policybot/fassets/js/components/image-changer.js

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JavaScript
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2021-11-30 10:56:55 +00:00
(function($){
$.fn.twentytwenty = function(options) {
var options = $.extend({default_offset_pct: 0.5, orientation: 'horizontal'}, options);
return this.each(function() {
var sliderPct = options.default_offset_pct;
var container = $(this);
var sliderOrientation = options.orientation;
var beforeDirection = (sliderOrientation === 'vertical') ? 'down' : 'left';
var afterDirection = (sliderOrientation === 'vertical') ? 'up' : 'right';
container.wrap("<div class='twentytwenty-wrapper twentytwenty-" + sliderOrientation + "'></div>");
container.append("<div class='twentytwenty-overlay'></div>");
var beforeImg = container.find("img:first");
var afterImg = container.find("img:last");
container.append("<div class='twentytwenty-handle'></div>");
var slider = container.find(".twentytwenty-handle");
slider.append("<span class='twentytwenty-" + beforeDirection + "-arrow'></span>");
slider.append("<span class='twentytwenty-" + afterDirection + "-arrow'></span>");
container.addClass("twentytwenty-container");
beforeImg.addClass("twentytwenty-before");
afterImg.addClass("twentytwenty-after");
var overlay = container.find(".twentytwenty-overlay");
overlay.append("<div class='twentytwenty-before-label'></div>");
overlay.append("<div class='twentytwenty-after-label'></div>");
var calcOffset = function(dimensionPct) {
var w = beforeImg.width();
var h = beforeImg.height();
return {
w: w+"px",
h: h+"px",
cw: (dimensionPct*w)+"px",
ch: (dimensionPct*h)+"px"
};
};
var adjustContainer = function(offset) {
if (sliderOrientation === 'vertical') {
beforeImg.css("clip", "rect(0,"+offset.w+","+offset.ch+",0)");
}
else {
beforeImg.css("clip", "rect(0,"+offset.cw+","+offset.h+",0)");
}
container.css("height", offset.h);
};
var adjustSlider = function(pct) {
var offset = calcOffset(pct);
slider.css((sliderOrientation==="vertical") ? "top" : "left", (sliderOrientation==="vertical") ? offset.ch : offset.cw);
adjustContainer(offset);
}
$(window).on("resize.twentytwenty", function(e) {
adjustSlider(sliderPct);
});
var offsetX = 0;
var imgWidth = 0;
slider.on("movestart", function(e) {
if (((e.distX > e.distY && e.distX < -e.distY) || (e.distX < e.distY && e.distX > -e.distY)) && sliderOrientation !== 'vertical') {
e.preventDefault();
}
else if (((e.distX < e.distY && e.distX < -e.distY) || (e.distX > e.distY && e.distX > -e.distY)) && sliderOrientation === 'vertical') {
e.preventDefault();
}
container.addClass("active");
offsetX = container.offset().left;
offsetY = container.offset().top;
imgWidth = beforeImg.width();
imgHeight = beforeImg.height();
});
slider.on("moveend", function(e) {
container.removeClass("active");
});
slider.on("move", function(e) {
if (container.hasClass("active")) {
sliderPct = (sliderOrientation === 'vertical') ? (e.pageY-offsetY)/imgHeight : (e.pageX-offsetX)/imgWidth;
if (sliderPct < 0) {
sliderPct = 0;
}
if (sliderPct > 1) {
sliderPct = 1;
}
adjustSlider(sliderPct);
}
});
container.find("img").on("mousedown", function(event) {
event.preventDefault();
});
$(window).trigger("resize.twentytwenty");
});
};
})(jQuery);