rc-web@42: /*!
rc-web@42:  * reveal.js 2.0 r22
rc-web@42:  * http://lab.hakim.se/reveal-js
rc-web@42:  * MIT licensed
rc-web@42:  * 
rc-web@42:  * Copyright (C) 2011-2012 Hakim El Hattab, http://hakim.se
rc-web@42:  */
rc-web@42: var Reveal = (function(){
rc-web@42: 	
rc-web@42: 	var HORIZONTAL_SLIDES_SELECTOR = '.reveal .slides>section',
rc-web@42: 		VERTICAL_SLIDES_SELECTOR = '.reveal .slides>section.present>section',
rc-web@42: 
rc-web@42: 		IS_TOUCH_DEVICE = !!( 'ontouchstart' in window ),
rc-web@42: 
rc-web@42: 		// Configurations defaults, can be overridden at initialization time 
rc-web@42: 		config = {
rc-web@42: 			// Display controls in the bottom right corner
rc-web@42: 			controls: true,
rc-web@42: 
rc-web@42: 			// Display a presentation progress bar
rc-web@42: 			progress: true,
rc-web@42: 
rc-web@42: 			// Push each slide change to the browser history
rc-web@42: 			history: false,
rc-web@42: 
rc-web@42: 			// Enable keyboard shortcuts for navigation
rc-web@42: 			keyboard: true,
rc-web@42: 
rc-web@42: 			// Loop the presentation
rc-web@42: 			loop: false,
rc-web@42: 
rc-web@42: 			// Number of milliseconds between automatically proceeding to the 
rc-web@42: 			// next slide, disabled when set to 0
rc-web@42: 			autoSlide: 0,
rc-web@42: 
rc-web@42: 			// Enable slide navigation via mouse wheel
rc-web@42: 			mouseWheel: true,
rc-web@42: 
rc-web@42: 			// Apply a 3D roll to links on hover
rc-web@42: 			rollingLinks: true,
rc-web@42: 
rc-web@42: 			// Transition style (see /css/theme)
rc-web@42: 			theme: 'default', 
rc-web@42: 
rc-web@42: 			// Transition style
rc-web@42: 			transition: 'default', // default/cube/page/concave/linear(2d),
rc-web@42: 
rc-web@42: 			// Script dependencies to load
rc-web@42: 			dependencies: []
rc-web@42: 		},
rc-web@42: 
rc-web@42: 		// The horizontal and verical index of the currently active slide
rc-web@42: 		indexh = 0,
rc-web@42: 		indexv = 0,
rc-web@42: 
rc-web@42: 		// The previous and current slide HTML elements
rc-web@42: 		previousSlide,
rc-web@42: 		currentSlide,
rc-web@42: 
rc-web@42: 		// Slides may hold a data-state attribute which we pick up and apply 
rc-web@42: 		// as a class to the body. This list contains the combined state of 
rc-web@42: 		// all current slides.
rc-web@42: 		state = [],
rc-web@42: 
rc-web@42: 		// Cached references to DOM elements
rc-web@42: 		dom = {},
rc-web@42: 
rc-web@42: 		// Detect support for CSS 3D transforms
rc-web@42: 		supports3DTransforms =  'WebkitPerspective' in document.body.style ||
rc-web@42:                         		'MozPerspective' in document.body.style ||
rc-web@42:                         		'msPerspective' in document.body.style ||
rc-web@42:                         		'OPerspective' in document.body.style ||
rc-web@42:                         		'perspective' in document.body.style,
rc-web@42:         
rc-web@42:         supports2DTransforms =  'WebkitTransform' in document.body.style ||
rc-web@42:                         		'MozTransform' in document.body.style ||
rc-web@42:                         		'msTransform' in document.body.style ||
rc-web@42:                         		'OTransform' in document.body.style ||
rc-web@42:                         		'transform' in document.body.style,
rc-web@42: 		
rc-web@42: 		// Throttles mouse wheel navigation
rc-web@42: 		mouseWheelTimeout = 0,
rc-web@42: 
rc-web@42: 		// An interval used to automatically move on to the next slide
rc-web@42: 		autoSlideTimeout = 0,
rc-web@42: 
rc-web@42: 		// Delays updates to the URL due to a Chrome thumbnailer bug
rc-web@42: 		writeURLTimeout = 0,
rc-web@42: 
rc-web@42: 		// Holds information about the currently ongoing touch input
rc-web@42: 		touch = {
rc-web@42: 			startX: 0,
rc-web@42: 			startY: 0,
rc-web@42: 			startSpan: 0,
rc-web@42: 			startCount: 0,
rc-web@42: 			handled: false,
rc-web@42: 			threshold: 40
rc-web@42: 		};
rc-web@42: 	
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Starts up the presentation if the client is capable.
