scroll-custom

This module overwrites the native scrolling in DOM with a customisable script. That's it, really.

I've only tested this with Chromium engines because I intend to use it with Electron apps, but feel free to use it wherever.

How to use

Requiring scroll-custom returns a Scroller constructor:

const Scroller = require('scroll-custom');
let DOMScroller = new Scroller();

To bind the scroller to an element, use the .elem method:

DOMScroller.elem(document.getElementById('element'));

Customisables

To specify direction, friction, magnitude etc., do the same:

DOMScroller.direction('vertical'); // vertical / horizontal, may expand to all directions later
DOMScroller.friction(0.5); // Default 2 - larger values slows scroll down faster
DOMScroller.magnitude(0.1); // Default 0.2 - initial velocity of scroll
DOMScroller.breakAt(1); // Default 1 - greatest velocity to break animation at

.direction specifies which axis the element will scroll through. Default is 'vertical', if the string specified is neither 'vertical' nor 'horizontal', it will default to vertical.

.friction is a constant which reduces the velocity by a set amount every animation frame.

.magnitude is the velocity added to the scroll whenever the scrollwheel is applied.

.breakAt sets the velocity to 0 when the absolute velocity of scrolling decreases to the number specified.

Chaining parameter changes

All the methods specified so far return the parent instance of the Scroller object, so you can chain them like so:

DOMScroller.elem(document.getElementById('element'))
    .direction('vertical') 
    .friction(0.5)
    .magnitude(0.1)
    .breakAt(1);

Initialising scroll animation

Scrolling is not overwritten by default, one must initialise the Scroller object, like so:

DOMScroller.start();

To stop the animation at any time and revert back to the default DOM animation, do:

DOMScroller.stop();

To check whether Scroller is active, use DOMScroller.on.

Example

const Scroller = require('scroll-custom');
let DOMScroller = new Scroller();

DOMScroller.elem(document.body)
    .direction('vertical') 
    .friction(0.5)
    .magnitude(0.1)
    .breakAt(1);

document.body.addEventListener('click', () => {
    if (DOMScroller.on) DOMScroller.stop();
    else DOMScroller.start();
})