source/Charts/Components/ChartLimitLine.swift
index 8bfd91ccce..d0d2249888 100644
--- a/Source/Charts/Components/ChartLimitLine.swift
+++ b/Source/Charts/Components/ChartLimitLine.swift
@@ -29,7 +29,7 @@ open class ChartLimitLine: ComponentBase
     /// limit / maximum (the y-value or xIndex)
     @objc open var limit = Double(0.0)
     
-    fileprivate var _lineWidth = CGFloat(2.0)
+    private var _lineWidth = CGFloat(2.0)
     @objc open var lineColor = NSUIColor(red: 237.0/255.0, green: 91.0/255.0, blue: 91.0/255.0, alpha: 1.0)
     @objc open var lineDashPhase = CGFloat(0.0)
     @objc open var lineDashLengths: [CGFloat]?
diff --git a/Source/Charts/Components/Legend.swift b/Source/Charts/Components/Legend.swift
index d2d6a1bcf8..992342a329 100644
--- a/Source/Charts/Components/Legend.swift
+++ b/Source/Charts/Components/Legend.swift
@@ -101,7 +101,7 @@ open class Legend: ComponentBase
     /// Are the legend labels/colors a custom value or auto calculated? If false, then it's auto, if true, then custom.
     /// 
     /// **default**: false (automatic legend)
-    fileprivate var _isLegendCustom = false
+    private var _isLegendCustom = false
     
     /// This property is deprecated - Use `horizontalAlignment`, `verticalAlignment`, `orientation`, `drawInside`, `direction`.
     @objc @available(*, deprecated: 1.0, message: "Use `horizontalAlignment`, `verticalAlignment`, `orientation`, `drawInside`, `direction`.")
diff --git a/Source/Charts/Components/YAxis.swift b/Source/Charts/Components/YAxis.swift
index 605a69876d..cfe520776e 100644
--- a/Source/Charts/Components/YAxis.swift
+++ b/Source/Charts/Components/YAxis.swift
@@ -74,7 +74,7 @@ open class YAxis: AxisBase
     @objc open var labelPosition = LabelPosition.outsideChart
     
     /// the side this axis object represents
-    fileprivate var _axisDependency = AxisDependency.left
+    private var _axisDependency = AxisDependency.left
     
     /// the minimum width that the axis should take
     /// 
diff --git a/Source/Charts/Data/Implementations/ChartBaseDataSet.swift b/Source/Charts/Data/Implementations/ChartBaseDataSet.swift
index ea282ffdd1..7136f2f04b 100644
--- a/Source/Charts/Data/Implementations/ChartBaseDataSet.swift
+++ b/Source/Charts/Data/Implementations/ChartBaseDataSet.swift
@@ -270,7 +270,7 @@ open class ChartBaseDataSet: NSObject, IChartDataSet
     open var isHighlightEnabled: Bool { return highlightEnabled }
     
     /// Custom formatter that is used instead of the auto-formatter if set
-    @objc internal var _valueFormatter: IValueFormatter?
+    internal var _valueFormatter: IValueFormatter?
     
     /// Custom formatter that is used instead of the auto-formatter if set
     open var valueFormatter: IValueFormatter?
diff --git a/Source/Charts/Data/Implementations/Standard/BarChartDataEntry.swift b/Source/Charts/Data/Implementations/Standard/BarChartDataEntry.swift
index 89243992ad..23fec77eb8 100644
--- a/Source/Charts/Data/Implementations/Standard/BarChartDataEntry.swift
+++ b/Source/Charts/Data/Implementations/Standard/BarChartDataEntry.swift
@@ -14,16 +14,16 @@ import Foundation
 open class BarChartDataEntry: ChartDataEntry
 {
     /// the values the stacked barchart holds
-    fileprivate var _yVals: [Double]?
+    private var _yVals: [Double]?
     
     /// the ranges for the individual stack values - automatically calculated
-    fileprivate var _ranges: [Range]?
+    private var _ranges: [Range]?
     
     /// the sum of all negative values this entry (if stacked) contains
-    fileprivate var _negativeSum: Double = 0.0
+    private var _negativeSum: Double = 0.0
     
     /// the sum of all positive values this entry (if stacked) contains
-    fileprivate var _positiveSum: Double = 0.0
+    private var _positiveSum: Double = 0.0
     
     public required init()
     {
@@ -240,7 +240,7 @@ open class BarChartDataEntry: ChartDataEntry
     ///
     /// - parameter vals:
     /// - returns:
-    fileprivate static func calcSum(values: [Double]?) -> Double
+    private static func calcSum(values: [Double]?) -> Double
     {
         guard let values = values
             else { return 0.0 }
diff --git a/Source/Charts/Data/Implementations/Standard/BarChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/BarChartDataSet.swift
index ceb5ccb8af..27ed7a5722 100644
--- a/Source/Charts/Data/Implementations/Standard/BarChartDataSet.swift
+++ b/Source/Charts/Data/Implementations/Standard/BarChartDataSet.swift
@@ -15,7 +15,7 @@ import CoreGraphics
 
 open class BarChartDataSet: BarLineScatterCandleBubbleChartDataSet, IBarChartDataSet
 {
-    fileprivate func initialize()
+    private func initialize()
     {
         self.highlightColor = NSUIColor.black
         
@@ -39,14 +39,14 @@ open class BarChartDataSet: BarLineScatterCandleBubbleChartDataSet, IBarChartDat
     
     /// the maximum number of bars that are stacked upon each other, this value
     /// is calculated from the Entries that are added to the DataSet
-    fileprivate var _stackSize = 1
+    private var _stackSize = 1
     
     /// the overall entry count, including counting each stack-value individually
-    fileprivate var _entryCountStacks = 0
+    private var _entryCountStacks = 0
     
     /// Calculates the total number of entries this DataSet represents, including
     /// stacks. All values belonging to a stack are calculated separately.
-    fileprivate func calcEntryCountIncludingStacks(entries: [BarChartDataEntry])
+    private func calcEntryCountIncludingStacks(entries: [BarChartDataEntry])
     {
         _entryCountStacks = 0
         
@@ -64,7 +64,7 @@ open class BarChartDataSet: BarLineScatterCandleBubbleChartDataSet, IBarChartDat
     }
     
     /// calculates the maximum stacksize that occurs in the Entries array of this DataSet
-    fileprivate func calcStackSize(entries: [BarChartDataEntry])
+    private func calcStackSize(entries: [BarChartDataEntry])
     {
         for i in 0 ..< entries.count
         {
diff --git a/Source/Charts/Data/Implementations/Standard/BubbleChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/BubbleChartDataSet.swift
index 6041bb94d3..cdc3567e69 100644
--- a/Source/Charts/Data/Implementations/Standard/BubbleChartDataSet.swift
+++ b/Source/Charts/Data/Implementations/Standard/BubbleChartDataSet.swift
@@ -17,7 +17,7 @@ open class BubbleChartDataSet: BarLineScatterCandleBubbleChartDataSet, IBubbleCh
 {
     // MARK: - Data functions and accessors
     
-    @objc internal var _maxSize = CGFloat(0.0)
+    internal var _maxSize = CGFloat(0.0)
     
     open var maxSize: CGFloat { return _maxSize }
     @objc open var normalizeSizeEnabled: Bool = true
diff --git a/Source/Charts/Data/Implementations/Standard/CandleChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/CandleChartDataSet.swift
index d4da90d69f..852e65d385 100644
--- a/Source/Charts/Data/Implementations/Standard/CandleChartDataSet.swift
+++ b/Source/Charts/Data/Implementations/Standard/CandleChartDataSet.swift
@@ -75,7 +75,7 @@ open class CandleChartDataSet: LineScatterCandleRadarChartDataSet, ICandleChartD
     /// the space between the candle entries
     ///
     /// **default**: 0.1 (10%)
-    fileprivate var _barSpace = CGFloat(0.1)
+    private var _barSpace = CGFloat(0.1)
     
     /// the space that is left out on the left and right side of each candle,
     /// **default**: 0.1 (10%), max 0.45, min 0.0
diff --git a/Source/Charts/Data/Implementations/Standard/ChartData.swift b/Source/Charts/Data/Implementations/Standard/ChartData.swift
index 411643d67f..3b9851a43c 100644
--- a/Source/Charts/Data/Implementations/Standard/ChartData.swift
+++ b/Source/Charts/Data/Implementations/Standard/ChartData.swift
@@ -13,16 +13,16 @@ import Foundation
 
 open class ChartData: NSObject
 {
-    @objc internal var _yMax: Double = -Double.greatestFiniteMagnitude
-    @objc internal var _yMin: Double = Double.greatestFiniteMagnitude
-    @objc internal var _xMax: Double = -Double.greatestFiniteMagnitude
-    @objc internal var _xMin: Double = Double.greatestFiniteMagnitude
-    @objc internal var _leftAxisMax: Double = -Double.greatestFiniteMagnitude
-    @objc internal var _leftAxisMin: Double = Double.greatestFiniteMagnitude
-    @objc internal var _rightAxisMax: Double = -Double.greatestFiniteMagnitude
-    @objc internal var _rightAxisMin: Double = Double.greatestFiniteMagnitude
+    internal var _yMax: Double = -Double.greatestFiniteMagnitude
+    internal var _yMin: Double = Double.greatestFiniteMagnitude
+    internal var _xMax: Double = -Double.greatestFiniteMagnitude
+    internal var _xMin: Double = Double.greatestFiniteMagnitude
+    internal var _leftAxisMax: Double = -Double.greatestFiniteMagnitude
+    internal var _leftAxisMin: Double = Double.greatestFiniteMagnitude
+    internal var _rightAxisMax: Double = -Double.greatestFiniteMagnitude
+    internal var _rightAxisMin: Double = Double.greatestFiniteMagnitude
     
-    @objc internal var _dataSets = [IChartDataSet]()
+    internal var _dataSets = [IChartDataSet]()
     
     public override init()
     {
@@ -45,7 +45,7 @@ open class ChartData: NSObject
         self.init(dataSets: dataSet === nil ? nil : [dataSet!])
     }
     
-    @objc internal func initialize(dataSets: [IChartDataSet])
+    internal func initialize(dataSets: [IChartDataSet])
     {
         notifyDataChanged()
     }
@@ -350,7 +350,7 @@ open class ChartData: NSObject
     /// - parameter type:
     /// - parameter ignorecase: if true, the search is not case-sensitive
     /// - returns: The index of the DataSet Object with the given label. Sensitive or not.
-    @objc internal func getDataSetIndexByLabel(_ label: String, ignorecase: Bool) -> Int
+    internal func getDataSetIndexByLabel(_ label: String, ignorecase: Bool) -> Int
     {
         if ignorecase
         {
@@ -381,7 +381,7 @@ open class ChartData: NSObject
     }
     
     /// - returns: The labels of all DataSets as a string array.
-    @objc internal func dataSetLabels() -> [String]
+    internal func dataSetLabels() -> [String]
     {
         var types = [String]()
         
diff --git a/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift
index b829f630e1..c55ee6fd3d 100644
--- a/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift
+++ b/Source/Charts/Data/Implementations/Standard/ChartDataSet.swift
@@ -55,19 +55,19 @@ open class ChartDataSet: ChartBaseDataSet
     // MARK: - Data functions and accessors
     
     /// the entries that this dataset represents / holds together
-    @objc internal var _values: [ChartDataEntry]!
+    internal var _values: [ChartDataEntry]!
     
     /// maximum y-value in the value array
-    @objc internal var _yMax: Double = -Double.greatestFiniteMagnitude
+    internal var _yMax: Double = -Double.greatestFiniteMagnitude
     
     /// minimum y-value in the value array
-    @objc internal var _yMin: Double = Double.greatestFiniteMagnitude
+    internal var _yMin: Double = Double.greatestFiniteMagnitude
     
     /// maximum x-value in the value array
-    @objc internal var _xMax: Double = -Double.greatestFiniteMagnitude
+    internal var _xMax: Double = -Double.greatestFiniteMagnitude
     
     /// minimum x-value in the value array
-    @objc internal var _xMin: Double = Double.greatestFiniteMagnitude
+    internal var _xMin: Double = Double.greatestFiniteMagnitude
     
     /// *
     /// - note: Calls `notifyDataSetChanged()` after setting a new value.
@@ -158,7 +158,7 @@ open class ChartDataSet: ChartBaseDataSet
     /// Updates the min and max x and y value of this DataSet based on the given Entry.
     ///
     /// - parameter e:
-    @objc internal func calcMinMax(entry e: ChartDataEntry)
+    internal func calcMinMax(entry e: ChartDataEntry)
     {
         calcMinMaxX(entry: e)
         calcMinMaxY(entry: e)
diff --git a/Source/Charts/Data/Implementations/Standard/CombinedChartData.swift b/Source/Charts/Data/Implementations/Standard/CombinedChartData.swift
index 9492f64de9..9e2342a200 100644
--- a/Source/Charts/Data/Implementations/Standard/CombinedChartData.swift
+++ b/Source/Charts/Data/Implementations/Standard/CombinedChartData.swift
@@ -13,11 +13,11 @@ import Foundation
 
 open class CombinedChartData: BarLineScatterCandleBubbleChartData
 {
-    fileprivate var _lineData: LineChartData!
-    fileprivate var _barData: BarChartData!
-    fileprivate var _scatterData: ScatterChartData!
-    fileprivate var _candleData: CandleChartData!
-    fileprivate var _bubbleData: BubbleChartData!
+    private var _lineData: LineChartData!
+    private var _barData: BarChartData!
+    private var _scatterData: ScatterChartData!
+    private var _candleData: CandleChartData!
+    private var _bubbleData: BubbleChartData!
     
     public override init()
     {
diff --git a/Source/Charts/Data/Implementations/Standard/LineChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/LineChartDataSet.swift
index eae20419cb..357d29604f 100644
--- a/Source/Charts/Data/Implementations/Standard/LineChartDataSet.swift
+++ b/Source/Charts/Data/Implementations/Standard/LineChartDataSet.swift
@@ -24,7 +24,7 @@ open class LineChartDataSet: LineRadarChartDataSet, ILineChartDataSet
         case horizontalBezier
     }
     
-    fileprivate func initialize()
+    private func initialize()
     {
         // default color
         circleColors.append(NSUIColor(red: 140.0/255.0, green: 234.0/255.0, blue: 255.0/255.0, alpha: 1.0))
@@ -51,7 +51,7 @@ open class LineChartDataSet: LineRadarChartDataSet, ILineChartDataSet
     /// **default**: Linear
     open var mode: Mode = Mode.linear
     
-    fileprivate var _cubicIntensity = CGFloat(0.2)
+    private var _cubicIntensity = CGFloat(0.2)
     
     /// Intensity for cubic lines (min = 0.05, max = 1)
     ///
@@ -176,7 +176,7 @@ open class LineChartDataSet: LineRadarChartDataSet, ILineChartDataSet
     open var lineCapType = CGLineCap.butt
     
     /// formatter for customizing the position of the fill-line
-    fileprivate var _fillFormatter: IFillFormatter = DefaultFillFormatter()
+    private var _fillFormatter: IFillFormatter = DefaultFillFormatter()
     