rc-web@42: 	 */
rc-web@42: 	function initialize( options ) {
rc-web@42: 		if( ( !supports2DTransforms && !supports3DTransforms ) ) {
rc-web@42: 			document.body.setAttribute( 'class', 'no-transforms' );
rc-web@42: 
rc-web@42: 			// If the browser doesn't support core features we won't be 
rc-web@42: 			// using JavaScript to control the presentation
rc-web@42: 			return;
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// Copy options over to our config object
rc-web@42: 		extend( config, options );
rc-web@42: 
rc-web@42: 		// Cache references to DOM elements
rc-web@42: 		dom.theme = document.querySelector( '#theme' );
rc-web@42: 		dom.wrapper = document.querySelector( '.reveal' );
rc-web@42: 		dom.progress = document.querySelector( '.reveal .progress' );
rc-web@42: 		dom.progressbar = document.querySelector( '.reveal .progress span' );
rc-web@42: 
rc-web@42: 		if ( config.controls ) {
rc-web@42: 			dom.controls = document.querySelector( '.reveal .controls' );
rc-web@42: 			dom.controlsLeft = document.querySelector( '.reveal .controls .left' );
rc-web@42: 			dom.controlsRight = document.querySelector( '.reveal .controls .right' );
rc-web@42: 			dom.controlsUp = document.querySelector( '.reveal .controls .up' );
rc-web@42: 			dom.controlsDown = document.querySelector( '.reveal .controls .down' );
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// Loads the dependencies and continues to #start() once done
rc-web@42: 		load();
rc-web@42: 
rc-web@42: 		// Set up hiding of the browser address bar
rc-web@42: 		if( navigator.userAgent.match( /(iphone|ipod|android)/i ) ) {
rc-web@42: 			// Give the page some scrollable overflow
rc-web@42: 			document.documentElement.style.overflow = 'scroll';
rc-web@42: 			document.body.style.height = '120%';
rc-web@42: 
rc-web@42: 			// Events that should trigger the address bar to hide
rc-web@42: 			window.addEventListener( 'load', removeAddressBar, false );
rc-web@42: 			window.addEventListener( 'orientationchange', removeAddressBar, false );
rc-web@42: 		}
rc-web@42: 		
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Loads the dependencies of reveal.js. Dependencies are 
rc-web@42: 	 * defined via the configuration option 'dependencies' 
rc-web@42: 	 * and will be loaded prior to starting/binding reveal.js. 
rc-web@42: 	 * Some dependencies may have an 'async' flag, if so they 
rc-web@42: 	 * will load after reveal.js has been started up.
rc-web@42: 	 */
rc-web@42: 	function load() {
rc-web@42: 		var scripts = [],
rc-web@42: 			scriptsAsync = [];
rc-web@42: 
rc-web@42: 		for( var i = 0, len = config.dependencies.length; i < len; i++ ) {
rc-web@42: 			var s = config.dependencies[i];
rc-web@42: 
rc-web@42: 			// Load if there's no condition or the condition is truthy
rc-web@42: 			if( !s.condition || s.condition() ) {
rc-web@42: 				if( s.async ) {
rc-web@42: 					scriptsAsync.push( s.src );
rc-web@42: 				}
rc-web@42: 				else {
rc-web@42: 					scripts.push( s.src );
rc-web@42: 				}
rc-web@42: 
rc-web@42: 				// Extension may contain callback functions
rc-web@42: 				if( typeof s.callback === 'function' ) {
rc-web@42: 					head.ready( s.src.match( /([\w\d_-]*)\.?[^\\\/]*$/i )[0], s.callback );
rc-web@42: 				}
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// Called once synchronous scritps finish loading
rc-web@42: 		function proceed() {
rc-web@42: 			// Load asynchronous scripts
rc-web@42: 			head.js.apply( null, scriptsAsync );
rc-web@42: 			
rc-web@42: 			start();
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		if( scripts.length ) {
rc-web@42: 			head.ready( proceed );
rc-web@42: 
rc-web@42: 			// Load synchronous scripts
rc-web@42: 			head.js.apply( null, scripts );
rc-web@42: 		}
rc-web@42: 		else {
rc-web@42: 			proceed();
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Starts up reveal.js by binding input events and navigating 
rc-web@42: 	 * to the current URL deeplink if there is one.
rc-web@42: 	 */
rc-web@42: 	function start() {
rc-web@42: 		// Subscribe to input
rc-web@42: 		addEventListeners();
rc-web@42: 
rc-web@42: 		// Updates the presentation to match the current configuration values
rc-web@42: 		configure();
rc-web@42: 
rc-web@42: 		// Read the initial hash
rc-web@42: 		readURL();
rc-web@42: 
rc-web@42: 		// Start auto-sliding if it's enabled
rc-web@42: 		cueAutoSlide();
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Applies the configuration settings from the config object.
rc-web@42: 	 */
rc-web@42: 	function configure() {
rc-web@42: 		if( supports3DTransforms === false ) {
rc-web@42: 			config.transition = 'linear';
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		if( config.controls && dom.controls ) {
rc-web@42: 			dom.controls.style.display = 'block';
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		if( config.progress && dom.progress ) {
rc-web@42: 			dom.progress.style.display = 'block';
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// Load the theme in the config, if it's not already loaded
rc-web@42: 		if( config.theme && dom.theme ) {
rc-web@42: 			var themeURL = dom.theme.getAttribute( 'href' );
rc-web@42: 			var themeFinder = /[^/]*?(?=\.css)/;
rc-web@42: 			var themeName = themeURL.match(themeFinder)[0];
rc-web@42: 			if(  config.theme !== themeName ) {
rc-web@42: 				themeURL = themeURL.replace(themeFinder, config.theme);
rc-web@42: 				dom.theme.setAttribute( 'href', themeURL );
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 
rc-web@42: 
rc-web@42: 		if( config.transition !== 'default' ) {
rc-web@42: 			dom.wrapper.classList.add( config.transition );
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		if( config.mouseWheel ) {
rc-web@42: 			document.addEventListener( 'DOMMouseScroll', onDocumentMouseScroll, false ); // FF
rc-web@42: 			document.addEventListener( 'mousewheel', onDocumentMouseScroll, false );
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		if( config.rollingLinks ) {
rc-web@42: 			// Add some 3D magic to our anchors
rc-web@42: 			linkify();
