upgrade to reveal.js-3.3.0
diff --git a/inst/reveal.js-3.3.0/js/reveal.js b/inst/reveal.js-3.3.0/js/reveal.js
new file mode 100644
index 0000000..7d9a305
--- /dev/null
+++ b/inst/reveal.js-3.3.0/js/reveal.js
@@ -0,0 +1,4744 @@
+/*!
+ * reveal.js
+ * http://lab.hakim.se/reveal-js
+ * MIT licensed
+ *
+ * Copyright (C) 2016 Hakim El Hattab, http://hakim.se
+ */
+(function( root, factory ) {
+ if( typeof define === 'function' && define.amd ) {
+ // AMD. Register as an anonymous module.
+ define( function() {
+ root.Reveal = factory();
+ return root.Reveal;
+ } );
+ } else if( typeof exports === 'object' ) {
+ // Node. Does not work with strict CommonJS.
+ module.exports = factory();
+ } else {
+ // Browser globals.
+ root.Reveal = factory();
+ }
+}( this, function() {
+
+ 'use strict';
+
+ var Reveal;
+
+ // The reveal.js version
+ var VERSION = '3.3.0';
+
+ var SLIDES_SELECTOR = '.slides section',
+ HORIZONTAL_SLIDES_SELECTOR = '.slides>section',
+ VERTICAL_SLIDES_SELECTOR = '.slides>section.present>section',
+ HOME_SLIDE_SELECTOR = '.slides>section:first-of-type',
+ UA = navigator.userAgent,
+
+ // Configuration defaults, can be overridden at initialization time
+ config = {
+
+ // The "normal" size of the presentation, aspect ratio will be preserved
+ // when the presentation is scaled to fit different resolutions
+ width: 960,
+ height: 700,
+
+ // Factor of the display size that should remain empty around the content
+ margin: 0.1,
+
+ // Bounds for smallest/largest possible scale to apply to content
+ minScale: 0.2,
+ maxScale: 1.5,
+
+ // Display controls in the bottom right corner
+ controls: true,
+
+ // Display a presentation progress bar
+ progress: true,
+
+ // Display the page number of the current slide
+ slideNumber: false,
+
+ // Push each slide change to the browser history
+ history: false,
+
+ // Enable keyboard shortcuts for navigation
+ keyboard: true,
+
+ // Optional function that blocks keyboard events when retuning false
+ keyboardCondition: null,
+
+ // Enable the slide overview mode
+ overview: true,
+
+ // Vertical centering of slides
+ center: true,
+
+ // Enables touch navigation on devices with touch input
+ touch: true,
+
+ // Loop the presentation
+ loop: false,
+
+ // Change the presentation direction to be RTL
+ rtl: false,
+
+ // Randomizes the order of slides each time the presentation loads
+ shuffle: false,
+
+ // Turns fragments on and off globally
+ fragments: true,
+
+ // Flags if the presentation is running in an embedded mode,
+ // i.e. contained within a limited portion of the screen
+ embedded: false,
+
+ // Flags if we should show a help overlay when the questionmark
+ // key is pressed
+ help: true,
+
+ // Flags if it should be possible to pause the presentation (blackout)
+ pause: true,
+
+ // Flags if speaker notes should be visible to all viewers
+ showNotes: false,
+
+ // Number of milliseconds between automatically proceeding to the
+ // next slide, disabled when set to 0, this value can be overwritten
+ // by using a data-autoslide attribute on your slides
+ autoSlide: 0,
+
+ // Stop auto-sliding after user input
+ autoSlideStoppable: true,
+
+ // Use this method for navigation when auto-sliding (defaults to navigateNext)
+ autoSlideMethod: null,
+
+ // Enable slide navigation via mouse wheel
+ mouseWheel: false,
+
+ // Apply a 3D roll to links on hover
+ rollingLinks: false,
+
+ // Hides the address bar on mobile devices
+ hideAddressBar: true,
+
+ // Opens links in an iframe preview overlay
+ previewLinks: false,
+
+ // Exposes the reveal.js API through window.postMessage
+ postMessage: true,
+
+ // Dispatches all reveal.js events to the parent window through postMessage
+ postMessageEvents: false,
+
+ // Focuses body when page changes visiblity to ensure keyboard shortcuts work
+ focusBodyOnPageVisibilityChange: true,
+
+ // Transition style
+ transition: 'slide', // none/fade/slide/convex/concave/zoom
+
+ // Transition speed
+ transitionSpeed: 'default', // default/fast/slow
+
+ // Transition style for full page slide backgrounds
+ backgroundTransition: 'fade', // none/fade/slide/convex/concave/zoom
+
+ // Parallax background image
+ parallaxBackgroundImage: '', // CSS syntax, e.g. "a.jpg"
+
+ // Parallax background size
+ parallaxBackgroundSize: '', // CSS syntax, e.g. "3000px 2000px"
+
+ // Amount of pixels to move the parallax background per slide step
+ parallaxBackgroundHorizontal: null,
+ parallaxBackgroundVertical: null,
+
+ // Number of slides away from the current that are visible
+ viewDistance: 3,
+
+ // Script dependencies to load
+ dependencies: []
+
+ },
+
+ // Flags if reveal.js is loaded (has dispatched the 'ready' event)
+ loaded = false,
+
+ // Flags if the overview mode is currently active
+ overview = false,
+
+ // Holds the dimensions of our overview slides, including margins
+ overviewSlideWidth = null,
+ overviewSlideHeight = null,
+
+ // The horizontal and vertical index of the currently active slide
+ indexh,
+ indexv,
+
+ // The previous and current slide HTML elements
+ previousSlide,
+ currentSlide,
+
+ previousBackground,
+
+ // Slides may hold a data-state attribute which we pick up and apply
+ // as a class to the body. This list contains the combined state of
+ // all current slides.
+ state = [],
+
+ // The current scale of the presentation (see width/height config)
+ scale = 1,
+
+ // CSS transform that is currently applied to the slides container,
+ // split into two groups
+ slidesTransform = { layout: '', overview: '' },
+
+ // Cached references to DOM elements
+ dom = {},
+
+ // Features supported by the browser, see #checkCapabilities()
+ features = {},
+
+ // Client is a mobile device, see #checkCapabilities()
+ isMobileDevice,
+
+ // Client is a desktop Chrome, see #checkCapabilities()
+ isChrome,
+
+ // Throttles mouse wheel navigation
+ lastMouseWheelStep = 0,
+
+ // Delays updates to the URL due to a Chrome thumbnailer bug
+ writeURLTimeout = 0,
+
+ // Flags if the interaction event listeners are bound
+ eventsAreBound = false,
+
+ // The current auto-slide duration
+ autoSlide = 0,
+
+ // Auto slide properties
+ autoSlidePlayer,
+ autoSlideTimeout = 0,
+ autoSlideStartTime = -1,
+ autoSlidePaused = false,
+
+ // Holds information about the currently ongoing touch input
+ touch = {
+ startX: 0,
+ startY: 0,
+ startSpan: 0,
+ startCount: 0,
+ captured: false,
+ threshold: 40
+ },
+
+ // Holds information about the keyboard shortcuts
+ keyboardShortcuts = {
+ 'N , SPACE': 'Next slide',
+ 'P': 'Previous slide',
+ '← , H': 'Navigate left',
+ '→ , L': 'Navigate right',
+ '↑ , K': 'Navigate up',
+ '↓ , J': 'Navigate down',
+ 'Home': 'First slide',
+ 'End': 'Last slide',
+ 'B , .': 'Pause',
+ 'F': 'Fullscreen',
+ 'ESC, O': 'Slide overview'
+ };
+
+ /**
+ * Starts up the presentation if the client is capable.
+ */
+ function initialize( options ) {
+
+ checkCapabilities();
+
+ if( !features.transforms2d && !features.transforms3d ) {
+ document.body.setAttribute( 'class', 'no-transforms' );
+
+ // Since JS won't be running any further, we load all lazy
+ // loading elements upfront
+ var images = toArray( document.getElementsByTagName( 'img' ) ),
+ iframes = toArray( document.getElementsByTagName( 'iframe' ) );
+
+ var lazyLoadable = images.concat( iframes );
+
+ for( var i = 0, len = lazyLoadable.length; i < len; i++ ) {
+ var element = lazyLoadable[i];
+ if( element.getAttribute( 'data-src' ) ) {
+ element.setAttribute( 'src', element.getAttribute( 'data-src' ) );
+ element.removeAttribute( 'data-src' );
+ }
+ }
+
+ // If the browser doesn't support core features we won't be
+ // using JavaScript to control the presentation
+ return;
+ }
+
+ // Cache references to key DOM elements
+ dom.wrapper = document.querySelector( '.reveal' );
+ dom.slides = document.querySelector( '.reveal .slides' );
+
+ // Force a layout when the whole page, incl fonts, has loaded
+ window.addEventListener( 'load', layout, false );
+
+ var query = Reveal.getQueryHash();
+
+ // Do not accept new dependencies via query config to avoid
+ // the potential of malicious script injection
+ if( typeof query['dependencies'] !== 'undefined' ) delete query['dependencies'];
+
+ // Copy options over to our config object
+ extend( config, options );
+ extend( config, query );
+
+ // Hide the address bar in mobile browsers
+ hideAddressBar();
+
+ // Loads the dependencies and continues to #start() once done
+ load();
+
+ }
+
+ /**
+ * Inspect the client to see what it's capable of, this
+ * should only happens once per runtime.
+ */
+ function checkCapabilities() {
+
+ isMobileDevice = /(iphone|ipod|ipad|android)/gi.test( UA );
+ isChrome = /chrome/i.test( UA ) && !/edge/i.test( UA );
+
+ var testElement = document.createElement( 'div' );
+
+ features.transforms3d = 'WebkitPerspective' in testElement.style ||
+ 'MozPerspective' in testElement.style ||
+ 'msPerspective' in testElement.style ||
+ 'OPerspective' in testElement.style ||
+ 'perspective' in testElement.style;
+
+ features.transforms2d = 'WebkitTransform' in testElement.style ||
+ 'MozTransform' in testElement.style ||
+ 'msTransform' in testElement.style ||
+ 'OTransform' in testElement.style ||
+ 'transform' in testElement.style;
+
+ features.requestAnimationFrameMethod = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame;
+ features.requestAnimationFrame = typeof features.requestAnimationFrameMethod === 'function';
+
+ features.canvas = !!document.createElement( 'canvas' ).getContext;
+
+ // Transitions in the overview are disabled in desktop and
+ // Safari due to lag
+ features.overviewTransitions = !/Version\/[\d\.]+.*Safari/.test( UA );
+
+ // Flags if we should use zoom instead of transform to scale
+ // up slides. Zoom produces crisper results but has a lot of
+ // xbrowser quirks so we only use it in whitelsited browsers.
+ features.zoom = 'zoom' in testElement.style && !isMobileDevice &&
+ ( isChrome || /Version\/[\d\.]+.*Safari/.test( UA ) );
+
+ }
+
+ /**
+ * Loads the dependencies of reveal.js. Dependencies are
+ * defined via the configuration option 'dependencies'
+ * and will be loaded prior to starting/binding reveal.js.
+ * Some dependencies may have an 'async' flag, if so they
+ * will load after reveal.js has been started up.
+ */
+ function load() {
+
+ var scripts = [],
+ scriptsAsync = [],
+ scriptsToPreload = 0;
+
+ // Called once synchronous scripts finish loading
+ function proceed() {
+ if( scriptsAsync.length ) {
+ // Load asynchronous scripts
+ head.js.apply( null, scriptsAsync );
+ }
+
+ start();
+ }
+
+ function loadScript( s ) {
+ head.ready( s.src.match( /([\w\d_\-]*)\.?js$|[^\\\/]*$/i )[0], function() {
+ // Extension may contain callback functions
+ if( typeof s.callback === 'function' ) {
+ s.callback.apply( this );
+ }
+
+ if( --scriptsToPreload === 0 ) {
+ proceed();
+ }
+ });
+ }
+
+ for( var i = 0, len = config.dependencies.length; i < len; i++ ) {
+ var s = config.dependencies[i];
+
+ // Load if there's no condition or the condition is truthy
+ if( !s.condition || s.condition() ) {
+ if( s.async ) {
+ scriptsAsync.push( s.src );
+ }
+ else {
+ scripts.push( s.src );
+ }
+
+ loadScript( s );
+ }
+ }
+
+ if( scripts.length ) {
+ scriptsToPreload = scripts.length;
+
+ // Load synchronous scripts
+ head.js.apply( null, scripts );
+ }
+ else {
+ proceed();
+ }
+
+ }
+
+ /**
+ * Starts up reveal.js by binding input events and navigating
+ * to the current URL deeplink if there is one.
+ */
+ function start() {
+
+ // Make sure we've got all the DOM elements we need
+ setupDOM();
+
+ // Listen to messages posted to this window
+ setupPostMessage();
+
+ // Prevent the slides from being scrolled out of view
+ setupScrollPrevention();
+
+ // Resets all vertical slides so that only the first is visible
+ resetVerticalSlides();
+
+ // Updates the presentation to match the current configuration values
+ configure();
+
+ // Read the initial hash
+ readURL();
+
+ // Update all backgrounds
+ updateBackground( true );
+
+ // Notify listeners that the presentation is ready but use a 1ms
+ // timeout to ensure it's not fired synchronously after #initialize()
+ setTimeout( function() {
+ // Enable transitions now that we're loaded
+ dom.slides.classList.remove( 'no-transition' );
+
+ loaded = true;
+
+ dispatchEvent( 'ready', {
+ 'indexh': indexh,
+ 'indexv': indexv,
+ 'currentSlide': currentSlide
+ } );
+ }, 1 );
+
+ // Special setup and config is required when printing to PDF
+ if( isPrintingPDF() ) {
+ removeEventListeners();
+
+ // The document needs to have loaded for the PDF layout
+ // measurements to be accurate
+ if( document.readyState === 'complete' ) {
+ setupPDF();
+ }
+ else {
+ window.addEventListener( 'load', setupPDF );
+ }
+ }
+
+ }
+
+ /**
+ * Finds and stores references to DOM elements which are
+ * required by the presentation. If a required element is
+ * not found, it is created.
+ */
+ function setupDOM() {
+
+ // Prevent transitions while we're loading
+ dom.slides.classList.add( 'no-transition' );
+
+ // Background element
+ dom.background = createSingletonNode( dom.wrapper, 'div', 'backgrounds', null );
+
+ // Progress bar
+ dom.progress = createSingletonNode( dom.wrapper, 'div', 'progress', '<span></span>' );
+ dom.progressbar = dom.progress.querySelector( 'span' );
+
+ // Arrow controls
+ createSingletonNode( dom.wrapper, 'aside', 'controls',
+ '<button class="navigate-left" aria-label="previous slide"></button>' +
+ '<button class="navigate-right" aria-label="next slide"></button>' +
+ '<button class="navigate-up" aria-label="above slide"></button>' +
+ '<button class="navigate-down" aria-label="below slide"></button>' );
+
+ // Slide number
+ dom.slideNumber = createSingletonNode( dom.wrapper, 'div', 'slide-number', '' );
+
+ // Element containing notes that are visible to the audience
+ dom.speakerNotes = createSingletonNode( dom.wrapper, 'div', 'speaker-notes', null );
+ dom.speakerNotes.setAttribute( 'data-prevent-swipe', '' );
+
+ // Overlay graphic which is displayed during the paused mode
+ createSingletonNode( dom.wrapper, 'div', 'pause-overlay', null );
+
+ // Cache references to elements
+ dom.controls = document.querySelector( '.reveal .controls' );
+ dom.theme = document.querySelector( '#theme' );
+
+ dom.wrapper.setAttribute( 'role', 'application' );
+
+ // There can be multiple instances of controls throughout the page
+ dom.controlsLeft = toArray( document.querySelectorAll( '.navigate-left' ) );
+ dom.controlsRight = toArray( document.querySelectorAll( '.navigate-right' ) );
+ dom.controlsUp = toArray( document.querySelectorAll( '.navigate-up' ) );
+ dom.controlsDown = toArray( document.querySelectorAll( '.navigate-down' ) );
+ dom.controlsPrev = toArray( document.querySelectorAll( '.navigate-prev' ) );
+ dom.controlsNext = toArray( document.querySelectorAll( '.navigate-next' ) );
+
+ dom.statusDiv = createStatusDiv();
+ }
+
+ /**
+ * Creates a hidden div with role aria-live to announce the
+ * current slide content. Hide the div off-screen to make it
+ * available only to Assistive Technologies.
+ */
+ function createStatusDiv() {
+
+ var statusDiv = document.getElementById( 'aria-status-div' );
+ if( !statusDiv ) {
+ statusDiv = document.createElement( 'div' );
+ statusDiv.style.position = 'absolute';
+ statusDiv.style.height = '1px';
+ statusDiv.style.width = '1px';
+ statusDiv.style.overflow ='hidden';
+ statusDiv.style.clip = 'rect( 1px, 1px, 1px, 1px )';
+ statusDiv.setAttribute( 'id', 'aria-status-div' );
+ statusDiv.setAttribute( 'aria-live', 'polite' );
+ statusDiv.setAttribute( 'aria-atomic','true' );
+ dom.wrapper.appendChild( statusDiv );
+ }
+ return statusDiv;
+
+ }
+
+ /**
+ * Configures the presentation for printing to a static
+ * PDF.
