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Comment by addisonj | Hacker News Reader

I am lazy and (apparently) suck at scrolling smoothly, dropping this in the console worked well :)

    setInterval(function() {
      window.scrollTo(0, document.body.scrollTop + 5)
    }, 60)

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Setting the scroll increment to 5px diminishes the lenticular effect; it's like skipping frames in film. Your mind interpolates the result, but it's not as smooth as scrolling by 1px and reducing the time interval to speed things up instead.

Try this one instead to see the difference. This will scroll at approximately the same rate as your example:

setInterval(function() { window.scrollTo(0, document.body.scrollTop + 1) }, 12);

I prefer it a bit slower though:

setInterval(function() { window.scrollTo(0, document.body.scrollTop + 1) }, 30);

No need to use the console either. Just put bradleyland's suggestion in the address bar prefixed by javascript:

javascript:setInterval(function() { window.scrollTo(0, document.body.scrollTop + 1) }, 30);

I'm curious what browser you use. I was under the impression that most of the major browsers had disabled the ability to type javascript: URLs because of self-XSS (which is a fascinating concept on the border between computer exploit and human exploit).

On Chrome 39 on CrOS, I can't type that into the URL field, and if I copy/paste it, the "javascript:" portion of the scheme magically disappears, so hitting enter takes me to a SERP. I wonder if that's done in the hope that you Google the self-XSS that you were about to run and see someone explain what's going on.

The initial "javascript:" gets stripped on paste but you can add it back manually.

I am lazy and suck at scrolling smoothly, so I middle-click to get the scroll tool set-point, then move my pointer a little below the set-point to indicate that I wish to scroll down slowly. Works in FF and Chrome.

Isn't this how everyone scrolls slowly?

Middle-click usually pastes stuff you selected on Linux, so not everyone. However if I enable autoscrolling then middle-click works as you described, quite useful!

This worked like a charm on Firefox! It is also much better when squinting.

That didn't work in Firefox for me but this one does:

setInterval(function () { window.scrollTo(0, document.documentElement.scrollTop + 5); }, 60)

in IE/Firefox you can click the middle mouse button to get smooth constant scrolling. Chrome probably does this as well

> and math

do this instead for 60 intervals per second: setInterval(function() { window.scrollTo(0, document.body.scrollTop + 5) }, 16.666666666666668)

or better yet skip the setInterval and have the page continue to move:

    var scrollIncrement = 5;
    var height = Math.max( document.body.scrollHeight, document.body.offsetHeight, document.documentElement.clientHeight, document.documentElement.scrollHeight, document.documentElement.offsetHeight ) - window.innerHeight;
    var AnimationFrame = (function() {
        var FPS = 16.6666666667; // 1000 / 60 = Frames Per Second
        var RAF = window.requestAnimationFrame
                || window.webkitRequestAnimationFrame
                || window.mozRequestAnimationFrame
                || window.msRequestAnimationFrame
                || window.oRequestAnimationFrame
                || function(a) { window.setTimeout(a, FPS); }
        var CAF = window.cancelAnimationFrame
                || window.webkitCancelAnimationFrame
                || window.mozCancelAnimationFrame
                || window.msCancelAnimationFrame
                || window.oCancelAnimationFrame
                || function(a) { window.clearTimeout(a); }
        return {
            request: function(a) {
                RAF(a);
            },
            cancel: function(a) {
                CAF(a);
            }
        }
    })();


    var scroll = function(){
        var scrollPosition = Math.max( document.documentElement.scrollTop, document.body.scrollTop );
        if ( scrollPosition == height )
            scrollIncrement = (-1 * scrollIncrement);
        else if ( scrollPosition == 0 )
            scrollIncrement = (-1 * scrollIncrement);
        window.scrollBy(0, scrollIncrement);
        AnimationFrame.request(scroll);
    }

    AnimationFrame.request(scroll);

you can easily just tweak the scroll distance as well by entering scrollIncrement = x;

I held down the "down arrow"

In Chrome, that was a bit jumpy compared to using the scroll bar.

Thanks!

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