text: /* jshint curly: false */
  
  /**
  * @author       Richard Davey <rich@photonstorm.com>
  * @copyright    2016 Photon Storm Ltd.
  * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
  */
  
  /**
  * A collection of easing methods defining ease-in and ease-out curves.
  *
  * @class Phaser.Easing
  */
  Phaser.Easing = {
  
      /**
      * Linear easing.
      *
      * @class Phaser.Easing.Linear
      */
      Linear: {
  
          /**
          * Linear Easing (no variation).
          *
          * @method Phaser.Easing.Linear#None
          * @param {number} k - The value to be tweened.
          * @returns {number} k.
          */
          None: function ( k ) {
  
              return k;
  
          }
  
      },
  
      /**
      * Quadratic easing.
      *
      * @class Phaser.Easing.Quadratic
      */
      Quadratic: {
  
          /**
          * Ease-in.
          *
          * @method Phaser.Easing.Quadratic#In
          * @param {number} k - The value to be tweened.
          * @returns {number} k^2.
          */
          In: function ( k ) {
  
              return k * k;
  
          },
  
          /**
          * Ease-out.
          *
          * @method Phaser.Easing.Quadratic#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} k* (2-k).
          */
          Out: function ( k ) {
  
              return k * ( 2 - k );
  
          },
  
          /**
          * Ease-in/out.
          *
          * @method Phaser.Easing.Quadratic#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              if ( ( k *= 2 ) < 1 ) return 0.5 * k * k;
              return - 0.5 * ( --k * ( k - 2 ) - 1 );
  
          }
  
      },
  
      /**
      * Cubic easing.
      *
      * @class Phaser.Easing.Cubic
      */
      Cubic: {
  
          /**
          * Cubic ease-in.
          *
          * @method Phaser.Easing.Cubic#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              return k * k * k;
  
          },
  
          /**
          * Cubic ease-out.
          *
          * @method Phaser.Easing.Cubic#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              return --k * k * k + 1;
  
          },
  
          /**
          * Cubic ease-in/out.
          *
          * @method Phaser.Easing.Cubic#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              if ( ( k *= 2 ) < 1 ) return 0.5 * k * k * k;
              return 0.5 * ( ( k -= 2 ) * k * k + 2 );
  
          }
  
      },
  
      /**
      * Quartic easing.
      *
      * @class Phaser.Easing.Quartic
      */
      Quartic: {
  
          /**
          * Quartic ease-in.
          *
          * @method Phaser.Easing.Quartic#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              return k * k * k * k;
  
          },
  
          /**
          * Quartic ease-out.
          *
          * @method Phaser.Easing.Quartic#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              return 1 - ( --k * k * k * k );
  
          },
  
          /**
          * Quartic ease-in/out.
          *
          * @method Phaser.Easing.Quartic#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              if ( ( k *= 2 ) < 1) return 0.5 * k * k * k * k;
              return - 0.5 * ( ( k -= 2 ) * k * k * k - 2 );
  
          }
  
      },
  
      /**
      * Quintic easing.
      *
      * @class Phaser.Easing.Quintic
      */
      Quintic: {
  
          /**
          * Quintic ease-in.
          *
          * @method Phaser.Easing.Quintic#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              return k * k * k * k * k;
  
          },
  
          /**
          * Quintic ease-out.
          *
          * @method Phaser.Easing.Quintic#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              return --k * k * k * k * k + 1;
  
          },
  
          /**
          * Quintic ease-in/out.
          *
          * @method Phaser.Easing.Quintic#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              if ( ( k *= 2 ) < 1 ) return 0.5 * k * k * k * k * k;
              return 0.5 * ( ( k -= 2 ) * k * k * k * k + 2 );
  
          }
  
      },
  
      /**
      * Sinusoidal easing.
      *
      * @class Phaser.Easing.Sinusoidal
      */
      Sinusoidal: {
  
          /**
          * Sinusoidal ease-in.
          *
          * @method Phaser.Easing.Sinusoidal#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              if (k === 0) return 0;
              if (k === 1) return 1;
              return 1 - Math.cos( k * Math.PI / 2 );
  
          },
  
          /**
          * Sinusoidal ease-out.
          *
          * @method Phaser.Easing.Sinusoidal#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              if (k === 0) return 0;
              if (k === 1) return 1;
              return Math.sin( k * Math.PI / 2 );
  
          },
  
          /**
          * Sinusoidal ease-in/out.
          *
          * @method Phaser.Easing.Sinusoidal#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              if (k === 0) return 0;
              if (k === 1) return 1;
              return 0.5 * ( 1 - Math.cos( Math.PI * k ) );
  
          }
  
      },
  
      /**
      * Exponential easing.
      *
      * @class Phaser.Easing.Exponential
      */
      Exponential: {
  
          /**
          * Exponential ease-in.
          *
          * @method Phaser.Easing.Exponential#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              return k === 0 ? 0 : Math.pow( 1024, k - 1 );
  
          },
  
          /**
          * Exponential ease-out.
          *
          * @method Phaser.Easing.Exponential#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              return k === 1 ? 1 : 1 - Math.pow( 2, - 10 * k );
  
          },
  
          /**
          * Exponential ease-in/out.
          *
          * @method Phaser.Easing.Exponential#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              if ( k === 0 ) return 0;
              if ( k === 1 ) return 1;
              if ( ( k *= 2 ) < 1 ) return 0.5 * Math.pow( 1024, k - 1 );
              return 0.5 * ( - Math.pow( 2, - 10 * ( k - 1 ) ) + 2 );
  
          }
  
      },
  
      /**
      * Circular easing.
      *
      * @class Phaser.Easing.Circular
      */
      Circular: {
  