+ */
+ function setupPDF() {
+
+ var slideSize = getComputedSlideSize( window.innerWidth, window.innerHeight );
+
+ // Dimensions of the PDF pages
+ var pageWidth = Math.floor( slideSize.width * ( 1 + config.margin ) ),
+ pageHeight = Math.floor( slideSize.height * ( 1 + config.margin ) );
+
+ // Dimensions of slides within the pages
+ var slideWidth = slideSize.width,
+ slideHeight = slideSize.height;
+
+ // Let the browser know what page size we want to print
+ injectStyleSheet( '@page{size:'+ pageWidth +'px '+ pageHeight +'px; margin: 0;}' );
+
+ // Limit the size of certain elements to the dimensions of the slide
+ injectStyleSheet( '.reveal section>img, .reveal section>video, .reveal section>iframe{max-width: '+ slideWidth +'px; max-height:'+ slideHeight +'px}' );
+
+ document.body.classList.add( 'print-pdf' );
+ document.body.style.width = pageWidth + 'px';
+ document.body.style.height = pageHeight + 'px';
+
+ // Add each slide's index as attributes on itself, we need these
+ // indices to generate slide numbers below
+ toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).forEach( function( hslide, h ) {
+ hslide.setAttribute( 'data-index-h', h );
+
+ if( hslide.classList.contains( 'stack' ) ) {
+ toArray( hslide.querySelectorAll( 'section' ) ).forEach( function( vslide, v ) {
+ vslide.setAttribute( 'data-index-h', h );
+ vslide.setAttribute( 'data-index-v', v );
+ } );
+ }
+ } );
+
+ // Slide and slide background layout
+ toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) ).forEach( function( slide ) {
+
+ // Vertical stacks are not centred since their section
+ // children will be
+ if( slide.classList.contains( 'stack' ) === false ) {
+ // Center the slide inside of the page, giving the slide some margin
+ var left = ( pageWidth - slideWidth ) / 2,
+ top = ( pageHeight - slideHeight ) / 2;
+
+ var contentHeight = getAbsoluteHeight( slide );
+ var numberOfPages = Math.max( Math.ceil( contentHeight / pageHeight ), 1 );
+
+ // Center slides vertically
+ if( numberOfPages === 1 && config.center || slide.classList.contains( 'center' ) ) {
+ top = Math.max( ( pageHeight - contentHeight ) / 2, 0 );
+ }
+
+ // Position the slide inside of the page
+ slide.style.left = left + 'px';
+ slide.style.top = top + 'px';
+ slide.style.width = slideWidth + 'px';
+
+ // TODO Backgrounds need to be multiplied when the slide
+ // stretches over multiple pages
+ var background = slide.querySelector( '.slide-background' );
+ if( background ) {
+ background.style.width = pageWidth + 'px';
+ background.style.height = ( pageHeight * numberOfPages ) + 'px';
+ background.style.top = -top + 'px';
+ background.style.left = -left + 'px';
+ }
+
+ // Inject notes if `showNotes` is enabled
+ if( config.showNotes ) {
+ var notes = getSlideNotes( slide );
+ if( notes ) {
+ var notesSpacing = 8;
+ var notesElement = document.createElement( 'div' );
+ notesElement.classList.add( 'speaker-notes' );
+ notesElement.classList.add( 'speaker-notes-pdf' );
+ notesElement.innerHTML = notes;
+ notesElement.style.left = ( notesSpacing - left ) + 'px';
+ notesElement.style.bottom = ( notesSpacing - top ) + 'px';
+ notesElement.style.width = ( pageWidth - notesSpacing*2 ) + 'px';
+ slide.appendChild( notesElement );
+ }
+ }
+
+ // Inject slide numbers if `slideNumbers` are enabled
+ if( config.slideNumber ) {
+ var slideNumberH = parseInt( slide.getAttribute( 'data-index-h' ), 10 ) + 1,
+ slideNumberV = parseInt( slide.getAttribute( 'data-index-v' ), 10 ) + 1;
+
+ var numberElement = document.createElement( 'div' );
+ numberElement.classList.add( 'slide-number' );
+ numberElement.classList.add( 'slide-number-pdf' );
+ numberElement.innerHTML = formatSlideNumber( slideNumberH, '.', slideNumberV );
+ background.appendChild( numberElement );
+ }
+ }
+
+ } );
+
+ // Show all fragments
+ toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR + ' .fragment' ) ).forEach( function( fragment ) {
+ fragment.classList.add( 'visible' );
+ } );
+
+ }
+
+ /**
+ * This is an unfortunate necessity. Some actions – such as
+ * an input field being focused in an iframe or using the
+ * keyboard to expand text selection beyond the bounds of
+ * a slide – can trigger our content to be pushed out of view.
+ * This scrolling can not be prevented by hiding overflow in
+ * CSS (we already do) so we have to resort to repeatedly
+ * checking if the slides have been offset :(
+ */
+ function setupScrollPrevention() {
+
+ setInterval( function() {
+ if( dom.wrapper.scrollTop !== 0 || dom.wrapper.scrollLeft !== 0 ) {
+ dom.wrapper.scrollTop = 0;
+ dom.wrapper.scrollLeft = 0;
+ }
+ }, 1000 );
+
+ }
+
+ /**
+ * Creates an HTML element and returns a reference to it.
+ * If the element already exists the existing instance will
+ * be returned.
+ */
+ function createSingletonNode( container, tagname, classname, innerHTML ) {
+
+ // Find all nodes matching the description
+ var nodes = container.querySelectorAll( '.' + classname );
+
+ // Check all matches to find one which is a direct child of
+ // the specified container
+ for( var i = 0; i < nodes.length; i++ ) {
+ var testNode = nodes[i];
+ if( testNode.parentNode === container ) {
+ return testNode;
+ }
+ }
+
+ // If no node was found, create it now
+ var node = document.createElement( tagname );
+ node.classList.add( classname );
+ if( typeof innerHTML === 'string' ) {
+ node.innerHTML = innerHTML;
+ }
+ container.appendChild( node );
+
+ return node;
+
+ }
+
+ /**
+ * Creates the slide background elements and appends them
+ * to the background container. One element is created per
+ * slide no matter if the given slide has visible background.
+ */
+ function createBackgrounds() {
+
+ var printMode = isPrintingPDF();
+
+ // Clear prior backgrounds
+ dom.background.innerHTML = '';
+ dom.background.classList.add( 'no-transition' );
+
+ // Iterate over all horizontal slides
+ toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).forEach( function( slideh ) {
+
+ var backgroundStack;
+
+ if( printMode ) {
+ backgroundStack = createBackground( slideh, slideh );
+ }
+ else {
+ backgroundStack = createBackground( slideh, dom.background );
+ }
+
+ // Iterate over all vertical slides
+ toArray( slideh.querySelectorAll( 'section' ) ).forEach( function( slidev ) {
+
+ if( printMode ) {
+ createBackground( slidev, slidev );
+ }
+ else {
+ createBackground( slidev, backgroundStack );
+ }
+
+ backgroundStack.classList.add( 'stack' );
+
+ } );
+
+ } );
+
+ // Add parallax background if specified
+ if( config.parallaxBackgroundImage ) {
+
+ dom.background.style.backgroundImage = 'url("' + config.parallaxBackgroundImage + '")';
+ dom.background.style.backgroundSize = config.parallaxBackgroundSize;
+
+ // Make sure the below properties are set on the element - these properties are
+ // needed for proper transitions to be set on the element via CSS. To remove
+ // annoying background slide-in effect when the presentation starts, apply
+ // these properties after short time delay
+ setTimeout( function() {
+ dom.wrapper.classList.add( 'has-parallax-background' );
+ }, 1 );
+
+ }
+ else {
+
+ dom.background.style.backgroundImage = '';
+ dom.wrapper.classList.remove( 'has-parallax-background' );
+
+ }
+
+ }
+
+ /**
+ * Creates a background for the given slide.
+ *
+ * @param {HTMLElement} slide
+ * @param {HTMLElement} container The element that the background
+ * should be appended to
+ */
+ function createBackground( slide, container ) {
+
+ var data = {
+ background: slide.getAttribute( 'data-background' ),
+ backgroundSize: slide.getAttribute( 'data-background-size' ),
+ backgroundImage: slide.getAttribute( 'data-background-image' ),
+ backgroundVideo: slide.getAttribute( 'data-background-video' ),
+ backgroundIframe: slide.getAttribute( 'data-background-iframe' ),
+ backgroundColor: slide.getAttribute( 'data-background-color' ),
+ backgroundRepeat: slide.getAttribute( 'data-background-repeat' ),
+ backgroundPosition: slide.getAttribute( 'data-background-position' ),
+ backgroundTransition: slide.getAttribute( 'data-background-transition' )
+ };
+
+ var element = document.createElement( 'div' );
+
+ // Carry over custom classes from the slide to the background
+ element.className = 'slide-background ' + slide.className.replace( /present|past|future/, '' );
+
+ if( data.background ) {
+ // Auto-wrap image urls in url(...)
+ if( /^(http|file|\/\/)/gi.test( data.background ) || /\.(svg|png|jpg|jpeg|gif|bmp)$/gi.test( data.background ) ) {
+ slide.setAttribute( 'data-background-image', data.background );
+ }
+ else {
+ element.style.background = data.background;
+ }
+ }
+
+ // Create a hash for this combination of background settings.
+ // This is used to determine when two slide backgrounds are
+ // the same.
+ if( data.background || data.backgroundColor || data.backgroundImage || data.backgroundVideo || data.backgroundIframe ) {
+ element.setAttribute( 'data-background-hash', data.background +
+ data.backgroundSize +
+ data.backgroundImage +
+ data.backgroundVideo +
+ data.backgroundIframe +
+ data.backgroundColor +
+ data.backgroundRepeat +
+ data.backgroundPosition +
+ data.backgroundTransition );
+ }
+
+ // Additional and optional background properties
+ if( data.backgroundSize ) element.style.backgroundSize = data.backgroundSize;
+ if( data.backgroundColor ) element.style.backgroundColor = data.backgroundColor;
+ if( data.backgroundRepeat ) element.style.backgroundRepeat = data.backgroundRepeat;
+ if( data.backgroundPosition ) element.style.backgroundPosition = data.backgroundPosition;
+ if( data.backgroundTransition ) element.setAttribute( 'data-background-transition', data.backgroundTransition );
+
+ container.appendChild( element );
+
+ // If backgrounds are being recreated, clear old classes
+ slide.classList.remove( 'has-dark-background' );
+ slide.classList.remove( 'has-light-background' );
+
+ // If this slide has a background color, add a class that
+ // signals if it is light or dark. If the slide has no background
+ // color, no class will be set
+ var computedBackgroundColor = window.getComputedStyle( element ).backgroundColor;
+ if( computedBackgroundColor ) {
+ var rgb = colorToRgb( computedBackgroundColor );
+
+ // Ignore fully transparent backgrounds. Some browsers return
+ // rgba(0,0,0,0) when reading the computed background color of
+ // an element with no background
+ if( rgb && rgb.a !== 0 ) {
+ if( colorBrightness( computedBackgroundColor ) < 128 ) {
+ slide.classList.add( 'has-dark-background' );
+ }
+ else {
+ slide.classList.add( 'has-light-background' );
+ }
+ }
+ }
+
+ return element;
+
+ }
+
+ /**
+ * Registers a listener to postMessage events, this makes it
+ * possible to call all reveal.js API methods from another
+ * window. For example:
+ *
+ * revealWindow.postMessage( JSON.stringify({
+ * method: 'slide',
+ * args: [ 2 ]
+ * }), '*' );
+ */
+ function setupPostMessage() {
+
+ if( config.postMessage ) {
+ window.addEventListener( 'message', function ( event ) {
+ var data = event.data;
+
+ // Make sure we're dealing with JSON
+ if( typeof data === 'string' && data.charAt( 0 ) === '{' && data.charAt( data.length - 1 ) === '}' ) {
+ data = JSON.parse( data );
+
+ // Check if the requested method can be found
+ if( data.method && typeof Reveal[data.method] === 'function' ) {
+ Reveal[data.method].apply( Reveal, data.args );
+ }
+ }
+ }, false );
+ }
+
+ }
+
+ /**
+ * Applies the configuration settings from the config
+ * object. May be called multiple times.
+ */
+ function configure( options ) {
+
+ var numberOfSlides = dom.wrapper.querySelectorAll( SLIDES_SELECTOR ).length;
+
+ dom.wrapper.classList.remove( config.transition );
+
+ // New config options may be passed when this method
+ // is invoked through the API after initialization
+ if( typeof options === 'object' ) extend( config, options );
+
+ // Force linear transition based on browser capabilities
+ if( features.transforms3d === false ) config.transition = 'linear';
+
+ dom.wrapper.classList.add( config.transition );
+
+ dom.wrapper.setAttribute( 'data-transition-speed', config.transitionSpeed );
+ dom.wrapper.setAttribute( 'data-background-transition', config.backgroundTransition );
+
+ dom.controls.style.display = config.controls ? 'block' : 'none';
+ dom.progress.style.display = config.progress ? 'block' : 'none';
+ dom.slideNumber.style.display = config.slideNumber && !isPrintingPDF() ? 'block' : 'none';
+
+ if( config.shuffle ) {
+ shuffle();
+ }
+
+ if( config.rtl ) {
+ dom.wrapper.classList.add( 'rtl' );
+ }
+ else {
+ dom.wrapper.classList.remove( 'rtl' );
+ }
+
+ if( config.center ) {
+ dom.wrapper.classList.add( 'center' );
+ }
+ else {
+ dom.wrapper.classList.remove( 'center' );
+ }
+
+ // Exit the paused mode if it was configured off
+ if( config.pause === false ) {
+ resume();
+ }
+
+ if( config.showNotes ) {
+ dom.speakerNotes.classList.add( 'visible' );
+ }
+ else {
+ dom.speakerNotes.classList.remove( 'visible' );
+ }
+
+ if( config.mouseWheel ) {
+ document.addEventListener( 'DOMMouseScroll', onDocumentMouseScroll, false ); // FF
+ document.addEventListener( 'mousewheel', onDocumentMouseScroll, false );
+ }
+ else {
+ document.removeEventListener( 'DOMMouseScroll', onDocumentMouseScroll, false ); // FF
+ document.removeEventListener( 'mousewheel', onDocumentMouseScroll, false );
+ }
+
+ // Rolling 3D links
+ if( config.rollingLinks ) {
+ enableRollingLinks();
+ }
+ else {
+ disableRollingLinks();
+ }
+
+ // Iframe link previews
+ if( config.previewLinks ) {
+ enablePreviewLinks();
+ }
+ else {
+ disablePreviewLinks();
+ enablePreviewLinks( '[data-preview-link]' );
+ }
+
+ // Remove existing auto-slide controls
+ if( autoSlidePlayer ) {
+ autoSlidePlayer.destroy();
+ autoSlidePlayer = null;
+ }
+
+ // Generate auto-slide controls if needed
+ if( numberOfSlides > 1 && config.autoSlide && config.autoSlideStoppable && features.canvas && features.requestAnimationFrame ) {
+ autoSlidePlayer = new Playback( dom.wrapper, function() {
+ return Math.min( Math.max( ( Date.now() - autoSlideStartTime ) / autoSlide, 0 ), 1 );
+ } );
+
+ autoSlidePlayer.on( 'click', onAutoSlidePlayerClick );
+ autoSlidePaused = false;
+ }
+
+ // When fragments are turned off they should be visible
+ if( config.fragments === false ) {
+ toArray( dom.slides.querySelectorAll( '.fragment' ) ).forEach( function( element ) {
+ element.classList.add( 'visible' );
+ element.classList.remove( 'current-fragment' );
+ } );
+ }
+
+ sync();
+
+ }
+
+ /**
+ * Binds all event listeners.
+ */
+ function addEventListeners() {
+
+ eventsAreBound = true;
+
+ window.addEventListener( 'hashchange', onWindowHashChange, false );
+ window.addEventListener( 'resize', onWindowResize, false );
+
+ if( config.touch ) {
+ dom.wrapper.addEventListener( 'touchstart', onTouchStart, false );
+ dom.wrapper.addEventListener( 'touchmove', onTouchMove, false );
+ dom.wrapper.addEventListener( 'touchend', onTouchEnd, false );
+
+ // Support pointer-style touch interaction as well
+ if( window.navigator.pointerEnabled ) {
+ // IE 11 uses un-prefixed version of pointer events
+ dom.wrapper.addEventListener( 'pointerdown', onPointerDown, false );
+ dom.wrapper.addEventListener( 'pointermove', onPointerMove, false );
+ dom.wrapper.addEventListener( 'pointerup', onPointerUp, false );
+ }
+ else if( window.navigator.msPointerEnabled ) {
+ // IE 10 uses prefixed version of pointer events
+ dom.wrapper.addEventListener( 'MSPointerDown', onPointerDown, false );
+ dom.wrapper.addEventListener( 'MSPointerMove', onPointerMove, false );
+ dom.wrapper.addEventListener( 'MSPointerUp', onPointerUp, false );
+ }
+ }
+
+ if( config.keyboard ) {
+ document.addEventListener( 'keydown', onDocumentKeyDown, false );
+ document.addEventListener( 'keypress', onDocumentKeyPress, false );
+ }
+
+ if( config.progress && dom.progress ) {
+ dom.progress.addEventListener( 'click', onProgressClicked, false );
+ }
+
+ if( config.focusBodyOnPageVisibilityChange ) {
+ var visibilityChange;
+
+ if( 'hidden' in document ) {
+ visibilityChange = 'visibilitychange';
+ }
+ else if( 'msHidden' in document ) {
+ visibilityChange = 'msvisibilitychange';
+ }
+ else if( 'webkitHidden' in document ) {
+ visibilityChange = 'webkitvisibilitychange';
+ }
+
+ if( visibilityChange ) {
+ document.addEventListener( visibilityChange, onPageVisibilityChange, false );
+ }
+ }
+
+ // Listen to both touch and click events, in case the device
+ // supports both
+ var pointerEvents = [ 'touchstart', 'click' ];
+
+ // Only support touch for Android, fixes double navigations in
+ // stock browser
+ if( UA.match( /android/gi ) ) {
+ pointerEvents = [ 'touchstart' ];
+ }
+
+ pointerEvents.forEach( function( eventName ) {
+ dom.controlsLeft.forEach( function( el ) { el.addEventListener( eventName, onNavigateLeftClicked, false ); } );
+ dom.controlsRight.forEach( function( el ) { el.addEventListener( eventName, onNavigateRightClicked, false ); } );
+ dom.controlsUp.forEach( function( el ) { el.addEventListener( eventName, onNavigateUpClicked, false ); } );
+ dom.controlsDown.forEach( function( el ) { el.addEventListener( eventName, onNavigateDownClicked, false ); } );
+ dom.controlsPrev.forEach( function( el ) { el.addEventListener( eventName, onNavigatePrevClicked, false ); } );
+ dom.controlsNext.forEach( function( el ) { el.addEventListener( eventName, onNavigateNextClicked, false ); } );
+ } );
+
+ }
+
+ /**
+ * Unbinds all event listeners.
