LESS
body,html {height:100%;}
.movingcontent{
width: 100%;
height:100%;
overflow: hidden;
}
.movingcontent img{
opacity: 1;
transition: opacity .6s linear .8s;
}
.movingcontent img.loaded { opacity: 1; }
.img-pan-container, .img-pan-container img{ -webkit-box-sizing: border-box; -moz-box-sizing: border-box; box-sizing: border-box; }
.img-pan-container{
position: relative;
overflow: hidden;
height: 100%;
width: 100%;
}
.img-pan-container img{
-webkit-transform: translateZ(0); -ms-transform: translateZ(0); transform: translateZ(0);
position: absolute;
top: 0;
left: 0;
}
JAVASCRIPT
(function($){
$.fn.imagePanning=function(){
var init="center",
speed=800, //animation/tween speed
//custom js tween
_tweenTo=function(el,prop,to,duration,easing,overwrite){
if(!el._mTween){el._mTween={top:{},left:{}};}
var startTime=_getTime(),_delay,progress=0,from=el.offsetTop,elStyle=el.style,_request,tobj=el._mTween[prop];
if(prop==="left"){from=el.offsetLeft;}
var diff=to-from;
if(overwrite!=="none"){_cancelTween();}
_startTween();
function _step(){
progress=_getTime()-startTime;
_tween();
if(progress>=tobj.time){
tobj.time=(progress>tobj.time) ? progress+_delay-(progress-tobj.time) : progress+_delay-1;
if(tobj.time<progress+1){tobj.time=progress+1;}
}
if(tobj.time<duration){tobj.id=_request(_step);}
}
function _tween(){
if(duration>0){
tobj.currVal=_ease(tobj.time,from,diff,duration,easing);
elStyle[prop]=Math.round(tobj.currVal)+"px";
}else{
elStyle[prop]=to+"px";
}
}
function _startTween(){
_delay=1000/60;
tobj.time=progress+_delay;
_request=(!window.requestAnimationFrame) ? function(f){_tween(); return setTimeout(f,0.01);} : window.requestAnimationFrame;
tobj.id=_request(_step);
}
function _cancelTween(){
if(tobj.id==null){return;}
if(!window.requestAnimationFrame){clearTimeout(tobj.id);
}else{window.cancelAnimationFrame(tobj.id);}
tobj.id=null;
}
function _ease(t,b,c,d,type){
var ts=(t/=d)*t,tc=ts*t;
return b+c*(0.499999999999997*tc*ts + -2.5*ts*ts + 5.5*tc + -6.5*ts + 4*t);
}
function _getTime(){
if(window.performance && window.performance.now){
return window.performance.now();
}else{
if(window.performance && window.performance.webkitNow){
return window.performance.webkitNow();
}else{
if(Date.now){return Date.now();}else{return new Date().getTime();}
}
}
}
};
return this.each(function(){
var $this=$(this),timer,dest;
if($this.data("imagePanning")) return;
$this.data("imagePanning",1)
//create markup
.wrap("<div class='img-pan-container' />")
.after("<div class='resize' style='position:absolute; width:auto; height:auto; top:0; right:0; bottom:0; left:0; margin:0; padding:0; overflow:hidden; visibility:hidden; z-index:-1'><iframe style='width:100%; height:0; border:0; visibility:visible; margin:0' /><iframe style='width:0; height:100%; border:0; visibility:visible; margin:0' /></div>")
//image loaded fn
.one("load",function(){
setTimeout(function(){ $this.addClass("loaded").trigger("mousemove",1); },1);
}).each(function(){ //run load fn even if cached
if(this.complete) $(this).load();
})
//panning fn
.parent().on("mousemove touchmove MSPointerMove pointermove",function(e,p){
var cont=$(this);
e.preventDefault();
var contH=cont.height(),contW=cont.width(),
isTouch=e.type.indexOf("touch")!==-1,isPointer=e.type.indexOf("pointer")!==-1,
evt=isPointer ? e.originalEvent : isTouch ? e.originalEvent.touches[0] || e.originalEvent.changedTouches[0] : e,
coords=[
!p ? evt.pageY-cont.offset().top : init==="center" ? contH/2 : 0,
!p ? evt.pageX-cont.offset().left : init==="center" ? contW/2 : 0
];
dest=[Math.round(($this.outerHeight(true)-contH)*(coords[0]/contH)),Math.round(($this.outerWidth(true)-contW)*(coords[1]/contW))];
})
//resize fn
.find(".resize iframe").each(function(){
$(this.contentWindow || this).on("resize",function(){
$this.trigger("mousemove",1);
});
});
//panning animation 60FPS
if(timer) clearInterval(timer);
timer=setInterval(function(){
_tweenTo($this[0],"top",-dest[0],speed);
_tweenTo($this[0],"left",-dest[1],speed);
},16.6);
});
}
$(document).ready(function(){
$(".movingcontent img").imagePanning();
});
})(jQuery);
