jquery vertical mousewheel smooth scrolling

Question

I'm making a parallax website and I would like to make the page scroll smoother with the mousewheel for a better user experience. The best example I could get was this website: http://www.milwaukeepolicenews.com/#menu=home-page It would be great if I could get something similar to that into my website, the smooth vertical scrolling and scroll inertia.

I noticed they are using Brandon Aaron's jQuery mousewheel which is very light but I'm just a beginner and cannot make it work by myself.

Also i noticed this in their mpd-parallax.js:

jQuery(window).mousewheel(function(event, delta, deltaX, deltaY){         if(delta < 0) page.scrollTop(page.scrollTop() + 65);         else if(delta > 0) page.scrollTop(page.scrollTop() - 65);         return false;     }) 

Thank you!

EDIT

I'm almost there. Take a look at this fiddle: http://jsfiddle.net/gmelcul/cZuym/ It only needs adding an easing method to scroll just like the Milwaukee Police website.

Answer 1

I know it's a really old post, but here is a good solution I made :

function handle(delta) {     var animationInterval = 20; //lower is faster   var scrollSpeed = 20; //lower is faster      if (end == null) {     end = $(window).scrollTop();   }   end -= 20 * delta;   goUp = delta > 0;    if (interval == null) {     interval = setInterval(function () {       var scrollTop = $(window).scrollTop();       var step = Math.round((end - scrollTop) / scrollSpeed);       if (scrollTop <= 0 ||            scrollTop >= $(window).prop("scrollHeight") - $(window).height() ||           goUp && step > -1 ||            !goUp && step < 1 ) {         clearInterval(interval);         interval = null;         end = null;       }       $(window).scrollTop(scrollTop + step );     }, animationInterval);   } } 

Test it : http://jsfiddle.net/y4swj2ts/3/

Answer 2

Here are two jsfiddles -- one with the script and one without it so you can compare:

• with script
• without script

JavaScript using the jQuery mousewheel plugin:

$(document).ready(function() {     var page = $('#content');  // set to the main content of the page        $(window).mousewheel(function(event, delta, deltaX, deltaY){         if (delta < 0) page.scrollTop(page.scrollTop() + 65);         else if (delta > 0) page.scrollTop(page.scrollTop() - 65);         return false;     }) }); 

Compare the two. From what I can tell, the script slows the mouse wheel so it requires more physically turning to scroll the same distance as without the script. It may feel smoother because of that slower scrolling (and it may indeed be smoother as it is probably easier on the graphics unit).