+ */
+ function removeEventListeners() {
+
+ eventsAreBound = false;
+
+ document.removeEventListener( 'keydown', onDocumentKeyDown, false );
+ document.removeEventListener( 'keypress', onDocumentKeyPress, false );
+ window.removeEventListener( 'hashchange', onWindowHashChange, false );
+ window.removeEventListener( 'resize', onWindowResize, false );
+
+ dom.wrapper.removeEventListener( 'touchstart', onTouchStart, false );
+ dom.wrapper.removeEventListener( 'touchmove', onTouchMove, false );
+ dom.wrapper.removeEventListener( 'touchend', onTouchEnd, false );
+
+ // IE11
+ if( window.navigator.pointerEnabled ) {
+ dom.wrapper.removeEventListener( 'pointerdown', onPointerDown, false );
+ dom.wrapper.removeEventListener( 'pointermove', onPointerMove, false );
+ dom.wrapper.removeEventListener( 'pointerup', onPointerUp, false );
+ }
+ // IE10
+ else if( window.navigator.msPointerEnabled ) {
+ dom.wrapper.removeEventListener( 'MSPointerDown', onPointerDown, false );
+ dom.wrapper.removeEventListener( 'MSPointerMove', onPointerMove, false );
+ dom.wrapper.removeEventListener( 'MSPointerUp', onPointerUp, false );
+ }
+
+ if ( config.progress && dom.progress ) {
+ dom.progress.removeEventListener( 'click', onProgressClicked, false );
+ }
+
+ [ 'touchstart', 'click' ].forEach( function( eventName ) {
+ dom.controlsLeft.forEach( function( el ) { el.removeEventListener( eventName, onNavigateLeftClicked, false ); } );
+ dom.controlsRight.forEach( function( el ) { el.removeEventListener( eventName, onNavigateRightClicked, false ); } );
+ dom.controlsUp.forEach( function( el ) { el.removeEventListener( eventName, onNavigateUpClicked, false ); } );
+ dom.controlsDown.forEach( function( el ) { el.removeEventListener( eventName, onNavigateDownClicked, false ); } );
+ dom.controlsPrev.forEach( function( el ) { el.removeEventListener( eventName, onNavigatePrevClicked, false ); } );
+ dom.controlsNext.forEach( function( el ) { el.removeEventListener( eventName, onNavigateNextClicked, false ); } );
+ } );
+
+ }
+
+ /**
+ * Extend object a with the properties of object b.
+ * If there's a conflict, object b takes precedence.
+ */
+ function extend( a, b ) {
+
+ for( var i in b ) {
+ a[ i ] = b[ i ];
+ }
+
+ }
+
+ /**
+ * Converts the target object to an array.
+ */
+ function toArray( o ) {
+
+ return Array.prototype.slice.call( o );
+
+ }
+
+ /**
+ * Utility for deserializing a value.
+ */
+ function deserialize( value ) {
+
+ if( typeof value === 'string' ) {
+ if( value === 'null' ) return null;
+ else if( value === 'true' ) return true;
+ else if( value === 'false' ) return false;
+ else if( value.match( /^\d+$/ ) ) return parseFloat( value );
+ }
+
+ return value;
+
+ }
+
+ /**
+ * Measures the distance in pixels between point a
+ * and point b.
+ *
+ * @param {Object} a point with x/y properties
+ * @param {Object} b point with x/y properties
+ */
+ function distanceBetween( a, b ) {
+
+ var dx = a.x - b.x,
+ dy = a.y - b.y;
+
+ return Math.sqrt( dx*dx + dy*dy );
+
+ }
+
+ /**
+ * Applies a CSS transform to the target element.
+ */
+ function transformElement( element, transform ) {
+
+ element.style.WebkitTransform = transform;
+ element.style.MozTransform = transform;
+ element.style.msTransform = transform;
+ element.style.transform = transform;
+
+ }
+
+ /**
+ * Applies CSS transforms to the slides container. The container
+ * is transformed from two separate sources: layout and the overview
+ * mode.
+ */
+ function transformSlides( transforms ) {
+
+ // Pick up new transforms from arguments
+ if( typeof transforms.layout === 'string' ) slidesTransform.layout = transforms.layout;
+ if( typeof transforms.overview === 'string' ) slidesTransform.overview = transforms.overview;
+
+ // Apply the transforms to the slides container
+ if( slidesTransform.layout ) {
+ transformElement( dom.slides, slidesTransform.layout + ' ' + slidesTransform.overview );
+ }
+ else {
+ transformElement( dom.slides, slidesTransform.overview );
+ }
+
+ }
+
+ /**
+ * Injects the given CSS styles into the DOM.
+ */
+ function injectStyleSheet( value ) {
+
+ var tag = document.createElement( 'style' );
+ tag.type = 'text/css';
+ if( tag.styleSheet ) {
+ tag.styleSheet.cssText = value;
+ }
+ else {
+ tag.appendChild( document.createTextNode( value ) );
+ }
+ document.getElementsByTagName( 'head' )[0].appendChild( tag );
+
+ }
+
+ /**
+ * Converts various color input formats to an {r:0,g:0,b:0} object.
+ *
+ * @param {String} color The string representation of a color,
+ * the following formats are supported:
+ * - #000
+ * - #000000
+ * - rgb(0,0,0)
+ */
+ function colorToRgb( color ) {
+
+ var hex3 = color.match( /^#([0-9a-f]{3})$/i );
+ if( hex3 && hex3[1] ) {
+ hex3 = hex3[1];
+ return {
+ r: parseInt( hex3.charAt( 0 ), 16 ) * 0x11,
+ g: parseInt( hex3.charAt( 1 ), 16 ) * 0x11,
+ b: parseInt( hex3.charAt( 2 ), 16 ) * 0x11
+ };
+ }
+
+ var hex6 = color.match( /^#([0-9a-f]{6})$/i );
+ if( hex6 && hex6[1] ) {
+ hex6 = hex6[1];
+ return {
+ r: parseInt( hex6.substr( 0, 2 ), 16 ),
+ g: parseInt( hex6.substr( 2, 2 ), 16 ),
+ b: parseInt( hex6.substr( 4, 2 ), 16 )
+ };
+ }
+
+ var rgb = color.match( /^rgb\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$/i );
+ if( rgb ) {
+ return {
+ r: parseInt( rgb[1], 10 ),
+ g: parseInt( rgb[2], 10 ),
+ b: parseInt( rgb[3], 10 )
+ };
+ }
+
+ var rgba = color.match( /^rgba\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\,\s*([\d]+|[\d]*.[\d]+)\s*\)$/i );
+ if( rgba ) {
+ return {
+ r: parseInt( rgba[1], 10 ),
+ g: parseInt( rgba[2], 10 ),
+ b: parseInt( rgba[3], 10 ),
+ a: parseFloat( rgba[4] )
+ };
+ }
+
+ return null;
+
+ }
+
+ /**
+ * Calculates brightness on a scale of 0-255.
+ *
+ * @param color See colorStringToRgb for supported formats.
+ */
+ function colorBrightness( color ) {
+
+ if( typeof color === 'string' ) color = colorToRgb( color );
+
+ if( color ) {
+ return ( color.r * 299 + color.g * 587 + color.b * 114 ) / 1000;
+ }
+
+ return null;
+
+ }
+
+ /**
+ * Retrieves the height of the given element by looking
+ * at the position and height of its immediate children.
+ */
+ function getAbsoluteHeight( element ) {
+
+ var height = 0;
+
+ if( element ) {
+ var absoluteChildren = 0;
+
+ toArray( element.childNodes ).forEach( function( child ) {
+
+ if( typeof child.offsetTop === 'number' && child.style ) {
+ // Count # of abs children
+ if( window.getComputedStyle( child ).position === 'absolute' ) {
+ absoluteChildren += 1;
+ }
+
+ height = Math.max( height, child.offsetTop + child.offsetHeight );
+ }
+
+ } );
+
+ // If there are no absolute children, use offsetHeight
+ if( absoluteChildren === 0 ) {
+ height = element.offsetHeight;
+ }
+
+ }
+
+ return height;
+
+ }
+
+ /**
+ * Returns the remaining height within the parent of the
+ * target element.
+ *
+ * remaining height = [ configured parent height ] - [ current parent height ]
+ */
+ function getRemainingHeight( element, height ) {
+
+ height = height || 0;
+
+ if( element ) {
+ var newHeight, oldHeight = element.style.height;
+
+ // Change the .stretch element height to 0 in order find the height of all
+ // the other elements
+ element.style.height = '0px';
+ newHeight = height - element.parentNode.offsetHeight;
+
+ // Restore the old height, just in case
+ element.style.height = oldHeight + 'px';
+
+ return newHeight;
+ }
+
+ return height;
+
+ }
+
+ /**
+ * Checks if this instance is being used to print a PDF.
+ */
+ function isPrintingPDF() {
+
+ return ( /print-pdf/gi ).test( window.location.search );
+
+ }
+
+ /**
+ * Hides the address bar if we're on a mobile device.
+ */
+ function hideAddressBar() {
+
+ if( config.hideAddressBar && isMobileDevice ) {
+ // Events that should trigger the address bar to hide
+ window.addEventListener( 'load', removeAddressBar, false );
+ window.addEventListener( 'orientationchange', removeAddressBar, false );
+ }
+
+ }
+
+ /**
+ * Causes the address bar to hide on mobile devices,
+ * more vertical space ftw.
+ */
+ function removeAddressBar() {
+
+ setTimeout( function() {
+ window.scrollTo( 0, 1 );
+ }, 10 );
+
+ }
+
+ /**
+ * Dispatches an event of the specified type from the
+ * reveal DOM element.
+ */
+ function dispatchEvent( type, args ) {
+
+ var event = document.createEvent( 'HTMLEvents', 1, 2 );
+ event.initEvent( type, true, true );
+ extend( event, args );
+ dom.wrapper.dispatchEvent( event );
+
+ // If we're in an iframe, post each reveal.js event to the
+ // parent window. Used by the notes plugin
+ if( config.postMessageEvents && window.parent !== window.self ) {
+ window.parent.postMessage( JSON.stringify({ namespace: 'reveal', eventName: type, state: getState() }), '*' );
+ }
+
+ }
+
+ /**
+ * Wrap all links in 3D goodness.
+ */
+ function enableRollingLinks() {
+
+ if( features.transforms3d && !( 'msPerspective' in document.body.style ) ) {
+ var anchors = dom.wrapper.querySelectorAll( SLIDES_SELECTOR + ' a' );
+
+ for( var i = 0, len = anchors.length; i < len; i++ ) {
+ var anchor = anchors[i];
+
+ if( anchor.textContent && !anchor.querySelector( '*' ) && ( !anchor.className || !anchor.classList.contains( anchor, 'roll' ) ) ) {
+ var span = document.createElement('span');
+ span.setAttribute('data-title', anchor.text);
+ span.innerHTML = anchor.innerHTML;
+
+ anchor.classList.add( 'roll' );
+ anchor.innerHTML = '';
+ anchor.appendChild(span);
+ }
+ }
+ }
+
+ }
+
+ /**
+ * Unwrap all 3D links.
+ */
+ function disableRollingLinks() {
+
+ var anchors = dom.wrapper.querySelectorAll( SLIDES_SELECTOR + ' a.roll' );
+
+ for( var i = 0, len = anchors.length; i < len; i++ ) {
+ var anchor = anchors[i];
+ var span = anchor.querySelector( 'span' );
+
+ if( span ) {
+ anchor.classList.remove( 'roll' );
+ anchor.innerHTML = span.innerHTML;
+ }
+ }
+
+ }
+
+ /**
+ * Bind preview frame links.
+ */
+ function enablePreviewLinks( selector ) {
+
+ var anchors = toArray( document.querySelectorAll( selector ? selector : 'a' ) );
+
+ anchors.forEach( function( element ) {
+ if( /^(http|www)/gi.test( element.getAttribute( 'href' ) ) ) {
+ element.addEventListener( 'click', onPreviewLinkClicked, false );
+ }
+ } );
+
+ }
+
+ /**
+ * Unbind preview frame links.
+ */
+ function disablePreviewLinks() {
+
+ var anchors = toArray( document.querySelectorAll( 'a' ) );
+
+ anchors.forEach( function( element ) {
+ if( /^(http|www)/gi.test( element.getAttribute( 'href' ) ) ) {
+ element.removeEventListener( 'click', onPreviewLinkClicked, false );
+ }
+ } );
+
+ }
+
+ /**
+ * Opens a preview window for the target URL.
+ */
+ function showPreview( url ) {
+
+ closeOverlay();
+
+ dom.overlay = document.createElement( 'div' );
+ dom.overlay.classList.add( 'overlay' );
+ dom.overlay.classList.add( 'overlay-preview' );
+ dom.wrapper.appendChild( dom.overlay );
+
+ dom.overlay.innerHTML = [
+ '<header>',
+ '<a class="close" href="#"><span class="icon"></span></a>',
+ '<a class="external" href="'+ url +'" target="_blank"><span class="icon"></span></a>',
+ '</header>',
+ '<div class="spinner"></div>',
+ '<div class="viewport">',
+ '<iframe src="'+ url +'"></iframe>',
+ '</div>'
+ ].join('');
+
+ dom.overlay.querySelector( 'iframe' ).addEventListener( 'load', function( event ) {
+ dom.overlay.classList.add( 'loaded' );
+ }, false );
+
+ dom.overlay.querySelector( '.close' ).addEventListener( 'click', function( event ) {
+ closeOverlay();
+ event.preventDefault();
+ }, false );
+
+ dom.overlay.querySelector( '.external' ).addEventListener( 'click', function( event ) {
+ closeOverlay();
+ }, false );
+
+ setTimeout( function() {
+ dom.overlay.classList.add( 'visible' );
+ }, 1 );
+
+ }
+
+ /**
+ * Opens a overlay window with help material.
+ */
+ function showHelp() {
+
+ if( config.help ) {
+
+ closeOverlay();
+
+ dom.overlay = document.createElement( 'div' );
+ dom.overlay.classList.add( 'overlay' );
+ dom.overlay.classList.add( 'overlay-help' );
+ dom.wrapper.appendChild( dom.overlay );
+
+ var html = '<p class="title">Keyboard Shortcuts</p><br/>';
+
+ html += '<table><th>KEY</th><th>ACTION</th>';
+ for( var key in keyboardShortcuts ) {
+ html += '<tr><td>' + key + '</td><td>' + keyboardShortcuts[ key ] + '</td></tr>';
+ }
+
+ html += '</table>';
+
+ dom.overlay.innerHTML = [
+ '<header>',
+ '<a class="close" href="#"><span class="icon"></span></a>',
+ '</header>',
+ '<div class="viewport">',
+ '<div class="viewport-inner">'+ html +'</div>',
+ '</div>'
+ ].join('');
+
+ dom.overlay.querySelector( '.close' ).addEventListener( 'click', function( event ) {
+ closeOverlay();
+ event.preventDefault();
+ }, false );
+
+ setTimeout( function() {
+ dom.overlay.classList.add( 'visible' );
+ }, 1 );
+
+ }
+
+ }
+
+ /**
+ * Closes any currently open overlay.
+ */
+ function closeOverlay() {
+
+ if( dom.overlay ) {
+ dom.overlay.parentNode.removeChild( dom.overlay );
+ dom.overlay = null;
+ }
+
+ }
+
+ /**
+ * Applies JavaScript-controlled layout rules to the
+ * presentation.
+ */
+ function layout() {
+
+ if( dom.wrapper && !isPrintingPDF() ) {
+
+ var size = getComputedSlideSize();
+
+ var slidePadding = 20; // TODO Dig this out of DOM
+
+ // Layout the contents of the slides
+ layoutSlideContents( config.width, config.height, slidePadding );
+
+ dom.slides.style.width = size.width + 'px';
+ dom.slides.style.height = size.height + 'px';
+
+ // Determine scale of content to fit within available space
+ scale = Math.min( size.presentationWidth / size.width, size.presentationHeight / size.height );
+
+ // Respect max/min scale settings
+ scale = Math.max( scale, config.minScale );
+ scale = Math.min( scale, config.maxScale );
+
+ // Don't apply any scaling styles if scale is 1
+ if( scale === 1 ) {
+ dom.slides.style.zoom = '';
+ dom.slides.style.left = '';
+ dom.slides.style.top = '';
+ dom.slides.style.bottom = '';
+ dom.slides.style.right = '';
+ transformSlides( { layout: '' } );
+ }
+ else {
+ // Prefer zoom for scaling up so that content remains crisp.
+ // Don't use zoom to scale down since that can lead to shifts
+ // in text layout/line breaks.
+ if( scale > 1 && features.zoom ) {
+ dom.slides.style.zoom = scale;
+ dom.slides.style.left = '';
+ dom.slides.style.top = '';
+ dom.slides.style.bottom = '';
+ dom.slides.style.right = '';
+ transformSlides( { layout: '' } );
+ }
+ // Apply scale transform as a fallback
+ else {
+ dom.slides.style.zoom = '';
+ dom.slides.style.left = '50%';
+ dom.slides.style.top = '50%';
+ dom.slides.style.bottom = 'auto';
+ dom.slides.style.right = 'auto';
+ transformSlides( { layout: 'translate(-50%, -50%) scale('+ scale +')' } );
+ }
+ }
+
+ // Select all slides, vertical and horizontal
+ var slides = toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) );
+
+ for( var i = 0, len = slides.length; i < len; i++ ) {
+ var slide = slides[ i ];
+
+ // Don't bother updating invisible slides
+ if( slide.style.display === 'none' ) {
+ continue;
+ }
+
+ if( config.center || slide.classList.contains( 'center' ) ) {
+ // Vertical stacks are not centred since their section
+ // children will be
+ if( slide.classList.contains( 'stack' ) ) {
+ slide.style.top = 0;
+ }
+ else {
+ slide.style.top = Math.max( ( ( size.height - getAbsoluteHeight( slide ) ) / 2 ) - slidePadding, 0 ) + 'px';
+ }
+ }
+ else {
+ slide.style.top = '';
+ }
+
+ }
+
+ updateProgress();
+ updateParallax();
+
+ }
+
+ }
+
+ /**
+ * Applies layout logic to the contents of all slides in
+ * the presentation.