          /**
          * Circular ease-in.
          *
          * @method Phaser.Easing.Circular#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              return 1 - Math.sqrt( 1 - k * k );
  
          },
  
          /**
          * Circular ease-out.
          *
          * @method Phaser.Easing.Circular#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              return Math.sqrt( 1 - ( --k * k ) );
  
          },
  
          /**
          * Circular ease-in/out.
          *
          * @method Phaser.Easing.Circular#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              if ( ( k *= 2 ) < 1) return - 0.5 * ( Math.sqrt( 1 - k * k) - 1);
              return 0.5 * ( Math.sqrt( 1 - ( k -= 2) * k) + 1);
  
          }
  
      },
  
      /**
      * Elastic easing.
      *
      * @class Phaser.Easing.Elastic
      */
      Elastic: {
  
          /**
          * Elastic ease-in.
          *
          * @method Phaser.Easing.Elastic#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              var s, a = 0.1, p = 0.4;
              if ( k === 0 ) return 0;
              if ( k === 1 ) return 1;
              if ( !a || a < 1 ) { a = 1; s = p / 4; }
              else s = p * Math.asin( 1 / a ) / ( 2 * Math.PI );
              return - ( a * Math.pow( 2, 10 * ( k -= 1 ) ) * Math.sin( ( k - s ) * ( 2 * Math.PI ) / p ) );
  
          },
  
          /**
          * Elastic ease-out.
          *
          * @method Phaser.Easing.Elastic#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              var s, a = 0.1, p = 0.4;
              if ( k === 0 ) return 0;
              if ( k === 1 ) return 1;
              if ( !a || a < 1 ) { a = 1; s = p / 4; }
              else s = p * Math.asin( 1 / a ) / ( 2 * Math.PI );
              return ( a * Math.pow( 2, - 10 * k) * Math.sin( ( k - s ) * ( 2 * Math.PI ) / p ) + 1 );
  
          },
  
          /**
          * Elastic ease-in/out.
          *
          * @method Phaser.Easing.Elastic#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              var s, a = 0.1, p = 0.4;
              if ( k === 0 ) return 0;
              if ( k === 1 ) return 1;
              if ( !a || a < 1 ) { a = 1; s = p / 4; }
              else s = p * Math.asin( 1 / a ) / ( 2 * Math.PI );
              if ( ( k *= 2 ) < 1 ) return - 0.5 * ( a * Math.pow( 2, 10 * ( k -= 1 ) ) * Math.sin( ( k - s ) * ( 2 * Math.PI ) / p ) );
              return a * Math.pow( 2, -10 * ( k -= 1 ) ) * Math.sin( ( k - s ) * ( 2 * Math.PI ) / p ) * 0.5 + 1;
  
          }
  
      },
  
      /**
      * Back easing.
      *
      * @class Phaser.Easing.Back
      */
      Back: {
  
          /**
          * Back ease-in.
          *
          * @method Phaser.Easing.Back#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              var s = 1.70158;
              return k * k * ( ( s + 1 ) * k - s );
  
          },
  
          /**
          * Back ease-out.
          *
          * @method Phaser.Easing.Back#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              var s = 1.70158;
              return --k * k * ( ( s + 1 ) * k + s ) + 1;
  
          },
  
          /**
          * Back ease-in/out.
          *
          * @method Phaser.Easing.Back#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              var s = 1.70158 * 1.525;
              if ( ( k *= 2 ) < 1 ) return 0.5 * ( k * k * ( ( s + 1 ) * k - s ) );
              return 0.5 * ( ( k -= 2 ) * k * ( ( s + 1 ) * k + s ) + 2 );
  
          }
  
      },
  
      /**
      * Bounce easing.
      *
      * @class Phaser.Easing.Bounce
      */
      Bounce: {
  
          /**
          * Bounce ease-in.
          *
          * @method Phaser.Easing.Bounce#In
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          In: function ( k ) {
  
              return 1 - Phaser.Easing.Bounce.Out( 1 - k );
  
          },
  
          /**
          * Bounce ease-out.
          *
          * @method Phaser.Easing.Bounce#Out
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          Out: function ( k ) {
  
              if ( k < ( 1 / 2.75 ) ) {
  
                  return 7.5625 * k * k;
  
              } else if ( k < ( 2 / 2.75 ) ) {
  
                  return 7.5625 * ( k -= ( 1.5 / 2.75 ) ) * k + 0.75;
  
              } else if ( k < ( 2.5 / 2.75 ) ) {
  
                  return 7.5625 * ( k -= ( 2.25 / 2.75 ) ) * k + 0.9375;
  
              } else {
  
                  return 7.5625 * ( k -= ( 2.625 / 2.75 ) ) * k + 0.984375;
  
              }
  
          },
  
          /**
          * Bounce ease-in/out.
          *
          * @method Phaser.Easing.Bounce#InOut
          * @param {number} k - The value to be tweened.
          * @returns {number} The tweened value.
          */
          InOut: function ( k ) {
  
              if ( k < 0.5 ) return Phaser.Easing.Bounce.In( k * 2 ) * 0.5;
              return Phaser.Easing.Bounce.Out( k * 2 - 1 ) * 0.5 + 0.5;
  
          }
  
      }
  
  };
  
  Phaser.Easing.Default = Phaser.Easing.Linear.None;
  Phaser.Easing.Power0 = Phaser.Easing.Linear.None;
  Phaser.Easing.Power1 = Phaser.Easing.Quadratic.Out;
  Phaser.Easing.Power2 = Phaser.Easing.Cubic.Out;
  Phaser.Easing.Power3 = Phaser.Easing.Quartic.Out;
  Phaser.Easing.Power4 = Phaser.Easing.Quintic.Out;
  