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	function addEventListeners() {
rc-web@42: 		document.addEventListener( 'touchstart', onDocumentTouchStart, false );
rc-web@42: 		document.addEventListener( 'touchmove', onDocumentTouchMove, false );
rc-web@42: 		document.addEventListener( 'touchend', onDocumentTouchEnd, false );
rc-web@42: 		window.addEventListener( 'hashchange', onWindowHashChange, false );
rc-web@42: 
rc-web@42: 		if( config.keyboard ) {
rc-web@42: 			document.addEventListener( 'keydown', onDocumentKeyDown, false );
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		if ( config.controls && dom.controls ) {
rc-web@42: 			dom.controlsLeft.addEventListener( 'click', preventAndForward( navigateLeft ), false );
rc-web@42: 			dom.controlsRight.addEventListener( 'click', preventAndForward( navigateRight ), false );
rc-web@42: 			dom.controlsUp.addEventListener( 'click', preventAndForward( navigateUp ), false );
rc-web@42: 			dom.controlsDown.addEventListener( 'click', preventAndForward( navigateDown ), false );	
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	function removeEventListeners() {
rc-web@42: 		document.removeEventListener( 'keydown', onDocumentKeyDown, false );
rc-web@42: 		document.removeEventListener( 'touchstart', onDocumentTouchStart, false );
rc-web@42: 		document.removeEventListener( 'touchmove', onDocumentTouchMove, false );
rc-web@42: 		document.removeEventListener( 'touchend', onDocumentTouchEnd, false );
rc-web@42: 		window.removeEventListener( 'hashchange', onWindowHashChange, false );
rc-web@42: 		
rc-web@42: 		if ( config.controls && dom.controls ) {
rc-web@42: 			dom.controlsLeft.removeEventListener( 'click', preventAndForward( navigateLeft ), false );
rc-web@42: 			dom.controlsRight.removeEventListener( 'click', preventAndForward( navigateRight ), false );
rc-web@42: 			dom.controlsUp.removeEventListener( 'click', preventAndForward( navigateUp ), false );
rc-web@42: 			dom.controlsDown.removeEventListener( 'click', preventAndForward( navigateDown ), false );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Extend object a with the properties of object b. 
rc-web@42: 	 * If there's a conflict, object b takes precedence.
rc-web@42: 	 */
rc-web@42: 	function extend( a, b ) {
rc-web@42: 		for( var i in b ) {
rc-web@42: 			a[ i ] = b[ i ];
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Measures the distance in pixels between point a
rc-web@42: 	 * and point b. 
rc-web@42: 	 * 
rc-web@42: 	 * @param {Object} a point with x/y properties
rc-web@42: 	 * @param {Object} b point with x/y properties
rc-web@42: 	 */
rc-web@42: 	function distanceBetween( a, b ) {
rc-web@42: 		var dx = a.x - b.x,
rc-web@42: 			dy = a.y - b.y;
rc-web@42: 
rc-web@42: 		return Math.sqrt( dx*dx + dy*dy );
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Prevents an events defaults behavior calls the 
rc-web@42: 	 * specified delegate.
rc-web@42: 	 * 
rc-web@42: 	 * @param {Function} delegate The method to call 
rc-web@42: 	 * after the wrapper has been executed
rc-web@42: 	 */
rc-web@42: 	function preventAndForward( delegate ) {
rc-web@42: 		return function( event ) {
rc-web@42: 			event.preventDefault();
rc-web@42: 			delegate.call();
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Causes the address bar to hide on mobile devices, 
rc-web@42: 	 * more vertical space ftw.
rc-web@42: 	 */
rc-web@42: 	function removeAddressBar() {
rc-web@42: 		setTimeout( function() {
rc-web@42: 			window.scrollTo( 0, 1 );
rc-web@42: 		}, 0 );
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Handler for the document level 'keydown' event.
rc-web@42: 	 * 
rc-web@42: 	 * @param {Object} event
rc-web@42: 	 */
rc-web@42: 	function onDocumentKeyDown( event ) {
rc-web@42: 		// FFT: Use document.querySelector( ':focus' ) === null 
rc-web@42: 		// instead of checking contentEditable?
rc-web@42: 
rc-web@42: 		// Disregard the event if the target is editable or a 
rc-web@42: 		// modifier is present
rc-web@42: 		if ( event.target.contentEditable != 'inherit' || event.shiftKey || event.altKey || event.ctrlKey || event.metaKey ) return;
rc-web@42: 				
rc-web@42: 		var triggered = false;
rc-web@42: 
rc-web@42: 		switch( event.keyCode ) {
rc-web@42: 			// p, page up
rc-web@42: 			case 80: case 33: navigatePrev(); triggered = true; break; 
rc-web@42: 			// n, page down
rc-web@42: 			case 78: case 34: navigateNext(); triggered = true; break;
rc-web@42: 			// h, left
rc-web@42: 			case 72: case 37: navigateLeft(); triggered = true; break;
rc-web@42: 			// l, right
rc-web@42: 			case 76: case 39: navigateRight(); triggered = true; break;
rc-web@42: 			// k, up
rc-web@42: 			case 75: case 38: navigateUp(); triggered = true; break;
rc-web@42: 			// j, down
rc-web@42: 			case 74: case 40: navigateDown(); triggered = true; break;
rc-web@42: 			// home
rc-web@42: 			case 36: navigateTo( 0 ); triggered = true; break;
rc-web@42: 			// end
rc-web@42: 			case 35: navigateTo( Number.MAX_VALUE ); triggered = true; break;
rc-web@42: 			// space
rc-web@42: 			case 32: overviewIsActive() ? deactivateOverview() : navigateNext(); triggered = true; break;
rc-web@42: 			// return
rc-web@42: 			case 13: if( overviewIsActive() ) { deactivateOverview(); triggered = true; } break;
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// If the input resulted in a triggered action we should prevent 
rc-web@42: 		// the browsers default behavior
rc-web@42: 		if( triggered ) {
rc-web@42: 			event.preventDefault();
rc-web@42: 		}
rc-web@42: 		else if ( event.keyCode === 27 && supports3DTransforms ) {
rc-web@42: 			toggleOverview();
rc-web@42: 	
rc-web@42: 			event.preventDefault();
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// If auto-sliding is enabled we need to cue up 
rc-web@42: 		// another timeout
rc-web@42: 		cueAutoSlide();
rc-web@42: 
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Handler for the document level 'touchstart' event,
rc-web@42: 	 * enables support for swipe and pinch gestures.