+ */
+ function layoutSlideContents( width, height, padding ) {
+
+ // Handle sizing of elements with the 'stretch' class
+ toArray( dom.slides.querySelectorAll( 'section > .stretch' ) ).forEach( function( element ) {
+
+ // Determine how much vertical space we can use
+ var remainingHeight = getRemainingHeight( element, height );
+
+ // Consider the aspect ratio of media elements
+ if( /(img|video)/gi.test( element.nodeName ) ) {
+ var nw = element.naturalWidth || element.videoWidth,
+ nh = element.naturalHeight || element.videoHeight;
+
+ var es = Math.min( width / nw, remainingHeight / nh );
+
+ element.style.width = ( nw * es ) + 'px';
+ element.style.height = ( nh * es ) + 'px';
+
+ }
+ else {
+ element.style.width = width + 'px';
+ element.style.height = remainingHeight + 'px';
+ }
+
+ } );
+
+ }
+
+ /**
+ * Calculates the computed pixel size of our slides. These
+ * values are based on the width and height configuration
+ * options.
+ */
+ function getComputedSlideSize( presentationWidth, presentationHeight ) {
+
+ var size = {
+ // Slide size
+ width: config.width,
+ height: config.height,
+
+ // Presentation size
+ presentationWidth: presentationWidth || dom.wrapper.offsetWidth,
+ presentationHeight: presentationHeight || dom.wrapper.offsetHeight
+ };
+
+ // Reduce available space by margin
+ size.presentationWidth -= ( size.presentationWidth * config.margin );
+ size.presentationHeight -= ( size.presentationHeight * config.margin );
+
+ // Slide width may be a percentage of available width
+ if( typeof size.width === 'string' && /%$/.test( size.width ) ) {
+ size.width = parseInt( size.width, 10 ) / 100 * size.presentationWidth;
+ }
+
+ // Slide height may be a percentage of available height
+ if( typeof size.height === 'string' && /%$/.test( size.height ) ) {
+ size.height = parseInt( size.height, 10 ) / 100 * size.presentationHeight;
+ }
+
+ return size;
+
+ }
+
+ /**
+ * Stores the vertical index of a stack so that the same
+ * vertical slide can be selected when navigating to and
+ * from the stack.
+ *
+ * @param {HTMLElement} stack The vertical stack element
+ * @param {int} v Index to memorize
+ */
+ function setPreviousVerticalIndex( stack, v ) {
+
+ if( typeof stack === 'object' && typeof stack.setAttribute === 'function' ) {
+ stack.setAttribute( 'data-previous-indexv', v || 0 );
+ }
+
+ }
+
+ /**
+ * Retrieves the vertical index which was stored using
+ * #setPreviousVerticalIndex() or 0 if no previous index
+ * exists.
+ *
+ * @param {HTMLElement} stack The vertical stack element
+ */
+ function getPreviousVerticalIndex( stack ) {
+
+ if( typeof stack === 'object' && typeof stack.setAttribute === 'function' && stack.classList.contains( 'stack' ) ) {
+ // Prefer manually defined start-indexv
+ var attributeName = stack.hasAttribute( 'data-start-indexv' ) ? 'data-start-indexv' : 'data-previous-indexv';
+
+ return parseInt( stack.getAttribute( attributeName ) || 0, 10 );
+ }
+
+ return 0;
+
+ }
+
+ /**
+ * Displays the overview of slides (quick nav) by scaling
+ * down and arranging all slide elements.
+ */
+ function activateOverview() {
+
+ // Only proceed if enabled in config
+ if( config.overview && !isOverview() ) {
+
+ overview = true;
+
+ dom.wrapper.classList.add( 'overview' );
+ dom.wrapper.classList.remove( 'overview-deactivating' );
+
+ if( features.overviewTransitions ) {
+ setTimeout( function() {
+ dom.wrapper.classList.add( 'overview-animated' );
+ }, 1 );
+ }
+
+ // Don't auto-slide while in overview mode
+ cancelAutoSlide();
+
+ // Move the backgrounds element into the slide container to
+ // that the same scaling is applied
+ dom.slides.appendChild( dom.background );
+
+ // Clicking on an overview slide navigates to it
+ toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) ).forEach( function( slide ) {
+ if( !slide.classList.contains( 'stack' ) ) {
+ slide.addEventListener( 'click', onOverviewSlideClicked, true );
+ }
+ } );
+
+ // Calculate slide sizes
+ var margin = 70;
+ var slideSize = getComputedSlideSize();
+ overviewSlideWidth = slideSize.width + margin;
+ overviewSlideHeight = slideSize.height + margin;
+
+ // Reverse in RTL mode
+ if( config.rtl ) {
+ overviewSlideWidth = -overviewSlideWidth;
+ }
+
+ updateSlidesVisibility();
+ layoutOverview();
+ updateOverview();
+
+ layout();
+
+ // Notify observers of the overview showing
+ dispatchEvent( 'overviewshown', {
+ 'indexh': indexh,
+ 'indexv': indexv,
+ 'currentSlide': currentSlide
+ } );
+
+ }
+
+ }
+
+ /**
+ * Uses CSS transforms to position all slides in a grid for
+ * display inside of the overview mode.
+ */
+ function layoutOverview() {
+
+ // Layout slides
+ toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).forEach( function( hslide, h ) {
+ hslide.setAttribute( 'data-index-h', h );
+ transformElement( hslide, 'translate3d(' + ( h * overviewSlideWidth ) + 'px, 0, 0)' );
+
+ if( hslide.classList.contains( 'stack' ) ) {
+
+ toArray( hslide.querySelectorAll( 'section' ) ).forEach( function( vslide, v ) {
+ vslide.setAttribute( 'data-index-h', h );
+ vslide.setAttribute( 'data-index-v', v );
+
+ transformElement( vslide, 'translate3d(0, ' + ( v * overviewSlideHeight ) + 'px, 0)' );
+ } );
+
+ }
+ } );
+
+ // Layout slide backgrounds
+ toArray( dom.background.childNodes ).forEach( function( hbackground, h ) {
+ transformElement( hbackground, 'translate3d(' + ( h * overviewSlideWidth ) + 'px, 0, 0)' );
+
+ toArray( hbackground.querySelectorAll( '.slide-background' ) ).forEach( function( vbackground, v ) {
+ transformElement( vbackground, 'translate3d(0, ' + ( v * overviewSlideHeight ) + 'px, 0)' );
+ } );
+ } );
+
+ }
+
+ /**
+ * Moves the overview viewport to the current slides.
+ * Called each time the current slide changes.
+ */
+ function updateOverview() {
+
+ transformSlides( {
+ overview: [
+ 'translateX('+ ( -indexh * overviewSlideWidth ) +'px)',
+ 'translateY('+ ( -indexv * overviewSlideHeight ) +'px)',
+ 'translateZ('+ ( window.innerWidth < 400 ? -1000 : -2500 ) +'px)'
+ ].join( ' ' )
+ } );
+
+ }
+
+ /**
+ * Exits the slide overview and enters the currently
+ * active slide.
+ */
+ function deactivateOverview() {
+
+ // Only proceed if enabled in config
+ if( config.overview ) {
+
+ overview = false;
+
+ dom.wrapper.classList.remove( 'overview' );
+ dom.wrapper.classList.remove( 'overview-animated' );
+
+ // Temporarily add a class so that transitions can do different things
+ // depending on whether they are exiting/entering overview, or just
+ // moving from slide to slide
+ dom.wrapper.classList.add( 'overview-deactivating' );
+
+ setTimeout( function () {
+ dom.wrapper.classList.remove( 'overview-deactivating' );
+ }, 1 );
+
+ // Move the background element back out
+ dom.wrapper.appendChild( dom.background );
+
+ // Clean up changes made to slides
+ toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) ).forEach( function( slide ) {
+ transformElement( slide, '' );
+
+ slide.removeEventListener( 'click', onOverviewSlideClicked, true );
+ } );
+
+ // Clean up changes made to backgrounds
+ toArray( dom.background.querySelectorAll( '.slide-background' ) ).forEach( function( background ) {
+ transformElement( background, '' );
+ } );
+
+ transformSlides( { overview: '' } );
+
+ slide( indexh, indexv );
+
+ layout();
+
+ cueAutoSlide();
+
+ // Notify observers of the overview hiding
+ dispatchEvent( 'overviewhidden', {
+ 'indexh': indexh,
+ 'indexv': indexv,
+ 'currentSlide': currentSlide
+ } );
+
+ }
+ }
+
+ /**
+ * Toggles the slide overview mode on and off.
+ *
+ * @param {Boolean} override Optional flag which overrides the
+ * toggle logic and forcibly sets the desired state. True means
+ * overview is open, false means it's closed.
+ */
+ function toggleOverview( override ) {
+
+ if( typeof override === 'boolean' ) {
+ override ? activateOverview() : deactivateOverview();
+ }
+ else {
+ isOverview() ? deactivateOverview() : activateOverview();
+ }
+
+ }
+
+ /**
+ * Checks if the overview is currently active.
+ *
+ * @return {Boolean} true if the overview is active,
+ * false otherwise
+ */
+ function isOverview() {
+
+ return overview;
+
+ }
+
+ /**
+ * Checks if the current or specified slide is vertical
+ * (nested within another slide).
+ *
+ * @param {HTMLElement} slide [optional] The slide to check
+ * orientation of
+ */
+ function isVerticalSlide( slide ) {
+
+ // Prefer slide argument, otherwise use current slide
+ slide = slide ? slide : currentSlide;
+
+ return slide && slide.parentNode && !!slide.parentNode.nodeName.match( /section/i );
+
+ }
+
+ /**
+ * Handling the fullscreen functionality via the fullscreen API
+ *
+ * @see http://fullscreen.spec.whatwg.org/
+ * @see https://developer.mozilla.org/en-US/docs/DOM/Using_fullscreen_mode
+ */
+ function enterFullscreen() {
+
+ var element = document.documentElement;
+
+ // Check which implementation is available
+ var requestMethod = element.requestFullscreen ||
+ element.webkitRequestFullscreen ||
+ element.webkitRequestFullScreen ||
+ element.mozRequestFullScreen ||
+ element.msRequestFullscreen;
+
+ if( requestMethod ) {
+ requestMethod.apply( element );
+ }
+
+ }
+
+ /**
+ * Enters the paused mode which fades everything on screen to
+ * black.
+ */
+ function pause() {
+
+ if( config.pause ) {
+ var wasPaused = dom.wrapper.classList.contains( 'paused' );
+
+ cancelAutoSlide();
+ dom.wrapper.classList.add( 'paused' );
+
+ if( wasPaused === false ) {
+ dispatchEvent( 'paused' );
+ }
+ }
+
+ }
+
+ /**
+ * Exits from the paused mode.
+ */
+ function resume() {
+
+ var wasPaused = dom.wrapper.classList.contains( 'paused' );
+ dom.wrapper.classList.remove( 'paused' );
+
+ cueAutoSlide();
+
+ if( wasPaused ) {
+ dispatchEvent( 'resumed' );
+ }
+
+ }
+
+ /**
+ * Toggles the paused mode on and off.
+ */
+ function togglePause( override ) {
+
+ if( typeof override === 'boolean' ) {
+ override ? pause() : resume();
+ }
+ else {
+ isPaused() ? resume() : pause();
+ }
+
+ }
+
+ /**
+ * Checks if we are currently in the paused mode.
+ */
+ function isPaused() {
+
+ return dom.wrapper.classList.contains( 'paused' );
+
+ }
+
+ /**
+ * Toggles the auto slide mode on and off.
+ *
+ * @param {Boolean} override Optional flag which sets the desired state.
+ * True means autoplay starts, false means it stops.
+ */
+
+ function toggleAutoSlide( override ) {
+
+ if( typeof override === 'boolean' ) {
+ override ? resumeAutoSlide() : pauseAutoSlide();
+ }
+
+ else {
+ autoSlidePaused ? resumeAutoSlide() : pauseAutoSlide();
+ }
+
+ }
+
+ /**
+ * Checks if the auto slide mode is currently on.
+ */
+ function isAutoSliding() {
+
+ return !!( autoSlide && !autoSlidePaused );
+
+ }
+
+ /**
+ * Steps from the current point in the presentation to the
+ * slide which matches the specified horizontal and vertical
+ * indices.
+ *
+ * @param {int} h Horizontal index of the target slide
+ * @param {int} v Vertical index of the target slide
+ * @param {int} f Optional index of a fragment within the
+ * target slide to activate
+ * @param {int} o Optional origin for use in multimaster environments
+ */
+ function slide( h, v, f, o ) {
+
+ // Remember where we were at before
+ previousSlide = currentSlide;
+
+ // Query all horizontal slides in the deck
+ var horizontalSlides = dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR );
+
+ // If no vertical index is specified and the upcoming slide is a
+ // stack, resume at its previous vertical index
+ if( v === undefined && !isOverview() ) {
+ v = getPreviousVerticalIndex( horizontalSlides[ h ] );
+ }
+
+ // If we were on a vertical stack, remember what vertical index
+ // it was on so we can resume at the same position when returning
+ if( previousSlide && previousSlide.parentNode && previousSlide.parentNode.classList.contains( 'stack' ) ) {
+ setPreviousVerticalIndex( previousSlide.parentNode, indexv );
+ }
+
+ // Remember the state before this slide
+ var stateBefore = state.concat();
+
+ // Reset the state array
+ state.length = 0;
+
+ var indexhBefore = indexh || 0,
+ indexvBefore = indexv || 0;
+
+ // Activate and transition to the new slide
+ indexh = updateSlides( HORIZONTAL_SLIDES_SELECTOR, h === undefined ? indexh : h );
+ indexv = updateSlides( VERTICAL_SLIDES_SELECTOR, v === undefined ? indexv : v );
+
+ // Update the visibility of slides now that the indices have changed
+ updateSlidesVisibility();
+
+ layout();
+
+ // Apply the new state
+ stateLoop: for( var i = 0, len = state.length; i < len; i++ ) {
+ // Check if this state existed on the previous slide. If it
+ // did, we will avoid adding it repeatedly
+ for( var j = 0; j < stateBefore.length; j++ ) {
+ if( stateBefore[j] === state[i] ) {
+ stateBefore.splice( j, 1 );
+ continue stateLoop;
+ }
+ }
+
+ document.documentElement.classList.add( state[i] );
+
+ // Dispatch custom event matching the state's name
+ dispatchEvent( state[i] );
+ }
+
+ // Clean up the remains of the previous state
+ while( stateBefore.length ) {
+ document.documentElement.classList.remove( stateBefore.pop() );
+ }
+
+ // Update the overview if it's currently active
+ if( isOverview() ) {
+ updateOverview();
+ }
+
+ // Find the current horizontal slide and any possible vertical slides
+ // within it
+ var currentHorizontalSlide = horizontalSlides[ indexh ],
+ currentVerticalSlides = currentHorizontalSlide.querySelectorAll( 'section' );
+
+ // Store references to the previous and current slides
+ currentSlide = currentVerticalSlides[ indexv ] || currentHorizontalSlide;
+
+ // Show fragment, if specified
+ if( typeof f !== 'undefined' ) {
+ navigateFragment( f );
+ }
+
+ // Dispatch an event if the slide changed
+ var slideChanged = ( indexh !== indexhBefore || indexv !== indexvBefore );
+ if( slideChanged ) {
+ dispatchEvent( 'slidechanged', {
+ 'indexh': indexh,
+ 'indexv': indexv,
+ 'previousSlide': previousSlide,
+ 'currentSlide': currentSlide,
+ 'origin': o
+ } );
+ }
+ else {
+ // Ensure that the previous slide is never the same as the current
+ previousSlide = null;
+ }
+
+ // Solves an edge case where the previous slide maintains the
+ // 'present' class when navigating between adjacent vertical
+ // stacks
+ if( previousSlide ) {
+ previousSlide.classList.remove( 'present' );
+ previousSlide.setAttribute( 'aria-hidden', 'true' );
+
+ // Reset all slides upon navigate to home
+ // Issue: #285
+ if ( dom.wrapper.querySelector( HOME_SLIDE_SELECTOR ).classList.contains( 'present' ) ) {
+ // Launch async task
+ setTimeout( function () {
+ var slides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.stack') ), i;
+ for( i in slides ) {
+ if( slides[i] ) {
+ // Reset stack
+ setPreviousVerticalIndex( slides[i], 0 );
+ }
+ }
+ }, 0 );
+ }
+ }
+
+ // Handle embedded content
+ if( slideChanged || !previousSlide ) {
+ stopEmbeddedContent( previousSlide );
+ startEmbeddedContent( currentSlide );
+ }
+
+ // Announce the current slide contents, for screen readers
+ dom.statusDiv.textContent = currentSlide.textContent;
+
+ updateControls();
+ updateProgress();
+ updateBackground();
+ updateParallax();
+ updateSlideNumber();
+ updateNotes();
+
+ // Update the URL hash
+ writeURL();
+
+ cueAutoSlide();
+
+ }
+
+ /**
+ * Syncs the presentation with the current DOM. Useful
+ * when new slides or control elements are added or when
+ * the configuration has changed.
+ */
+ function sync() {
+
+ // Subscribe to input
+ removeEventListeners();
+ addEventListeners();
+
+ // Force a layout to make sure the current config is accounted for
+ layout();
+
+ // Reflect the current autoSlide value
+ autoSlide = config.autoSlide;
+
+ // Start auto-sliding if it's enabled
+ cueAutoSlide();
+
+ // Re-create the slide backgrounds
+ createBackgrounds();
+
+ // Write the current hash to the URL
+ writeURL();
+
+ sortAllFragments();
+
+ updateControls();
+ updateProgress();
+ updateBackground( true );
+ updateSlideNumber();
+ updateSlidesVisibility();
+ updateNotes();
+
+ formatEmbeddedContent();
+ startEmbeddedContent( currentSlide );
+
+ if( isOverview() ) {
+ layoutOverview();
+ }
+
+ }
+
+ /**
+ * Resets all vertical slides so that only the first
+ * is visible.
+ */
+ function resetVerticalSlides() {
+
+ var horizontalSlides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
+ horizontalSlides.forEach( function( horizontalSlide ) {
+
+ var verticalSlides = toArray( horizontalSlide.querySelectorAll( 'section' ) );
+ verticalSlides.forEach( function( verticalSlide, y ) {
+
+ if( y > 0 ) {
+ verticalSlide.classList.remove( 'present' );
+ verticalSlide.classList.remove( 'past' );
+ verticalSlide.classList.add( 'future' );
+ verticalSlide.setAttribute( 'aria-hidden', 'true' );
+ }
+
+ } );
+
+ } );
+
+ }
+
+ /**
+ * Sorts and formats all of fragments in the
+ * presentation.
