scrollto-with-animation/src/easings.js

Animated scroll with requestAnimationFrame. For smooth animate scrollTo defining the easing, running at 60FPS and cross-browser

export default {
  linearTween: function (t, b, c, d) {
    return c * t / d + b
  },
  easeInQuad: function (t, b, c, d) {
    t /= d
    return c * t * t + b
  },
  easeOutQuad: function (t, b, c, d) {
    t /= d
    return -c * t * (t - 2) + b
  },
  easeInOutQuad: function (t, b, c, d) {
    t /= d / 2
    if (t < 1) return c / 2 * t * t + b
    t--
    return -c / 2 * (t * (t - 2) - 1) + b
  },
  easeInCubic: function (t, b, c, d) {
    t /= d
    return c * t * t * t + b
  },
  easeOutCubic: function (t, b, c, d) {
    t /= d
    t--
    return c * (t * t * t + 1) + b
  },
  easeInOutCubic: function (t, b, c, d) {
    t /= d / 2
    if (t < 1) return c / 2 * t * t * t + b
    t -= 2
    return c / 2 * (t * t * t + 2) + b
  },
  easeInQuart: function (t, b, c, d) {
    t /= d
    return c * t * t * t * t + b
  },
  easeOutQuart: function (t, b, c, d) {
    t /= d
    t--
    return -c * (t * t * t * t - 1) + b
  },
  easeInOutQuart: function (t, b, c, d) {
    t /= d / 2
    if (t < 1) return c / 2 * t * t * t * t + b
    t -= 2
    return -c / 2 * (t * t * t * t - 2) + b
  },
  easeInQuint: function (t, b, c, d) {
    t /= d
    return c * t * t * t * t * t + b
  },
  easeOutQuint: function (t, b, c, d) {
    t /= d
    t--
    return c * (t * t * t * t * t + 1) + b
  },
  easeInOutQuint: function (t, b, c, d) {
    t /= d / 2
    if (t < 1) return c / 2 * t * t * t * t * t + b
    t -= 2
    return c / 2 * (t * t * t * t * t + 2) + b
  },
  easeInSine: function (t, b, c, d) {
    return -c * Math.cos(t / d * (Math.PI / 2)) + c + b
  },
  easeOutSine: function (t, b, c, d) {
    return c * Math.sin(t / d * (Math.PI / 2)) + b
  },
  easeInOutSine: function (t, b, c, d) {
    return -c / 2 * (Math.cos(Math.PI * t / d) - 1) + b
  },
  easeInExpo: function (t, b, c, d) {
    return c * Math.pow(2, 10 * (t / d - 1)) + b
  },
  easeOutExpo: function (t, b, c, d) {
    return c * (-Math.pow(2, -10 * t / d) + 1) + b
  },
  easeInOutExpo: function (t, b, c, d) {
    t /= d / 2
    if (t < 1) return c / 2 * Math.pow(2, 10 * (t - 1)) + b
    t--
    return c / 2 * (-Math.pow(2, -10 * t) + 2) + b
  },
  easeInCirc: function (t, b, c, d) {
    t /= d
    return -c * (Math.sqrt(1 - t * t) - 1) + b
  },
  easeOutCirc: function (t, b, c, d) {
    t /= d
    t--
    return c * Math.sqrt(1 - t * t) + b
  },
  easeInOutCirc: function (t, b, c, d) {
    t /= d / 2
    if (t < 1) return -c / 2 * (Math.sqrt(1 - t * t) - 1) + b
    t -= 2
    return c / 2 * (Math.sqrt(1 - t * t) + 1) + b
  }
}