Last active
July 12, 2016 14:28
-
-
Save grayghostvisuals/ae57d794d1d9e779a120 to your computer and use it in GitHub Desktop.
Anchor Scroll w/Vanilla JS (also displays hash value)
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| var scrollmation_parent = document.getElementById(parent_el).nextElementSibling; | |
| var easing = { | |
| linear: function (t) { return t; }, | |
| easeInQuad: function (t) { return t*t; }, | |
| easeOutQuad: function (t) { return t*(2-t); }, | |
| easeInOutQuad: function (t) { return t < 0.5 ? 2*t*t : -1+(4-2*t)*t; }, | |
| easeInCubic: function (t) { return t*t*t; }, | |
| easeOutCubic: function (t) { return (--t)*t*t+1; }, | |
| easeInOutCubic: function (t) { return t < 0.5 ? 4*t*t*t : (t-1)*(2*t-2)*(2*t-2)+1; }, | |
| easeInQuart: function (t) { return t*t*t*t; }, | |
| easeOutQuart: function (t) { return 1-(--t)*t*t*t; }, | |
| easeInOutQuart: function (t) { return t < 0.5 ? 8*t*t*t*t : 1-8*(--t)*t*t*t; }, | |
| easeInQuint: function (t) { return t*t*t*t*t; }, | |
| easeOutQuint: function (t) { return 1+(--t)*t*t*t*t; }, | |
| easeInOutQuint: function (t) { return t < 0.5 ? 16*t*t*t*t*t : 1+16*(--t)*t*t*t*t; } | |
| }; | |
| function scrollTo(Y, duration, easingFunction, callback) { | |
| var start = Date.now(), | |
| elem = document.documentElement.scrollTop ? document.documentElement:document.body, | |
| from = elem.scrollTop; | |
| if(from === Y) { | |
| callback(); | |
| return; | |
| } | |
| function min(a,b) { | |
| return a<b?a:b; | |
| } | |
| function scroll(timestamp) { | |
| var currentTime = Date.now(), | |
| time = min(1, ((currentTime - start) / duration)), | |
| easedT = easingFunction(time); | |
| elem.scrollTop = (easedT * (Y - from)) + from; | |
| if(time < 1) requestAnimationFrame(scroll); | |
| else | |
| if(callback) callback(); | |
| } | |
| requestAnimationFrame(scroll); | |
| } | |
| function sglScrollmation(event) { | |
| var scroll_speed = 800, | |
| hash_value = event.target.attributes.href.value.substring(1), | |
| hash_section = document.getElementById(hash_value).offsetTop, | |
| ease_motion = easing.easeInOutCubic; | |
| scrollTo(hash_section, scroll_speed, ease_motion); | |
| } | |
| scrollmation_parent.addEventListener('click', sglScrollmation); |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment