Calculates mouse speed during the mousemove event, returning x and y speed values.

mouse-speed can be used in two ways:

const mouseSpeed = require('mouse-speed');

window.addEventListener('mousemove', (event) => {
  const speed = mouseSpeed(event);
  console.log(speed.x, speed.y);
})

Put mouse-speed in a mousemove event handler and pass it the event object.

Speed is calculated and returned as an object with x and y values.

const mouseSpeed = require('mouse-speed');

const speedTracker = {};

window.addEventListener('mousemove', (event) => {
  const speed = mouseSpeed(event, speedTracker);
  console.log(speedTracker.speedX, speedTracker.speedY);
})

Optionally, an object can be passed to it.

This object will now have two new values, accessible as speedX and speedY.

MIT, see LICENSE.md for details.