rc-web@42: 	 */
rc-web@42: 	function onDocumentTouchStart( event ) {
rc-web@42: 		touch.startX = event.touches[0].clientX;
rc-web@42: 		touch.startY = event.touches[0].clientY;
rc-web@42: 		touch.startCount = event.touches.length;
rc-web@42: 
rc-web@42: 		// If there's two touches we need to memorize the distance 
rc-web@42: 		// between those two points to detect pinching
rc-web@42: 		if( event.touches.length === 2 ) {
rc-web@42: 			touch.startSpan = distanceBetween( {
rc-web@42: 				x: event.touches[1].clientX,
rc-web@42: 				y: event.touches[1].clientY
rc-web@42: 			}, {
rc-web@42: 				x: touch.startX,
rc-web@42: 				y: touch.startY
rc-web@42: 			} );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Handler for the document level 'touchmove' event.
rc-web@42: 	 */
rc-web@42: 	function onDocumentTouchMove( event ) {
rc-web@42: 		// Each touch should only trigger one action
rc-web@42: 		if( !touch.handled ) {
rc-web@42: 			var currentX = event.touches[0].clientX;
rc-web@42: 			var currentY = event.touches[0].clientY;
rc-web@42: 
rc-web@42: 			// If the touch started off with two points and still has 
rc-web@42: 			// two active touches; test for the pinch gesture
rc-web@42: 			if( event.touches.length === 2 && touch.startCount === 2 ) {
rc-web@42: 
rc-web@42: 				// The current distance in pixels between the two touch points
rc-web@42: 				var currentSpan = distanceBetween( {
rc-web@42: 					x: event.touches[1].clientX,
rc-web@42: 					y: event.touches[1].clientY
rc-web@42: 				}, {
rc-web@42: 					x: touch.startX,
rc-web@42: 					y: touch.startY
rc-web@42: 				} );
rc-web@42: 
rc-web@42: 				// If the span is larger than the desire amount we've got 
rc-web@42: 				// ourselves a pinch
rc-web@42: 				if( Math.abs( touch.startSpan - currentSpan ) > touch.threshold ) {
rc-web@42: 					touch.handled = true;
rc-web@42: 
rc-web@42: 					if( currentSpan < touch.startSpan ) {
rc-web@42: 						activateOverview();
rc-web@42: 					}
rc-web@42: 					else {
rc-web@42: 						deactivateOverview();
rc-web@42: 					}
rc-web@42: 				}
rc-web@42: 
rc-web@42: 			}
rc-web@42: 			// There was only one touch point, look for a swipe
rc-web@42: 			else if( event.touches.length === 1 ) {
rc-web@42: 				var deltaX = currentX - touch.startX,
rc-web@42: 					deltaY = currentY - touch.startY;
rc-web@42: 
rc-web@42: 				if( deltaX > touch.threshold && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
rc-web@42: 					touch.handled = true;
rc-web@42: 					navigateLeft();
rc-web@42: 				} 
rc-web@42: 				else if( deltaX < -touch.threshold && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
rc-web@42: 					touch.handled = true;
rc-web@42: 					navigateRight();
rc-web@42: 				} 
rc-web@42: 				else if( deltaY > touch.threshold ) {
rc-web@42: 					touch.handled = true;
rc-web@42: 					navigateUp();
rc-web@42: 				} 
rc-web@42: 				else if( deltaY < -touch.threshold ) {
rc-web@42: 					touch.handled = true;
rc-web@42: 					navigateDown();
rc-web@42: 				}
rc-web@42: 			}
rc-web@42: 
rc-web@42: 			event.preventDefault();
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Handler for the document level 'touchend' event.
rc-web@42: 	 */
rc-web@42: 	function onDocumentTouchEnd( event ) {
rc-web@42: 		touch.handled = false;
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Handles mouse wheel scrolling, throttled to avoid 
rc-web@42: 	 * skipping multiple slides.
rc-web@42: 	 */
rc-web@42: 	function onDocumentMouseScroll( event ){
rc-web@42: 		clearTimeout( mouseWheelTimeout );
rc-web@42: 
rc-web@42: 		mouseWheelTimeout = setTimeout( function() {
rc-web@42: 			var delta = event.detail || -event.wheelDelta;
rc-web@42: 			if( delta > 0 ) {
rc-web@42: 				navigateNext();
rc-web@42: 			}
rc-web@42: 			else {
rc-web@42: 				navigatePrev();
rc-web@42: 			}
rc-web@42: 		}, 100 );
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Handler for the window level 'hashchange' event.
rc-web@42: 	 * 
rc-web@42: 	 * @param {Object} event
rc-web@42: 	 */
rc-web@42: 	function onWindowHashChange( event ) {
rc-web@42: 		readURL();
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Wrap all links in 3D goodness.
