Joomla-Sermon-Distributor-Fork/media/uikit-v2/js/components/grid-parallax.js

169 lines
4.7 KiB
JavaScript

/*! UIkit 2.27.5 | http://www.getuikit.com | (c) 2014 YOOtheme | MIT License */
(function(addon) {
var component;
if (window.UIkit2) {
component = addon(UIkit2);
}
if (typeof define == 'function' && define.amd) {
define('uikit-grid-parallax', ['uikit'], function(){
return component || addon(UIkit2);
});
}
})(function(UI){
var parallaxes = [], checkParallaxes = function() {
requestAnimationFrame(function(){
for (var i=0; i < parallaxes.length; i++) {
parallaxes[i].process();
}
});
};
UI.component('gridparallax', {
defaults: {
target : false,
smooth : 150,
translate : 150
},
boot: function() {
// listen to scroll and resize
UI.$doc.on('scrolling.uk.document', checkParallaxes);
UI.$win.on('load resize orientationchange', UI.Utils.debounce(function(){
checkParallaxes();
}, 50));
// init code
UI.ready(function(context) {
UI.$('[data-uk-grid-parallax]', context).each(function() {
var parallax = UI.$(this);
if (!parallax.data('gridparallax')) {
UI.gridparallax(parallax, UI.Utils.options(parallax.attr('data-uk-grid-parallax')));
}
});
});
},
init: function() {
var $this = this;
this.initItems().process();
parallaxes.push(this);
UI.$win.on('load resize orientationchange', (function() {
var fn = function() {
var columns = getcolumns($this.element);
$this.element.css('margin-bottom', '');
if (columns > 1) {
$this.element.css('margin-bottom', $this.options.translate + parseInt($this.element.css('margin-bottom')));
}
};
UI.$(function() { fn(); });
return UI.Utils.debounce(fn, 50);
})());
},
initItems: function() {
var smooth = this.options.smooth;
this.items = (this.options.target ? this.element.find(this.options.target) : this.element.children()).each(function(){
UI.$(this).css({
transition: 'transform '+smooth+'ms linear',
transform: ''
});
});
return this;
},
process: function() {
var percent = percentageInViewport(this.element),
columns = getcolumns(this.element),
items = this.items,
mods = [(columns-1)];
if (columns == 1 || !percent) {
items.css('transform', '');
return;
}
while(mods.length < columns) {
if (!(mods[mods.length-1] - 2)) break;
mods.push(mods[mods.length-1] - 2);
}
var translate = this.options.translate, percenttranslate = percent * translate;
items.each(function(idx, ele, translate){
translate = mods.indexOf((idx+1) % columns) != -1 ? percenttranslate : percenttranslate / 8;
UI.$(this).css('transform', 'translate3d(0,'+(translate)+'px, 0)');
});
}
});
function getcolumns(element) {
var children = element.children(),
first = children.filter(':visible:first'),
top = first[0].offsetTop + first.outerHeight();
for (var column=0;column<children.length;column++) {
if (children[column].offsetTop >= top) break;
}
return column || 1;
}
function percentageInViewport(element) {
var top = element.offset().top,
height = element.outerHeight(),
scrolltop = UI.$win.scrollTop(),
wh = window.innerHeight,
distance, percentage, percent;
if (top > (scrolltop + wh)) {
percent = 0;
} else if ((top + height) < scrolltop) {
percent = 1;
} else {
if ((top + height) < wh) {
percent = (scrolltop < wh ? scrolltop : scrolltop - wh) / (top+height);
} else {
distance = (scrolltop + wh) - top;
percentage = Math.round(distance / ((wh + height) / 100));
percent = percentage/100;
}
if (top < wh) {
percent = percent * scrolltop / ((top + height) - wh);
}
}
return percent > 1 ? 1:percent;
}
});