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diff --git a/xbmc/guilib/Tween.h b/xbmc/guilib/Tween.h
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+/*
+ *  Copyright (C) 2005-2018 Team Kodi
+ *  This file is part of Kodi - https://kodi.tv
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ *  See LICENSES/README.md for more information.
+ */
+
+#pragma once
+
+///////////////////////////////////////////////////////////////////////
+// Tween.h
+// A couple of tweening classes implemented in C++.
+// ref: http://www.robertpenner.com/easing/
+//
+// Author: d4rk <d4rk@xbmc.org>
+///////////////////////////////////////////////////////////////////////
+
+
+///////////////////////////////////////////////////////////////////////
+// Current list of classes:
+//
+// LinearTweener
+// QuadTweener
+// CubicTweener
+// SineTweener
+// CircleTweener
+// BackTweener
+// BounceTweener
+// ElasticTweener
+//
+///////////////////////////////////////////////////////////////////////
+
+#include <math.h>
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+enum TweenerType
+{
+  EASE_IN,
+  EASE_OUT,
+  EASE_INOUT
+};
+
+
+class Tweener
+{
+public:
+  explicit Tweener(TweenerType tweenerType = EASE_OUT) { m_tweenerType = tweenerType; }
+  virtual ~Tweener() = default;
+
+  void SetEasing(TweenerType type) { m_tweenerType = type; }
+  virtual float Tween(float time, float start, float change, float duration)=0;
+  virtual bool HasResumePoint() const { return m_tweenerType == EASE_INOUT; }
+protected:
+  TweenerType m_tweenerType;
+};
+
+
+class LinearTweener : public Tweener
+{
+public:
+  float Tween(float time, float start, float change, float duration) override
+  {
+    return change * time / duration + start;
+  }
+  bool HasResumePoint() const override { return false; }
+};
+
+
+class QuadTweener : public Tweener
+{
+public:
+  explicit QuadTweener(float a = 1.0f) { _a=a; }
+  float Tween(float time, float start, float change, float duration) override
+  {
+    switch (m_tweenerType)
+      {
+      case EASE_IN:
+        time /= duration;
+        return change * time * (_a * time + 1 - _a) + start;
+        break;
+
+      case EASE_OUT:
+        time /= duration;
+        return -change * time * (_a * time - 1 - _a) + start;
+        break;
+
+      case EASE_INOUT:
+        time /= duration/2;
+        if (time < 1)
+          return (change) * time * (_a * time + 1 - _a) + start;
+        time--;
+        return (-change) * time * (_a * time - 1 - _a) + start;
+        break;
+      }
+    return change * time * time + start;
+  }
+private:
+  float _a;
+};
+
+
+class CubicTweener : public Tweener
+{
+public:
+  float Tween(float time, float start, float change, float duration) override
+  {
+    switch (m_tweenerType)
+      {
+      case EASE_IN:
+        time /= duration;
+        return change * time * time * time + start;
+        break;
+
+      case EASE_OUT:
+        time /= duration;
+        time--;
+        return change * (time * time * time + 1) + start;
+        break;
+
+      case EASE_INOUT:
+        time /= duration/2;
+        if (time < 1)
+          return (change/2) * time * time * time + start;
+        time-=2;
+        return (change/2) * (time * time * time + 2) + start;
+        break;
+      }
+    return change * time * time + start;
+  }
+};
+
+class CircleTweener : public Tweener
+{
+public:
+  float Tween(float time, float start, float change, float duration) override
+  {
+    switch (m_tweenerType)
+      {
+      case EASE_IN:
+        time /= duration;
+        return (-change) * (sqrt(1 - time * time) - 1) + start;
+        break;
+
+      case EASE_OUT:
+        time /= duration;
+        time--;
+        return change * sqrt(1 - time * time) + start;
+        break;
+
+      case EASE_INOUT:
+        time /= duration/2;
+        if (time  < 1)
+          return (-change/2) * (sqrt(1 - time * time) - 1) + start;
+        time-=2;
+        return change/2 * (sqrt(1 - time * time) + 1) + start;
+        break;
+      }
+    return change * sqrt(1 - time * time) + start;
+  }
+};
+
+class BackTweener : public Tweener
+{
+public:
+  explicit BackTweener(float s=1.70158) { _s=s; }
+
+  float Tween(float time, float start, float change, float duration) override
+  {
+    float s = _s;
+    switch (m_tweenerType)
+      {
+      case EASE_IN:
+        time /= duration;
+        return change * time * time * ((s + 1) * time - s) + start;
+        break;
+
+      case EASE_OUT:
+        time /= duration;
+        time--;
+        return change * (time * time * ((s + 1) * time + s) + 1) + start;
+        break;
+
+      case EASE_INOUT:
+        time /= duration/2;
+        s*=(1.525f);
+        if ((time ) < 1)
+        {
+          return (change/2) * (time * time * ((s + 1) * time - s)) + start;
+        }
+        time-=2;
+        return (change/2) * (time * time * ((s + 1) * time + s) + 2) + start;