rc-web@42: 	 */
rc-web@42: 	function linkify() {
rc-web@42: 		if( supports3DTransforms && !( 'msPerspective' in document.body.style ) ) {
rc-web@42:         	var nodes = document.querySelectorAll( '.reveal .slides section a:not(.image)' );
rc-web@42: 
rc-web@42: 	        for( var i = 0, len = nodes.length; i < len; i++ ) {
rc-web@42: 	            var node = nodes[i];
rc-web@42: 	            
rc-web@42: 	            if( node.textContent && !node.querySelector( 'img' ) && ( !node.className || !node.classList.contains( node, 'roll' ) ) ) {
rc-web@42: 	                node.classList.add( 'roll' );
rc-web@42: 	                node.innerHTML = '<span data-title="'+ node.text +'">' + node.innerHTML + '</span>';
rc-web@42: 	            }
rc-web@42: 	        };
rc-web@42:         }
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Displays the overview of slides (quick nav) by 
rc-web@42: 	 * scaling down and arranging all slide elements.
rc-web@42: 	 * 
rc-web@42: 	 * Experimental feature, might be dropped if perf 
rc-web@42: 	 * can't be improved.
rc-web@42: 	 */
rc-web@42: 	function activateOverview() {
rc-web@42: 		
rc-web@42: 		dom.wrapper.classList.add( 'overview' );
rc-web@42: 
rc-web@42: 		var horizontalSlides = Array.prototype.slice.call( document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
rc-web@42: 
rc-web@42: 		for( var i = 0, len1 = horizontalSlides.length; i < len1; i++ ) {
rc-web@42: 			var hslide = horizontalSlides[i],
rc-web@42: 				htransform = 'translateZ(-2500px) translate(' + ( ( i - indexh ) * 105 ) + '%, 0%)';
rc-web@42: 			
rc-web@42: 			hslide.setAttribute( 'data-index-h', i );
rc-web@42: 			hslide.style.display = 'block';
rc-web@42: 			hslide.style.WebkitTransform = htransform;
rc-web@42: 			hslide.style.MozTransform = htransform;
rc-web@42: 			hslide.style.msTransform = htransform;
rc-web@42: 			hslide.style.OTransform = htransform;
rc-web@42: 			hslide.style.transform = htransform;
rc-web@42: 		
rc-web@42: 			if( !hslide.classList.contains( 'stack' ) ) {
rc-web@42: 				// Navigate to this slide on click
rc-web@42: 				hslide.addEventListener( 'click', onOverviewSlideClicked, true );
rc-web@42: 			}
rc-web@42: 	
rc-web@42: 			var verticalSlides = Array.prototype.slice.call( hslide.querySelectorAll( 'section' ) );
rc-web@42: 
rc-web@42: 			for( var j = 0, len2 = verticalSlides.length; j < len2; j++ ) {
rc-web@42: 				var vslide = verticalSlides[j],
rc-web@42: 					vtransform = 'translate(0%, ' + ( ( j - ( i === indexh ? indexv : 0 ) ) * 105 ) + '%)';
rc-web@42: 
rc-web@42: 				vslide.setAttribute( 'data-index-h', i );
rc-web@42: 				vslide.setAttribute( 'data-index-v', j );
rc-web@42: 				vslide.style.display = 'block';
rc-web@42: 				vslide.style.WebkitTransform = vtransform;
rc-web@42: 				vslide.style.MozTransform = vtransform;
rc-web@42: 				vslide.style.msTransform = vtransform;
rc-web@42: 				vslide.style.OTransform = vtransform;
rc-web@42: 				vslide.style.transform = vtransform;
rc-web@42: 
rc-web@42: 				// Navigate to this slide on click
rc-web@42: 				vslide.addEventListener( 'click', onOverviewSlideClicked, true );
rc-web@42: 			}
rc-web@42: 			
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Exits the slide overview and enters the currently
rc-web@42: 	 * active slide.
rc-web@42: 	 */
rc-web@42: 	function deactivateOverview() {
rc-web@42: 		dom.wrapper.classList.remove( 'overview' );
rc-web@42: 
rc-web@42: 		var slides = Array.prototype.slice.call( document.querySelectorAll( '.reveal .slides section' ) );
rc-web@42: 
rc-web@42: 		for( var i = 0, len = slides.length; i < len; i++ ) {
rc-web@42: 			var element = slides[i];
rc-web@42: 
rc-web@42: 			// Resets all transforms to use the external styles
rc-web@42: 			element.style.WebkitTransform = '';
rc-web@42: 			element.style.MozTransform = '';
rc-web@42: 			element.style.msTransform = '';
rc-web@42: 			element.style.OTransform = '';
rc-web@42: 			element.style.transform = '';
rc-web@42: 
rc-web@42: 			element.removeEventListener( 'click', onOverviewSlideClicked );
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		slide();
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Checks if the overview is currently active.
rc-web@42: 	 * 
rc-web@42: 	 * @return {Boolean} true if the overview is active,
rc-web@42: 	 * false otherwise
rc-web@42: 	 */
rc-web@42: 	function overviewIsActive() {
rc-web@42: 		return dom.wrapper.classList.contains( 'overview' );
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Invoked when a slide is and we're in the overview.
rc-web@42: 	 */
rc-web@42: 	function onOverviewSlideClicked( event ) {
rc-web@42: 		// TODO There's a bug here where the event listeners are not 
rc-web@42: 		// removed after deactivating the overview.
rc-web@42: 		if( overviewIsActive() ) {
rc-web@42: 			event.preventDefault();
rc-web@42: 
rc-web@42: 			deactivateOverview();
rc-web@42: 
rc-web@42: 			indexh = this.getAttribute( 'data-index-h' );
rc-web@42: 			indexv = this.getAttribute( 'data-index-v' );
rc-web@42: 
rc-web@42: 			slide();
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Updates one dimension of slides by showing the slide
rc-web@42: 	 * with the specified index.