     /// Sets a custom IFillFormatter to the chart that handles the position of the filled-line for each DataSet. Set this to null to use the default logic.
     open var fillFormatter: IFillFormatter?
diff --git a/Source/Charts/Data/Implementations/Standard/LineRadarChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/LineRadarChartDataSet.swift
index 4fe67697e9..be934257f1 100644
--- a/Source/Charts/Data/Implementations/Standard/LineRadarChartDataSet.swift
+++ b/Source/Charts/Data/Implementations/Standard/LineRadarChartDataSet.swift
@@ -20,7 +20,7 @@ open class LineRadarChartDataSet: LineScatterCandleRadarChartDataSet, ILineRadar
     // MARK: - Styling functions and accessors
     
     /// The color that is used for filling the line surface area.
-    fileprivate var _fillColor = NSUIColor(red: 140.0/255.0, green: 234.0/255.0, blue: 255.0/255.0, alpha: 1.0)
+    private var _fillColor = NSUIColor(red: 140.0/255.0, green: 234.0/255.0, blue: 255.0/255.0, alpha: 1.0)
     
     /// The color that is used for filling the line surface area.
     open var fillColor: NSUIColor
@@ -41,7 +41,7 @@ open class LineRadarChartDataSet: LineScatterCandleRadarChartDataSet, ILineRadar
     /// **default**: 0.33
     open var fillAlpha = CGFloat(0.33)
     
-    fileprivate var _lineWidth = CGFloat(1.0)
+    private var _lineWidth = CGFloat(1.0)
     
     /// line width of the chart (min = 0.0, max = 10)
     ///
diff --git a/Source/Charts/Data/Implementations/Standard/PieChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/PieChartDataSet.swift
index f7fd919046..af4aa617d0 100644
--- a/Source/Charts/Data/Implementations/Standard/PieChartDataSet.swift
+++ b/Source/Charts/Data/Implementations/Standard/PieChartDataSet.swift
@@ -21,7 +21,7 @@ open class PieChartDataSet: ChartDataSet, IPieChartDataSet
         case outsideSlice
     }
     
-    fileprivate func initialize()
+    private func initialize()
     {
         self.valueTextColor = NSUIColor.white
         self.valueFont = NSUIFont.systemFont(ofSize: 13.0)
@@ -46,7 +46,7 @@ open class PieChartDataSet: ChartDataSet, IPieChartDataSet
     
     // MARK: - Styling functions and accessors
     
-    fileprivate var _sliceSpace = CGFloat(0.0)
+    private var _sliceSpace = CGFloat(0.0)
     
     /// the space in pixels between the pie-slices
     /// **default**: 0
diff --git a/Source/Charts/Data/Implementations/Standard/RadarChartDataSet.swift b/Source/Charts/Data/Implementations/Standard/RadarChartDataSet.swift
index fcb3134fba..67b4730a28 100644
--- a/Source/Charts/Data/Implementations/Standard/RadarChartDataSet.swift
+++ b/Source/Charts/Data/Implementations/Standard/RadarChartDataSet.swift
@@ -15,7 +15,7 @@ import CoreGraphics
 
 open class RadarChartDataSet: LineRadarChartDataSet, IRadarChartDataSet
 {
-    fileprivate func initialize()
+    private func initialize()
     {
         self.valueFont = NSUIFont.systemFont(ofSize: 13.0)
     }
diff --git a/Source/Charts/Filters/DataApproximator.swift b/Source/Charts/Filters/DataApproximator.swift
index 6bc0ee1bd0..6cd5338ff7 100644
--- a/Source/Charts/Filters/DataApproximator.swift
+++ b/Source/Charts/Filters/DataApproximator.swift
@@ -96,7 +96,7 @@ open class DataApproximator: NSObject
         } // else don't keep the point...
     }
     
-    fileprivate class Line
+    private class Line
     {
         var sxey: CGFloat
         var exsy: CGFloat
diff --git a/Source/Charts/Formatters/DefaultValueFormatter.swift b/Source/Charts/Formatters/DefaultValueFormatter.swift
index 0e238bf7a7..b3fff70ac9 100644
--- a/Source/Charts/Formatters/DefaultValueFormatter.swift
+++ b/Source/Charts/Formatters/DefaultValueFormatter.swift
@@ -24,7 +24,7 @@ open class DefaultValueFormatter: NSObject, IValueFormatter
     
     @objc open var hasAutoDecimals: Bool = false
     
-    fileprivate var _formatter: NumberFormatter?
+    private var _formatter: NumberFormatter?
     @objc open var formatter: NumberFormatter?
     {
         get { return _formatter }
@@ -35,7 +35,7 @@ open class DefaultValueFormatter: NSObject, IValueFormatter
         }
     }
     
-    fileprivate var _decimals: Int?
+    private var _decimals: Int?
     open var decimals: Int?
     {
         get { return _decimals }
diff --git a/Source/Charts/Highlight/ChartHighlighter.swift b/Source/Charts/Highlight/ChartHighlighter.swift
index d8e1d0bc4d..719f44e757 100644
--- a/Source/Charts/Highlight/ChartHighlighter.swift
+++ b/Source/Charts/Highlight/ChartHighlighter.swift
@@ -102,7 +102,7 @@ open class ChartHighlighter : NSObject, IHighlighter
     }
     
     /// - returns: An array of `Highlight` objects corresponding to the selected xValue and dataSetIndex.
-    @objc internal func buildHighlights(
+    internal func buildHighlights(
         dataSet set: IChartDataSet,
         dataSetIndex: Int,
         xValue: Double,
@@ -166,7 +166,7 @@ open class ChartHighlighter : NSObject, IHighlighter
     }
     
     /// - returns: The minimum distance from a touch-y-value (in pixels) to the closest y-value (in pixels) that is displayed in the chart.
-    @objc internal func getMinimumDistance(
+    internal func getMinimumDistance(
         closestValues: [Highlight],
         y: CGFloat,
         axis: YAxis.AxisDependency) -> CGFloat
@@ -190,17 +190,17 @@ open class ChartHighlighter : NSObject, IHighlighter
         return distance
     }
     
-    @objc internal func getHighlightPos(high: Highlight) -> CGFloat
+    internal func getHighlightPos(high: Highlight) -> CGFloat
     {
         return high.yPx
     }
     
-    @objc internal func getDistance(x1: CGFloat, y1: CGFloat, x2: CGFloat, y2: CGFloat) -> CGFloat
+    internal func getDistance(x1: CGFloat, y1: CGFloat, x2: CGFloat, y2: CGFloat) -> CGFloat
     {
         return hypot(x1 - x2, y1 - y2)
     }
     
-    @objc internal var data: ChartData?
+    internal var data: ChartData?
     {
         return chart?.data
     }
diff --git a/Source/Charts/Highlight/CombinedHighlighter.swift b/Source/Charts/Highlight/CombinedHighlighter.swift
index 86e841993c..f7ca82f71c 100644
--- a/Source/Charts/Highlight/CombinedHighlighter.swift
+++ b/Source/Charts/Highlight/CombinedHighlighter.swift
@@ -16,7 +16,7 @@ import CoreGraphics
 open class CombinedHighlighter: ChartHighlighter
 {
     /// bar highlighter for supporting stacked highlighting
-    fileprivate var barHighlighter: BarHighlighter?
+    private var barHighlighter: BarHighlighter?
     
     @objc public init(chart: CombinedChartDataProvider, barDataProvider: BarChartDataProvider)
     {
diff --git a/Source/Charts/Highlight/Highlight.swift b/Source/Charts/Highlight/Highlight.swift
index 80778f7663..a33127b8ba 100644
--- a/Source/Charts/Highlight/Highlight.swift
+++ b/Source/Charts/Highlight/Highlight.swift
@@ -22,10 +22,10 @@ open class Highlight: NSObject
     fileprivate var _y = Double.nan
     
     /// the x-pixel of the highlight
-    fileprivate var _xPx = CGFloat.nan
+    private var _xPx = CGFloat.nan
     
     /// the y-pixel of the highlight
-    fileprivate var _yPx = CGFloat.nan
+    private var _yPx = CGFloat.nan
     
     /// the index of the data object - in case it refers to more than one
     @objc open var dataIndex = Int(-1)
@@ -39,7 +39,7 @@ open class Highlight: NSObject
     fileprivate var _stackIndex = Int(-1)
     
     /// the axis the highlighted value belongs to
-    fileprivate var _axis: YAxis.AxisDependency = YAxis.AxisDependency.left
+    private var _axis: YAxis.AxisDependency = YAxis.AxisDependency.left
     
     /// the x-position (pixels) on which this highlight object was last drawn
     @objc open var drawX: CGFloat = 0.0
diff --git a/Source/Charts/Highlight/RadarHighlighter.swift b/Source/Charts/Highlight/RadarHighlighter.swift
index 6e25ac20d1..8df2d3195a 100644
--- a/Source/Charts/Highlight/RadarHighlighter.swift
+++ b/Source/Charts/Highlight/RadarHighlighter.swift
@@ -44,7 +44,7 @@ open class RadarHighlighter: PieRadarHighlighter
     /// The Highlight objects give information about the value at the selected index and DataSet it belongs to.
     ///
     /// - parameter index:
-    @objc internal func getHighlights(forIndex index: Int) -> [Highlight]
+    internal func getHighlights(forIndex index: Int) -> [Highlight]
     {
         var vals = [Highlight]()
         
diff --git a/Source/Charts/Jobs/AnimatedMoveViewJob.swift b/Source/Charts/Jobs/AnimatedMoveViewJob.swift
index b2dc5d2205..b6ea8c28e5 100644
--- a/Source/Charts/Jobs/AnimatedMoveViewJob.swift
+++ b/Source/Charts/Jobs/AnimatedMoveViewJob.swift
@@ -18,28 +18,6 @@ import CoreGraphics
 
 open class AnimatedMoveViewJob: AnimatedViewPortJob
 {
-    public override init(
-        viewPortHandler: ViewPortHandler,
-        xValue: Double,
-        yValue: Double,
-        transformer: Transformer,
-        view: ChartViewBase,
-        xOrigin: CGFloat,
-        yOrigin: CGFloat,
-        duration: TimeInterval,
-        easing: ChartEasingFunctionBlock?)
-    {
-        super.init(viewPortHandler: viewPortHandler,
-            xValue: xValue,
-            yValue: yValue,
-            transformer: transformer,
-            view: view,
-            xOrigin: xOrigin,
-            yOrigin: yOrigin,
-            duration: duration,
-            easing: easing)
-    }
-    
     internal override func animationUpdate()
     {
         guard
diff --git a/Source/Charts/Jobs/AnimatedViewPortJob.swift b/Source/Charts/Jobs/AnimatedViewPortJob.swift
index dbde0bf4b1..7b2cd3e175 100644
--- a/Source/Charts/Jobs/AnimatedViewPortJob.swift
+++ b/Source/Charts/Jobs/AnimatedViewPortJob.swift
@@ -18,16 +18,16 @@ import CoreGraphics
 
 open class AnimatedViewPortJob: ViewPortJob
 {
-    @objc internal var phase: CGFloat = 1.0
-    @objc internal var xOrigin: CGFloat = 0.0
-    @objc internal var yOrigin: CGFloat = 0.0
+    internal var phase: CGFloat = 1.0
+    internal var xOrigin: CGFloat = 0.0
+    internal var yOrigin: CGFloat = 0.0
     
-    fileprivate var _startTime: TimeInterval = 0.0
-    fileprivate var _displayLink: NSUIDisplayLink!
-    fileprivate var _duration: TimeInterval = 0.0
-    fileprivate var _endTime: TimeInterval = 0.0
+    private var _startTime: TimeInterval = 0.0
+    private var _displayLink: NSUIDisplayLink!
+    private var _duration: TimeInterval = 0.0
+    private var _endTime: TimeInterval = 0.0
     
-    fileprivate var _easing: ChartEasingFunctionBlock?
+    private var _easing: ChartEasingFunctionBlock?
     
     @objc public init(
         viewPortHandler: ViewPortHandler,
@@ -71,52 +71,40 @@ open class AnimatedViewPortJob: ViewPortJob
         updateAnimationPhase(_startTime)
         
         _displayLink = NSUIDisplayLink(target: self, selector: #selector(animationLoop))
-        _displayLink.add(to: RunLoop.main, forMode: RunLoopMode.commonModes)
+        _displayLink.add(to: .main, forMode: .commonModes)
     }
     
     @objc open func stop(finish: Bool)
     {
-        if _displayLink != nil
+        guard _displayLink != nil else { return }
+
+        _displayLink.remove(from: .main, forMode: .commonModes)
+        _displayLink = nil
+
+        if finish
         {
-            _displayLink.remove(from: RunLoop.main, forMode: RunLoopMode.commonModes)
-            _displayLink = nil
-            
-            if finish
+            if phase != 1.0
             {
-                if phase != 1.0
-                {
-                    phase = 1.0
-                    phase = 1.0
-                    
-                    animationUpdate()
-                }
-                
-                animationEnd()
+                phase = 1.0
+                animationUpdate()
             }
+
+            animationEnd()
         }
     }
     
-    fileprivate func updateAnimationPhase(_ currentTime: TimeInterval)
+    private func updateAnimationPhase(_ currentTime: TimeInterval)
     {
-        let elapsedTime: TimeInterval = currentTime - _startTime
-        let duration: TimeInterval = _duration
-        var elapsed: TimeInterval = elapsedTime
-        if elapsed > duration
-        {
-            elapsed = duration
-        }
-        
-        if _easing != nil
-        {
-            phase = CGFloat(_easing!(elapsed, duration))
-        }
-        else
-        {
-            phase = CGFloat(elapsed / duration)
-        }
+        let elapsedTime = currentTime - _startTime
+        let duration = _duration
+        var elapsed = elapsedTime
+
+        elapsed = min(elapsed, duration)
+
+        phase = CGFloat(_easing?(elapsed, duration) ?? elapsed / duration)
     }
     
-    @objc fileprivate func animationLoop()
+    @objc private func animationLoop()
     {
         let currentTime: TimeInterval = CACurrentMediaTime()
         
@@ -130,13 +118,13 @@ open class AnimatedViewPortJob: ViewPortJob
         }
     }
     
-    @objc internal func animationUpdate()
+    internal func animationUpdate()
     {
-        // Override this
+        fatalError("`animationUpdate()` must be overriden by subclasses")
     }
     
-    @objc internal func animationEnd()
+    internal func animationEnd()
     {
-        // Override this
+        fatalError("`animationEnd()` must be overriden by subclasses")
     }
 }
diff --git a/Source/Charts/Jobs/AnimatedZoomViewJob.swift b/Source/Charts/Jobs/AnimatedZoomViewJob.swift
index 3ad1959cfc..4e9d5fd981 100644
--- a/Source/Charts/Jobs/AnimatedZoomViewJob.swift
+++ b/Source/Charts/Jobs/AnimatedZoomViewJob.swift
@@ -14,14 +14,14 @@ import CoreGraphics
 
 open class AnimatedZoomViewJob: AnimatedViewPortJob
 {
-    @objc internal var yAxis: YAxis?
-    @objc internal var xAxisRange: Double = 0.0
-    @objc internal var scaleX: CGFloat = 0.0
-    @objc internal var scaleY: CGFloat = 0.0
-    @objc internal var zoomOriginX: CGFloat = 0.0
-    @objc internal var zoomOriginY: CGFloat = 0.0
-    @objc internal var zoomCenterX: CGFloat = 0.0
-    @objc internal var zoomCenterY: CGFloat = 0.0
+    internal var yAxis: YAxis?
+    internal var xAxisRange: Double = 0.0
+    internal var scaleX: CGFloat = 0.0
+    internal var scaleY: CGFloat = 0.0
+    internal var zoomOriginX: CGFloat = 0.0
+    internal var zoomOriginY: CGFloat = 0.0
+    internal var zoomCenterX: CGFloat = 0.0
+    internal var zoomCenterY: CGFloat = 0.0
 
