| * @module RD SmoothScroll
|
| * @author Evgeniy Gusarov
|
| * @see https://ua.linkedin.com/pub/evgeniy-gusarov/8a/a40/54a
|
| !function(t,i,o){"use strict";var e="ontouchstart"in t,r=("undefined"!=typeof InstallTrigger,"MacIntel"===t.navigator.platform||"MacPPC"===t.navigator.platform),n="webkitTransform"in i.documentElement.style;t.requestAnimFrame=function(){return t.requestAnimationFrame||t.webkitRequestAnimationFrame||t.mozRequestAnimationFrame||t.oRequestAnimationFrame||t.msRequestAnimationFrame||function(i){t.setTimeout(i,1e3/60)}}(),t.RDSmoothScroll=function(){this.options=RDSmoothScroll.Defaults,this.animators=[],this.initialize()},RDSmoothScroll.Defaults={friction:.88,step:r? .65:2,minDistance:.1},RDSmoothScroll.Animator=function(t){var i="html"===t.nodeName.toLowerCase()&&n?t.children[t.children.length-1]:t;this.target=t,this.originalTarget=i,this.direction=o,this.currentY=i.scrollTop,this.targetY=i.scrollTop,this.lastY=i.scrollTop,this.delta=0,this.minY=0,this.maxY=o,this.isPlaying=!1,this.speed=0},RDSmoothScroll.Animator.prototype.update=function(i){var o=t.RDSmoothScroll.instance,e=i.detail?-1*i.detail:i.wheelDelta/40,r=0>e?-1:1;r!=this.direction&&(this.speed=0,this.direction=r),this.currentY=-this.originalTarget.scrollTop,this.delta=e,this.targetY+=e,this.speed+=(this.targetY-this.lastY)*o.options.step,this.lastY=this.targetY,this.start()},RDSmoothScroll.Animator.prototype.start=function(){this.isPlaying||(this.isPlaying=!0,t.jQuery&&t.jQuery(this.originalTarget).stop(),this.play())},RDSmoothScroll.Animator.prototype.play=function(){var t=this;this.isPlaying&&(requestAnimFrame(function(){t.play()}),this.render())},RDSmoothScroll.Animator.prototype.stop=function(){this.isPlaying&&(this.speed=0,this.isPlaying=!1)},RDSmoothScroll.Animator.prototype.render=function(){var i=t.RDSmoothScroll.instance;Math.abs(this.originalTarget.scrollTop- -this.currentY)>Math.abs(this.delta)&&Math.abs(this.originalTarget.scrollTop- -this.currentY)>1&&this.stop(),this.speed<-i.options.minDistance||this.speed>i.options.minDistance?(this.currentY=this.currentY+this.speed,this.currentY>this.minY?this.currentY=this.speed=0:this.currentY<this.maxY&&(this.speed=0,this.currentY=this.maxY),this.originalTarget.scrollTop=-this.currentY,this.speed*=i.options.friction):this.stop()},RDSmoothScroll.prototype.initialize=function(){t.addEventListener("mousewheel",this.onWheel),t.addEventListener("DOMMouseScroll",this.onWheel)},RDSmoothScroll.prototype.onWheel=function(i){if(!i.ctrlKey){var o,e,r=t.RDSmoothScroll.instance;for(i.preventDefault(),o=i.target;null!==o&&"html"!=o.nodeName.toLocaleLowerCase()&&!(("auto"==t.getComputedStyle(o).getPropertyValue("overflow")||"scroll"==t.getComputedStyle(o).getPropertyValue("overflow"))&&o.scrollHeight>o.clientHeight&&o.clientHeight>0);)o=o.parentNode;if(null!=o){e=r.isAnimator(o)?r.getAnimator(o):r.createAnimator(o);for(var n in r.animators)r.animators[n]!==e&&r.animators[n].stop&&r.animators[n].stop();e.update(i)}}},RDSmoothScroll.prototype.createAnimator=function(t){return this.animators[this.animators.push(new RDSmoothScroll.Animator(t))-1]},RDSmoothScroll.prototype.isAnimator=function(t){for(var i in this.animators)if(this.animators[i].target===t)return!0;return!1},RDSmoothScroll.prototype.getAnimator=function(t){for(var i in this.animators)if(this.animators[i].target===t)return this.animators[i];return o},e||(t.RDSmoothScroll.instance=new RDSmoothScroll)}(window,document); |
