Easing curves
Easing curves are functions that operate within the range 0 to 1, and are generally used to transform a linear motion into a more interesting/natural motion.
In
Out
Easings.cs
Struct that contains only a few easing functions in a concise and clean way.
/// <summary>
/// Utility struct full of easing curve functions
/// </summary>
public struct Easings
{
/// <summary>
/// Cubic easing functions
/// </summary>
public struct Cubic
{
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-in ease-out cubic curve
/// </summary>
public static float InOut(float x)
{
float a = -2 * x + 2;
return x < 0.5f ? 4 * x * x * x : 1 - (a * a * a) / 2;
}
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-in cubic curve
/// </summary>
public static float In(float x) => x * x * x;
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-out cubic curve
/// </summary>
public static float Out(float x) => 1 - (1 - x) * (1 - x) * (1 - x);
}
/// <summary>
/// Quadtratic easing functions
/// </summary>
public struct Quad
{
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-in ease-out quadractic curve
/// </summary>
public static float InOut(float x)
{
float a = -2 * x + 2;
return x < 0.5f ? 2 * x * x : 1 - (a * a) / 2;
}
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-in quadractic curve
/// </summary>
public static float In(float x) => x * x;
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-out quadractic curve
/// </summary>
public static float Out(float x) => 1 - (1 - x) * (1 - x);
}
/// <summary>
/// Exponential easing functions
/// </summary>
public struct Expo
{
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-in ease-out exponential curve
/// </summary>
public static float InOut(float x)
{
return x == 0
? 0
: x == 1
? 1
: x < 0.5 ? MathF.Pow(2, 20 * x - 10) / 2
: (2 - MathF.Pow(2, -20 * x + 10)) / 2;
}
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-in exponential curve
/// </summary>
public static float In(float x) => x == 0 ? 0 : MathF.Pow(2, 10 * x - 10);
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-out exponential curve
/// </summary>
public static float Out(float x) => x == 1 ? 1 : 1 - MathF.Pow(2, -10 * x);
}
/// <summary>
/// Circular easing functions
/// </summary>
public struct Circ
{
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-in ease-out circular curve
/// </summary>
public static float InOut(float x)
{
if (x < 0.5)
return (1 - MathF.Sqrt(1 - (2 * x * 2 * x))) / 2;
return (MathF.Sqrt(1 - ((-2 * x + 2) * (-2 * x + 2))) + 1) / 2;
}
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-in circular curve
/// </summary>
public static float In(float x) => 1 - MathF.Sqrt(1 - x * x);
/// <summary>
/// Remaps a linear value from 0 to 1 to an ease-out circular curve
/// </summary>
public static float Out(float x) => MathF.Sqrt(1 - (1 - x) * (1 - x));
}
}
PennerDoubleAnimation.cs
This is a class containing many parametric easing functions. Original source at the top.
// from https://raw.githubusercontent.com/scrudgey/yogurt/refs/heads/master/PennerDoubleAnimation.cs
/**
* PennerDoubleAnimation
* Animates the value of a double property between two target values using
* Robert Penner's easing equations for interpolation over a specified Duration.
*
* @author Darren David [email protected]
* @version 1.0
*
* Credit/Thanks:
* Robert Penner - The easing equations we all know and love
* (http://robertpenner.com/easing/) [See License.txt for license info]
*
* Lee Brimelow - initial port of Penner's equations to WPF
* (http://thewpfblog.com/?p=12)
*
* Zeh Fernando - additional equations (out/in) from
* caurina.transitions.Tweener (http://code.google.com/p/tweener/)
* [See License.txt for license info]
*/
using System;
// using System.Collections.Generic;
// using System.Diagnostics;
// using System.Reflection;
// using System.Text;
// using System.Windows;
// using System.Windows.Media.Animation;
// using System.ComponentModel;
// using System.Globalization;
namespace Easings {
/// <summary>
/// Animates the value of a double property between two target values using
/// Robert Penner's easing equations for interpolation over a specified Duration.