     @objc public init(
         viewPortHandler: ViewPortHandler,
@@ -72,7 +72,7 @@ open class AnimatedZoomViewJob: AnimatedViewPortJob
         let scaleY = yOrigin + (self.scaleY - yOrigin) * phase
         
         var matrix = viewPortHandler.setZoom(scaleX: scaleX, scaleY: scaleY)
-        let _ = viewPortHandler.refresh(newMatrix: matrix, chart: view, invalidate: false)
+        viewPortHandler.refresh(newMatrix: matrix, chart: view, invalidate: false)
         
         let valsInView = CGFloat(yAxis?.axisRange ?? 0.0) / viewPortHandler.scaleY
         let xsInView = CGFloat(xAxisRange) / viewPortHandler.scaleX
@@ -85,7 +85,7 @@ open class AnimatedZoomViewJob: AnimatedViewPortJob
         transformer.pointValueToPixel(&pt)
         
         matrix = viewPortHandler.translate(pt: pt)
-        let _ = viewPortHandler.refresh(newMatrix: matrix, chart: view, invalidate: true)
+        viewPortHandler.refresh(newMatrix: matrix, chart: view, invalidate: true)
     }
     
     internal override func animationEnd()
diff --git a/Source/Charts/Jobs/MoveViewJob.swift b/Source/Charts/Jobs/MoveViewJob.swift
index b175b1707e..acc8165d39 100644
--- a/Source/Charts/Jobs/MoveViewJob.swift
+++ b/Source/Charts/Jobs/MoveViewJob.swift
@@ -18,22 +18,7 @@ import CoreGraphics
 
 @objc(MoveChartViewJob)
 open class MoveViewJob: ViewPortJob
-{
-    public override init(
-        viewPortHandler: ViewPortHandler,
-        xValue: Double,
-        yValue: Double,
-        transformer: Transformer,
-        view: ChartViewBase)
-    {
-        super.init(
-            viewPortHandler: viewPortHandler,
-            xValue: xValue,
-            yValue: yValue,
-            transformer: transformer,
-            view: view)
-    }
-    
+{    
     open override func doJob()
     {
         guard
@@ -43,8 +28,8 @@ open class MoveViewJob: ViewPortJob
             else { return }
         
         var pt = CGPoint(
-            x: CGFloat(xValue),
-            y: CGFloat(yValue)
+            x: xValue,
+            y: yValue
         )
         
         transformer.pointValueToPixel(&pt)
diff --git a/Source/Charts/Jobs/ViewPortJob.swift b/Source/Charts/Jobs/ViewPortJob.swift
index 42f9b76783..c52562ed53 100644
--- a/Source/Charts/Jobs/ViewPortJob.swift
+++ b/Source/Charts/Jobs/ViewPortJob.swift
@@ -16,12 +16,12 @@ import CoreGraphics
 @objc(ChartViewPortJob)
 open class ViewPortJob: NSObject
 {
-    @objc internal var point: CGPoint = CGPoint()
-    @objc internal weak var viewPortHandler: ViewPortHandler?
-    @objc internal var xValue: Double = 0.0
-    @objc internal var yValue: Double = 0.0
-    @objc internal weak var transformer: Transformer?
-    @objc internal weak var view: ChartViewBase?
+    internal var point: CGPoint = CGPoint()
+    internal weak var viewPortHandler: ViewPortHandler?
+    internal var xValue: Double = 0.0
+    internal var yValue: Double = 0.0
+    internal weak var transformer: Transformer?
+    internal weak var view: ChartViewBase?
     
     @objc public init(
         viewPortHandler: ViewPortHandler,
@@ -41,6 +41,6 @@ open class ViewPortJob: NSObject
     
     @objc open func doJob()
     {
-        // Override this
+        fatalError("`doJob()` must be overridden by subclasses")
     }
 }
diff --git a/Source/Charts/Jobs/ZoomViewJob.swift b/Source/Charts/Jobs/ZoomViewJob.swift
index 7a6c8d8911..7bd805c425 100644
--- a/Source/Charts/Jobs/ZoomViewJob.swift
+++ b/Source/Charts/Jobs/ZoomViewJob.swift
@@ -19,9 +19,9 @@ import CoreGraphics
 @objc(ZoomChartViewJob)
 open class ZoomViewJob: ViewPortJob
 {
-    @objc internal var scaleX: CGFloat = 0.0
-    @objc internal var scaleY: CGFloat = 0.0
-    @objc internal var axisDependency: YAxis.AxisDependency = YAxis.AxisDependency.left
+    internal var scaleX: CGFloat = 0.0
+    internal var scaleY: CGFloat = 0.0
+    internal var axisDependency: YAxis.AxisDependency = .left
     
     @objc public init(
         viewPortHandler: ViewPortHandler,
@@ -54,20 +54,20 @@ open class ZoomViewJob: ViewPortJob
             else { return }
         
         var matrix = viewPortHandler.setZoom(scaleX: scaleX, scaleY: scaleY)
-        let _ = viewPortHandler.refresh(newMatrix: matrix, chart: view, invalidate: false)
+        viewPortHandler.refresh(newMatrix: matrix, chart: view, invalidate: false)
         
         let yValsInView = (view as! BarLineChartViewBase).getAxis(axisDependency).axisRange / Double(viewPortHandler.scaleY)
         let xValsInView = (view as! BarLineChartViewBase).xAxis.axisRange / Double(viewPortHandler.scaleX)
         
         var pt = CGPoint(
-            x: CGFloat(xValue - xValsInView / 2.0),
-            y: CGFloat(yValue + yValsInView / 2.0)
+            x: CGFloat(xValue - xValsInView) / 2.0,
+            y: CGFloat(yValue + yValsInView) / 2.0
         )
         
         transformer.pointValueToPixel(&pt)
         
         matrix = viewPortHandler.translate(pt: pt)
-        let _ = viewPortHandler.refresh(newMatrix: matrix, chart: view, invalidate: false)
+        viewPortHandler.refresh(newMatrix: matrix, chart: view, invalidate: false)
         
         (view as! BarLineChartViewBase).calculateOffsets()
         view.setNeedsDisplay()
diff --git a/Source/Charts/Renderers/AxisRendererBase.swift b/Source/Charts/Renderers/AxisRendererBase.swift
index 52a234e011..bd1c6aa466 100644
--- a/Source/Charts/Renderers/AxisRendererBase.swift
+++ b/Source/Charts/Renderers/AxisRendererBase.swift
@@ -20,13 +20,8 @@ open class AxisRendererBase: Renderer
     
     /// transformer to transform values to screen pixels and return
     @objc open var transformer: Transformer?
-    
-    public override init()
-    {
-        super.init()
-    }
-    
-    @objc public init(viewPortHandler: ViewPortHandler?, transformer: Transformer?, axis: AxisBase?)
+
+    @objc public init(viewPortHandler: ViewPortHandler, transformer: Transformer?, axis: AxisBase?)
     {
         super.init(viewPortHandler: viewPortHandler)
         
@@ -68,23 +63,20 @@ open class AxisRendererBase: Renderer
         if let transformer = self.transformer
         {
             // calculate the starting and entry point of the y-labels (depending on zoom / contentrect bounds)
-            if let viewPortHandler = viewPortHandler
+            if viewPortHandler.contentWidth > 10.0 && !viewPortHandler.isFullyZoomedOutY
             {
-                if viewPortHandler.contentWidth > 10.0 && !viewPortHandler.isFullyZoomedOutY
+                let p1 = transformer.valueForTouchPoint(CGPoint(x: viewPortHandler.contentLeft, y: viewPortHandler.contentTop))
+                let p2 = transformer.valueForTouchPoint(CGPoint(x: viewPortHandler.contentLeft, y: viewPortHandler.contentBottom))
+                
+                if !inverted
+                {
+                    min = Double(p2.y)
+                    max = Double(p1.y)
+                }
+                else
                 {
-                    let p1 = transformer.valueForTouchPoint(CGPoint(x: viewPortHandler.contentLeft, y: viewPortHandler.contentTop))
-                    let p2 = transformer.valueForTouchPoint(CGPoint(x: viewPortHandler.contentLeft, y: viewPortHandler.contentBottom))
-                    
-                    if !inverted
-                    {
-                        min = Double(p2.y)
-                        max = Double(p1.y)
-                    }
-                    else
-                    {
-                        min = Double(p1.y)
-                        max = Double(p2.y)
-                    }
+                    min = Double(p1.y)
+                    max = Double(p2.y)
                 }
             }
         }
diff --git a/Source/Charts/Renderers/BarChartRenderer.swift b/Source/Charts/Renderers/BarChartRenderer.swift
index 8aa3bc9b0a..3621ddbf9c 100644
--- a/Source/Charts/Renderers/BarChartRenderer.swift
+++ b/Source/Charts/Renderers/BarChartRenderer.swift
@@ -18,14 +18,14 @@ import CoreGraphics
 
 open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
 {
-    fileprivate class Buffer
+    private class Buffer
     {
         var rects = [CGRect]()
     }
     
     @objc open weak var dataProvider: BarChartDataProvider?
     
-    @objc public init(dataProvider: BarChartDataProvider?, animator: Animator?, viewPortHandler: ViewPortHandler?)
+    @objc public init(dataProvider: BarChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
@@ -33,7 +33,7 @@ open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
     }
     
     // [CGRect] per dataset
-    fileprivate var _buffers = [Buffer]()
+    private var _buffers = [Buffer]()
     
     open override func initBuffers()
     {
@@ -68,12 +68,11 @@ open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
         }
     }
     
-    fileprivate func prepareBuffer(dataSet: IBarChartDataSet, index: Int)
+    private func prepareBuffer(dataSet: IBarChartDataSet, index: Int)
     {
         guard
             let dataProvider = dataProvider,
-            let barData = dataProvider.barData,
-            let animator = animator
+            let barData = dataProvider.barData
             else { return }
         
         let barWidthHalf = barData.barWidth / 2.0
@@ -204,14 +203,11 @@ open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
         }
     }
     
-    fileprivate var _barShadowRectBuffer: CGRect = CGRect()
+    private var _barShadowRectBuffer: CGRect = CGRect()
     
     @objc open func drawDataSet(context: CGContext, dataSet: IBarChartDataSet, index: Int)
     {
-        guard
-            let dataProvider = dataProvider,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let dataProvider = dataProvider else { return }
         
         let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
         
@@ -227,10 +223,7 @@ open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
         // draw the bar shadow before the values
         if dataProvider.isDrawBarShadowEnabled
         {
-            guard
-                let animator = animator,
-                let barData = dataProvider.barData
-                else { return }
+            guard let barData = dataProvider.barData else { return }
             
             let barWidth = barData.barWidth
             let barWidthHalf = barWidth / 2.0
@@ -347,7 +340,7 @@ open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
         rect.size.width = CGFloat(right - left)
         rect.size.height = CGFloat(bottom - top)
         
-        trans.rectValueToPixel(&rect, phaseY: animator?.phaseY ?? 1.0)
+        trans.rectValueToPixel(&rect, phaseY: animator.phaseY )
     }
 
     open override func drawValues(context: CGContext)
@@ -357,18 +350,16 @@ open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
         {
             guard
                 let dataProvider = dataProvider,
-                let viewPortHandler = self.viewPortHandler,
-                let barData = dataProvider.barData,
-                let animator = animator
+                let barData = dataProvider.barData
                 else { return }
-            
+
             var dataSets = barData.dataSets
 
             let valueOffsetPlus: CGFloat = 4.5
             var posOffset: CGFloat
             var negOffset: CGFloat
             let drawValueAboveBar = dataProvider.isDrawValueAboveBarEnabled
-            
+
             for dataSetIndex in 0 ..< barData.dataSetCount
             {
                 guard let dataSet = dataSets[dataSetIndex] as? IBarChartDataSet else { continue }
@@ -693,7 +684,7 @@ open class BarChartRenderer: BarLineScatterCandleBubbleRenderer
     }
     
     /// Sets the drawing position of the highlight object based on the riven bar-rect.
-    @objc internal func setHighlightDrawPos(highlight high: Highlight, barRect: CGRect)
+    internal func setHighlightDrawPos(highlight high: Highlight, barRect: CGRect)
     {
         high.setDraw(x: barRect.midX, y: barRect.origin.y)
     }
diff --git a/Source/Charts/Renderers/BarLineScatterCandleBubbleRenderer.swift b/Source/Charts/Renderers/BarLineScatterCandleBubbleRenderer.swift
index 796c757290..4ba1b5fac7 100644
--- a/Source/Charts/Renderers/BarLineScatterCandleBubbleRenderer.swift
+++ b/Source/Charts/Renderers/BarLineScatterCandleBubbleRenderer.swift
@@ -17,24 +17,16 @@ open class BarLineScatterCandleBubbleRenderer: DataRenderer
 {
     internal var _xBounds = XBounds() // Reusable XBounds object
     
-    public override init(animator: Animator?, viewPortHandler: ViewPortHandler?)
+    public override init(animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
     }
     
     /// Checks if the provided entry object is in bounds for drawing considering the current animation phase.
-    @objc internal func isInBoundsX(entry e: ChartDataEntry, dataSet: IBarLineScatterCandleBubbleChartDataSet) -> Bool
+    internal func isInBoundsX(entry e: ChartDataEntry, dataSet: IBarLineScatterCandleBubbleChartDataSet) -> Bool
     {
         let entryIndex = dataSet.entryIndex(entry: e)
-        
-        if Double(entryIndex) >= Double(dataSet.entryCount) * (animator?.phaseX ?? 1.0)
-        {
-            return false
-        }
-        else
-        {
-            return true
-        }
+        return Double(entryIndex) < Double(dataSet.entryCount) * animator.phaseX
     }
 
     /// Calculates and returns the x-bounds for the given DataSet in terms of index in their values array.
@@ -47,7 +39,7 @@ open class BarLineScatterCandleBubbleRenderer: DataRenderer
     }
     
     /// - returns: `true` if the DataSet values should be drawn, `false` if not.
-    @objc internal func shouldDrawValues(forDataSet set: IChartDataSet) -> Bool
+    internal func shouldDrawValues(forDataSet set: IChartDataSet) -> Bool
     {
         return set.isVisible && (set.isDrawValuesEnabled || set.isDrawIconsEnabled)
     }
@@ -94,5 +86,4 @@ open class BarLineScatterCandleBubbleRenderer: DataRenderer
             range = Int(Double(self.max - self.min) * phaseX)
         }
     }
-
 }
diff --git a/Source/Charts/Renderers/BubbleChartRenderer.swift b/Source/Charts/Renderers/BubbleChartRenderer.swift
index 4f4265db3b..8498070c17 100644
--- a/Source/Charts/Renderers/BubbleChartRenderer.swift
+++ b/Source/Charts/Renderers/BubbleChartRenderer.swift
@@ -21,7 +21,7 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
 {
     @objc open weak var dataProvider: BubbleChartDataProvider?
     
-    @objc public init(dataProvider: BubbleChartDataProvider?, animator: Animator?, viewPortHandler: ViewPortHandler?)
+    @objc public init(dataProvider: BubbleChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
@@ -35,16 +35,13 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
             let bubbleData = dataProvider.bubbleData
             else { return }
         
-        for set in bubbleData.dataSets as! [IBubbleChartDataSet]
+        for set in bubbleData.dataSets as! [IBubbleChartDataSet] where set.isVisible
         {
-            if set.isVisible
-            {
-                drawDataSet(context: context, dataSet: set)
-            }
+            drawDataSet(context: context, dataSet: set)
         }
     }
     
-    fileprivate func getShapeSize(
+    private func getShapeSize(
         entrySize: CGFloat,
         maxSize: CGFloat,
         reference: CGFloat,
@@ -57,16 +54,12 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
         return shapeSize
     }
     
-    fileprivate var _pointBuffer = CGPoint()
-    fileprivate var _sizeBuffer = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _pointBuffer = CGPoint()
+    private var _sizeBuffer = [CGPoint](repeating: CGPoint(), count: 2)
     
     @objc open func drawDataSet(context: CGContext, dataSet: IBubbleChartDataSet)
     {
-        guard
-            let dataProvider = dataProvider,
-            let viewPortHandler = self.viewPortHandler,
-            let animator = animator
-            else { return }
+        guard let dataProvider = dataProvider else { return }
         
         let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
         
@@ -84,6 +77,7 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
         trans.pointValuesToPixel(&_sizeBuffer)
         
         context.saveGState()
+        defer { context.restoreGState() }
         
         let normalizeSize = dataSet.isNormalizeSizeEnabled
         
@@ -103,21 +97,13 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
             let shapeSize = getShapeSize(entrySize: entry.size, maxSize: dataSet.maxSize, reference: referenceSize, normalizeSize: normalizeSize)
             let shapeHalf = shapeSize / 2.0
             
-            if !viewPortHandler.isInBoundsTop(_pointBuffer.y + shapeHalf)
-                || !viewPortHandler.isInBoundsBottom(_pointBuffer.y - shapeHalf)
-            {
-                continue
-            }
-            
-            if !viewPortHandler.isInBoundsLeft(_pointBuffer.x + shapeHalf)
-            {
-                continue
-            }
-            
-            if !viewPortHandler.isInBoundsRight(_pointBuffer.x - shapeHalf)
-            {
-                break
-            }
+            guard
+                viewPortHandler.isInBoundsTop(_pointBuffer.y + shapeHalf),
+                viewPortHandler.isInBoundsBottom(_pointBuffer.y - shapeHalf),
+                viewPortHandler.isInBoundsLeft(_pointBuffer.x + shapeHalf)
+                else { continue }
+
+            guard viewPortHandler.isInBoundsRight(_pointBuffer.x - shapeHalf) else { break }
             
             let color = dataSet.color(atIndex: Int(entry.x))
             
@@ -131,100 +117,86 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
             context.setFillColor(color.cgColor)
             context.fillEllipse(in: rect)
         }
-        
-        context.restoreGState()
     }
     
     open override func drawValues(context: CGContext)
     {
         guard let
             dataProvider = dataProvider,
-            let viewPortHandler = self.viewPortHandler,
             let bubbleData = dataProvider.bubbleData,
-            let animator = animator
+            isDrawingValuesAllowed(dataProvider: dataProvider),
+            let dataSets = bubbleData.dataSets as? [IBubbleChartDataSet]
             else { return }
-        
-        // if values are drawn
-        if isDrawingValuesAllowed(dataProvider: dataProvider)
+
+        let phaseX = max(0.0, min(1.0, animator.phaseX))
+        let phaseY = animator.phaseY
+
+        var pt = CGPoint()
+
+        for i in 0..<dataSets.count
         {
-            guard let dataSets = bubbleData.dataSets as? [IBubbleChartDataSet] else { return }
-            
-            let phaseX = max(0.0, min(1.0, animator.phaseX))
-            let phaseY = animator.phaseY
-            
-            var pt = CGPoint()
-            
-            for i in 0..<dataSets.count
+            let dataSet = dataSets[i]
+
+            guard
+                shouldDrawValues(forDataSet: dataSet),
+                let formatter = dataSet.valueFormatter
+                else { continue }
+
+            let alpha = phaseX == 1 ? phaseY : phaseX
+
+            _xBounds.set(chart: dataProvider, dataSet: dataSet, animator: animator)
+
+            let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
+            let valueToPixelMatrix = trans.valueToPixelMatrix
+
+            let iconsOffset = dataSet.iconsOffset
+
+            for j in _xBounds.min..._xBounds.range + _xBounds.min
             {
-                let dataSet = dataSets[i]
-                
-                if !shouldDrawValues(forDataSet: dataSet)
+                guard let e = dataSet.entryForIndex(j) as? BubbleChartDataEntry else { break }
+
+                let valueTextColor = dataSet.valueTextColorAt(j).withAlphaComponent(CGFloat(alpha))
+
+                pt.x = CGFloat(e.x)
+                pt.y = CGFloat(e.y * phaseY)
+                pt = pt.applying(valueToPixelMatrix)
+
+                guard viewPortHandler.isInBoundsRight(pt.x) else { break }
+
+                guard
+                    viewPortHandler.isInBoundsLeft(pt.x),
+                    viewPortHandler.isInBoundsY(pt.y)
+                    else { continue }
+
+                let text = formatter.stringForValue(
+                    Double(e.size),
+                    entry: e,
+                    dataSetIndex: i,
+                    viewPortHandler: viewPortHandler)
+
+                // Larger font for larger bubbles?
+                let valueFont = dataSet.valueFont
+                let lineHeight = valueFont.lineHeight
+
+                if dataSet.isDrawValuesEnabled
                 {
-                    continue
+                    ChartUtils.drawText(
+                        context: context,
+                        text: text,
+                        point: CGPoint(
+                            x: pt.x,
+                            y: pt.y - (0.5 * lineHeight)),
+                        align: .center,
+                        attributes: [NSAttributedStringKey.font: valueFont, NSAttributedStringKey.foregroundColor: valueTextColor])
                 }
-                
-                let alpha = phaseX == 1 ? phaseY : phaseX
-                
-                guard let formatter = dataSet.valueFormatter else { continue }
-                
-                _xBounds.set(chart: dataProvider, dataSet: dataSet, animator: animator)
-                
-                let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
-                let valueToPixelMatrix = trans.valueToPixelMatrix
-                
-                let iconsOffset = dataSet.iconsOffset
-                
-                for j in stride(from: _xBounds.min, through: _xBounds.range + _xBounds.min, by: 1)
-                {
-                    guard let e = dataSet.entryForIndex(j) as? BubbleChartDataEntry else { break }
-                    
-                    let valueTextColor = dataSet.valueTextColorAt(j).withAlphaComponent(CGFloat(alpha))
-                    
-                    pt.x = CGFloat(e.x)
-                    pt.y = CGFloat(e.y * phaseY)
-                    pt = pt.applying(valueToPixelMatrix)
-                    
-                    if (!viewPortHandler.isInBoundsRight(pt.x))
-                    {
-                        break
-                    }
-                    
-                    if ((!viewPortHandler.isInBoundsLeft(pt.x) || !viewPortHandler.isInBoundsY(pt.y)))
-                    {
-                        continue
-                    }
-                    
-                    let text = formatter.stringForValue(
-                        Double(e.size),
-                        entry: e,
-                        dataSetIndex: i,
-                        viewPortHandler: viewPortHandler)
-                    
-                    // Larger font for larger bubbles?
-                    let valueFont = dataSet.valueFont
-                    let lineHeight = valueFont.lineHeight
 
-                    if dataSet.isDrawValuesEnabled
-                    {
-                        ChartUtils.drawText(
-                            context: context,
-                            text: text,
-                            point: CGPoint(
-                                x: pt.x,
-                                y: pt.y - (0.5 * lineHeight)),
-                            align: .center,
-                            attributes: [NSAttributedStringKey.font: valueFont, NSAttributedStringKey.foregroundColor: valueTextColor])
-                    }
-                    
-                    if let icon = e.icon, dataSet.isDrawIconsEnabled
-                    {
-                         ChartUtils.drawImage(context: context,
-                                              image: icon,
-                                              x: pt.x + iconsOffset.x,
-                                              y: pt.y + iconsOffset.y,
-                                              size: icon.size)
-                    }
-                    
+                if let icon = e.icon, dataSet.isDrawIconsEnabled
+                {
+                    ChartUtils.drawImage(context: context,
+                                         image: icon,
+                                         x: pt.x + iconsOffset.x,
+                                         y: pt.y + iconsOffset.y,
+                                         size: icon.size)
                 }
             }
         }
@@ -237,28 +209,25 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
     
     open override func drawHighlighted(context: CGContext, indices: [Highlight])
     {
-        guard let
-            dataProvider = dataProvider,
-            let viewPortHandler = self.viewPortHandler,
-            let bubbleData = dataProvider.bubbleData,
-            let animator = animator
+        guard
+            let dataProvider = dataProvider,
+            let bubbleData = dataProvider.bubbleData
             else { return }
-        
+
         context.saveGState()
-        
+        defer { context.restoreGState() }
+
         let phaseY = animator.phaseY
         
         for high in indices
         {
             guard
                 let dataSet = bubbleData.getDataSetByIndex(high.dataSetIndex) as? IBubbleChartDataSet,
-                dataSet.isHighlightEnabled
+                dataSet.isHighlightEnabled,
+                let entry = dataSet.entryForXValue(high.x, closestToY: high.y) as? BubbleChartDataEntry,
+                isInBoundsX(entry: entry, dataSet: dataSet)
                 else { continue }
-                        
-            guard let entry = dataSet.entryForXValue(high.x, closestToY: high.y) as? BubbleChartDataEntry else { continue }
-            
-            if !isInBoundsX(entry: entry, dataSet: dataSet) { continue }
-            
+
             let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
             
             _sizeBuffer[0].x = 0.0
@@ -282,22 +251,14 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
             let shapeSize = getShapeSize(entrySize: entry.size, maxSize: dataSet.maxSize, reference: referenceSize, normalizeSize: normalizeSize)
             let shapeHalf = shapeSize / 2.0
             
-            if !viewPortHandler.isInBoundsTop(_pointBuffer.y + shapeHalf) ||
-                !viewPortHandler.isInBoundsBottom(_pointBuffer.y - shapeHalf)
-            {
-                continue
-            }
-            
-            if !viewPortHandler.isInBoundsLeft(_pointBuffer.x + shapeHalf)
-            {
-                continue
-            }
-            
-            if !viewPortHandler.isInBoundsRight(_pointBuffer.x - shapeHalf)
-            {
-                break
-            }
-            
+            guard
+                viewPortHandler.isInBoundsTop(_pointBuffer.y + shapeHalf),
+                viewPortHandler.isInBoundsBottom(_pointBuffer.y - shapeHalf),
+                viewPortHandler.isInBoundsLeft(_pointBuffer.x + shapeHalf)
+            else { continue }
+
+            guard viewPortHandler.isInBoundsRight(_pointBuffer.x - shapeHalf) else { break }
+
             let originalColor = dataSet.color(atIndex: Int(entry.x))
             
             var h: CGFloat = 0.0
@@ -320,7 +281,5 @@ open class BubbleChartRenderer: BarLineScatterCandleBubbleRenderer
             
             high.setDraw(x: _pointBuffer.x, y: _pointBuffer.y)
         }
-        
-        context.restoreGState()
     }
 }
diff --git a/Source/Charts/Renderers/CandleStickChartRenderer.swift b/Source/Charts/Renderers/CandleStickChartRenderer.swift
index 2b897aadf9..28a460d9fe 100644
--- a/Source/Charts/Renderers/CandleStickChartRenderer.swift
+++ b/Source/Charts/Renderers/CandleStickChartRenderer.swift
@@ -21,7 +21,7 @@ open class CandleStickChartRenderer: LineScatterCandleRadarRenderer
 {
     @objc open weak var dataProvider: CandleChartDataProvider?
     
-    @objc public init(dataProvider: CandleChartDataProvider?, animator: Animator?, viewPortHandler: ViewPortHandler?)
+    @objc public init(dataProvider: CandleChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
@@ -41,19 +41,16 @@ open class CandleStickChartRenderer: LineScatterCandleRadarRenderer
         }
     }
     
-    fileprivate var _shadowPoints = [CGPoint](repeating: CGPoint(), count: 4)
-    fileprivate var _rangePoints = [CGPoint](repeating: CGPoint(), count: 2)
-    fileprivate var _openPoints = [CGPoint](repeating: CGPoint(), count: 2)
-    fileprivate var _closePoints = [CGPoint](repeating: CGPoint(), count: 2)
-    fileprivate var _bodyRect = CGRect()
-    fileprivate var _lineSegments = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _shadowPoints = [CGPoint](repeating: CGPoint(), count: 4)
+    private var _rangePoints = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _openPoints = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _closePoints = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _bodyRect = CGRect()
+    private var _lineSegments = [CGPoint](repeating: CGPoint(), count: 2)
     
     @objc open func drawDataSet(context: CGContext, dataSet: ICandleChartDataSet)
     {
-        guard let
-            dataProvider = dataProvider,
-            let animator = animator
-            else { return }
+        guard let dataProvider = dataProvider else { return }
 
         let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
         
@@ -239,9 +236,7 @@ open class CandleStickChartRenderer: LineScatterCandleRadarRenderer
     {
         guard
             let dataProvider = dataProvider,
-            let viewPortHandler = self.viewPortHandler,
-            let candleData = dataProvider.candleData,
-            let animator = animator
+            let candleData = dataProvider.candleData
             else { return }
         
         // if values are drawn
@@ -332,8 +327,7 @@ open class CandleStickChartRenderer: LineScatterCandleRadarRenderer
     {
         guard
             let dataProvider = dataProvider,
-            let candleData = dataProvider.candleData,
-            let animator = animator
+            let candleData = dataProvider.candleData
             else { return }
         
         context.saveGState()
diff --git a/Source/Charts/Renderers/ChartDataRendererBase.swift b/Source/Charts/Renderers/ChartDataRendererBase.swift
index 8204de05b7..024516aa15 100644
--- a/Source/Charts/Renderers/ChartDataRendererBase.swift
+++ b/Source/Charts/Renderers/ChartDataRendererBase.swift
@@ -15,13 +15,13 @@ import CoreGraphics
 @objc(ChartDataRendererBase)
 open class DataRenderer: Renderer
 {
-    @objc open var animator: Animator?
+    @objc open let animator: Animator
     
-    @objc public init(animator: Animator?, viewPortHandler: ViewPortHandler?)
+    @objc public init(animator: Animator, viewPortHandler: ViewPortHandler)
     {
-        super.init(viewPortHandler: viewPortHandler)
-        
         self.animator = animator
+
+        super.init(viewPortHandler: viewPortHandler)
     }
 
     @objc open func drawData(context: CGContext)
@@ -53,8 +53,7 @@ open class DataRenderer: Renderer
     
     @objc open func isDrawingValuesAllowed(dataProvider: ChartDataProvider?) -> Bool
     {
-        guard let data = dataProvider?.data
-            else { return false }
-        return data.entryCount < Int(CGFloat(dataProvider?.maxVisibleCount ?? 0) * (self.viewPortHandler?.scaleX ?? 1.0))
+        guard let data = dataProvider?.data else { return false }
+        return data.entryCount < Int(CGFloat(dataProvider?.maxVisibleCount ?? 0) * viewPortHandler.scaleX)
     }
 }
diff --git a/Source/Charts/Renderers/CombinedChartRenderer.swift b/Source/Charts/Renderers/CombinedChartRenderer.swift
index 72cb1f14d2..d38ccb5f7a 100644
--- a/Source/Charts/Renderers/CombinedChartRenderer.swift
+++ b/Source/Charts/Renderers/CombinedChartRenderer.swift
@@ -22,11 +22,11 @@ open class CombinedChartRenderer: DataRenderer
     /// if set to true, a grey area is drawn behind each bar that indicates the maximum value
     @objc open var drawBarShadowEnabled = false
     