+ */
+ function sortAllFragments() {
+
+ var horizontalSlides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
+ horizontalSlides.forEach( function( horizontalSlide ) {
+
+ var verticalSlides = toArray( horizontalSlide.querySelectorAll( 'section' ) );
+ verticalSlides.forEach( function( verticalSlide, y ) {
+
+ sortFragments( verticalSlide.querySelectorAll( '.fragment' ) );
+
+ } );
+
+ if( verticalSlides.length === 0 ) sortFragments( horizontalSlide.querySelectorAll( '.fragment' ) );
+
+ } );
+
+ }
+
+ /**
+ * Randomly shuffles all slides in the deck.
+ */
+ function shuffle() {
+
+ var slides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
+
+ slides.forEach( function( slide ) {
+
+ // Insert this slide next to another random slide. This may
+ // cause the slide to insert before itself but that's fine.
+ dom.slides.insertBefore( slide, slides[ Math.floor( Math.random() * slides.length ) ] );
+
+ } );
+
+ }
+
+ /**
+ * Updates one dimension of slides by showing the slide
+ * with the specified index.
+ *
+ * @param {String} selector A CSS selector that will fetch
+ * the group of slides we are working with
+ * @param {Number} index The index of the slide that should be
+ * shown
+ *
+ * @return {Number} The index of the slide that is now shown,
+ * might differ from the passed in index if it was out of
+ * bounds.
+ */
+ function updateSlides( selector, index ) {
+
+ // Select all slides and convert the NodeList result to
+ // an array
+ var slides = toArray( dom.wrapper.querySelectorAll( selector ) ),
+ slidesLength = slides.length;
+
+ var printMode = isPrintingPDF();
+
+ if( slidesLength ) {
+
+ // Should the index loop?
+ if( config.loop ) {
+ index %= slidesLength;
+
+ if( index < 0 ) {
+ index = slidesLength + index;
+ }
+ }
+
+ // Enforce max and minimum index bounds
+ index = Math.max( Math.min( index, slidesLength - 1 ), 0 );
+
+ for( var i = 0; i < slidesLength; i++ ) {
+ var element = slides[i];
+
+ var reverse = config.rtl && !isVerticalSlide( element );
+
+ element.classList.remove( 'past' );
+ element.classList.remove( 'present' );
+ element.classList.remove( 'future' );
+
+ // http://www.w3.org/html/wg/drafts/html/master/editing.html#the-hidden-attribute
+ element.setAttribute( 'hidden', '' );
+ element.setAttribute( 'aria-hidden', 'true' );
+
+ // If this element contains vertical slides
+ if( element.querySelector( 'section' ) ) {
+ element.classList.add( 'stack' );
+ }
+
+ // If we're printing static slides, all slides are "present"
+ if( printMode ) {
+ element.classList.add( 'present' );
+ continue;
+ }
+
+ if( i < index ) {
+ // Any element previous to index is given the 'past' class
+ element.classList.add( reverse ? 'future' : 'past' );
+
+ if( config.fragments ) {
+ var pastFragments = toArray( element.querySelectorAll( '.fragment' ) );
+
+ // Show all fragments on prior slides
+ while( pastFragments.length ) {
+ var pastFragment = pastFragments.pop();
+ pastFragment.classList.add( 'visible' );
+ pastFragment.classList.remove( 'current-fragment' );
+ }
+ }
+ }
+ else if( i > index ) {
+ // Any element subsequent to index is given the 'future' class
+ element.classList.add( reverse ? 'past' : 'future' );
+
+ if( config.fragments ) {
+ var futureFragments = toArray( element.querySelectorAll( '.fragment.visible' ) );
+
+ // No fragments in future slides should be visible ahead of time
+ while( futureFragments.length ) {
+ var futureFragment = futureFragments.pop();
+ futureFragment.classList.remove( 'visible' );
+ futureFragment.classList.remove( 'current-fragment' );
+ }
+ }
+ }
+ }
+
+ // Mark the current slide as present
+ slides[index].classList.add( 'present' );
+ slides[index].removeAttribute( 'hidden' );
+ slides[index].removeAttribute( 'aria-hidden' );
+
+ // If this slide has a state associated with it, add it
+ // onto the current state of the deck
+ var slideState = slides[index].getAttribute( 'data-state' );
+ if( slideState ) {
+ state = state.concat( slideState.split( ' ' ) );
+ }
+
+ }
+ else {
+ // Since there are no slides we can't be anywhere beyond the
+ // zeroth index
+ index = 0;
+ }
+
+ return index;
+
+ }
+
+ /**
+ * Optimization method; hide all slides that are far away
+ * from the present slide.
+ */
+ function updateSlidesVisibility() {
+
+ // Select all slides and convert the NodeList result to
+ // an array
+ var horizontalSlides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ),
+ horizontalSlidesLength = horizontalSlides.length,
+ distanceX,
+ distanceY;
+
+ if( horizontalSlidesLength && typeof indexh !== 'undefined' ) {
+
+ // The number of steps away from the present slide that will
+ // be visible
+ var viewDistance = isOverview() ? 10 : config.viewDistance;
+
+ // Limit view distance on weaker devices
+ if( isMobileDevice ) {
+ viewDistance = isOverview() ? 6 : 2;
+ }
+
+ // All slides need to be visible when exporting to PDF
+ if( isPrintingPDF() ) {
+ viewDistance = Number.MAX_VALUE;
+ }
+
+ for( var x = 0; x < horizontalSlidesLength; x++ ) {
+ var horizontalSlide = horizontalSlides[x];
+
+ var verticalSlides = toArray( horizontalSlide.querySelectorAll( 'section' ) ),
+ verticalSlidesLength = verticalSlides.length;
+
+ // Determine how far away this slide is from the present
+ distanceX = Math.abs( ( indexh || 0 ) - x ) || 0;
+
+ // If the presentation is looped, distance should measure
+ // 1 between the first and last slides
+ if( config.loop ) {
+ distanceX = Math.abs( ( ( indexh || 0 ) - x ) % ( horizontalSlidesLength - viewDistance ) ) || 0;
+ }
+
+ // Show the horizontal slide if it's within the view distance
+ if( distanceX < viewDistance ) {
+ showSlide( horizontalSlide );
+ }
+ else {
+ hideSlide( horizontalSlide );
+ }
+
+ if( verticalSlidesLength ) {
+
+ var oy = getPreviousVerticalIndex( horizontalSlide );
+
+ for( var y = 0; y < verticalSlidesLength; y++ ) {
+ var verticalSlide = verticalSlides[y];
+
+ distanceY = x === ( indexh || 0 ) ? Math.abs( ( indexv || 0 ) - y ) : Math.abs( y - oy );
+
+ if( distanceX + distanceY < viewDistance ) {
+ showSlide( verticalSlide );
+ }
+ else {
+ hideSlide( verticalSlide );
+ }
+ }
+
+ }
+ }
+
+ }
+
+ }
+
+ /**
+ * Pick up notes from the current slide and display tham
+ * to the viewer.
+ *
+ * @see `showNotes` config value
+ */
+ function updateNotes() {
+
+ if( config.showNotes && dom.speakerNotes && currentSlide && !isPrintingPDF() ) {
+
+ dom.speakerNotes.innerHTML = getSlideNotes() || '';
+
+ }
+
+ }
+
+ /**
+ * Updates the progress bar to reflect the current slide.
+ */
+ function updateProgress() {
+
+ // Update progress if enabled
+ if( config.progress && dom.progressbar ) {
+
+ dom.progressbar.style.width = getProgress() * dom.wrapper.offsetWidth + 'px';
+
+ }
+
+ }
+
+ /**
+ * Updates the slide number div to reflect the current slide.
+ *
+ * The following slide number formats are available:
+ * "h.v": horizontal . vertical slide number (default)
+ * "h/v": horizontal / vertical slide number
+ * "c": flattened slide number
+ * "c/t": flattened slide number / total slides
+ */
+ function updateSlideNumber() {
+
+ // Update slide number if enabled
+ if( config.slideNumber && dom.slideNumber ) {
+
+ var value = [];
+ var format = 'h.v';
+
+ // Check if a custom number format is available
+ if( typeof config.slideNumber === 'string' ) {
+ format = config.slideNumber;
+ }
+
+ switch( format ) {
+ case 'c':
+ value.push( getSlidePastCount() + 1 );
+ break;
+ case 'c/t':
+ value.push( getSlidePastCount() + 1, '/', getTotalSlides() );
+ break;
+ case 'h/v':
+ value.push( indexh + 1 );
+ if( isVerticalSlide() ) value.push( '/', indexv + 1 );
+ break;
+ default:
+ value.push( indexh + 1 );
+ if( isVerticalSlide() ) value.push( '.', indexv + 1 );
+ }
+
+ dom.slideNumber.innerHTML = formatSlideNumber( value[0], value[1], value[2] );
+ }
+
+ }
+
+ /**
+ * Applies HTML formatting to a slide number before it's
+ * written to the DOM.
+ */
+ function formatSlideNumber( a, delimiter, b ) {
+
+ if( typeof b === 'number' && !isNaN( b ) ) {
+ return '<span class="slide-number-a">'+ a +'</span>' +
+ '<span class="slide-number-delimiter">'+ delimiter +'</span>' +
+ '<span class="slide-number-b">'+ b +'</span>';
+ }
+ else {
+ return '<span class="slide-number-a">'+ a +'</span>';
+ }
+
+ }
+
+ /**
+ * Updates the state of all control/navigation arrows.
+ */
+ function updateControls() {
+
+ var routes = availableRoutes();
+ var fragments = availableFragments();
+
+ // Remove the 'enabled' class from all directions
+ dom.controlsLeft.concat( dom.controlsRight )
+ .concat( dom.controlsUp )
+ .concat( dom.controlsDown )
+ .concat( dom.controlsPrev )
+ .concat( dom.controlsNext ).forEach( function( node ) {
+ node.classList.remove( 'enabled' );
+ node.classList.remove( 'fragmented' );
+ } );
+
+ // Add the 'enabled' class to the available routes
+ if( routes.left ) dom.controlsLeft.forEach( function( el ) { el.classList.add( 'enabled' ); } );
+ if( routes.right ) dom.controlsRight.forEach( function( el ) { el.classList.add( 'enabled' ); } );
+ if( routes.up ) dom.controlsUp.forEach( function( el ) { el.classList.add( 'enabled' ); } );
+ if( routes.down ) dom.controlsDown.forEach( function( el ) { el.classList.add( 'enabled' ); } );
+
+ // Prev/next buttons
+ if( routes.left || routes.up ) dom.controlsPrev.forEach( function( el ) { el.classList.add( 'enabled' ); } );
+ if( routes.right || routes.down ) dom.controlsNext.forEach( function( el ) { el.classList.add( 'enabled' ); } );
+
+ // Highlight fragment directions
+ if( currentSlide ) {
+
+ // Always apply fragment decorator to prev/next buttons
+ if( fragments.prev ) dom.controlsPrev.forEach( function( el ) { el.classList.add( 'fragmented', 'enabled' ); } );
+ if( fragments.next ) dom.controlsNext.forEach( function( el ) { el.classList.add( 'fragmented', 'enabled' ); } );
+
+ // Apply fragment decorators to directional buttons based on
+ // what slide axis they are in
+ if( isVerticalSlide( currentSlide ) ) {
+ if( fragments.prev ) dom.controlsUp.forEach( function( el ) { el.classList.add( 'fragmented', 'enabled' ); } );
+ if( fragments.next ) dom.controlsDown.forEach( function( el ) { el.classList.add( 'fragmented', 'enabled' ); } );
+ }
+ else {
+ if( fragments.prev ) dom.controlsLeft.forEach( function( el ) { el.classList.add( 'fragmented', 'enabled' ); } );
+ if( fragments.next ) dom.controlsRight.forEach( function( el ) { el.classList.add( 'fragmented', 'enabled' ); } );
+ }
+
+ }
+
+ }
+
+ /**
+ * Updates the background elements to reflect the current
+ * slide.
+ *
+ * @param {Boolean} includeAll If true, the backgrounds of
+ * all vertical slides (not just the present) will be updated.
+ */
+ function updateBackground( includeAll ) {
+
+ var currentBackground = null;
+
+ // Reverse past/future classes when in RTL mode
+ var horizontalPast = config.rtl ? 'future' : 'past',
+ horizontalFuture = config.rtl ? 'past' : 'future';
+
+ // Update the classes of all backgrounds to match the
+ // states of their slides (past/present/future)
+ toArray( dom.background.childNodes ).forEach( function( backgroundh, h ) {
+
+ backgroundh.classList.remove( 'past' );
+ backgroundh.classList.remove( 'present' );
+ backgroundh.classList.remove( 'future' );
+
+ if( h < indexh ) {
+ backgroundh.classList.add( horizontalPast );
+ }
+ else if ( h > indexh ) {
+ backgroundh.classList.add( horizontalFuture );
+ }
+ else {
+ backgroundh.classList.add( 'present' );
+
+ // Store a reference to the current background element
+ currentBackground = backgroundh;
+ }
+
+ if( includeAll || h === indexh ) {
+ toArray( backgroundh.querySelectorAll( '.slide-background' ) ).forEach( function( backgroundv, v ) {
+
+ backgroundv.classList.remove( 'past' );
+ backgroundv.classList.remove( 'present' );
+ backgroundv.classList.remove( 'future' );
+
+ if( v < indexv ) {
+ backgroundv.classList.add( 'past' );
+ }
+ else if ( v > indexv ) {
+ backgroundv.classList.add( 'future' );
+ }
+ else {
+ backgroundv.classList.add( 'present' );
+
+ // Only if this is the present horizontal and vertical slide
+ if( h === indexh ) currentBackground = backgroundv;
+ }
+
+ } );
+ }
+
+ } );
+
+ // Stop any currently playing video background
+ if( previousBackground ) {
+
+ var previousVideo = previousBackground.querySelector( 'video' );
+ if( previousVideo ) previousVideo.pause();
+
+ }
+
+ if( currentBackground ) {
+
+ // Start video playback
+ var currentVideo = currentBackground.querySelector( 'video' );
+ if( currentVideo ) {
+
+ var startVideo = function() {
+ currentVideo.currentTime = 0;
+ currentVideo.play();
+ currentVideo.removeEventListener( 'loadeddata', startVideo );
+ };
+
+ if( currentVideo.readyState > 1 ) {
+ startVideo();
+ }
+ else {
+ currentVideo.addEventListener( 'loadeddata', startVideo );
+ }
+
+ }
+
+ var backgroundImageURL = currentBackground.style.backgroundImage || '';
+
+ // Restart GIFs (doesn't work in Firefox)
+ if( /\.gif/i.test( backgroundImageURL ) ) {
+ currentBackground.style.backgroundImage = '';
+ window.getComputedStyle( currentBackground ).opacity;
+ currentBackground.style.backgroundImage = backgroundImageURL;
+ }
+
+ // Don't transition between identical backgrounds. This
+ // prevents unwanted flicker.
+ var previousBackgroundHash = previousBackground ? previousBackground.getAttribute( 'data-background-hash' ) : null;
+ var currentBackgroundHash = currentBackground.getAttribute( 'data-background-hash' );
+ if( currentBackgroundHash && currentBackgroundHash === previousBackgroundHash && currentBackground !== previousBackground ) {
+ dom.background.classList.add( 'no-transition' );
+ }
+
+ previousBackground = currentBackground;
+
+ }
+
+ // If there's a background brightness flag for this slide,
+ // bubble it to the .reveal container
+ if( currentSlide ) {
+ [ 'has-light-background', 'has-dark-background' ].forEach( function( classToBubble ) {
+ if( currentSlide.classList.contains( classToBubble ) ) {
+ dom.wrapper.classList.add( classToBubble );
+ }
+ else {
+ dom.wrapper.classList.remove( classToBubble );
+ }
+ } );
+ }
+
+ // Allow the first background to apply without transition
+ setTimeout( function() {
+ dom.background.classList.remove( 'no-transition' );
+ }, 1 );
+
+ }
+
+ /**
+ * Updates the position of the parallax background based
+ * on the current slide index.
+ */
+ function updateParallax() {
+
+ if( config.parallaxBackgroundImage ) {
+
+ var horizontalSlides = dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ),
+ verticalSlides = dom.wrapper.querySelectorAll( VERTICAL_SLIDES_SELECTOR );
+
+ var backgroundSize = dom.background.style.backgroundSize.split( ' ' ),
+ backgroundWidth, backgroundHeight;
+
+ if( backgroundSize.length === 1 ) {
+ backgroundWidth = backgroundHeight = parseInt( backgroundSize[0], 10 );
+ }
+ else {
+ backgroundWidth = parseInt( backgroundSize[0], 10 );
+ backgroundHeight = parseInt( backgroundSize[1], 10 );
+ }
+
+ var slideWidth = dom.background.offsetWidth,
+ horizontalSlideCount = horizontalSlides.length,
+ horizontalOffsetMultiplier,
+ horizontalOffset;
+
+ if( typeof config.parallaxBackgroundHorizontal === 'number' ) {
+ horizontalOffsetMultiplier = config.parallaxBackgroundHorizontal;
+ }
+ else {
+ horizontalOffsetMultiplier = horizontalSlideCount > 1 ? ( backgroundWidth - slideWidth ) / ( horizontalSlideCount-1 ) : 0;
+ }
+
+ horizontalOffset = horizontalOffsetMultiplier * indexh * -1;
+
+ var slideHeight = dom.background.offsetHeight,
+ verticalSlideCount = verticalSlides.length,
+ verticalOffsetMultiplier,
+ verticalOffset;
+
+ if( typeof config.parallaxBackgroundVertical === 'number' ) {
+ verticalOffsetMultiplier = config.parallaxBackgroundVertical;
+ }
+ else {
+ verticalOffsetMultiplier = ( backgroundHeight - slideHeight ) / ( verticalSlideCount-1 );
+ }
+
+ verticalOffset = verticalSlideCount > 0 ? verticalOffsetMultiplier * indexv * 1 : 0;
+
+ dom.background.style.backgroundPosition = horizontalOffset + 'px ' + -verticalOffset + 'px';
+
+ }
+
+ }
+
+ /**
+ * Called when the given slide is within the configured view
+ * distance. Shows the slide element and loads any content
+ * that is set to load lazily (data-src).
