easings.js

export const easeInCubic = (x) => x * x * x;

export const easeInOutSine = (x) => -(Math.cos(Math.PI * x) - 1) / 2;

export const easeInOutBack = (x) => {
  const c1 = 1.70158;
  const c2 = c1 * 1.525;

  return x < 0.5
    ? (Math.pow(2 * x, 2) * ((c2 + 1) * 2 * x - c2)) / 2
    : (Math.pow(2 * x - 2, 2) * ((c2 + 1) * (x * 2 - 2) + c2) + 2) / 2;
};

export const easeOutBack = (x) => {
  const c1 = 1.70158;
  const c3 = c1 + 1;

  return 1 + c3 * Math.pow(x - 1, 3) + c1 * Math.pow(x - 1, 2);
};

export const easeOutCubic = (x) => {
  return 1 - Math.pow(1 - x, 3);
};

export const easeOutElastic = (x) => {
  const c4 = (2 * Math.PI) / 5;

  return x === 0
    ? 0
    : x === 1
    ? 1
    : Math.pow(2, -10 * x) * Math.sin((x * 10 - 0.75) * c4) + 1;
};

export const easeOutQuart = (x) => 1 - Math.pow(1 - x, 4);

export const easeOutCirc = (x) => Math.sqrt(1 - Math.pow(x - 1, 2));

export const easeOutSine = (x) => Math.sin((x * Math.PI) / 2);

export const easeOutQuint = (x) => 1 - Math.pow(1 - x, 5);

export const easeOutQuad = (x) => 1 - (1 - x) * (1 - x);

export const easeOutExpo = (x) => (x === 1 ? 1 : 1 - Math.pow(2, -10 * x));