-    @objc internal var _renderers = [DataRenderer]()
+    internal var _renderers = [DataRenderer]()
     
     internal var _drawOrder: [CombinedChartView.DrawOrder] = [.bar, .bubble, .line, .candle, .scatter]
     
-    @objc public init(chart: CombinedChartView?, animator: Animator, viewPortHandler: ViewPortHandler?)
+    @objc public init(chart: CombinedChartView, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
@@ -36,15 +36,11 @@ open class CombinedChartRenderer: DataRenderer
     }
     
     /// Creates the renderers needed for this combined-renderer in the required order. Also takes the DrawOrder into consideration.
-    @objc internal func createRenderers()
+    internal func createRenderers()
     {
         _renderers = [DataRenderer]()
         
-        guard let
-            chart = chart,
-            let animator = animator,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let chart = chart else { return }
 
         for order in drawOrder
         {
diff --git a/Source/Charts/Renderers/HorizontalBarChartRenderer.swift b/Source/Charts/Renderers/HorizontalBarChartRenderer.swift
index 2de854df43..23925c4d60 100644
--- a/Source/Charts/Renderers/HorizontalBarChartRenderer.swift
+++ b/Source/Charts/Renderers/HorizontalBarChartRenderer.swift
@@ -19,18 +19,18 @@ import CoreGraphics
 
 open class HorizontalBarChartRenderer: BarChartRenderer
 {
-    fileprivate class Buffer
+    private class Buffer
     {
         var rects = [CGRect]()
     }
     
-    public override init(dataProvider: BarChartDataProvider?, animator: Animator?, viewPortHandler: ViewPortHandler?)
+    public override init(dataProvider: BarChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(dataProvider: dataProvider, animator: animator, viewPortHandler: viewPortHandler)
     }
     
     // [CGRect] per dataset
-    fileprivate var _buffers = [Buffer]()
+    private var _buffers = [Buffer]()
     
     open override func initBuffers()
     {
@@ -65,12 +65,11 @@ open class HorizontalBarChartRenderer: BarChartRenderer
         }
     }
     
-    fileprivate func prepareBuffer(dataSet: IBarChartDataSet, index: Int)
+    private func prepareBuffer(dataSet: IBarChartDataSet, index: Int)
     {
         guard let
             dataProvider = dataProvider,
-            let barData = dataProvider.barData,
-            let animator = animator
+            let barData = dataProvider.barData
             else { return }
         
         let barWidthHalf = barData.barWidth / 2.0
@@ -178,14 +177,11 @@ open class HorizontalBarChartRenderer: BarChartRenderer
         }
     }
     
-    fileprivate var _barShadowRectBuffer: CGRect = CGRect()
+    private var _barShadowRectBuffer: CGRect = CGRect()
     
     open override func drawDataSet(context: CGContext, dataSet: IBarChartDataSet, index: Int)
     {
-        guard let
-            dataProvider = dataProvider,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let dataProvider = dataProvider else { return }
         
         let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
         
@@ -201,10 +197,7 @@ open class HorizontalBarChartRenderer: BarChartRenderer
         // draw the bar shadow before the values
         if dataProvider.isDrawBarShadowEnabled
         {
-            guard
-                let animator = animator,
-                let barData = dataProvider.barData
-                else { return }
+            guard let barData = dataProvider.barData else { return }
             
             let barWidth = barData.barWidth
             let barWidthHalf = barWidth / 2.0
@@ -299,7 +292,7 @@ open class HorizontalBarChartRenderer: BarChartRenderer
         rect.size.width = CGFloat(right - left)
         rect.size.height = CGFloat(bottom - top)
         
-        trans.rectValueToPixelHorizontal(&rect, phaseY: animator?.phaseY ?? 1.0)
+        trans.rectValueToPixelHorizontal(&rect, phaseY: animator.phaseY)
     }
     
     open override func drawValues(context: CGContext)
@@ -309,9 +302,7 @@ open class HorizontalBarChartRenderer: BarChartRenderer
         {
             guard
                 let dataProvider = dataProvider,
-                let barData = dataProvider.barData,
-                let animator = animator,
-                let viewPortHandler = self.viewPortHandler
+                let barData = dataProvider.barData
                 else { return }
             
             var dataSets = barData.dataSets
@@ -610,7 +601,7 @@ open class HorizontalBarChartRenderer: BarChartRenderer
     {
         guard let data = dataProvider?.data
             else { return false }
-        return data.entryCount < Int(CGFloat(dataProvider?.maxVisibleCount ?? 0) * (self.viewPortHandler?.scaleY ?? 1.0))
+        return data.entryCount < Int(CGFloat(dataProvider?.maxVisibleCount ?? 0) * self.viewPortHandler.scaleY)
     }
     
     /// Sets the drawing position of the highlight object based on the riven bar-rect.
diff --git a/Source/Charts/Renderers/LegendRenderer.swift b/Source/Charts/Renderers/LegendRenderer.swift
index aab91b24ad..38c3648537 100755
--- a/Source/Charts/Renderers/LegendRenderer.swift
+++ b/Source/Charts/Renderers/LegendRenderer.swift
@@ -22,7 +22,7 @@ open class LegendRenderer: Renderer
     /// the legend object this renderer renders
     @objc open var legend: Legend?
 
-    @objc public init(viewPortHandler: ViewPortHandler?, legend: Legend?)
+    @objc public init(viewPortHandler: ViewPortHandler, legend: Legend?)
     {
         super.init(viewPortHandler: viewPortHandler)
         
@@ -32,10 +32,7 @@ open class LegendRenderer: Renderer
     /// Prepares the legend and calculates all needed forms, labels and colors.
     @objc open func computeLegend(data: ChartData)
     {
-        guard
-            let legend = legend,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let legend = legend else { return }
         
         if !legend.isLegendCustom
         {
@@ -194,10 +191,7 @@ open class LegendRenderer: Renderer
     
     @objc open func renderLegend(context: CGContext)
     {
-        guard
-            let legend = legend,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let legend = legend else { return }
         
         if !legend.enabled
         {
@@ -494,7 +488,7 @@ open class LegendRenderer: Renderer
         }
     }
 
-    fileprivate var _formLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _formLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
     
     /// Draws the Legend-form at the given position with the color at the given index.
     @objc open func drawForm(
diff --git a/Source/Charts/Renderers/LineChartRenderer.swift b/Source/Charts/Renderers/LineChartRenderer.swift
index fbb1f7be30..24c5fdf285 100644
--- a/Source/Charts/Renderers/LineChartRenderer.swift
+++ b/Source/Charts/Renderers/LineChartRenderer.swift
@@ -21,7 +21,7 @@ open class LineChartRenderer: LineRadarRenderer
 {
     @objc open weak var dataProvider: LineChartDataProvider?
     
-    @objc public init(dataProvider: LineChartDataProvider?, animator: Animator?, viewPortHandler: ViewPortHandler?)
+    @objc public init(dataProvider: LineChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
@@ -86,10 +86,7 @@ open class LineChartRenderer: LineRadarRenderer
     
     @objc open func drawCubicBezier(context: CGContext, dataSet: ILineChartDataSet)
     {
-        guard
-            let dataProvider = dataProvider,
-            let animator = animator
-            else { return }
+        guard let dataProvider = dataProvider else { return }
         
         let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
         
@@ -183,10 +180,7 @@ open class LineChartRenderer: LineRadarRenderer
     
     @objc open func drawHorizontalBezier(context: CGContext, dataSet: ILineChartDataSet)
     {
-        guard
-            let dataProvider = dataProvider,
-            let animator = animator
-            else { return }
+        guard let dataProvider = dataProvider else { return }
         
         let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
         
@@ -288,15 +282,11 @@ open class LineChartRenderer: LineRadarRenderer
         }
     }
     
-    fileprivate var _lineSegments = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _lineSegments = [CGPoint](repeating: CGPoint(), count: 2)
     
     @objc open func drawLinear(context: CGContext, dataSet: ILineChartDataSet)
     {
-        guard
-            let dataProvider = dataProvider,
-            let animator = animator,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let dataProvider = dataProvider else { return }
         
         let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
         
@@ -463,9 +453,9 @@ open class LineChartRenderer: LineRadarRenderer
     }
     
     /// Generates the path that is used for filled drawing.
-    fileprivate func generateFilledPath(dataSet: ILineChartDataSet, fillMin: CGFloat, bounds: XBounds, matrix: CGAffineTransform) -> CGPath
+    private func generateFilledPath(dataSet: ILineChartDataSet, fillMin: CGFloat, bounds: XBounds, matrix: CGAffineTransform) -> CGPath
     {
-        let phaseY = animator?.phaseY ?? 1.0
+        let phaseY = animator.phaseY
         let isDrawSteppedEnabled = dataSet.mode == .stepped
         let matrix = matrix
         
@@ -509,11 +499,9 @@ open class LineChartRenderer: LineRadarRenderer
     {
         guard
             let dataProvider = dataProvider,
-            let lineData = dataProvider.lineData,
-            let animator = animator,
-            let viewPortHandler = self.viewPortHandler
+            let lineData = dataProvider.lineData
             else { return }
-        
+
         if isDrawingValuesAllowed(dataProvider: dataProvider)
         {
             var dataSets = lineData.dataSets
@@ -601,17 +589,15 @@ open class LineChartRenderer: LineRadarRenderer
         drawCircles(context: context)
     }
     
-    fileprivate func drawCircles(context: CGContext)
+    private func drawCircles(context: CGContext)
     {
         guard
             let dataProvider = dataProvider,
-            let lineData = dataProvider.lineData,
-            let animator = animator,
-            let viewPortHandler = self.viewPortHandler
+            let lineData = dataProvider.lineData
             else { return }
         
         let phaseY = animator.phaseY
-        
+
         let dataSets = lineData.dataSets
         
         var pt = CGPoint()
@@ -714,8 +700,7 @@ open class LineChartRenderer: LineRadarRenderer
     {
         guard
             let dataProvider = dataProvider,
-            let lineData = dataProvider.lineData,
-            let animator = animator
+            let lineData = dataProvider.lineData
             else { return }
         
         let chartXMax = dataProvider.chartXMax
diff --git a/Source/Charts/Renderers/LineRadarRenderer.swift b/Source/Charts/Renderers/LineRadarRenderer.swift
index 8616ec3a01..6b02825053 100644
--- a/Source/Charts/Renderers/LineRadarRenderer.swift
+++ b/Source/Charts/Renderers/LineRadarRenderer.swift
@@ -15,7 +15,7 @@ import CoreGraphics
 @objc(LineRadarChartRenderer)
 open class LineRadarRenderer: LineScatterCandleRadarRenderer
 {
-    public override init(animator: Animator?, viewPortHandler: ViewPortHandler?)
+    public override init(animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
     }
@@ -23,8 +23,6 @@ open class LineRadarRenderer: LineScatterCandleRadarRenderer
     /// Draws the provided path in filled mode with the provided drawable.
     @objc open func drawFilledPath(context: CGContext, path: CGPath, fill: Fill, fillAlpha: CGFloat)
     {
-        guard let viewPortHandler = self.viewPortHandler
-            else { return }
         
         context.saveGState()
         context.beginPath()
diff --git a/Source/Charts/Renderers/LineScatterCandleRadarRenderer.swift b/Source/Charts/Renderers/LineScatterCandleRadarRenderer.swift
index 2d3379960d..05203caf9c 100644
--- a/Source/Charts/Renderers/LineScatterCandleRadarRenderer.swift
+++ b/Source/Charts/Renderers/LineScatterCandleRadarRenderer.swift
@@ -15,7 +15,7 @@ import CoreGraphics
 @objc(LineScatterCandleRadarChartRenderer)
 open class LineScatterCandleRadarRenderer: BarLineScatterCandleBubbleRenderer
 {
-    public override init(animator: Animator?, viewPortHandler: ViewPortHandler?)
+    public override init(animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
     }
@@ -27,9 +27,6 @@ open class LineScatterCandleRadarRenderer: BarLineScatterCandleBubbleRenderer
     /// :param: vertical
     @objc open func drawHighlightLines(context: CGContext, point: CGPoint, set: ILineScatterCandleRadarChartDataSet)
     {
-        guard let
-            viewPortHandler = self.viewPortHandler
-            else { return }
         
         // draw vertical highlight lines
         if set.isVerticalHighlightIndicatorEnabled
diff --git a/Source/Charts/Renderers/PieChartRenderer.swift b/Source/Charts/Renderers/PieChartRenderer.swift
old mode 100755
new mode 100644
index 327cbc8503..a363da290d
--- a/Source/Charts/Renderers/PieChartRenderer.swift
+++ b/Source/Charts/Renderers/PieChartRenderer.swift
@@ -21,7 +21,7 @@ open class PieChartRenderer: DataRenderer
 {
     @objc open weak var chart: PieChartView?
     
-    @objc public init(chart: PieChartView?, animator: Animator?, viewPortHandler: ViewPortHandler?)
+    @objc public init(chart: PieChartView, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
@@ -58,12 +58,12 @@ open class PieChartRenderer: DataRenderer
         let angleMiddle = startAngle + sweepAngle / 2.0
         
         // Other point of the arc
-        let arcEndPointX = center.x + radius * cos((startAngle + sweepAngle) * ChartUtils.Math.FDEG2RAD)
-        let arcEndPointY = center.y + radius * sin((startAngle + sweepAngle) * ChartUtils.Math.FDEG2RAD)
+        let arcEndPointX = center.x + radius * cos((startAngle + sweepAngle).DEG2RAD)
+        let arcEndPointY = center.y + radius * sin((startAngle + sweepAngle).DEG2RAD)
         
         // Middle point on the arc
-        let arcMidPointX = center.x + radius * cos(angleMiddle * ChartUtils.Math.FDEG2RAD)
-        let arcMidPointY = center.y + radius * sin(angleMiddle * ChartUtils.Math.FDEG2RAD)
+        let arcMidPointX = center.x + radius * cos(angleMiddle.DEG2RAD)
+        let arcMidPointY = center.y + radius * sin(angleMiddle.DEG2RAD)
         
         // This is the base of the contained triangle
         let basePointsDistance = sqrt(
@@ -74,7 +74,7 @@ open class PieChartRenderer: DataRenderer
         //   the angle of the contained triangle should stay the same.
         // So let's find out the height of that triangle.
         let containedTriangleHeight = (basePointsDistance / 2.0 *
-            tan((180.0 - angle) / 2.0 * ChartUtils.Math.FDEG2RAD))
+            tan((180.0 - angle).DEG2RAD / 2.0))
         
         // Now we subtract that from the radius
         var spacedRadius = radius - containedTriangleHeight
@@ -92,7 +92,6 @@ open class PieChartRenderer: DataRenderer
     {
         guard
             dataSet.automaticallyDisableSliceSpacing,
-            let viewPortHandler = self.viewPortHandler,
             let data = chart?.data as? PieChartData
             else { return dataSet.sliceSpace }
         