+ */
+ function showSlide( slide ) {
+
+ // Show the slide element
+ slide.style.display = 'block';
+
+ // Media elements with data-src attributes
+ toArray( slide.querySelectorAll( 'img[data-src], video[data-src], audio[data-src]' ) ).forEach( function( element ) {
+ element.setAttribute( 'src', element.getAttribute( 'data-src' ) );
+ element.removeAttribute( 'data-src' );
+ } );
+
+ // Media elements with <source> children
+ toArray( slide.querySelectorAll( 'video, audio' ) ).forEach( function( media ) {
+ var sources = 0;
+
+ toArray( media.querySelectorAll( 'source[data-src]' ) ).forEach( function( source ) {
+ source.setAttribute( 'src', source.getAttribute( 'data-src' ) );
+ source.removeAttribute( 'data-src' );
+ sources += 1;
+ } );
+
+ // If we rewrote sources for this video/audio element, we need
+ // to manually tell it to load from its new origin
+ if( sources > 0 ) {
+ media.load();
+ }
+ } );
+
+
+ // Show the corresponding background element
+ var indices = getIndices( slide );
+ var background = getSlideBackground( indices.h, indices.v );
+ if( background ) {
+ background.style.display = 'block';
+
+ // If the background contains media, load it
+ if( background.hasAttribute( 'data-loaded' ) === false ) {
+ background.setAttribute( 'data-loaded', 'true' );
+
+ var backgroundImage = slide.getAttribute( 'data-background-image' ),
+ backgroundVideo = slide.getAttribute( 'data-background-video' ),
+ backgroundVideoLoop = slide.hasAttribute( 'data-background-video-loop' ),
+ backgroundVideoMuted = slide.hasAttribute( 'data-background-video-muted' ),
+ backgroundIframe = slide.getAttribute( 'data-background-iframe' );
+
+ // Images
+ if( backgroundImage ) {
+ background.style.backgroundImage = 'url('+ backgroundImage +')';
+ }
+ // Videos
+ else if ( backgroundVideo && !isSpeakerNotes() ) {
+ var video = document.createElement( 'video' );
+
+ if( backgroundVideoLoop ) {
+ video.setAttribute( 'loop', '' );
+ }
+
+ if( backgroundVideoMuted ) {
+ video.muted = true;
+ }
+
+ // Support comma separated lists of video sources
+ backgroundVideo.split( ',' ).forEach( function( source ) {
+ video.innerHTML += '<source src="'+ source +'">';
+ } );
+
+ background.appendChild( video );
+ }
+ // Iframes
+ else if( backgroundIframe ) {
+ var iframe = document.createElement( 'iframe' );
+ iframe.setAttribute( 'src', backgroundIframe );
+ iframe.style.width = '100%';
+ iframe.style.height = '100%';
+ iframe.style.maxHeight = '100%';
+ iframe.style.maxWidth = '100%';
+
+ background.appendChild( iframe );
+ }
+ }
+ }
+
+ }
+
+ /**
+ * Called when the given slide is moved outside of the
+ * configured view distance.
+ */
+ function hideSlide( slide ) {
+
+ // Hide the slide element
+ slide.style.display = 'none';
+
+ // Hide the corresponding background element
+ var indices = getIndices( slide );
+ var background = getSlideBackground( indices.h, indices.v );
+ if( background ) {
+ background.style.display = 'none';
+ }
+
+ }
+
+ /**
+ * Determine what available routes there are for navigation.
+ *
+ * @return {Object} containing four booleans: left/right/up/down
+ */
+ function availableRoutes() {
+
+ var horizontalSlides = dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ),
+ verticalSlides = dom.wrapper.querySelectorAll( VERTICAL_SLIDES_SELECTOR );
+
+ var routes = {
+ left: indexh > 0 || config.loop,
+ right: indexh < horizontalSlides.length - 1 || config.loop,
+ up: indexv > 0,
+ down: indexv < verticalSlides.length - 1
+ };
+
+ // reverse horizontal controls for rtl
+ if( config.rtl ) {
+ var left = routes.left;
+ routes.left = routes.right;
+ routes.right = left;
+ }
+
+ return routes;
+
+ }
+
+ /**
+ * Returns an object describing the available fragment
+ * directions.
+ *
+ * @return {Object} two boolean properties: prev/next
+ */
+ function availableFragments() {
+
+ if( currentSlide && config.fragments ) {
+ var fragments = currentSlide.querySelectorAll( '.fragment' );
+ var hiddenFragments = currentSlide.querySelectorAll( '.fragment:not(.visible)' );
+
+ return {
+ prev: fragments.length - hiddenFragments.length > 0,
+ next: !!hiddenFragments.length
+ };
+ }
+ else {
+ return { prev: false, next: false };
+ }
+
+ }
+
+ /**
+ * Enforces origin-specific format rules for embedded media.
+ */
+ function formatEmbeddedContent() {
+
+ var _appendParamToIframeSource = function( sourceAttribute, sourceURL, param ) {
+ toArray( dom.slides.querySelectorAll( 'iframe['+ sourceAttribute +'*="'+ sourceURL +'"]' ) ).forEach( function( el ) {
+ var src = el.getAttribute( sourceAttribute );
+ if( src && src.indexOf( param ) === -1 ) {
+ el.setAttribute( sourceAttribute, src + ( !/\?/.test( src ) ? '?' : '&' ) + param );
+ }
+ });
+ };
+
+ // YouTube frames must include "?enablejsapi=1"
+ _appendParamToIframeSource( 'src', 'youtube.com/embed/', 'enablejsapi=1' );
+ _appendParamToIframeSource( 'data-src', 'youtube.com/embed/', 'enablejsapi=1' );
+
+ // Vimeo frames must include "?api=1"
+ _appendParamToIframeSource( 'src', 'player.vimeo.com/', 'api=1' );
+ _appendParamToIframeSource( 'data-src', 'player.vimeo.com/', 'api=1' );
+
+ }
+
+ /**
+ * Start playback of any embedded content inside of
+ * the targeted slide.
+ */
+ function startEmbeddedContent( slide ) {
+
+ if( slide && !isSpeakerNotes() ) {
+ // Restart GIFs
+ toArray( slide.querySelectorAll( 'img[src$=".gif"]' ) ).forEach( function( el ) {
+ // Setting the same unchanged source like this was confirmed
+ // to work in Chrome, FF & Safari
+ el.setAttribute( 'src', el.getAttribute( 'src' ) );
+ } );
+
+ // HTML5 media elements
+ toArray( slide.querySelectorAll( 'video, audio' ) ).forEach( function( el ) {
+ if( el.hasAttribute( 'data-autoplay' ) && typeof el.play === 'function' ) {
+ el.play();
+ }
+ } );
+
+ // Normal iframes
+ toArray( slide.querySelectorAll( 'iframe[src]' ) ).forEach( function( el ) {
+ startEmbeddedIframe( { target: el } );
+ } );
+
+ // Lazy loading iframes
+ toArray( slide.querySelectorAll( 'iframe[data-src]' ) ).forEach( function( el ) {
+ if( el.getAttribute( 'src' ) !== el.getAttribute( 'data-src' ) ) {
+ el.removeEventListener( 'load', startEmbeddedIframe ); // remove first to avoid dupes
+ el.addEventListener( 'load', startEmbeddedIframe );
+ el.setAttribute( 'src', el.getAttribute( 'data-src' ) );
+ }
+ } );
+ }
+
+ }
+
+ /**
+ * "Starts" the content of an embedded iframe using the
+ * postmessage API.
+ */
+ function startEmbeddedIframe( event ) {
+
+ var iframe = event.target;
+
+ // YouTube postMessage API
+ if( /youtube\.com\/embed\//.test( iframe.getAttribute( 'src' ) ) && iframe.hasAttribute( 'data-autoplay' ) ) {
+ iframe.contentWindow.postMessage( '{"event":"command","func":"playVideo","args":""}', '*' );
+ }
+ // Vimeo postMessage API
+ else if( /player\.vimeo\.com\//.test( iframe.getAttribute( 'src' ) ) && iframe.hasAttribute( 'data-autoplay' ) ) {
+ iframe.contentWindow.postMessage( '{"method":"play"}', '*' );
+ }
+ // Generic postMessage API
+ else {
+ iframe.contentWindow.postMessage( 'slide:start', '*' );
+ }
+
+ }
+
+ /**
+ * Stop playback of any embedded content inside of
+ * the targeted slide.
+ */
+ function stopEmbeddedContent( slide ) {
+
+ if( slide && slide.parentNode ) {
+ // HTML5 media elements
+ toArray( slide.querySelectorAll( 'video, audio' ) ).forEach( function( el ) {
+ if( !el.hasAttribute( 'data-ignore' ) && typeof el.pause === 'function' ) {
+ el.pause();
+ }
+ } );
+
+ // Generic postMessage API for non-lazy loaded iframes
+ toArray( slide.querySelectorAll( 'iframe' ) ).forEach( function( el ) {
+ el.contentWindow.postMessage( 'slide:stop', '*' );
+ el.removeEventListener( 'load', startEmbeddedIframe );
+ });
+
+ // YouTube postMessage API
+ toArray( slide.querySelectorAll( 'iframe[src*="youtube.com/embed/"]' ) ).forEach( function( el ) {
+ if( !el.hasAttribute( 'data-ignore' ) && typeof el.contentWindow.postMessage === 'function' ) {
+ el.contentWindow.postMessage( '{"event":"command","func":"pauseVideo","args":""}', '*' );
+ }
+ });
+
+ // Vimeo postMessage API
+ toArray( slide.querySelectorAll( 'iframe[src*="player.vimeo.com/"]' ) ).forEach( function( el ) {
+ if( !el.hasAttribute( 'data-ignore' ) && typeof el.contentWindow.postMessage === 'function' ) {
+ el.contentWindow.postMessage( '{"method":"pause"}', '*' );
+ }
+ });
+
+ // Lazy loading iframes
+ toArray( slide.querySelectorAll( 'iframe[data-src]' ) ).forEach( function( el ) {
+ // Only removing the src doesn't actually unload the frame
+ // in all browsers (Firefox) so we set it to blank first
+ el.setAttribute( 'src', 'about:blank' );
+ el.removeAttribute( 'src' );
+ } );
+ }
+
+ }
+
+ /**
+ * Returns the number of past slides. This can be used as a global
+ * flattened index for slides.
+ */
+ function getSlidePastCount() {
+
+ var horizontalSlides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
+
+ // The number of past slides
+ var pastCount = 0;
+
+ // Step through all slides and count the past ones
+ mainLoop: for( var i = 0; i < horizontalSlides.length; i++ ) {
+
+ var horizontalSlide = horizontalSlides[i];
+ var verticalSlides = toArray( horizontalSlide.querySelectorAll( 'section' ) );
+
+ for( var j = 0; j < verticalSlides.length; j++ ) {
+
+ // Stop as soon as we arrive at the present
+ if( verticalSlides[j].classList.contains( 'present' ) ) {
+ break mainLoop;
+ }
+
+ pastCount++;
+
+ }
+
+ // Stop as soon as we arrive at the present
+ if( horizontalSlide.classList.contains( 'present' ) ) {
+ break;
+ }
+
+ // Don't count the wrapping section for vertical slides
+ if( horizontalSlide.classList.contains( 'stack' ) === false ) {
+ pastCount++;
+ }
+
+ }
+
+ return pastCount;
+
+ }
+
+ /**
+ * Returns a value ranging from 0-1 that represents
+ * how far into the presentation we have navigated.
+ */
+ function getProgress() {
+
+ // The number of past and total slides
+ var totalCount = getTotalSlides();
+ var pastCount = getSlidePastCount();
+
+ if( currentSlide ) {
+
+ var allFragments = currentSlide.querySelectorAll( '.fragment' );
+
+ // If there are fragments in the current slide those should be
+ // accounted for in the progress.
+ if( allFragments.length > 0 ) {
+ var visibleFragments = currentSlide.querySelectorAll( '.fragment.visible' );
+
+ // This value represents how big a portion of the slide progress
+ // that is made up by its fragments (0-1)
+ var fragmentWeight = 0.9;
+
+ // Add fragment progress to the past slide count
+ pastCount += ( visibleFragments.length / allFragments.length ) * fragmentWeight;
+ }
+
+ }
+
+ return pastCount / ( totalCount - 1 );
+
+ }
+
+ /**
+ * Checks if this presentation is running inside of the
+ * speaker notes window.
+ */
+ function isSpeakerNotes() {
+
+ return !!window.location.search.match( /receiver/gi );
+
+ }
+
+ /**
+ * Reads the current URL (hash) and navigates accordingly.
+ */
+ function readURL() {
+
+ var hash = window.location.hash;
+
+ // Attempt to parse the hash as either an index or name
+ var bits = hash.slice( 2 ).split( '/' ),
+ name = hash.replace( /#|\//gi, '' );
+
+ // If the first bit is invalid and there is a name we can
+ // assume that this is a named link
+ if( isNaN( parseInt( bits[0], 10 ) ) && name.length ) {
+ var element;
+
+ // Ensure the named link is a valid HTML ID attribute
+ if( /^[a-zA-Z][\w:.-]*$/.test( name ) ) {
+ // Find the slide with the specified ID
+ element = document.getElementById( name );
+ }
+
+ if( element ) {
+ // Find the position of the named slide and navigate to it
+ var indices = Reveal.getIndices( element );
+ slide( indices.h, indices.v );
+ }
+ // If the slide doesn't exist, navigate to the current slide
+ else {
+ slide( indexh || 0, indexv || 0 );
+ }
+ }
+ else {
+ // Read the index components of the hash
+ var h = parseInt( bits[0], 10 ) || 0,
+ v = parseInt( bits[1], 10 ) || 0;
+
+ if( h !== indexh || v !== indexv ) {
+ slide( h, v );
+ }
+ }
+
+ }
+
+ /**
+ * Updates the page URL (hash) to reflect the current
+ * state.
+ *
+ * @param {Number} delay The time in ms to wait before
+ * writing the hash
+ */
+ function writeURL( delay ) {
+
+ if( config.history ) {
+
+ // Make sure there's never more than one timeout running
+ clearTimeout( writeURLTimeout );
+
+ // If a delay is specified, timeout this call
+ if( typeof delay === 'number' ) {
+ writeURLTimeout = setTimeout( writeURL, delay );
+ }
+ else if( currentSlide ) {
+ var url = '/';
+
+ // Attempt to create a named link based on the slide's ID
+ var id = currentSlide.getAttribute( 'id' );
+ if( id ) {
+ id = id.replace( /[^a-zA-Z0-9\-\_\:\.]/g, '' );
+ }
+
+ // If the current slide has an ID, use that as a named link
+ if( typeof id === 'string' && id.length ) {
+ url = '/' + id;
+ }
+ // Otherwise use the /h/v index
+ else {
+ if( indexh > 0 || indexv > 0 ) url += indexh;
+ if( indexv > 0 ) url += '/' + indexv;
+ }
+
+ window.location.hash = url;
+ }
+ }
+
+ }
+
+ /**
+ * Retrieves the h/v location of the current, or specified,
+ * slide.
+ *
+ * @param {HTMLElement} slide If specified, the returned
+ * index will be for this slide rather than the currently
+ * active one
+ *
+ * @return {Object} { h: <int>, v: <int>, f: <int> }
+ */
+ function getIndices( slide ) {
+
+ // By default, return the current indices
+ var h = indexh,
+ v = indexv,
+ f;
+
+ // If a slide is specified, return the indices of that slide
+ if( slide ) {
+ var isVertical = isVerticalSlide( slide );
+ var slideh = isVertical ? slide.parentNode : slide;
+
+ // Select all horizontal slides
+ var horizontalSlides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
+
+ // Now that we know which the horizontal slide is, get its index
+ h = Math.max( horizontalSlides.indexOf( slideh ), 0 );
+
+ // Assume we're not vertical
+ v = undefined;
+
+ // If this is a vertical slide, grab the vertical index
+ if( isVertical ) {
+ v = Math.max( toArray( slide.parentNode.querySelectorAll( 'section' ) ).indexOf( slide ), 0 );
+ }
+ }
+
+ if( !slide && currentSlide ) {
+ var hasFragments = currentSlide.querySelectorAll( '.fragment' ).length > 0;
+ if( hasFragments ) {
+ var currentFragment = currentSlide.querySelector( '.current-fragment' );
+ if( currentFragment && currentFragment.hasAttribute( 'data-fragment-index' ) ) {
+ f = parseInt( currentFragment.getAttribute( 'data-fragment-index' ), 10 );
+ }
+ else {
+ f = currentSlide.querySelectorAll( '.fragment.visible' ).length - 1;
+ }
+ }
+ }
+
+ return { h: h, v: v, f: f };
+
+ }
+
+ /**
+ * Retrieves the total number of slides in this presentation.
+ */
+ function getTotalSlides() {
+
+ return dom.wrapper.querySelectorAll( SLIDES_SELECTOR + ':not(.stack)' ).length;
+
+ }
+
+ /**
+ * Returns the slide element matching the specified index.
+ */
+ function getSlide( x, y ) {
+
+ var horizontalSlide = dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR )[ x ];
+ var verticalSlides = horizontalSlide && horizontalSlide.querySelectorAll( 'section' );
+
+ if( verticalSlides && verticalSlides.length && typeof y === 'number' ) {
+ return verticalSlides ? verticalSlides[ y ] : undefined;
+ }
+
+ return horizontalSlide;
+
+ }
+
+ /**
+ * Returns the background element for the given slide.
+ * All slides, even the ones with no background properties
+ * defined, have a background element so as long as the
+ * index is valid an element will be returned.
+ */
+ function getSlideBackground( x, y ) {
+
+ // When printing to PDF the slide backgrounds are nested
+ // inside of the slides
+ if( isPrintingPDF() ) {
+ var slide = getSlide( x, y );
+ if( slide ) {
+ var background = slide.querySelector( '.slide-background' );
+ if( background && background.parentNode === slide ) {
+ return background;
+ }
+ }
+
+ return undefined;
+ }
+
+ var horizontalBackground = dom.wrapper.querySelectorAll( '.backgrounds>.slide-background' )[ x ];
+ var verticalBackgrounds = horizontalBackground && horizontalBackground.querySelectorAll( '.slide-background' );
+
+ if( verticalBackgrounds && verticalBackgrounds.length && typeof y === 'number' ) {
+ return verticalBackgrounds ? verticalBackgrounds[ y ] : undefined;
+ }
+
+ return horizontalBackground;
+
+ }
+
+ /**
+ * Retrieves the speaker notes from a slide. Notes can be
+ * defined in two ways:
+ * 1. As a data-notes attribute on the slide <section>
+ * 2. As an <aside class="notes"> inside of the slide
+ */
+ function getSlideNotes( slide ) {
+
+ // Default to the current slide
+ slide = slide || currentSlide;
+
+ // Notes can be specified via the data-notes attribute...