+        break;
+      }
+    return change * ((time-1) * time * ((s + 1) * time + s) + 1) + start;
+  }
+private:
+  float _s;
+
+};
+
+
+class SineTweener : public Tweener
+{
+public:
+  float Tween(float time, float start, float change, float duration) override
+  {
+    time /= duration;
+    switch (m_tweenerType)
+      {
+      case EASE_IN:
+        return change * (1 - cos(time * static_cast<float>(M_PI) / 2.0f)) + start;
+        break;
+
+      case EASE_OUT:
+        return change * sin(time * static_cast<float>(M_PI) / 2.0f) + start;
+        break;
+
+      case EASE_INOUT:
+        return change / 2 * (1 - cos(static_cast<float>(M_PI) * time)) + start;
+        break;
+      }
+      return (change / 2) * (1 - cos(static_cast<float>(M_PI) * time)) + start;
+  }
+};
+
+
+class BounceTweener : public Tweener
+{
+public:
+  float Tween(float time, float start, float change, float duration) override
+  {
+    switch (m_tweenerType)
+      {
+      case EASE_IN:
+        return (change - easeOut(duration - time, 0, change, duration)) + start;
+        break;
+
+      case EASE_OUT:
+        return easeOut(time, start, change, duration);
+        break;
+
+      case EASE_INOUT:
+        if (time < duration/2)
+          return (change - easeOut (duration - (time * 2), 0, change, duration) + start) * .5f + start;
+        else
+          return (easeOut (time * 2 - duration, 0, change, duration) * .5f + change * .5f) + start;
+        break;
+      }
+
+    return easeOut(time, start, change, duration);
+  }
+protected:
+  static float easeOut(float time, float start, float change, float duration)
+  {
+    time /= duration;
+    if (time < (1 / 2.75f))
+    {
+      return  change * (7.5625f * time * time) + start;
+    }
+    else if (time < (2 / 2.75f))
+    {
+      time -= (1.5f/2.75f);
+      return change * (7.5625f * time * time + .75f) + start;
+    }
+    else if (time < (2.5f / 2.75f))
+    {
+      time -= (2.25f/2.75f);
+      return change * (7.5625f * time * time + .9375f) + start;
+    }
+    else
+    {
+      time -= (2.625f/2.75f);
+      return change * (7.5625f * time * time + .984375f) + start;
+    }
+  }
+};
+
+
+class ElasticTweener : public Tweener
+{
+public:
+  ElasticTweener(float a=0.0, float p=0.0) { _a=a; _p=p; }
+
+  float Tween(float time, float start, float change, float duration) override
+  {
+    switch (m_tweenerType)
+      {
+      case EASE_IN:
+        return easeIn(time, start, change, duration);
+        break;
+
+      case EASE_OUT:
+        return easeOut(time, start, change, duration);
+        break;
+
+      case EASE_INOUT:
+        return easeInOut(time, start, change, duration);
+        break;
+      }
+    return easeOut(time, start, change, duration);
+  }
+protected:
+  float _a;
+  float _p;
+
+  float easeIn(float time, float start, float change, float duration) const
+  {
+    float s=0;
+    float a=_a;
+    float p=_p;
+
+    if (time==0)
+      return start;
+    time /= duration;
+    if (time==1)
+        return start + change;
+    if (!p)
+      p=duration*.3f;
+    if (!a || a < fabs(change))
+    {
+      a = change;
+      s = p / 4.0f;
+    }
+    else
+    {
+      s = p / (2 * static_cast<float>(M_PI)) * asin(change / a);
+    }
+    time--;
+    return -(a * pow(2.0f, 10 * time) *
+             sin((time * duration - s) * (2 * static_cast<float>(M_PI)) / p)) +
+           start;
+  }
+
+  float easeOut(float time, float start, float change, float duration) const
+  {
+    float s=0;
+    float a=_a;
+    float p=_p;
+
+    if (time==0)
+      return start;
+    time /= duration;
+    if (time==1)
+        return start + change;
+    if (!p)
+      p=duration*.3f;
+    if (!a || a < fabs(change))
+    {
+      a = change;
+      s = p / 4.0f;
+    }
+    else
+    {
+      s = p / (2 * static_cast<float>(M_PI)) * asin(change / a);
+    }
+    return (a * pow(2.0f, -10 * time) *
+            sin((time * duration - s) * (2 * static_cast<float>(M_PI)) / p)) +
+           change + start;
+  }
+
+  float easeInOut(float time, float start, float change, float duration) const
+  {
+    float s=0;
+    float a=_a;
+    float p=_p;
+
+    if (time==0)
+      return start;
+    time /= duration/2;
+    if (time==2)
+        return start + change;
+    if (!p)
+      p=duration*.3f*1.5f;
+    if (!a || a < fabs(change))
+    {
+      a = change;
+      s = p / 4.0f;
+    }
+    else
+    {
+      s = p / (2 * static_cast<float>(M_PI)) * asin(change / a);
+    }
+
+    if (time < 1)
+    {
+      time--;
+      return -.5f * (a * pow(2.0f, 10 * (time)) *
+                     sin((time * duration - s) * (2 * static_cast<float>(M_PI)) / p)) +
+             start;
+    }
+    time--;
+    return a * pow(2.0f, -10 * (time)) *
+               sin((time * duration - s) * (2 * static_cast<float>(M_PI)) / p) * .5f +
+           change + start;
+  }
+};
+