@@ -108,10 +107,7 @@ open class PieChartRenderer: DataRenderer
 
     @objc open func drawDataSet(context: CGContext, dataSet: IPieChartDataSet)
     {
-        guard
-            let chart = chart,
-            let animator = animator
-            else {return }
+        guard let chart = chart else {return }
         
         var angle: CGFloat = 0.0
         let rotationAngle = chart.rotationAngle
@@ -158,7 +154,7 @@ open class PieChartRenderer: DataRenderer
                     
                     let sliceSpaceAngleOuter = visibleAngleCount == 1 ?
                         0.0 :
-                        sliceSpace / (ChartUtils.Math.FDEG2RAD * radius)
+                        sliceSpace / radius.DEG2RAD
                     let startAngleOuter = rotationAngle + (angle + sliceSpaceAngleOuter / 2.0) * CGFloat(phaseY)
                     var sweepAngleOuter = (sliceAngle - sliceSpaceAngleOuter) * CGFloat(phaseY)
                     if sweepAngleOuter < 0.0
@@ -166,15 +162,15 @@ open class PieChartRenderer: DataRenderer
                         sweepAngleOuter = 0.0
                     }
                     
-                    let arcStartPointX = center.x + radius * cos(startAngleOuter * ChartUtils.Math.FDEG2RAD)
-                    let arcStartPointY = center.y + radius * sin(startAngleOuter * ChartUtils.Math.FDEG2RAD)
+                    let arcStartPointX = center.x + radius * cos(startAngleOuter.DEG2RAD)
+                    let arcStartPointY = center.y + radius * sin(startAngleOuter.DEG2RAD)
 
                     let path = CGMutablePath()
                     
                     path.move(to: CGPoint(x: arcStartPointX,
                                           y: arcStartPointY))
                     
-                    path.addRelativeArc(center: center, radius: radius, startAngle: startAngleOuter * ChartUtils.Math.FDEG2RAD, delta: sweepAngleOuter * ChartUtils.Math.FDEG2RAD)
+                    path.addRelativeArc(center: center, radius: radius, startAngle: startAngleOuter.DEG2RAD, delta: sweepAngleOuter.DEG2RAD)
 
                     if drawInnerArc &&
                         (innerRadius > 0.0 || accountForSliceSpacing)
@@ -198,7 +194,7 @@ open class PieChartRenderer: DataRenderer
                         
                         let sliceSpaceAngleInner = visibleAngleCount == 1 || innerRadius == 0.0 ?
                             0.0 :
-                            sliceSpace / (ChartUtils.Math.FDEG2RAD * innerRadius)
+                            sliceSpace / innerRadius.DEG2RAD
                         let startAngleInner = rotationAngle + (angle + sliceSpaceAngleInner / 2.0) * CGFloat(phaseY)
                         var sweepAngleInner = (sliceAngle - sliceSpaceAngleInner) * CGFloat(phaseY)
                         if sweepAngleInner < 0.0
@@ -209,10 +205,10 @@ open class PieChartRenderer: DataRenderer
                         
                         path.addLine(
                             to: CGPoint(
-                                x: center.x + innerRadius * cos(endAngleInner * ChartUtils.Math.FDEG2RAD),
-                                y: center.y + innerRadius * sin(endAngleInner * ChartUtils.Math.FDEG2RAD)))
+                                x: center.x + innerRadius * cos(endAngleInner.DEG2RAD),
+                                y: center.y + innerRadius * sin(endAngleInner.DEG2RAD)))
                         
-                        path.addRelativeArc(center: center, radius: innerRadius, startAngle: endAngleInner * ChartUtils.Math.FDEG2RAD, delta: -sweepAngleInner * ChartUtils.Math.FDEG2RAD)
+                        path.addRelativeArc(center: center, radius: innerRadius, startAngle: endAngleInner.DEG2RAD, delta: -sweepAngleInner.DEG2RAD)
                     }
                     else
                     {
@@ -230,8 +226,8 @@ open class PieChartRenderer: DataRenderer
                                     startAngle: startAngleOuter,
                                     sweepAngle: sweepAngleOuter)
 
-                            let arcEndPointX = center.x + sliceSpaceOffset * cos(angleMiddle * ChartUtils.Math.FDEG2RAD)
-                            let arcEndPointY = center.y + sliceSpaceOffset * sin(angleMiddle * ChartUtils.Math.FDEG2RAD)
+                            let arcEndPointX = center.x + sliceSpaceOffset * cos(angleMiddle.DEG2RAD)
+                            let arcEndPointY = center.y + sliceSpaceOffset * sin(angleMiddle.DEG2RAD)
                             
                             path.addLine(
                                 to: CGPoint(
@@ -262,8 +258,7 @@ open class PieChartRenderer: DataRenderer
     {
         guard
             let chart = chart,
-            let data = chart.data,
-            let animator = animator
+            let data = chart.data
             else { return }
         
         let center = chart.centerCircleBox
@@ -339,7 +334,7 @@ open class PieChartRenderer: DataRenderer
                 
                 let sliceAngle = drawAngles[xIndex]
                 let sliceSpace = getSliceSpace(dataSet: dataSet)
-                let sliceSpaceMiddleAngle = sliceSpace / (ChartUtils.Math.FDEG2RAD * labelRadius)
+                let sliceSpaceMiddleAngle = sliceSpace / labelRadius.DEG2RAD
                 
                 // offset needed to center the drawn text in the slice
                 let angleOffset = (sliceAngle - sliceSpaceMiddleAngle / 2.0) / 2.0
@@ -355,8 +350,8 @@ open class PieChartRenderer: DataRenderer
                     dataSetIndex: i,
                     viewPortHandler: viewPortHandler)
                 
-                let sliceXBase = cos(transformedAngle * ChartUtils.Math.FDEG2RAD)
-                let sliceYBase = sin(transformedAngle * ChartUtils.Math.FDEG2RAD)
+                let sliceXBase = cos(transformedAngle.DEG2RAD)
+                let sliceYBase = sin(transformedAngle.DEG2RAD)
                 
                 let drawXOutside = drawEntryLabels && xValuePosition == .outsideSlice
                 let drawYOutside = drawValues && yValuePosition == .outsideSlice
@@ -388,7 +383,7 @@ open class PieChartRenderer: DataRenderer
                     }
                     
                     let polyline2Length = dataSet.valueLineVariableLength
-                        ? labelRadius * valueLineLength2 * abs(sin(transformedAngle * ChartUtils.Math.FDEG2RAD))
+                        ? labelRadius * valueLineLength2 * abs(sin(transformedAngle.DEG2RAD))
                         : labelRadius * valueLineLength2
                     
                     let pt0 = CGPoint(
@@ -557,12 +552,9 @@ open class PieChartRenderer: DataRenderer
     }
     
     /// draws the hole in the center of the chart and the transparent circle / hole
-    fileprivate func drawHole(context: CGContext)
+    private func drawHole(context: CGContext)
     {
-        guard
-            let chart = chart,
-            let animator = animator
-            else { return }
+        guard let chart = chart else { return }
         
         if chart.drawHoleEnabled
         {
@@ -616,7 +608,7 @@ open class PieChartRenderer: DataRenderer
     }
     
     /// draws the description text in the center of the pie chart makes most sense when center-hole is enabled
-    fileprivate func drawCenterText(context: CGContext)
+    private func drawCenterText(context: CGContext)
     {
         guard
             let chart = chart,
@@ -668,8 +660,7 @@ open class PieChartRenderer: DataRenderer
     {
         guard
             let chart = chart,
-            let data = chart.data,
-            let animator = animator
+            let data = chart.data
             else { return }
         
         context.saveGState()
@@ -737,11 +728,11 @@ open class PieChartRenderer: DataRenderer
 
             let sliceSpaceAngleOuter = visibleAngleCount == 1 ?
                 0.0 :
-                sliceSpace / (ChartUtils.Math.FDEG2RAD * radius)
+                sliceSpace / radius.DEG2RAD
             
             let sliceSpaceAngleShifted = visibleAngleCount == 1 ?
                 0.0 :
-                sliceSpace / (ChartUtils.Math.FDEG2RAD * highlightedRadius)
+                sliceSpace / highlightedRadius.DEG2RAD
             
             let startAngleOuter = rotationAngle + (angle + sliceSpaceAngleOuter / 2.0) * CGFloat(phaseY)
             var sweepAngleOuter = (sliceAngle - sliceSpaceAngleOuter) * CGFloat(phaseY)
@@ -759,11 +750,11 @@ open class PieChartRenderer: DataRenderer
             
             let path = CGMutablePath()
             
-            path.move(to: CGPoint(x: center.x + highlightedRadius * cos(startAngleShifted * ChartUtils.Math.FDEG2RAD),
-                                  y: center.y + highlightedRadius * sin(startAngleShifted * ChartUtils.Math.FDEG2RAD)))
+            path.move(to: CGPoint(x: center.x + highlightedRadius * cos(startAngleShifted.DEG2RAD),
+                                  y: center.y + highlightedRadius * sin(startAngleShifted.DEG2RAD)))
             
-            path.addRelativeArc(center: center, radius: highlightedRadius, startAngle: startAngleShifted * ChartUtils.Math.FDEG2RAD,
-                                delta: sweepAngleShifted * ChartUtils.Math.FDEG2RAD)
+            path.addRelativeArc(center: center, radius: highlightedRadius, startAngle: startAngleShifted.DEG2RAD,
+                                delta: sweepAngleShifted.DEG2RAD)
             
             var sliceSpaceRadius: CGFloat = 0.0
             if accountForSliceSpacing
@@ -772,8 +763,8 @@ open class PieChartRenderer: DataRenderer
                     center: center,
                     radius: radius,
                     angle: sliceAngle * CGFloat(phaseY),
-                    arcStartPointX: center.x + radius * cos(startAngleOuter * ChartUtils.Math.FDEG2RAD),
-                    arcStartPointY: center.y + radius * sin(startAngleOuter * ChartUtils.Math.FDEG2RAD),
+                    arcStartPointX: center.x + radius * cos(startAngleOuter.DEG2RAD),
+                    arcStartPointY: center.y + radius * sin(startAngleOuter.DEG2RAD),
                     startAngle: startAngleOuter,
                     sweepAngle: sweepAngleOuter)
             }
@@ -793,7 +784,7 @@ open class PieChartRenderer: DataRenderer
                 
                 let sliceSpaceAngleInner = visibleAngleCount == 1 || innerRadius == 0.0 ?
                     0.0 :
-                    sliceSpace / (ChartUtils.Math.FDEG2RAD * innerRadius)
+                    sliceSpace / innerRadius.DEG2RAD
                 let startAngleInner = rotationAngle + (angle + sliceSpaceAngleInner / 2.0) * CGFloat(phaseY)
                 var sweepAngleInner = (sliceAngle - sliceSpaceAngleInner) * CGFloat(phaseY)
                 if sweepAngleInner < 0.0
@@ -804,12 +795,12 @@ open class PieChartRenderer: DataRenderer
                 
                 path.addLine(
                     to: CGPoint(
-                        x: center.x + innerRadius * cos(endAngleInner * ChartUtils.Math.FDEG2RAD),
-                        y: center.y + innerRadius * sin(endAngleInner * ChartUtils.Math.FDEG2RAD)))
+                        x: center.x + innerRadius * cos(endAngleInner.DEG2RAD),
+                        y: center.y + innerRadius * sin(endAngleInner.DEG2RAD)))
                 
                 path.addRelativeArc(center: center, radius: innerRadius,
-                                    startAngle: endAngleInner * ChartUtils.Math.FDEG2RAD,
-                                    delta: -sweepAngleInner * ChartUtils.Math.FDEG2RAD)
+                                    startAngle: endAngleInner.DEG2RAD,
+                                    delta: -sweepAngleInner.DEG2RAD)
             }
             else
             {
@@ -817,8 +808,8 @@ open class PieChartRenderer: DataRenderer
                 {
                     let angleMiddle = startAngleOuter + sweepAngleOuter / 2.0
                     
-                    let arcEndPointX = center.x + sliceSpaceRadius * cos(angleMiddle * ChartUtils.Math.FDEG2RAD)
-                    let arcEndPointY = center.y + sliceSpaceRadius * sin(angleMiddle * ChartUtils.Math.FDEG2RAD)
+                    let arcEndPointX = center.x + sliceSpaceRadius * cos(angleMiddle.DEG2RAD)
+                    let arcEndPointY = center.y + sliceSpaceRadius * sin(angleMiddle.DEG2RAD)
                     
                     path.addLine(
                         to: CGPoint(
diff --git a/Source/Charts/Renderers/RadarChartRenderer.swift b/Source/Charts/Renderers/RadarChartRenderer.swift
index 57068555f7..ab4890f646 100644
--- a/Source/Charts/Renderers/RadarChartRenderer.swift
+++ b/Source/Charts/Renderers/RadarChartRenderer.swift
@@ -21,7 +21,7 @@ open class RadarChartRenderer: LineRadarRenderer
 {
     @objc open weak var chart: RadarChartView?
 
-    @objc public init(chart: RadarChartView?, animator: Animator?, viewPortHandler: ViewPortHandler?)
+    @objc public init(chart: RadarChartView, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
@@ -53,12 +53,9 @@ open class RadarChartRenderer: LineRadarRenderer
     /// - parameter context:
     /// - parameter dataSet:
     /// - parameter mostEntries: the entry count of the dataset with the most entries
-    @objc internal func drawDataSet(context: CGContext, dataSet: IRadarChartDataSet, mostEntries: Int)
+    internal func drawDataSet(context: CGContext, dataSet: IRadarChartDataSet, mostEntries: Int)
     {
-        guard let
-            chart = chart,
-            let animator = animator
-            else { return }
+        guard let chart = chart else { return }
         
         context.saveGState()
         
@@ -141,8 +138,7 @@ open class RadarChartRenderer: LineRadarRenderer
     {
         guard
             let chart = chart,
-            let data = chart.data,
-            let animator = animator
+            let data = chart.data
             else { return }
         
         let phaseX = animator.phaseX
@@ -222,7 +218,7 @@ open class RadarChartRenderer: LineRadarRenderer
         drawWeb(context: context)
     }
     
-    fileprivate var _webLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _webLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
     
     @objc open func drawWeb(context: CGContext)
     {
@@ -293,14 +289,13 @@ open class RadarChartRenderer: LineRadarRenderer
         context.restoreGState()
     }
     
-    fileprivate var _highlightPointBuffer = CGPoint()
+    private var _highlightPointBuffer = CGPoint()
 
     open override func drawHighlighted(context: CGContext, indices: [Highlight])
     {
         guard
             let chart = chart,
-            let radarData = chart.data as? RadarChartData,
-            let animator = animator
+            let radarData = chart.data as? RadarChartData
             else { return }
         
         context.saveGState()
@@ -380,7 +375,7 @@ open class RadarChartRenderer: LineRadarRenderer
         context.restoreGState()
     }
     
-    @objc internal func drawHighlightCircle(
+    internal func drawHighlightCircle(
         context: CGContext,
         atPoint point: CGPoint,
         innerRadius: CGFloat,
diff --git a/Source/Charts/Renderers/Renderer.swift b/Source/Charts/Renderers/Renderer.swift
index 86727524b3..5c929f28e0 100644
--- a/Source/Charts/Renderers/Renderer.swift
+++ b/Source/Charts/Renderers/Renderer.swift
@@ -16,17 +16,11 @@ import CoreGraphics
 open class Renderer: NSObject
 {
     /// the component that handles the drawing area of the chart and it's offsets
-    @objc open var viewPortHandler: ViewPortHandler?
-    
-    public override init()
-    {
-        super.init()
-    }
-    
-    @objc public init(viewPortHandler: ViewPortHandler?)
+    @objc open let viewPortHandler: ViewPortHandler
+
+    @objc public init(viewPortHandler: ViewPortHandler)
     {
-        super.init()
         self.viewPortHandler = viewPortHandler
+        super.init()
     }
 }
-        
diff --git a/Source/Charts/Renderers/ScatterChartRenderer.swift b/Source/Charts/Renderers/ScatterChartRenderer.swift
index c9148caa7b..010ca16791 100644
--- a/Source/Charts/Renderers/ScatterChartRenderer.swift
+++ b/Source/Charts/Renderers/ScatterChartRenderer.swift
@@ -21,7 +21,7 @@ open class ScatterChartRenderer: LineScatterCandleRadarRenderer
 {
     @objc open weak var dataProvider: ScatterChartDataProvider?
     