+ if( slide.hasAttribute( 'data-notes' ) ) {
+ return slide.getAttribute( 'data-notes' );
+ }
+
+ // ... or using an <aside class="notes"> element
+ var notesElement = slide.querySelector( 'aside.notes' );
+ if( notesElement ) {
+ return notesElement.innerHTML;
+ }
+
+ return null;
+
+ }
+
+ /**
+ * Retrieves the current state of the presentation as
+ * an object. This state can then be restored at any
+ * time.
+ */
+ function getState() {
+
+ var indices = getIndices();
+
+ return {
+ indexh: indices.h,
+ indexv: indices.v,
+ indexf: indices.f,
+ paused: isPaused(),
+ overview: isOverview()
+ };
+
+ }
+
+ /**
+ * Restores the presentation to the given state.
+ *
+ * @param {Object} state As generated by getState()
+ */
+ function setState( state ) {
+
+ if( typeof state === 'object' ) {
+ slide( deserialize( state.indexh ), deserialize( state.indexv ), deserialize( state.indexf ) );
+
+ var pausedFlag = deserialize( state.paused ),
+ overviewFlag = deserialize( state.overview );
+
+ if( typeof pausedFlag === 'boolean' && pausedFlag !== isPaused() ) {
+ togglePause( pausedFlag );
+ }
+
+ if( typeof overviewFlag === 'boolean' && overviewFlag !== isOverview() ) {
+ toggleOverview( overviewFlag );
+ }
+ }
+
+ }
+
+ /**
+ * Return a sorted fragments list, ordered by an increasing
+ * "data-fragment-index" attribute.
+ *
+ * Fragments will be revealed in the order that they are returned by
+ * this function, so you can use the index attributes to control the
+ * order of fragment appearance.
+ *
+ * To maintain a sensible default fragment order, fragments are presumed
+ * to be passed in document order. This function adds a "fragment-index"
+ * attribute to each node if such an attribute is not already present,
+ * and sets that attribute to an integer value which is the position of
+ * the fragment within the fragments list.
+ */
+ function sortFragments( fragments ) {
+
+ fragments = toArray( fragments );
+
+ var ordered = [],
+ unordered = [],
+ sorted = [];
+
+ // Group ordered and unordered elements
+ fragments.forEach( function( fragment, i ) {
+ if( fragment.hasAttribute( 'data-fragment-index' ) ) {
+ var index = parseInt( fragment.getAttribute( 'data-fragment-index' ), 10 );
+
+ if( !ordered[index] ) {
+ ordered[index] = [];
+ }
+
+ ordered[index].push( fragment );
+ }
+ else {
+ unordered.push( [ fragment ] );
+ }
+ } );
+
+ // Append fragments without explicit indices in their
+ // DOM order
+ ordered = ordered.concat( unordered );
+
+ // Manually count the index up per group to ensure there
+ // are no gaps
+ var index = 0;
+
+ // Push all fragments in their sorted order to an array,
+ // this flattens the groups
+ ordered.forEach( function( group ) {
+ group.forEach( function( fragment ) {
+ sorted.push( fragment );
+ fragment.setAttribute( 'data-fragment-index', index );
+ } );
+
+ index ++;
+ } );
+
+ return sorted;
+
+ }
+
+ /**
+ * Navigate to the specified slide fragment.
+ *
+ * @param {Number} index The index of the fragment that
+ * should be shown, -1 means all are invisible
+ * @param {Number} offset Integer offset to apply to the
+ * fragment index
+ *
+ * @return {Boolean} true if a change was made in any
+ * fragments visibility as part of this call
+ */
+ function navigateFragment( index, offset ) {
+
+ if( currentSlide && config.fragments ) {
+
+ var fragments = sortFragments( currentSlide.querySelectorAll( '.fragment' ) );
+ if( fragments.length ) {
+
+ // If no index is specified, find the current
+ if( typeof index !== 'number' ) {
+ var lastVisibleFragment = sortFragments( currentSlide.querySelectorAll( '.fragment.visible' ) ).pop();
+
+ if( lastVisibleFragment ) {
+ index = parseInt( lastVisibleFragment.getAttribute( 'data-fragment-index' ) || 0, 10 );
+ }
+ else {
+ index = -1;
+ }
+ }
+
+ // If an offset is specified, apply it to the index
+ if( typeof offset === 'number' ) {
+ index += offset;
+ }
+
+ var fragmentsShown = [],
+ fragmentsHidden = [];
+
+ toArray( fragments ).forEach( function( element, i ) {
+
+ if( element.hasAttribute( 'data-fragment-index' ) ) {
+ i = parseInt( element.getAttribute( 'data-fragment-index' ), 10 );
+ }
+
+ // Visible fragments
+ if( i <= index ) {
+ if( !element.classList.contains( 'visible' ) ) fragmentsShown.push( element );
+ element.classList.add( 'visible' );
+ element.classList.remove( 'current-fragment' );
+
+ // Announce the fragments one by one to the Screen Reader
+ dom.statusDiv.textContent = element.textContent;
+
+ if( i === index ) {
+ element.classList.add( 'current-fragment' );
+ }
+ }
+ // Hidden fragments
+ else {
+ if( element.classList.contains( 'visible' ) ) fragmentsHidden.push( element );
+ element.classList.remove( 'visible' );
+ element.classList.remove( 'current-fragment' );
+ }
+
+
+ } );
+
+ if( fragmentsHidden.length ) {
+ dispatchEvent( 'fragmenthidden', { fragment: fragmentsHidden[0], fragments: fragmentsHidden } );
+ }
+
+ if( fragmentsShown.length ) {
+ dispatchEvent( 'fragmentshown', { fragment: fragmentsShown[0], fragments: fragmentsShown } );
+ }
+
+ updateControls();
+ updateProgress();
+
+ return !!( fragmentsShown.length || fragmentsHidden.length );
+
+ }
+
+ }
+
+ return false;
+
+ }
+
+ /**
+ * Navigate to the next slide fragment.
+ *
+ * @return {Boolean} true if there was a next fragment,
+ * false otherwise
+ */
+ function nextFragment() {
+
+ return navigateFragment( null, 1 );
+
+ }
+
+ /**
+ * Navigate to the previous slide fragment.
+ *
+ * @return {Boolean} true if there was a previous fragment,
+ * false otherwise
+ */
+ function previousFragment() {
+
+ return navigateFragment( null, -1 );
+
+ }
+
+ /**
+ * Cues a new automated slide if enabled in the config.
+ */
+ function cueAutoSlide() {
+
+ cancelAutoSlide();
+
+ if( currentSlide ) {
+
+ var currentFragment = currentSlide.querySelector( '.current-fragment' );
+
+ var fragmentAutoSlide = currentFragment ? currentFragment.getAttribute( 'data-autoslide' ) : null;
+ var parentAutoSlide = currentSlide.parentNode ? currentSlide.parentNode.getAttribute( 'data-autoslide' ) : null;
+ var slideAutoSlide = currentSlide.getAttribute( 'data-autoslide' );
+
+ // Pick value in the following priority order:
+ // 1. Current fragment's data-autoslide
+ // 2. Current slide's data-autoslide
+ // 3. Parent slide's data-autoslide
+ // 4. Global autoSlide setting
+ if( fragmentAutoSlide ) {
+ autoSlide = parseInt( fragmentAutoSlide, 10 );
+ }
+ else if( slideAutoSlide ) {
+ autoSlide = parseInt( slideAutoSlide, 10 );
+ }
+ else if( parentAutoSlide ) {
+ autoSlide = parseInt( parentAutoSlide, 10 );
+ }
+ else {
+ autoSlide = config.autoSlide;
+ }
+
+ // If there are media elements with data-autoplay,
+ // automatically set the autoSlide duration to the
+ // length of that media. Not applicable if the slide
+ // is divided up into fragments.
+ if( currentSlide.querySelectorAll( '.fragment' ).length === 0 ) {
+ toArray( currentSlide.querySelectorAll( 'video, audio' ) ).forEach( function( el ) {
+ if( el.hasAttribute( 'data-autoplay' ) ) {
+ if( autoSlide && el.duration * 1000 > autoSlide ) {
+ autoSlide = ( el.duration * 1000 ) + 1000;
+ }
+ }
+ } );
+ }
+
+ // Cue the next auto-slide if:
+ // - There is an autoSlide value
+ // - Auto-sliding isn't paused by the user
+ // - The presentation isn't paused
+ // - The overview isn't active
+ // - The presentation isn't over
+ if( autoSlide && !autoSlidePaused && !isPaused() && !isOverview() && ( !Reveal.isLastSlide() || availableFragments().next || config.loop === true ) ) {
+ autoSlideTimeout = setTimeout( function() {
+ typeof config.autoSlideMethod === 'function' ? config.autoSlideMethod() : navigateNext();
+ cueAutoSlide();
+ }, autoSlide );
+ autoSlideStartTime = Date.now();
+ }
+
+ if( autoSlidePlayer ) {
+ autoSlidePlayer.setPlaying( autoSlideTimeout !== -1 );
+ }
+
+ }
+
+ }
+
+ /**
+ * Cancels any ongoing request to auto-slide.
+ */
+ function cancelAutoSlide() {
+
+ clearTimeout( autoSlideTimeout );
+ autoSlideTimeout = -1;
+
+ }
+
+ function pauseAutoSlide() {
+
+ if( autoSlide && !autoSlidePaused ) {
+ autoSlidePaused = true;
+ dispatchEvent( 'autoslidepaused' );
+ clearTimeout( autoSlideTimeout );
+
+ if( autoSlidePlayer ) {
+ autoSlidePlayer.setPlaying( false );
+ }
+ }
+
+ }
+
+ function resumeAutoSlide() {
+
+ if( autoSlide && autoSlidePaused ) {
+ autoSlidePaused = false;
+ dispatchEvent( 'autoslideresumed' );
+ cueAutoSlide();
+ }
+
+ }
+
+ function navigateLeft() {
+
+ // Reverse for RTL
+ if( config.rtl ) {
+ if( ( isOverview() || nextFragment() === false ) && availableRoutes().left ) {
+ slide( indexh + 1 );
+ }
+ }
+ // Normal navigation
+ else if( ( isOverview() || previousFragment() === false ) && availableRoutes().left ) {
+ slide( indexh - 1 );
+ }
+
+ }
+
+ function navigateRight() {
+
+ // Reverse for RTL
+ if( config.rtl ) {
+ if( ( isOverview() || previousFragment() === false ) && availableRoutes().right ) {
+ slide( indexh - 1 );
+ }
+ }
+ // Normal navigation
+ else if( ( isOverview() || nextFragment() === false ) && availableRoutes().right ) {
+ slide( indexh + 1 );
+ }
+
+ }
+
+ function navigateUp() {
+
+ // Prioritize hiding fragments
+ if( ( isOverview() || previousFragment() === false ) && availableRoutes().up ) {
+ slide( indexh, indexv - 1 );
+ }
+
+ }
+
+ function navigateDown() {
+
+ // Prioritize revealing fragments
+ if( ( isOverview() || nextFragment() === false ) && availableRoutes().down ) {
+ slide( indexh, indexv + 1 );
+ }
+
+ }
+
+ /**
+ * Navigates backwards, prioritized in the following order:
+ * 1) Previous fragment
+ * 2) Previous vertical slide
+ * 3) Previous horizontal slide
+ */
+ function navigatePrev() {
+
+ // Prioritize revealing fragments
+ if( previousFragment() === false ) {
+ if( availableRoutes().up ) {
+ navigateUp();
+ }
+ else {
+ // Fetch the previous horizontal slide, if there is one
+ var previousSlide;
+
+ if( config.rtl ) {
+ previousSlide = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.future' ) ).pop();
+ }
+ else {
+ previousSlide = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.past' ) ).pop();
+ }
+
+ if( previousSlide ) {
+ var v = ( previousSlide.querySelectorAll( 'section' ).length - 1 ) || undefined;
+ var h = indexh - 1;
+ slide( h, v );
+ }
+ }
+ }
+
+ }
+
+ /**
+ * The reverse of #navigatePrev().
+ */
+ function navigateNext() {
+
+ // Prioritize revealing fragments
+ if( nextFragment() === false ) {
+ if( availableRoutes().down ) {
+ navigateDown();
+ }
+ else if( config.rtl ) {
+ navigateLeft();
+ }
+ else {
+ navigateRight();
+ }
+ }
+
+ }
+
+ /**
+ * Checks if the target element prevents the triggering of
+ * swipe navigation.
+ */
+ function isSwipePrevented( target ) {
+
+ while( target && typeof target.hasAttribute === 'function' ) {
+ if( target.hasAttribute( 'data-prevent-swipe' ) ) return true;
+ target = target.parentNode;
+ }
+
+ return false;
+
+ }
+
+
+ // --------------------------------------------------------------------//
+ // ----------------------------- EVENTS -------------------------------//
+ // --------------------------------------------------------------------//
+
+ /**
+ * Called by all event handlers that are based on user
+ * input.
+ */
+ function onUserInput( event ) {
+
+ if( config.autoSlideStoppable ) {
+ pauseAutoSlide();
+ }
+
+ }
+
+ /**
+ * Handler for the document level 'keypress' event.
+ */
+ function onDocumentKeyPress( event ) {
+
+ // Check if the pressed key is question mark
+ if( event.shiftKey && event.charCode === 63 ) {
+ if( dom.overlay ) {
+ closeOverlay();
+ }
+ else {
+ showHelp( true );
+ }
+ }
+
+ }
+
+ /**
+ * Handler for the document level 'keydown' event.
+ */
+ function onDocumentKeyDown( event ) {
+
+ // If there's a condition specified and it returns false,
+ // ignore this event
+ if( typeof config.keyboardCondition === 'function' && config.keyboardCondition() === false ) {
+ return true;
+ }
+
+ // Remember if auto-sliding was paused so we can toggle it
+ var autoSlideWasPaused = autoSlidePaused;
+
+ onUserInput( event );
+
+ // Check if there's a focused element that could be using
+ // the keyboard
+ var activeElementIsCE = document.activeElement && document.activeElement.contentEditable !== 'inherit';
+ var activeElementIsInput = document.activeElement && document.activeElement.tagName && /input|textarea/i.test( document.activeElement.tagName );
+
+ // Disregard the event if there's a focused element or a
+ // keyboard modifier key is present
+ if( activeElementIsCE || activeElementIsInput || (event.shiftKey && event.keyCode !== 32) || event.altKey || event.ctrlKey || event.metaKey ) return;
+
+ // While paused only allow resume keyboard events; 'b', '.''
+ var resumeKeyCodes = [66,190,191];
+ var key;
+
+ // Custom key bindings for togglePause should be able to resume
+ if( typeof config.keyboard === 'object' ) {
+ for( key in config.keyboard ) {
+ if( config.keyboard[key] === 'togglePause' ) {
+ resumeKeyCodes.push( parseInt( key, 10 ) );
+ }
+ }
+ }
+
+ if( isPaused() && resumeKeyCodes.indexOf( event.keyCode ) === -1 ) {
+ return false;
+ }
+
+ var triggered = false;
+
+ // 1. User defined key bindings
+ if( typeof config.keyboard === 'object' ) {
+
+ for( key in config.keyboard ) {
+
+ // Check if this binding matches the pressed key
+ if( parseInt( key, 10 ) === event.keyCode ) {
+
+ var value = config.keyboard[ key ];
+
+ // Callback function
+ if( typeof value === 'function' ) {
+ value.apply( null, [ event ] );
+ }
+ // String shortcuts to reveal.js API
+ else if( typeof value === 'string' && typeof Reveal[ value ] === 'function' ) {
+ Reveal[ value ].call();
+ }
+
+ triggered = true;
+
+ }
+
+ }
+
+ }
+
+ // 2. System defined key bindings
+ if( triggered === false ) {
+
+ // Assume true and try to prove false
+ triggered = true;
+
+ switch( event.keyCode ) {
+ // p, page up
+ case 80: case 33: navigatePrev(); break;
+ // n, page down
+ case 78: case 34: navigateNext(); break;
+ // h, left
+ case 72: case 37: navigateLeft(); break;
+ // l, right
+ case 76: case 39: navigateRight(); break;
+ // k, up
+ case 75: case 38: navigateUp(); break;
+ // j, down
+ case 74: case 40: navigateDown(); break;
+ // home
+ case 36: slide( 0 ); break;
+ // end
+ case 35: slide( Number.MAX_VALUE ); break;
+ // space
+ case 32: isOverview() ? deactivateOverview() : event.shiftKey ? navigatePrev() : navigateNext(); break;
+ // return
+ case 13: isOverview() ? deactivateOverview() : triggered = false; break;
+ // two-spot, semicolon, b, period, Logitech presenter tools "black screen" button
+ case 58: case 59: case 66: case 190: case 191: togglePause(); break;
+ // f
+ case 70: enterFullscreen(); break;
+ // a
+ case 65: if ( config.autoSlideStoppable ) toggleAutoSlide( autoSlideWasPaused ); break;
+ default:
+ triggered = false;
+ }
+
+ }
+
+ // If the input resulted in a triggered action we should prevent
+ // the browsers default behavior
+ if( triggered ) {
+ event.preventDefault && event.preventDefault();
+ }
+ // ESC or O key
+ else if ( ( event.keyCode === 27 || event.keyCode === 79 ) && features.transforms3d ) {
+ if( dom.overlay ) {
+ closeOverlay();
+ }
+ else {
+ toggleOverview();
+ }
+
+ event.preventDefault && event.preventDefault();
+ }
+
+ // If auto-sliding is enabled we need to cue up
+ // another timeout
+ cueAutoSlide();
+
+ }
+
+ /**
+ * Handler for the 'touchstart' event, enables support for
+ * swipe and pinch gestures.