rc-web@42: 	 * 
rc-web@42: 	 * @param {String} selector A CSS selector that will fetch
rc-web@42: 	 * the group of slides we are working with
rc-web@42: 	 * @param {Number} index The index of the slide that should be
rc-web@42: 	 * shown
rc-web@42: 	 * 
rc-web@42: 	 * @return {Number} The index of the slide that is now shown,
rc-web@42: 	 * might differ from the passed in index if it was out of 
rc-web@42: 	 * bounds.
rc-web@42: 	 */
rc-web@42: 	function updateSlides( selector, index ) {
rc-web@42: 		
rc-web@42: 		// Select all slides and convert the NodeList result to
rc-web@42: 		// an array
rc-web@42: 		var slides = Array.prototype.slice.call( document.querySelectorAll( selector ) ),
rc-web@42: 			slidesLength = slides.length;
rc-web@42: 		
rc-web@42: 		if( slidesLength ) {
rc-web@42: 
rc-web@42: 			// Should the index loop?
rc-web@42: 			if( config.loop ) {
rc-web@42: 				index %= slidesLength;
rc-web@42: 
rc-web@42: 				if( index < 0 ) {
rc-web@42: 					index = slidesLength + index;
rc-web@42: 				}
rc-web@42: 			}
rc-web@42: 			
rc-web@42: 			// Enforce max and minimum index bounds
rc-web@42: 			index = Math.max( Math.min( index, slidesLength - 1 ), 0 );
rc-web@42: 			
rc-web@42: 			for( var i = 0; i < slidesLength; i++ ) {
rc-web@42: 				var slide = slides[i];
rc-web@42: 
rc-web@42: 				// Optimization; hide all slides that are three or more steps 
rc-web@42: 				// away from the present slide
rc-web@42: 				if( overviewIsActive() === false ) {
rc-web@42: 					// The distance loops so that it measures 1 between the first
rc-web@42: 					// and last slides
rc-web@42: 					var distance = Math.abs( ( index - i ) % ( slidesLength - 3 ) ) || 0;
rc-web@42: 
rc-web@42: 					slide.style.display = distance > 3 ? 'none' : 'block';
rc-web@42: 				}
rc-web@42: 
rc-web@42: 				slides[i].classList.remove( 'past' );
rc-web@42: 				slides[i].classList.remove( 'present' );
rc-web@42: 				slides[i].classList.remove( 'future' );
rc-web@42: 
rc-web@42: 				if( i < index ) {
rc-web@42: 					// Any element previous to index is given the 'past' class
rc-web@42: 					slides[i].classList.add( 'past' );
rc-web@42: 				}
rc-web@42: 				else if( i > index ) {
rc-web@42: 					// Any element subsequent to index is given the 'future' class
rc-web@42: 					slides[i].classList.add( 'future' );
rc-web@42: 				}
rc-web@42: 
rc-web@42: 				// If this element contains vertical slides
rc-web@42: 				if( slide.querySelector( 'section' ) ) {
rc-web@42: 					slides[i].classList.add( 'stack' );
rc-web@42: 				}
rc-web@42: 			}
rc-web@42: 
rc-web@42: 			// Mark the current slide as present
rc-web@42: 			slides[index].classList.add( 'present' );
rc-web@42: 
rc-web@42: 			// If this slide has a state associated with it, add it
rc-web@42: 			// onto the current state of the deck
rc-web@42: 			var slideState = slides[index].getAttribute( 'data-state' );
rc-web@42: 			if( slideState ) {
rc-web@42: 				state = state.concat( slideState.split( ' ' ) );
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 		else {
rc-web@42: 			// Since there are no slides we can't be anywhere beyond the 
rc-web@42: 			// zeroth index
rc-web@42: 			index = 0;
rc-web@42: 		}
rc-web@42: 		
rc-web@42: 		return index;
rc-web@42: 		
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Updates the visual slides to represent the currently
rc-web@42: 	 * set indices. 
rc-web@42: 	 */
rc-web@42: 	function slide( h, v ) {
rc-web@42: 		// Remember where we were at before
rc-web@42: 		previousSlide = currentSlide;
rc-web@42: 
rc-web@42: 		// Remember the state before this slide
rc-web@42: 		var stateBefore = state.concat();
rc-web@42: 
rc-web@42: 		// Reset the state array
rc-web@42: 		state.length = 0;
rc-web@42: 
rc-web@42: 		var indexhBefore = indexh,
rc-web@42: 			indexvBefore = indexv;
rc-web@42: 
rc-web@42: 		// Activate and transition to the new slide
rc-web@42: 		indexh = updateSlides( HORIZONTAL_SLIDES_SELECTOR, h === undefined ? indexh : h );
rc-web@42: 		indexv = updateSlides( VERTICAL_SLIDES_SELECTOR, v === undefined ? indexv : v );
rc-web@42: 
rc-web@42: 		// Apply the new state
rc-web@42: 		stateLoop: for( var i = 0, len = state.length; i < len; i++ ) {
rc-web@42: 			// Check if this state existed on the previous slide. If it 
rc-web@42: 			// did, we will avoid adding it repeatedly.
rc-web@42: 			for( var j = 0; j < stateBefore.length; j++ ) {
rc-web@42: 				if( stateBefore[j] === state[i] ) {
rc-web@42: 					stateBefore.splice( j, 1 );
rc-web@42: 					continue stateLoop;
rc-web@42: 				}
rc-web@42: 			}
rc-web@42: 
rc-web@42: 			document.documentElement.classList.add( state[i] );
rc-web@42: 
rc-web@42: 			// Dispatch custom event matching the state's name
rc-web@42: 			dispatchEvent( state[i] );
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// Clean up the remaints of the previous state
rc-web@42: 		while( stateBefore.length ) {
rc-web@42: 			document.documentElement.classList.remove( stateBefore.pop() );
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// Update progress if enabled
rc-web@42: 		if( config.progress && dom.progress ) {
rc-web@42: 			dom.progressbar.style.width = ( indexh / ( document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ).length - 1 ) ) * window.innerWidth + 'px';
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// Close the overview if it's active
rc-web@42: 		if( overviewIsActive() ) {
rc-web@42: 			activateOverview();
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		updateControls();
rc-web@42: 		
rc-web@42: 		clearTimeout( writeURLTimeout );
rc-web@42: 		writeURLTimeout = setTimeout( writeURL, 1500 );
rc-web@42: 
rc-web@42: 		// Query all horizontal slides in the deck
rc-web@42: 		var horizontalSlides = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR );
rc-web@42: 
rc-web@42: 		// Find the current horizontal slide and any possible vertical slides
rc-web@42: 		// within it
rc-web@42: 		var currentHorizontalSlide = horizontalSlides[ indexh ],
rc-web@42: 			currentVerticalSlides = currentHorizontalSlide.querySelectorAll( 'section' );
rc-web@42: 
rc-web@42: 		// Store references to the previous and current slides
rc-web@42: 		currentSlide = currentVerticalSlides[ indexv ] || currentHorizontalSlide;
rc-web@42: 
rc-web@42: 		// Dispatch an event if the slide changed
rc-web@42: 		if( indexh !== indexhBefore || indexv !== indexvBefore ) {
rc-web@42: 			dispatchEvent( 'slidechanged', {
rc-web@42: 				'indexh': indexh, 
rc-web@42: 				'indexv': indexv,
rc-web@42: 				'previousSlide': previousSlide,
rc-web@42: 				'currentSlide': currentSlide
rc-web@42: 			} );
rc-web@42: 		}
rc-web@42: 		else {
rc-web@42: 			// Ensure that the previous slide is never the same as the current
rc-web@42: 			previousSlide = null;
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// Solves an edge case where the previous slide maintains the 
rc-web@42: 		// 'present' class when navigating between adjacent vertical 
rc-web@42: 		// stacks
rc-web@42: 		if( previousSlide ) {
rc-web@42: 			previousSlide.classList.remove( 'present' );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Updates the state and link pointers of the controls.
rc-web@42: 	 */
rc-web@42: 	function updateControls() {
rc-web@42: 		if ( !config.controls || !dom.controls ) {
rc-web@42: 			return;
rc-web@42: 		}
rc-web@42: 		
rc-web@42: 		var routes = availableRoutes();
rc-web@42: 
rc-web@42: 		// Remove the 'enabled' class from all directions
rc-web@42: 		[ dom.controlsLeft, dom.controlsRight, dom.controlsUp, dom.controlsDown ].forEach( function( node ) {
rc-web@42: 			node.classList.remove( 'enabled' );
rc-web@42: 		} )
rc-web@42: 
rc-web@42: 		if( routes.left ) dom.controlsLeft.classList.add( 'enabled' );
rc-web@42: 		if( routes.right ) dom.controlsRight.classList.add( 'enabled' );
rc-web@42: 		if( routes.up ) dom.controlsUp.classList.add( 'enabled' );
rc-web@42: 		if( routes.down ) dom.controlsDown.classList.add( 'enabled' );
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Determine what available routes there are for navigation.
rc-web@42: 	 * 
rc-web@42: 	 * @return {Object} containing four booleans: left/right/up/down
rc-web@42: 	 */
rc-web@42: 	function availableRoutes() {
rc-web@42: 		var horizontalSlides = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR );
rc-web@42: 		var verticalSlides = document.querySelectorAll( VERTICAL_SLIDES_SELECTOR );
rc-web@42: 
rc-web@42: 		return {
rc-web@42: 			left: indexh > 0,
rc-web@42: 			right: indexh < horizontalSlides.length - 1,
rc-web@42: 			up: indexv > 0,
rc-web@42: 			down: indexv < verticalSlides.length - 1
rc-web@42: 		};
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Reads the current URL (hash) and navigates accordingly.
rc-web@42: 	 */
rc-web@42: 	function readURL() {
rc-web@42: 		var hash = window.location.hash;
rc-web@42: 
rc-web@42: 		// Attempt to parse the hash as either an index or name
rc-web@42: 		var bits = hash.slice( 2 ).split( '/' ),
rc-web@42: 			name = hash.replace( /#|\//gi, '' );
rc-web@42: 
rc-web@42: 		// If the first bit is invalid and there is a name we can 
rc-web@42: 		// assume that this is a named link
rc-web@42: 		if( isNaN( parseInt( bits[0] ) ) && name.length ) {
rc-web@42: 			// Find the slide with the specified name
rc-web@42: 			var slide = document.querySelector( '#' + name );
rc-web@42: 
rc-web@42: 			if( slide ) {
rc-web@42: 				// Find the position of the named slide and navigate to it
rc-web@42: 				var indices = Reveal.getIndices( slide );
rc-web@42: 				navigateTo( indices.h, indices.v );
rc-web@42: 			}
rc-web@42: 			// If the slide doesn't exist, navigate to the current slide
rc-web@42: 			else {
rc-web@42: 				navigateTo( indexh, indexv );
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 		else {
rc-web@42: 			// Read the index components of the hash
rc-web@42: 			var h = parseInt( bits[0] ) || 0,
rc-web@42: 				v = parseInt( bits[1] ) || 0;
rc-web@42: 
rc-web@42: 			navigateTo( h, v );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Updates the page URL (hash) to reflect the current
rc-web@42: 	 * state. 