-    @objc public init(dataProvider: ScatterChartDataProvider?, animator: Animator?, viewPortHandler: ViewPortHandler?)
+    @objc public init(dataProvider: ScatterChartDataProvider, animator: Animator, viewPortHandler: ViewPortHandler)
     {
         super.init(animator: animator, viewPortHandler: viewPortHandler)
         
@@ -48,15 +48,11 @@ open class ScatterChartRenderer: LineScatterCandleRadarRenderer
         }
     }
     
-    fileprivate var _lineSegments = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _lineSegments = [CGPoint](repeating: CGPoint(), count: 2)
     
     @objc open func drawDataSet(context: CGContext, dataSet: IScatterChartDataSet)
     {
-        guard
-            let dataProvider = dataProvider,
-            let animator = animator,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let dataProvider = dataProvider else { return }
         
         let trans = dataProvider.getTransformer(forAxis: dataSet.axisDependency)
         
@@ -106,9 +102,7 @@ open class ScatterChartRenderer: LineScatterCandleRadarRenderer
     {
         guard
             let dataProvider = dataProvider,
-            let scatterData = dataProvider.scatterData,
-            let animator = animator,
-            let viewPortHandler = self.viewPortHandler
+            let scatterData = dataProvider.scatterData
             else { return }
         
         // if values are drawn
@@ -204,8 +198,7 @@ open class ScatterChartRenderer: LineScatterCandleRadarRenderer
     {
         guard
             let dataProvider = dataProvider,
-            let scatterData = dataProvider.scatterData,
-            let animator = animator
+            let scatterData = dataProvider.scatterData
             else { return }
         
         context.saveGState()
diff --git a/Source/Charts/Renderers/XAxisRenderer.swift b/Source/Charts/Renderers/XAxisRenderer.swift
index bb75d25450..534e606dcf 100644
--- a/Source/Charts/Renderers/XAxisRenderer.swift
+++ b/Source/Charts/Renderers/XAxisRenderer.swift
@@ -19,17 +19,13 @@ import CoreGraphics
 @objc(ChartXAxisRenderer)
 open class XAxisRenderer: AxisRendererBase
 {
-    @objc public init(viewPortHandler: ViewPortHandler?, xAxis: XAxis?, transformer: Transformer?)
+    @objc public init(viewPortHandler: ViewPortHandler, xAxis: XAxis?, transformer: Transformer?)
     {
         super.init(viewPortHandler: viewPortHandler, transformer: transformer, axis: xAxis)
     }
     
     open override func computeAxis(min: Double, max: Double, inverted: Bool)
     {
-        guard let
-            viewPortHandler = self.viewPortHandler
-            else { return }
-        
         var min = min, max = max
         
         if let transformer = self.transformer
@@ -87,10 +83,7 @@ open class XAxisRenderer: AxisRendererBase
     
     open override func renderAxisLabels(context: CGContext)
     {
-        guard let
-            xAxis = self.axis as? XAxis,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let xAxis = self.axis as? XAxis else { return }
         
         if !xAxis.isEnabled || !xAxis.isDrawLabelsEnabled
         {
@@ -122,14 +115,11 @@ open class XAxisRenderer: AxisRendererBase
         }
     }
     
-    fileprivate var _axisLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _axisLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
     
     open override func renderAxisLine(context: CGContext)
     {
-        guard
-            let xAxis = self.axis as? XAxis,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let xAxis = self.axis as? XAxis else { return }
         
         if !xAxis.isEnabled || !xAxis.isDrawAxisLineEnabled
         {
@@ -179,7 +169,6 @@ open class XAxisRenderer: AxisRendererBase
     {
         guard
             let xAxis = self.axis as? XAxis,
-            let viewPortHandler = self.viewPortHandler,
             let transformer = self.transformer
             else { return }
         
@@ -193,7 +182,7 @@ open class XAxisRenderer: AxisRendererBase
         let labelAttrs: [NSAttributedStringKey : Any] = [NSAttributedStringKey.font: xAxis.labelFont,
             NSAttributedStringKey.foregroundColor: xAxis.labelTextColor,
             NSAttributedStringKey.paragraphStyle: paraStyle]
-        let labelRotationAngleRadians = xAxis.labelRotationAngle * ChartUtils.Math.FDEG2RAD
+        let labelRotationAngleRadians = xAxis.labelRotationAngle.DEG2RAD
         
         let centeringEnabled = xAxis.isCenterAxisLabelsEnabled
 
@@ -330,7 +319,7 @@ open class XAxisRenderer: AxisRendererBase
     
     @objc open var gridClippingRect: CGRect
     {
-        var contentRect = viewPortHandler?.contentRect ?? CGRect.zero
+        var contentRect = viewPortHandler.contentRect
         let dx = self.axis?.gridLineWidth ?? 0.0
         contentRect.origin.x -= dx / 2.0
         contentRect.size.width += dx
@@ -339,10 +328,6 @@ open class XAxisRenderer: AxisRendererBase
     
     @objc open func drawGridLine(context: CGContext, x: CGFloat, y: CGFloat)
     {
-        guard
-            let viewPortHandler = self.viewPortHandler
-            else { return }
-        
         if x >= viewPortHandler.offsetLeft
             && x <= viewPortHandler.chartWidth
         {
@@ -357,7 +342,6 @@ open class XAxisRenderer: AxisRendererBase
     {
         guard
             let xAxis = self.axis as? XAxis,
-            let viewPortHandler = self.viewPortHandler,
             let transformer = self.transformer
             else { return }
         
@@ -400,9 +384,6 @@ open class XAxisRenderer: AxisRendererBase
     
     @objc open func renderLimitLineLine(context: CGContext, limitLine: ChartLimitLine, position: CGPoint)
     {
-        guard
-            let viewPortHandler = self.viewPortHandler
-            else { return }
         
         context.beginPath()
         context.move(to: CGPoint(x: position.x, y: viewPortHandler.contentTop))
@@ -424,9 +405,6 @@ open class XAxisRenderer: AxisRendererBase
     
     @objc open func renderLimitLineLabel(context: CGContext, limitLine: ChartLimitLine, position: CGPoint, yOffset: CGFloat)
     {
-        guard
-            let viewPortHandler = self.viewPortHandler
-            else { return }
         
         let label = limitLine.label
         
diff --git a/Source/Charts/Renderers/XAxisRendererHorizontalBarChart.swift b/Source/Charts/Renderers/XAxisRendererHorizontalBarChart.swift
index 97f0c56029..d2e0c29306 100644
--- a/Source/Charts/Renderers/XAxisRendererHorizontalBarChart.swift
+++ b/Source/Charts/Renderers/XAxisRendererHorizontalBarChart.swift
@@ -18,9 +18,9 @@ import CoreGraphics
 
 open class XAxisRendererHorizontalBarChart: XAxisRenderer
 {
-    @objc internal var chart: BarChartView?
+    internal weak var chart: BarChartView?
     
-    @objc public init(viewPortHandler: ViewPortHandler?, xAxis: XAxis?, transformer: Transformer?, chart: BarChartView?)
+    @objc public init(viewPortHandler: ViewPortHandler, xAxis: XAxis?, transformer: Transformer?, chart: BarChartView)
     {
         super.init(viewPortHandler: viewPortHandler, xAxis: xAxis, transformer: transformer)
         
@@ -29,10 +29,6 @@ open class XAxisRendererHorizontalBarChart: XAxisRenderer
     
     open override func computeAxis(min: Double, max: Double, inverted: Bool)
     {
-        guard let
-            viewPortHandler = self.viewPortHandler
-            else { return }
-        
         var min = min, max = max
         
         if let transformer = self.transformer
@@ -83,8 +79,7 @@ open class XAxisRendererHorizontalBarChart: XAxisRenderer
     open override func renderAxisLabels(context: CGContext)
     {
         guard
-            let xAxis = self.axis as? XAxis,
-            let viewPortHandler = self.viewPortHandler
+            let xAxis = self.axis as? XAxis
             else { return }
         
         if !xAxis.isEnabled || !xAxis.isDrawLabelsEnabled || chart?.data === nil
@@ -122,13 +117,12 @@ open class XAxisRendererHorizontalBarChart: XAxisRenderer
     {
         guard
             let xAxis = self.axis as? XAxis,
-            let transformer = self.transformer,
-            let viewPortHandler = self.viewPortHandler
+            let transformer = self.transformer
             else { return }
         
         let labelFont = xAxis.labelFont
         let labelTextColor = xAxis.labelTextColor
-        let labelRotationAngleRadians = xAxis.labelRotationAngle * ChartUtils.Math.FDEG2RAD
+        let labelRotationAngleRadians = xAxis.labelRotationAngle.DEG2RAD
         
         let centeringEnabled = xAxis.isCenterAxisLabelsEnabled
         
@@ -189,21 +183,17 @@ open class XAxisRendererHorizontalBarChart: XAxisRenderer
     
     open override var gridClippingRect: CGRect
     {
-        var contentRect = viewPortHandler?.contentRect ?? CGRect.zero
+        var contentRect = viewPortHandler.contentRect
         let dy = self.axis?.gridLineWidth ?? 0.0
         contentRect.origin.y -= dy / 2.0
         contentRect.size.height += dy
         return contentRect
     }
     
-    fileprivate var _gridLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _gridLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
     
     open override func drawGridLine(context: CGContext, x: CGFloat, y: CGFloat)
     {
-        guard
-            let viewPortHandler = self.viewPortHandler
-            else { return }
-        
         if viewPortHandler.isInBoundsY(y)
         {
             context.beginPath()
@@ -215,10 +205,7 @@ open class XAxisRendererHorizontalBarChart: XAxisRenderer
     
     open override func renderAxisLine(context: CGContext)
     {
-        guard
-            let xAxis = self.axis as? XAxis,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let xAxis = self.axis as? XAxis else { return }
         
         if !xAxis.isEnabled || !xAxis.isDrawAxisLineEnabled
         {
@@ -265,7 +252,6 @@ open class XAxisRendererHorizontalBarChart: XAxisRenderer
     {
         guard
             let xAxis = self.axis as? XAxis,
-            let viewPortHandler = self.viewPortHandler,
             let transformer = self.transformer
             else { return }
         
diff --git a/Source/Charts/Renderers/XAxisRendererRadarChart.swift b/Source/Charts/Renderers/XAxisRendererRadarChart.swift
index 2f78ce2303..ab57149cce 100644
--- a/Source/Charts/Renderers/XAxisRendererRadarChart.swift
+++ b/Source/Charts/Renderers/XAxisRendererRadarChart.swift
@@ -20,7 +20,7 @@ open class XAxisRendererRadarChart: XAxisRenderer
 {
     @objc open weak var chart: RadarChartView?
     
-    @objc public init(viewPortHandler: ViewPortHandler?, xAxis: XAxis?, chart: RadarChartView?)
+    @objc public init(viewPortHandler: ViewPortHandler, xAxis: XAxis?, chart: RadarChartView)
     {
         super.init(viewPortHandler: viewPortHandler, xAxis: xAxis, transformer: nil)
         
@@ -41,7 +41,7 @@ open class XAxisRendererRadarChart: XAxisRenderer
         
         let labelFont = xAxis.labelFont
         let labelTextColor = xAxis.labelTextColor
-        let labelRotationAngleRadians = xAxis.labelRotationAngle * ChartUtils.Math.FDEG2RAD
+        let labelRotationAngleRadians = xAxis.labelRotationAngle.RAD2DEG
         let drawLabelAnchor = CGPoint(x: 0.5, y: 0.25)
         
         let sliceangle = chart.sliceAngle
diff --git a/Source/Charts/Renderers/YAxisRenderer.swift b/Source/Charts/Renderers/YAxisRenderer.swift
index 511400a09d..e5b0802575 100644
--- a/Source/Charts/Renderers/YAxisRenderer.swift
+++ b/Source/Charts/Renderers/YAxisRenderer.swift
@@ -19,7 +19,7 @@ import CoreGraphics
 @objc(ChartYAxisRenderer)
 open class YAxisRenderer: AxisRendererBase
 {
-    @objc public init(viewPortHandler: ViewPortHandler?, yAxis: YAxis?, transformer: Transformer?)
+    @objc public init(viewPortHandler: ViewPortHandler, yAxis: YAxis?, transformer: Transformer?)
     {
         super.init(viewPortHandler: viewPortHandler, transformer: transformer, axis: yAxis)
     }
@@ -27,10 +27,7 @@ open class YAxisRenderer: AxisRendererBase
     /// draws the y-axis labels to the screen
     open override func renderAxisLabels(context: CGContext)
     {
-        guard
-            let yAxis = self.axis as? YAxis,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let yAxis = self.axis as? YAxis else { return }
         
         if !yAxis.isEnabled || !yAxis.isDrawLabelsEnabled
         {
@@ -85,10 +82,7 @@ open class YAxisRenderer: AxisRendererBase
     
     open override func renderAxisLine(context: CGContext)
     {
-        guard
-            let yAxis = self.axis as? YAxis,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let yAxis = self.axis as? YAxis else { return }
         
         if !yAxis.isEnabled || !yAxis.drawAxisLineEnabled
         {
@@ -127,7 +121,7 @@ open class YAxisRenderer: AxisRendererBase
     }
     
     /// draws the y-labels on the specified x-position
-    @objc internal func drawYLabels(
+    internal func drawYLabels(
         context: CGContext,
         fixedPosition: CGFloat,
         positions: [CGPoint],
@@ -207,7 +201,7 @@ open class YAxisRenderer: AxisRendererBase
     