/// </summary>
/// <example>
/// <code>
/// // C#
/// PennerDoubleAnimation anim = new PennerDoubleAnimation();
/// anim.Type = PennerDoubleAnimation.Equations.Linear;
/// anim.From = 1;
/// anim.To = 0;
/// myControl.BeginAnimation( OpacityProperty, anim );
///
/// // XAML
/// <Storyboard x:Key="AnimateXamlRect">
/// <animation:PennerDoubleAnimation
/// Storyboard.TargetName="myControl"
/// Storyboard.TargetProperty="(Canvas.Left)"
/// From="0"
/// To="600"
/// Equation="BackEaseOut"
/// Duration="00:00:05" />
/// </Storyboard>
///
/// <Control.Triggers>
/// <EventTrigger RoutedEvent="FrameworkElement.Loaded">
/// <BeginStoryboard Storyboard="{StaticResource AnimateXamlRect}"/>
/// </EventTrigger>
/// </Control.Triggers>
/// </code>
/// </example>
public class PennerDoubleAnimation {
#region Equations
// These methods are all public to enable reflection in GetCurrentValueCore.
#region Linear
/// <summary>
/// Easing equation function for a simple linear tweening, with no easing.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double Linear(double t, double b, double c, double d) {
return c * t / d + b;
}
#endregion
#region Expo
/// <summary>
/// Easing equation function for an exponential (2^t) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double ExpoEaseOut(double t, double b, double c, double d) {
return (t == d) ? b + c : c * (-Math.Pow(2, -10 * t / d) + 1) + b;
}
/// <summary>
/// Easing equation function for an exponential (2^t) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double ExpoEaseIn(double t, double b, double c, double d) {
return (t == 0) ? b : c * Math.Pow(2, 10 * (t / d - 1)) + b;
}
/// <summary>
/// Easing equation function for an exponential (2^t) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double ExpoEaseInOut(double t, double b, double c, double d) {
if (t == 0)
return b;
if (t == d)
return b + c;
if ((t /= d / 2) < 1)
return c / 2 * Math.Pow(2, 10 * (t - 1)) + b;
return c / 2 * (-Math.Pow(2, -10 * --t) + 2) + b;
}
/// <summary>
/// Easing equation function for an exponential (2^t) easing out/in:
/// deceleration until halfway, then acceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double ExpoEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return ExpoEaseOut(t * 2, b, c / 2, d);
return ExpoEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Circular
/// <summary>
/// Easing equation function for a circular (sqrt(1-t^2)) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double CircEaseOut(double t, double b, double c, double d) {
return c * Math.Sqrt(1 - (t = t / d - 1) * t) + b;
}
/// <summary>
/// Easing equation function for a circular (sqrt(1-t^2)) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double CircEaseIn(double t, double b, double c, double d) {
return -c * (Math.Sqrt(1 - (t /= d) * t) - 1) + b;
}
/// <summary>
/// Easing equation function for a circular (sqrt(1-t^2)) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double CircEaseInOut(double t, double b, double c, double d) {
if ((t /= d / 2) < 1)
return -c / 2 * (Math.Sqrt(1 - t * t) - 1) + b;
return c / 2 * (Math.Sqrt(1 - (t -= 2) * t) + 1) + b;
}
/// <summary>
/// Easing equation function for a circular (sqrt(1-t^2)) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double CircEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return CircEaseOut(t * 2, b, c / 2, d);
return CircEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Quad
/// <summary>
/// Easing equation function for a quadratic (t^2) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuadEaseOut(double t, double b, double c, double d) {
return -c * (t /= d) * (t - 2) + b;
}
/// <summary>
/// Easing equation function for a quadratic (t^2) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuadEaseIn(double t, double b, double c, double d) {
return c * (t /= d) * t + b;
}
/// <summary>
/// Easing equation function for a quadratic (t^2) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuadEaseInOut(double t, double b, double c, double d) {
if ((t /= d / 2) < 1)
return c / 2 * t * t + b;
return -c / 2 * ((--t) * (t - 2) - 1) + b;
}
/// <summary>
/// Easing equation function for a quadratic (t^2) easing out/in:
/// deceleration until halfway, then acceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuadEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return QuadEaseOut(t * 2, b, c / 2, d);
return QuadEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Sine
/// <summary>
