emile/src/easings.js

no-thrills stand-alone CSS animation JavaScript framework

var easings = {
  easeOut: function (t) {
    return Math.sin(t * Math.PI / 2);
  },

  easeOutStrong: function (t) {
    return (t == 1) ? 1 : 1 - Math.pow(2, -10 * t);
  },

  easeIn: function (t) {
    return t * t;
  },

  easeInStrong: function (t) {
    return (t == 0) ? 0 : Math.pow(2, 10 * (t - 1));
  },

  bounce: function (t) {
    if (t < (1 / 2.75)) {
      return 7.5625 * t * t;
    }
    if (t < (2 / 2.75)) {
      return 7.5625 * (t-= (1.5 / 2.75)) * t + 0.75;
    }
    if (t < (2.5 / 2.75)) {
      return 7.5625 * (t -= (2.25 / 2.75)) * t + 0.9375;
    }
    return 7.5625 * (t -= (2.625 / 2.75)) * t + 0.984375;
  }
};