+ */
+ function onTouchStart( event ) {
+
+ if( isSwipePrevented( event.target ) ) return true;
+
+ touch.startX = event.touches[0].clientX;
+ touch.startY = event.touches[0].clientY;
+ touch.startCount = event.touches.length;
+
+ // If there's two touches we need to memorize the distance
+ // between those two points to detect pinching
+ if( event.touches.length === 2 && config.overview ) {
+ touch.startSpan = distanceBetween( {
+ x: event.touches[1].clientX,
+ y: event.touches[1].clientY
+ }, {
+ x: touch.startX,
+ y: touch.startY
+ } );
+ }
+
+ }
+
+ /**
+ * Handler for the 'touchmove' event.
+ */
+ function onTouchMove( event ) {
+
+ if( isSwipePrevented( event.target ) ) return true;
+
+ // Each touch should only trigger one action
+ if( !touch.captured ) {
+ onUserInput( event );
+
+ var currentX = event.touches[0].clientX;
+ var currentY = event.touches[0].clientY;
+
+ // If the touch started with two points and still has
+ // two active touches; test for the pinch gesture
+ if( event.touches.length === 2 && touch.startCount === 2 && config.overview ) {
+
+ // The current distance in pixels between the two touch points
+ var currentSpan = distanceBetween( {
+ x: event.touches[1].clientX,
+ y: event.touches[1].clientY
+ }, {
+ x: touch.startX,
+ y: touch.startY
+ } );
+
+ // If the span is larger than the desire amount we've got
+ // ourselves a pinch
+ if( Math.abs( touch.startSpan - currentSpan ) > touch.threshold ) {
+ touch.captured = true;
+
+ if( currentSpan < touch.startSpan ) {
+ activateOverview();
+ }
+ else {
+ deactivateOverview();
+ }
+ }
+
+ event.preventDefault();
+
+ }
+ // There was only one touch point, look for a swipe
+ else if( event.touches.length === 1 && touch.startCount !== 2 ) {
+
+ var deltaX = currentX - touch.startX,
+ deltaY = currentY - touch.startY;
+
+ if( deltaX > touch.threshold && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
+ touch.captured = true;
+ navigateLeft();
+ }
+ else if( deltaX < -touch.threshold && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
+ touch.captured = true;
+ navigateRight();
+ }
+ else if( deltaY > touch.threshold ) {
+ touch.captured = true;
+ navigateUp();
+ }
+ else if( deltaY < -touch.threshold ) {
+ touch.captured = true;
+ navigateDown();
+ }
+
+ // If we're embedded, only block touch events if they have
+ // triggered an action
+ if( config.embedded ) {
+ if( touch.captured || isVerticalSlide( currentSlide ) ) {
+ event.preventDefault();
+ }
+ }
+ // Not embedded? Block them all to avoid needless tossing
+ // around of the viewport in iOS
+ else {
+ event.preventDefault();
+ }
+
+ }
+ }
+ // There's a bug with swiping on some Android devices unless
+ // the default action is always prevented
+ else if( UA.match( /android/gi ) ) {
+ event.preventDefault();
+ }
+
+ }
+
+ /**
+ * Handler for the 'touchend' event.
+ */
+ function onTouchEnd( event ) {
+
+ touch.captured = false;
+
+ }
+
+ /**
+ * Convert pointer down to touch start.
+ */
+ function onPointerDown( event ) {
+
+ if( event.pointerType === event.MSPOINTER_TYPE_TOUCH || event.pointerType === "touch" ) {
+ event.touches = [{ clientX: event.clientX, clientY: event.clientY }];
+ onTouchStart( event );
+ }
+
+ }
+
+ /**
+ * Convert pointer move to touch move.
+ */
+ function onPointerMove( event ) {
+
+ if( event.pointerType === event.MSPOINTER_TYPE_TOUCH || event.pointerType === "touch" ) {
+ event.touches = [{ clientX: event.clientX, clientY: event.clientY }];
+ onTouchMove( event );
+ }
+
+ }
+
+ /**
+ * Convert pointer up to touch end.
+ */
+ function onPointerUp( event ) {
+
+ if( event.pointerType === event.MSPOINTER_TYPE_TOUCH || event.pointerType === "touch" ) {
+ event.touches = [{ clientX: event.clientX, clientY: event.clientY }];
+ onTouchEnd( event );
+ }
+
+ }
+
+ /**
+ * Handles mouse wheel scrolling, throttled to avoid skipping
+ * multiple slides.
+ */
+ function onDocumentMouseScroll( event ) {
+
+ if( Date.now() - lastMouseWheelStep > 600 ) {
+
+ lastMouseWheelStep = Date.now();
+
+ var delta = event.detail || -event.wheelDelta;
+ if( delta > 0 ) {
+ navigateNext();
+ }
+ else {
+ navigatePrev();
+ }
+
+ }
+
+ }
+
+ /**
+ * Clicking on the progress bar results in a navigation to the
+ * closest approximate horizontal slide using this equation:
+ *
+ * ( clickX / presentationWidth ) * numberOfSlides
+ */
+ function onProgressClicked( event ) {
+
+ onUserInput( event );
+
+ event.preventDefault();
+
+ var slidesTotal = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).length;
+ var slideIndex = Math.floor( ( event.clientX / dom.wrapper.offsetWidth ) * slidesTotal );
+
+ if( config.rtl ) {
+ slideIndex = slidesTotal - slideIndex;
+ }
+
+ slide( slideIndex );
+
+ }
+
+ /**
+ * Event handler for navigation control buttons.
+ */
+ function onNavigateLeftClicked( event ) { event.preventDefault(); onUserInput(); navigateLeft(); }
+ function onNavigateRightClicked( event ) { event.preventDefault(); onUserInput(); navigateRight(); }
+ function onNavigateUpClicked( event ) { event.preventDefault(); onUserInput(); navigateUp(); }
+ function onNavigateDownClicked( event ) { event.preventDefault(); onUserInput(); navigateDown(); }
+ function onNavigatePrevClicked( event ) { event.preventDefault(); onUserInput(); navigatePrev(); }
+ function onNavigateNextClicked( event ) { event.preventDefault(); onUserInput(); navigateNext(); }
+
+ /**
+ * Handler for the window level 'hashchange' event.
+ */
+ function onWindowHashChange( event ) {
+
+ readURL();
+
+ }
+
+ /**
+ * Handler for the window level 'resize' event.
+ */
+ function onWindowResize( event ) {
+
+ layout();
+
+ }
+
+ /**
+ * Handle for the window level 'visibilitychange' event.
+ */
+ function onPageVisibilityChange( event ) {
+
+ var isHidden = document.webkitHidden ||
+ document.msHidden ||
+ document.hidden;
+
+ // If, after clicking a link or similar and we're coming back,
+ // focus the document.body to ensure we can use keyboard shortcuts
+ if( isHidden === false && document.activeElement !== document.body ) {
+ // Not all elements support .blur() - SVGs among them.
+ if( typeof document.activeElement.blur === 'function' ) {
+ document.activeElement.blur();
+ }
+ document.body.focus();
+ }
+
+ }
+
+ /**
+ * Invoked when a slide is and we're in the overview.
+ */
+ function onOverviewSlideClicked( event ) {
+
+ // TODO There's a bug here where the event listeners are not
+ // removed after deactivating the overview.
+ if( eventsAreBound && isOverview() ) {
+ event.preventDefault();
+
+ var element = event.target;
+
+ while( element && !element.nodeName.match( /section/gi ) ) {
+ element = element.parentNode;
+ }
+
+ if( element && !element.classList.contains( 'disabled' ) ) {
+
+ deactivateOverview();
+
+ if( element.nodeName.match( /section/gi ) ) {
+ var h = parseInt( element.getAttribute( 'data-index-h' ), 10 ),
+ v = parseInt( element.getAttribute( 'data-index-v' ), 10 );
+
+ slide( h, v );
+ }
+
+ }
+ }
+
+ }
+
+ /**
+ * Handles clicks on links that are set to preview in the
+ * iframe overlay.
+ */
+ function onPreviewLinkClicked( event ) {
+
+ if( event.currentTarget && event.currentTarget.hasAttribute( 'href' ) ) {
+ var url = event.currentTarget.getAttribute( 'href' );
+ if( url ) {
+ showPreview( url );
+ event.preventDefault();
+ }
+ }
+
+ }
+
+ /**
+ * Handles click on the auto-sliding controls element.
+ */
+ function onAutoSlidePlayerClick( event ) {
+
+ // Replay
+ if( Reveal.isLastSlide() && config.loop === false ) {
+ slide( 0, 0 );
+ resumeAutoSlide();
+ }
+ // Resume
+ else if( autoSlidePaused ) {
+ resumeAutoSlide();
+ }
+ // Pause
+ else {
+ pauseAutoSlide();
+ }
+
+ }
+
+
+ // --------------------------------------------------------------------//
+ // ------------------------ PLAYBACK COMPONENT ------------------------//
+ // --------------------------------------------------------------------//
+
+
+ /**
+ * Constructor for the playback component, which displays
+ * play/pause/progress controls.
+ *
+ * @param {HTMLElement} container The component will append
+ * itself to this
+ * @param {Function} progressCheck A method which will be
+ * called frequently to get the current progress on a range
+ * of 0-1
+ */
+ function Playback( container, progressCheck ) {
+
+ // Cosmetics
+ this.diameter = 100;
+ this.diameter2 = this.diameter/2;
+ this.thickness = 6;
+
+ // Flags if we are currently playing
+ this.playing = false;
+
+ // Current progress on a 0-1 range
+ this.progress = 0;
+
+ // Used to loop the animation smoothly
+ this.progressOffset = 1;
+
+ this.container = container;
+ this.progressCheck = progressCheck;
+
+ this.canvas = document.createElement( 'canvas' );
+ this.canvas.className = 'playback';
+ this.canvas.width = this.diameter;
+ this.canvas.height = this.diameter;
+ this.canvas.style.width = this.diameter2 + 'px';
+ this.canvas.style.height = this.diameter2 + 'px';
+ this.context = this.canvas.getContext( '2d' );
+
+ this.container.appendChild( this.canvas );
+
+ this.render();
+
+ }
+
+ Playback.prototype.setPlaying = function( value ) {
+
+ var wasPlaying = this.playing;
+
+ this.playing = value;
+
+ // Start repainting if we weren't already
+ if( !wasPlaying && this.playing ) {
+ this.animate();
+ }
+ else {
+ this.render();
+ }
+
+ };
+
+ Playback.prototype.animate = function() {
+
+ var progressBefore = this.progress;
+
+ this.progress = this.progressCheck();
+
+ // When we loop, offset the progress so that it eases
+ // smoothly rather than immediately resetting
+ if( progressBefore > 0.8 && this.progress < 0.2 ) {
+ this.progressOffset = this.progress;
+ }
+
+ this.render();
+
+ if( this.playing ) {
+ features.requestAnimationFrameMethod.call( window, this.animate.bind( this ) );
+ }
+
+ };
+
+ /**
+ * Renders the current progress and playback state.
+ */
+ Playback.prototype.render = function() {
+
+ var progress = this.playing ? this.progress : 0,
+ radius = ( this.diameter2 ) - this.thickness,
+ x = this.diameter2,
+ y = this.diameter2,
+ iconSize = 28;
+
+ // Ease towards 1
+ this.progressOffset += ( 1 - this.progressOffset ) * 0.1;
+
+ var endAngle = ( - Math.PI / 2 ) + ( progress * ( Math.PI * 2 ) );
+ var startAngle = ( - Math.PI / 2 ) + ( this.progressOffset * ( Math.PI * 2 ) );
+
+ this.context.save();
+ this.context.clearRect( 0, 0, this.diameter, this.diameter );
+
+ // Solid background color
+ this.context.beginPath();
+ this.context.arc( x, y, radius + 4, 0, Math.PI * 2, false );
+ this.context.fillStyle = 'rgba( 0, 0, 0, 0.4 )';
+ this.context.fill();
+
+ // Draw progress track
+ this.context.beginPath();
+ this.context.arc( x, y, radius, 0, Math.PI * 2, false );
+ this.context.lineWidth = this.thickness;
+ this.context.strokeStyle = '#666';
+ this.context.stroke();
+
+ if( this.playing ) {
+ // Draw progress on top of track
+ this.context.beginPath();
+ this.context.arc( x, y, radius, startAngle, endAngle, false );
+ this.context.lineWidth = this.thickness;
+ this.context.strokeStyle = '#fff';
+ this.context.stroke();
+ }
+
+ this.context.translate( x - ( iconSize / 2 ), y - ( iconSize / 2 ) );
+
+ // Draw play/pause icons
+ if( this.playing ) {
+ this.context.fillStyle = '#fff';
+ this.context.fillRect( 0, 0, iconSize / 2 - 4, iconSize );
+ this.context.fillRect( iconSize / 2 + 4, 0, iconSize / 2 - 4, iconSize );
+ }
+ else {
+ this.context.beginPath();
+ this.context.translate( 4, 0 );
+ this.context.moveTo( 0, 0 );
+ this.context.lineTo( iconSize - 4, iconSize / 2 );
+ this.context.lineTo( 0, iconSize );
+ this.context.fillStyle = '#fff';
+ this.context.fill();
+ }
+
+ this.context.restore();
+
+ };
+
+ Playback.prototype.on = function( type, listener ) {
+ this.canvas.addEventListener( type, listener, false );
+ };
+
+ Playback.prototype.off = function( type, listener ) {
+ this.canvas.removeEventListener( type, listener, false );
+ };
+
+ Playback.prototype.destroy = function() {
+
+ this.playing = false;
+
+ if( this.canvas.parentNode ) {
+ this.container.removeChild( this.canvas );
+ }
+
+ };
+
+
+ // --------------------------------------------------------------------//
+ // ------------------------------- API --------------------------------//
+ // --------------------------------------------------------------------//
+
+
+ Reveal = {
+ VERSION: VERSION,
+
+ initialize: initialize,
+ configure: configure,
+ sync: sync,
+
+ // Navigation methods
+ slide: slide,
+ left: navigateLeft,
+ right: navigateRight,
+ up: navigateUp,
+ down: navigateDown,
+ prev: navigatePrev,
+ next: navigateNext,
+
+ // Fragment methods
+ navigateFragment: navigateFragment,
+ prevFragment: previousFragment,
+ nextFragment: nextFragment,
+
+ // Deprecated aliases
+ navigateTo: slide,
+ navigateLeft: navigateLeft,
+ navigateRight: navigateRight,
+ navigateUp: navigateUp,
+ navigateDown: navigateDown,
+ navigatePrev: navigatePrev,
+ navigateNext: navigateNext,
+
+ // Forces an update in slide layout
+ layout: layout,
+
+ // Randomizes the order of slides
+ shuffle: shuffle,
+
+ // Returns an object with the available routes as booleans (left/right/top/bottom)
+ availableRoutes: availableRoutes,
+
+ // Returns an object with the available fragments as booleans (prev/next)
+ availableFragments: availableFragments,
+
+ // Toggles the overview mode on/off
+ toggleOverview: toggleOverview,
+
+ // Toggles the "black screen" mode on/off
+ togglePause: togglePause,
+
+ // Toggles the auto slide mode on/off
+ toggleAutoSlide: toggleAutoSlide,
+
+ // State checks
+ isOverview: isOverview,
+ isPaused: isPaused,
+ isAutoSliding: isAutoSliding,
+
+ // Adds or removes all internal event listeners (such as keyboard)
+ addEventListeners: addEventListeners,
+ removeEventListeners: removeEventListeners,
+
+ // Facility for persisting and restoring the presentation state
+ getState: getState,
+ setState: setState,
+
+ // Presentation progress on range of 0-1
+ getProgress: getProgress,
+
+ // Returns the indices of the current, or specified, slide
+ getIndices: getIndices,
+
+ getTotalSlides: getTotalSlides,
+
+ // Returns the slide element at the specified index
+ getSlide: getSlide,
+
+ // Returns the slide background element at the specified index
+ getSlideBackground: getSlideBackground,
+
+ // Returns the speaker notes string for a slide, or null
+ getSlideNotes: getSlideNotes,
+
+ // Returns the previous slide element, may be null
+ getPreviousSlide: function() {
+ return previousSlide;
+ },
+
+ // Returns the current slide element
+ getCurrentSlide: function() {
+ return currentSlide;
+ },
+
+ // Returns the current scale of the presentation content
+ getScale: function() {
+ return scale;
+ },
+
+ // Returns the current configuration object
+ getConfig: function() {
+ return config;
+ },
+
+ // Helper method, retrieves query string as a key/value hash
+ getQueryHash: function() {
+ var query = {};
+
+ location.search.replace( /[A-Z0-9]+?=([\w\.%-]*)/gi, function(a) {
+ query[ a.split( '=' ).shift() ] = a.split( '=' ).pop();
+ } );
+
+ // Basic deserialization
+ for( var i in query ) {
+ var value = query[ i ];
+
+ query[ i ] = deserialize( unescape( value ) );
+ }
+
+ return query;
+ },
+
+ // Returns true if we're currently on the first slide
+ isFirstSlide: function() {
+ return ( indexh === 0 && indexv === 0 );
+ },
+
+ // Returns true if we're currently on the last slide
+ isLastSlide: function() {
+ if( currentSlide ) {
+ // Does this slide has next a sibling?
+ if( currentSlide.nextElementSibling ) return false;
+
+ // If it's vertical, does its parent have a next sibling?
+ if( isVerticalSlide( currentSlide ) && currentSlide.parentNode.nextElementSibling ) return false;
+
+ return true;
+ }
+
+ return false;
+ },
+
+ // Checks if reveal.js has been loaded and is ready for use
+ isReady: function() {
+ return loaded;
+ },
+
+ // Forward event binding to the reveal DOM element
+ addEventListener: function( type, listener, useCapture ) {
+ if( 'addEventListener' in window ) {
+ ( dom.wrapper || document.querySelector( '.reveal' ) ).addEventListener( type, listener, useCapture );
+ }
+ },
+ removeEventListener: function( type, listener, useCapture ) {
+ if( 'addEventListener' in window ) {
+ ( dom.wrapper || document.querySelector( '.reveal' ) ).removeEventListener( type, listener, useCapture );
+ }
+ },
+
+ // Programatically triggers a keyboard event
+ triggerKey: function( keyCode ) {
+ onDocumentKeyDown( { keyCode: keyCode } );
+ },
+
+ // Registers a new shortcut to include in the help overlay
+ registerKeyboardShortcut: function( key, value ) {
+ keyboardShortcuts[key] = value;
+ }
+ };
+
+ return Reveal;
+
+}));