/// Easing equation function for a sinusoidal (sin(t)) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double SineEaseOut(double t, double b, double c, double d) {
return c * Math.Sin(t / d * (Math.PI / 2)) + b;
}
/// <summary>
/// Easing equation function for a sinusoidal (sin(t)) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double SineEaseIn(double t, double b, double c, double d) {
return -c * Math.Cos(t / d * (Math.PI / 2)) + c + b;
}
/// <summary>
/// Easing equation function for a sinusoidal (sin(t)) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double SineEaseInOut(double t, double b, double c, double d) {
if ((t /= d / 2) < 1)
return c / 2 * (Math.Sin(Math.PI * t / 2)) + b;
return -c / 2 * (Math.Cos(Math.PI * --t / 2) - 2) + b;
}
/// <summary>
/// Easing equation function for a sinusoidal (sin(t)) easing in/out:
/// deceleration until halfway, then acceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double SineEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return SineEaseOut(t * 2, b, c / 2, d);
return SineEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Cubic
/// <summary>
/// Easing equation function for a cubic (t^3) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double CubicEaseOut(double t, double b, double c, double d) {
return c * ((t = t / d - 1) * t * t + 1) + b;
}
/// <summary>
/// Easing equation function for a cubic (t^3) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double CubicEaseIn(double t, double b, double c, double d) {
return c * (t /= d) * t * t + b;
}
/// <summary>
/// Easing equation function for a cubic (t^3) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double CubicEaseInOut(double t, double b, double c, double d) {
if ((t /= d / 2) < 1)
return c / 2 * t * t * t + b;
return c / 2 * ((t -= 2) * t * t + 2) + b;
}
/// <summary>
/// Easing equation function for a cubic (t^3) easing out/in:
/// deceleration until halfway, then acceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double CubicEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return CubicEaseOut(t * 2, b, c / 2, d);
return CubicEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Quartic
/// <summary>
/// Easing equation function for a quartic (t^4) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuartEaseOut(double t, double b, double c, double d) {
return -c * ((t = t / d - 1) * t * t * t - 1) + b;
}
/// <summary>
/// Easing equation function for a quartic (t^4) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuartEaseIn(double t, double b, double c, double d) {
return c * (t /= d) * t * t * t + b;
}
/// <summary>
/// Easing equation function for a quartic (t^4) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuartEaseInOut(double t, double b, double c, double d) {
if ((t /= d / 2) < 1)
return c / 2 * t * t * t * t + b;
return -c / 2 * ((t -= 2) * t * t * t - 2) + b;
}
/// <summary>
/// Easing equation function for a quartic (t^4) easing out/in:
/// deceleration until halfway, then acceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuartEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return QuartEaseOut(t * 2, b, c / 2, d);
return QuartEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Quintic
/// <summary>
/// Easing equation function for a quintic (t^5) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuintEaseOut(double t, double b, double c, double d) {
return c * ((t = t / d - 1) * t * t * t * t + 1) + b;
}
/// <summary>
/// Easing equation function for a quintic (t^5) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuintEaseIn(double t, double b, double c, double d) {
return c * (t /= d) * t * t * t * t + b;
}
/// <summary>
/// Easing equation function for a quintic (t^5) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuintEaseInOut(double t, double b, double c, double d) {
if ((t /= d / 2) < 1)
return c / 2 * t * t * t * t * t + b;
return c / 2 * ((t -= 2) * t * t * t * t + 2) + b;
}
/// <summary>
/// Easing equation function for a quintic (t^5) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double QuintEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return QuintEaseOut(t * 2, b, c / 2, d);
return QuintEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Elastic
/// <summary>
/// Easing equation function for an elastic (exponentially decaying sine wave) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>`
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double ElasticEaseOut(double t, double b, double c, double d) {
if ((t /= d) == 1)
return b + c;
double p = d * .3;
double s = p / 4;