     @objc open var gridClippingRect: CGRect
     {
-        var contentRect = viewPortHandler?.contentRect ?? CGRect.zero
+        var contentRect = viewPortHandler.contentRect
         let dy = self.axis?.gridLineWidth ?? 0.0
         contentRect.origin.y -= dy / 2.0
         contentRect.size.height += dy
@@ -218,10 +212,6 @@ open class YAxisRenderer: AxisRendererBase
         context: CGContext,
         position: CGPoint)
     {
-        guard
-            let viewPortHandler = self.viewPortHandler
-            else { return }
-        
         context.beginPath()
         context.move(to: CGPoint(x: viewPortHandler.contentLeft, y: position.y))
         context.addLine(to: CGPoint(x: viewPortHandler.contentRight, y: position.y))
@@ -255,7 +245,6 @@ open class YAxisRenderer: AxisRendererBase
     {
         guard
             let yAxis = self.axis as? YAxis,
-            let viewPortHandler = self.viewPortHandler,
             let transformer = self.transformer,
             let zeroLineColor = yAxis.zeroLineColor
             else { return }
@@ -291,7 +280,6 @@ open class YAxisRenderer: AxisRendererBase
     {
         guard
             let yAxis = self.axis as? YAxis,
-            let viewPortHandler = self.viewPortHandler,
             let transformer = self.transformer
             else { return }
         
diff --git a/Source/Charts/Renderers/YAxisRendererHorizontalBarChart.swift b/Source/Charts/Renderers/YAxisRendererHorizontalBarChart.swift
index 15c1a1539f..ba7c51f17f 100644
--- a/Source/Charts/Renderers/YAxisRendererHorizontalBarChart.swift
+++ b/Source/Charts/Renderers/YAxisRendererHorizontalBarChart.swift
@@ -18,7 +18,7 @@ import CoreGraphics
 
 open class YAxisRendererHorizontalBarChart: YAxisRenderer
 {
-    public override init(viewPortHandler: ViewPortHandler?, yAxis: YAxis?, transformer: Transformer?)
+    public override init(viewPortHandler: ViewPortHandler, yAxis: YAxis?, transformer: Transformer?)
     {
         super.init(viewPortHandler: viewPortHandler, yAxis: yAxis, transformer: transformer)
     }
@@ -26,10 +26,7 @@ open class YAxisRendererHorizontalBarChart: YAxisRenderer
     /// Computes the axis values.
     open override func computeAxis(min: Double, max: Double, inverted: Bool)
     {
-        guard
-            let viewPortHandler = self.viewPortHandler,
-            let transformer = self.transformer
-            else { return }
+        guard let transformer = self.transformer else { return }
         
         var min = min, max = max
         
@@ -57,10 +54,7 @@ open class YAxisRendererHorizontalBarChart: YAxisRenderer
     /// draws the y-axis labels to the screen
     open override func renderAxisLabels(context: CGContext)
     {
-        guard
-            let yAxis = axis as? YAxis,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let yAxis = axis as? YAxis else { return }
         
         if !yAxis.isEnabled || !yAxis.isDrawLabelsEnabled
         {
@@ -111,10 +105,7 @@ open class YAxisRendererHorizontalBarChart: YAxisRenderer
     
     open override func renderAxisLine(context: CGContext)
     {
-        guard
-            let yAxis = axis as? YAxis,
-            let viewPortHandler = self.viewPortHandler
-            else { return }
+        guard let yAxis = axis as? YAxis else { return }
         
         if !yAxis.isEnabled || !yAxis.drawAxisLineEnabled
         {
@@ -183,7 +174,7 @@ open class YAxisRendererHorizontalBarChart: YAxisRenderer
     
     open override var gridClippingRect: CGRect
     {
-        var contentRect = viewPortHandler?.contentRect ?? CGRect.zero
+        var contentRect = viewPortHandler.contentRect
         let dx = self.axis?.gridLineWidth ?? 0.0
         contentRect.origin.x -= dx / 2.0
         contentRect.size.width += dx
@@ -194,10 +185,6 @@ open class YAxisRendererHorizontalBarChart: YAxisRenderer
         context: CGContext,
         position: CGPoint)
     {
-        guard
-            let viewPortHandler = self.viewPortHandler
-            else { return }
-        
         context.beginPath()
         context.move(to: CGPoint(x: position.x, y: viewPortHandler.contentTop))
         context.addLine(to: CGPoint(x: position.x, y: viewPortHandler.contentBottom))
@@ -231,7 +218,6 @@ open class YAxisRendererHorizontalBarChart: YAxisRenderer
     {
         guard
             let yAxis = self.axis as? YAxis,
-            let viewPortHandler = self.viewPortHandler,
             let transformer = self.transformer,
             let zeroLineColor = yAxis.zeroLineColor
             else { return }
@@ -263,13 +249,12 @@ open class YAxisRendererHorizontalBarChart: YAxisRenderer
         context.drawPath(using: CGPathDrawingMode.stroke)
     }
     
-    fileprivate var _limitLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
+    private var _limitLineSegmentsBuffer = [CGPoint](repeating: CGPoint(), count: 2)
     
     open override func renderLimitLines(context: CGContext)
     {
         guard
             let yAxis = axis as? YAxis,
-            let viewPortHandler = self.viewPortHandler,
             let transformer = self.transformer
             else { return }
         
diff --git a/Source/Charts/Renderers/YAxisRendererRadarChart.swift b/Source/Charts/Renderers/YAxisRendererRadarChart.swift
index cab45f7125..b23b987556 100644
--- a/Source/Charts/Renderers/YAxisRendererRadarChart.swift
+++ b/Source/Charts/Renderers/YAxisRendererRadarChart.swift
@@ -18,9 +18,9 @@ import CoreGraphics
 
 open class YAxisRendererRadarChart: YAxisRenderer
 {
-    fileprivate weak var chart: RadarChartView?
+    private weak var chart: RadarChartView?
     
-    @objc public init(viewPortHandler: ViewPortHandler?, yAxis: YAxis?, chart: RadarChartView?)
+    @objc public init(viewPortHandler: ViewPortHandler, yAxis: YAxis?, chart: RadarChartView)
     {
         super.init(viewPortHandler: viewPortHandler, yAxis: yAxis, transformer: nil)
         
diff --git a/Source/Charts/Utils/ChartUtils.swift b/Source/Charts/Utils/ChartUtils.swift
old mode 100755
new mode 100644
index a1c56ab477..d5b441e164
--- a/Source/Charts/Utils/ChartUtils.swift
+++ b/Source/Charts/Utils/ChartUtils.swift
@@ -16,9 +16,26 @@ import CoreGraphics
     import UIKit
 #endif
 
+extension FloatingPoint {
+    var DEG2RAD: Self {
+        return self * .pi / 180
+    }
+
+    var RAD2DEG: Self {
+        return self * 180 / .pi
+    }
+
+    /// - returns: An angle between 0.0 < 360.0 (not less than zero, less than 360)
+    /// NOTE: Value must be in degrees
+    var normalizedAngle: Self {
+        let angle = truncatingRemainder(dividingBy: 360)
+        return (sign == .minus) ? angle + 360 : angle
+    }
+}
+
 extension CGSize {
     func rotatedBy(degrees: CGFloat) -> CGSize {
-        let radians = ChartUtils.Math.FDEG2RAD * degrees
+        let radians = degrees.DEG2RAD
         return rotatedBy(radians: radians)
     }
 
@@ -32,16 +49,8 @@ extension CGSize {
 
 open class ChartUtils
 {
-    fileprivate static var _defaultValueFormatter: IValueFormatter = ChartUtils.generateDefaultValueFormatter()
-    
-    internal struct Math
-    {
-        internal static let FDEG2RAD = CGFloat(Double.pi / 180.0)
-        internal static let FRAD2DEG = CGFloat(180.0 / Double.pi)
-        internal static let DEG2RAD = Double.pi / 180.0
-        internal static let RAD2DEG = 180.0 / Double.pi
-    }
-    
+    private static var _defaultValueFormatter: IValueFormatter = ChartUtils.generateDefaultValueFormatter()
+
     internal class func roundToNextSignificant(number: Double) -> Double
     {
         if number.isInfinite || number.isNaN || number == 0
@@ -89,8 +98,8 @@ open class ChartUtils
     internal class func getPosition(center: CGPoint, dist: CGFloat, angle: CGFloat) -> CGPoint
     {
         return CGPoint(
-            x: center.x + dist * cos(angle * Math.FDEG2RAD),
-            y: center.y + dist * sin(angle * Math.FDEG2RAD)
+            x: center.x + dist * cos(angle.DEG2RAD),
+            y: center.y + dist * sin(angle.DEG2RAD)
         )
     }
     
@@ -262,21 +271,8 @@ open class ChartUtils
         let rect = text.boundingRect(with: constrainedToSize, options: .usesLineFragmentOrigin, attributes: attributes, context: nil)
         drawMultilineText(context: context, text: text, knownTextSize: rect.size, point: point, attributes: attributes, constrainedToSize: constrainedToSize, anchor: anchor, angleRadians: angleRadians)
     }
-    
-    /// - returns: An angle between 0.0 < 360.0 (not less than zero, less than 360)
-    internal class func normalizedAngleFromAngle(_ angle: CGFloat) -> CGFloat
-    {
-        var angle = angle
-        
-        while (angle < 0.0)
-        {
-            angle += 360.0
-        }
-        
-        return angle.truncatingRemainder(dividingBy: 360.0)
-    }
-    
-    fileprivate class func generateDefaultValueFormatter() -> IValueFormatter
+
+    private class func generateDefaultValueFormatter() -> IValueFormatter
     {
         let formatter = DefaultValueFormatter(decimals: 1)
         return formatter
diff --git a/Source/Charts/Utils/Fill.swift b/Source/Charts/Utils/Fill.swift
index 58c6fe693e..1294b3efc0 100644
--- a/Source/Charts/Utils/Fill.swift
+++ b/Source/Charts/Utils/Fill.swift
@@ -27,16 +27,16 @@ public enum FillType: Int
 @objc(ChartFill)
 open class Fill: NSObject
 {
-    fileprivate var _type: FillType = FillType.empty
-    fileprivate var _color: CGColor?
-    fileprivate var _gradient: CGGradient?
-    fileprivate var _gradientAngle: CGFloat = 0.0
-    fileprivate var _gradientStartOffsetPercent: CGPoint = CGPoint()
-    fileprivate var _gradientStartRadiusPercent: CGFloat = 0.0
-    fileprivate var _gradientEndOffsetPercent: CGPoint = CGPoint()
-    fileprivate var _gradientEndRadiusPercent: CGFloat = 0.0
-    fileprivate var _image: CGImage?
-    fileprivate var _layer: CGLayer?
+    private var _type: FillType = FillType.empty
+    private var _color: CGColor?
+    private var _gradient: CGGradient?
+    private var _gradientAngle: CGFloat = 0.0
+    private var _gradientStartOffsetPercent: CGPoint = CGPoint()
+    private var _gradientStartRadiusPercent: CGFloat = 0.0
+    private var _gradientEndOffsetPercent: CGPoint = CGPoint()
+    private var _gradientEndRadiusPercent: CGFloat = 0.0
+    private var _image: CGImage?
+    private var _layer: CGLayer?
     
     // MARK: Properties
     
@@ -273,7 +273,7 @@ open class Fill: NSObject
             
         case .linearGradient:
             
-            let radians = ChartUtils.Math.FDEG2RAD * (360.0 - _gradientAngle)
+            let radians = (360.0 - _gradientAngle).DEG2RAD
             let centerPoint = CGPoint(x: rect.midX, y: rect.midY)
             let xAngleDelta = cos(radians) * rect.width / 2.0
             let yAngleDelta = sin(radians) * rect.height / 2.0
diff --git a/Source/Charts/Utils/Transformer.swift b/Source/Charts/Utils/Transformer.swift
index 71110ec722..ca99fb2360 100644
--- a/Source/Charts/Utils/Transformer.swift
+++ b/Source/Charts/Utils/Transformer.swift
@@ -17,12 +17,12 @@ import CoreGraphics
 open class Transformer: NSObject
 {
     /// matrix to map the values to the screen pixels
-    @objc internal var _matrixValueToPx = CGAffineTransform.identity
+    internal var _matrixValueToPx = CGAffineTransform.identity
 
     /// matrix for handling the different offsets of the chart
-    @objc internal var _matrixOffset = CGAffineTransform.identity
+    internal var _matrixOffset = CGAffineTransform.identity
 
-    @objc internal var _viewPortHandler: ViewPortHandler
+    internal var _viewPortHandler: ViewPortHandler
 
     @objc public init(viewPortHandler: ViewPortHandler)
     {
diff --git a/Source/Charts/Utils/ViewPortHandler.swift b/Source/Charts/Utils/ViewPortHandler.swift
index 6e184e0b3f..db45d61cb3 100755
--- a/Source/Charts/Utils/ViewPortHandler.swift
+++ b/Source/Charts/Utils/ViewPortHandler.swift
@@ -17,47 +17,43 @@ import CoreGraphics
 open class ViewPortHandler: NSObject
 {
     /// matrix used for touch events
-    fileprivate var _touchMatrix = CGAffineTransform.identity
+    private var _touchMatrix = CGAffineTransform.identity
     
     /// this rectangle defines the area in which graph values can be drawn
-    fileprivate var _contentRect = CGRect()
+    private var _contentRect = CGRect()
     
-    fileprivate var _chartWidth = CGFloat(0.0)
-    fileprivate var _chartHeight = CGFloat(0.0)
+    private var _chartWidth = CGFloat(0.0)
+    private var _chartHeight = CGFloat(0.0)
     
     /// minimum scale value on the y-axis
-    fileprivate var _minScaleY = CGFloat(1.0)
+    private var _minScaleY = CGFloat(1.0)
     
     /// maximum scale value on the y-axis
-    fileprivate var _maxScaleY = CGFloat.greatestFiniteMagnitude
+    private var _maxScaleY = CGFloat.greatestFiniteMagnitude
     
     /// minimum scale value on the x-axis
-    fileprivate var _minScaleX = CGFloat(1.0)
+    private var _minScaleX = CGFloat(1.0)
     
     /// maximum scale value on the x-axis
-    fileprivate var _maxScaleX = CGFloat.greatestFiniteMagnitude
+    private var _maxScaleX = CGFloat.greatestFiniteMagnitude
     
     /// contains the current scale factor of the x-axis
-    fileprivate var _scaleX = CGFloat(1.0)
+    private var _scaleX = CGFloat(1.0)
     
     /// contains the current scale factor of the y-axis
-    fileprivate var _scaleY = CGFloat(1.0)
+    private var _scaleY = CGFloat(1.0)
     
     /// current translation (drag distance) on the x-axis
-    fileprivate var _transX = CGFloat(0.0)
+    private var _transX = CGFloat(0.0)
     
     /// current translation (drag distance) on the y-axis
-    fileprivate var _transY = CGFloat(0.0)
+    private var _transY = CGFloat(0.0)
     
     /// offset that allows the chart to be dragged over its bounds on the x-axis
-    fileprivate var _transOffsetX = CGFloat(0.0)
+    private var _transOffsetX = CGFloat(0.0)
     
     /// offset that allows the chart to be dragged over its bounds on the x-axis
-    fileprivate var _transOffsetY = CGFloat(0.0)
-    
-    public override init()
-    {
-    }
+    private var _transOffsetY = CGFloat(0.0)
     
     /// Constructor - don't forget calling setChartDimens(...)
     @objc public init(width: CGFloat, height: CGFloat)
@@ -255,12 +251,11 @@ open class ViewPortHandler: NSObject
         let translateY = pt.y - offsetTop
         
         let matrix = _touchMatrix.concatenating(CGAffineTransform(translationX: -translateX, y: -translateY))
-        
-        let _ = refresh(newMatrix: matrix, chart: chart, invalidate: true)
+        refresh(newMatrix: matrix, chart: chart, invalidate: true)
     }
     
     /// call this method to refresh the graph with a given matrix
-    @objc open func refresh(newMatrix: CGAffineTransform, chart: ChartViewBase, invalidate: Bool) -> CGAffineTransform
+    @objc @discardableResult open func refresh(newMatrix: CGAffineTransform, chart: ChartViewBase, invalidate: Bool) -> CGAffineTransform
     {
         _touchMatrix = newMatrix
         
@@ -273,7 +268,7 @@ open class ViewPortHandler: NSObject
     }
     
     /// limits the maximum scale and X translation of the given matrix
-    fileprivate func limitTransAndScale(matrix: inout CGAffineTransform, content: CGRect?)
+    private func limitTransAndScale(matrix: inout CGAffineTransform, content: CGRect?)
     {
         // min scale-x is 1
         _scaleX = min(max(_minScaleX, matrix.a), _maxScaleX)