return (c * Math.Pow(2, -10 * t) * Math.Sin((t * d - s) * (2 * Math.PI) / p) + c + b);
}
/// <summary>
/// Easing equation function for an elastic (exponentially decaying sine wave) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double ElasticEaseIn(double t, double b, double c, double d) {
if ((t /= d) == 1)
return b + c;
double p = d * .3;
double s = p / 4;
return -(c * Math.Pow(2, 10 * (t -= 1)) * Math.Sin((t * d - s) * (2 * Math.PI) / p)) + b;
}
/// <summary>
/// Easing equation function for an elastic (exponentially decaying sine wave) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double ElasticEaseInOut(double t, double b, double c, double d) {
if ((t /= d / 2) == 2)
return b + c;
double p = d * (.3 * 1.5);
double s = p / 4;
if (t < 1)
return -.5 * (c * Math.Pow(2, 10 * (t -= 1)) * Math.Sin((t * d - s) * (2 * Math.PI) / p)) + b;
return c * Math.Pow(2, -10 * (t -= 1)) * Math.Sin((t * d - s) * (2 * Math.PI) / p) * .5 + c + b;
}
/// <summary>
/// Easing equation function for an elastic (exponentially decaying sine wave) easing out/in:
/// deceleration until halfway, then acceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double ElasticEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return ElasticEaseOut(t * 2, b, c / 2, d);
return ElasticEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Bounce
/// <summary>
/// Easing equation function for a bounce (exponentially decaying parabolic bounce) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double BounceEaseOut(double t, double b, double c, double d) {
if ((t /= d) < (1 / 2.75))
return c * (7.5625 * t * t) + b;
else if (t < (2 / 2.75))
return c * (7.5625 * (t -= (1.5 / 2.75)) * t + .75) + b;
else if (t < (2.5 / 2.75))
return c * (7.5625 * (t -= (2.25 / 2.75)) * t + .9375) + b;
else
return c * (7.5625 * (t -= (2.625 / 2.75)) * t + .984375) + b;
}
/// <summary>
/// Easing equation function for a bounce (exponentially decaying parabolic bounce) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double BounceEaseIn(double t, double b, double c, double d) {
return c - BounceEaseOut(d - t, 0, c, d) + b;
}
/// <summary>
/// Easing equation function for a bounce (exponentially decaying parabolic bounce) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double BounceEaseInOut(double t, double b, double c, double d) {
if (t < d / 2)
return BounceEaseIn(t * 2, 0, c, d) * .5 + b;
else
return BounceEaseOut(t * 2 - d, 0, c, d) * .5 + c * .5 + b;
}
/// <summary>
/// Easing equation function for a bounce (exponentially decaying parabolic bounce) easing out/in:
/// deceleration until halfway, then acceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double BounceEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return BounceEaseOut(t * 2, b, c / 2, d);
return BounceEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#region Back
/// <summary>
/// Easing equation function for a back (overshooting cubic easing: (s+1)*t^3 - s*t^2) easing out:
/// decelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double BackEaseOut(double t, double b, double c, double d) {
return c * ((t = t / d - 1) * t * ((1.70158 + 1) * t + 1.70158) + 1) + b;
}
/// <summary>
/// Easing equation function for a back (overshooting cubic easing: (s+1)*t^3 - s*t^2) easing in:
/// accelerating from zero velocity.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double BackEaseIn(double t, double b, double c, double d) {
return c * (t /= d) * t * ((1.70158 + 1) * t - 1.70158) + b;
}
/// <summary>
/// Easing equation function for a back (overshooting cubic easing: (s+1)*t^3 - s*t^2) easing in/out:
/// acceleration until halfway, then deceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double BackEaseInOut(double t, double b, double c, double d) {
double s = 1.70158;
if ((t /= d / 2) < 1)
return c / 2 * (t * t * (((s *= (1.525)) + 1) * t - s)) + b;
return c / 2 * ((t -= 2) * t * (((s *= (1.525)) + 1) * t + s) + 2) + b;
}
/// <summary>
/// Easing equation function for a back (overshooting cubic easing: (s+1)*t^3 - s*t^2) easing out/in:
/// deceleration until halfway, then acceleration.
/// </summary>
/// <param name="t">Current time in seconds.</param>
/// <param name="b">Starting value.</param>
/// <param name="c">Final value.</param>
/// <param name="d">Duration of animation.</param>
/// <returns>The correct value.</returns>
public static double BackEaseOutIn(double t, double b, double c, double d) {
if (t < d / 2)
return BackEaseOut(t * 2, b, c / 2, d);
return BackEaseIn((t * 2) - d, b + c / 2, c / 2, d);
}
#endregion
#endregion
}
}