rc-web@42: 	 */
rc-web@42: 	function writeURL() {
rc-web@42: 		if( config.history ) {
rc-web@42: 			var url = '/';
rc-web@42: 			
rc-web@42: 			// Only include the minimum possible number of components in
rc-web@42: 			// the URL
rc-web@42: 			if( indexh > 0 || indexv > 0 ) url += indexh;
rc-web@42: 			if( indexv > 0 ) url += '/' + indexv;
rc-web@42: 			
rc-web@42: 			window.location.hash = url;
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Dispatches an event of the specified type from the 
rc-web@42: 	 * reveal DOM element.
rc-web@42: 	 */
rc-web@42: 	function dispatchEvent( type, properties ) {
rc-web@42: 		var event = document.createEvent( "HTMLEvents", 1, 2 );
rc-web@42: 		event.initEvent( type, true, true );
rc-web@42: 		extend( event, properties );
rc-web@42: 		dom.wrapper.dispatchEvent( event );
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Navigate to the next slide fragment.
rc-web@42: 	 * 
rc-web@42: 	 * @return {Boolean} true if there was a next fragment,
rc-web@42: 	 * false otherwise
rc-web@42: 	 */
rc-web@42: 	function nextFragment() {
rc-web@42: 		// Vertical slides:
rc-web@42: 		if( document.querySelector( VERTICAL_SLIDES_SELECTOR + '.present' ) ) {
rc-web@42: 			var verticalFragments = document.querySelectorAll( VERTICAL_SLIDES_SELECTOR + '.present .fragment:not(.visible)' );
rc-web@42: 			if( verticalFragments.length ) {
rc-web@42: 				verticalFragments[0].classList.add( 'visible' );
rc-web@42: 
rc-web@42: 				// Notify subscribers of the change
rc-web@42: 				dispatchEvent( 'fragmentshown', { fragment: verticalFragments[0] } );
rc-web@42: 				return true;
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 		// Horizontal slides:
rc-web@42: 		else {
rc-web@42: 			var horizontalFragments = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.present .fragment:not(.visible)' );
rc-web@42: 			if( horizontalFragments.length ) {
rc-web@42: 				horizontalFragments[0].classList.add( 'visible' );
rc-web@42: 
rc-web@42: 				// Notify subscribers of the change
rc-web@42: 				dispatchEvent( 'fragmentshown', { fragment: horizontalFragments[0] } );
rc-web@42: 				return true;
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		return false;
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Navigate to the previous slide fragment.
rc-web@42: 	 * 
rc-web@42: 	 * @return {Boolean} true if there was a previous fragment,
rc-web@42: 	 * false otherwise
rc-web@42: 	 */
rc-web@42: 	function previousFragment() {
rc-web@42: 		// Vertical slides:
rc-web@42: 		if( document.querySelector( VERTICAL_SLIDES_SELECTOR + '.present' ) ) {
rc-web@42: 			var verticalFragments = document.querySelectorAll( VERTICAL_SLIDES_SELECTOR + '.present .fragment.visible' );
rc-web@42: 			if( verticalFragments.length ) {
rc-web@42: 				verticalFragments[ verticalFragments.length - 1 ].classList.remove( 'visible' );
rc-web@42: 
rc-web@42: 				// Notify subscribers of the change
rc-web@42: 				dispatchEvent( 'fragmenthidden', { fragment: verticalFragments[ verticalFragments.length - 1 ] } );
rc-web@42: 				return true;
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 		// Horizontal slides:
rc-web@42: 		else {
rc-web@42: 			var horizontalFragments = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.present .fragment.visible' );
rc-web@42: 			if( horizontalFragments.length ) {
rc-web@42: 				horizontalFragments[ horizontalFragments.length - 1 ].classList.remove( 'visible' );
rc-web@42: 
rc-web@42: 				// Notify subscribers of the change
rc-web@42: 				dispatchEvent( 'fragmenthidden', { fragment: horizontalFragments[ horizontalFragments.length - 1 ] } );
rc-web@42: 				return true;
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 		
rc-web@42: 		return false;
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	function cueAutoSlide() {
rc-web@42: 		clearTimeout( autoSlideTimeout );
rc-web@42: 
rc-web@42: 		// Cue the next auto-slide if enabled
rc-web@42: 		if( config.autoSlide ) {
rc-web@42: 			autoSlideTimeout = setTimeout( navigateNext, config.autoSlide );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	/**
rc-web@42: 	 * Triggers a navigation to the specified indices.
rc-web@42: 	 * 
rc-web@42: 	 * @param {Number} h The horizontal index of the slide to show
rc-web@42: 	 * @param {Number} v The vertical index of the slide to show
rc-web@42: 	 */
rc-web@42: 	function navigateTo( h, v ) {
rc-web@42: 		slide( h, v );
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	function navigateLeft() {
rc-web@42: 		// Prioritize hiding fragments
rc-web@42: 		if( overviewIsActive() || previousFragment() === false ) {
rc-web@42: 			slide( indexh - 1, 0 );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 	function navigateRight() {
rc-web@42: 		// Prioritize revealing fragments
rc-web@42: 		if( overviewIsActive() || nextFragment() === false ) {
rc-web@42: 			slide( indexh + 1, 0 );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 	function navigateUp() {
rc-web@42: 		// Prioritize hiding fragments
rc-web@42: 		if( overviewIsActive() || previousFragment() === false ) {
rc-web@42: 			slide( indexh, indexv - 1 );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 	function navigateDown() {
rc-web@42: 		// Prioritize revealing fragments
rc-web@42: 		if( overviewIsActive() || nextFragment() === false ) {
rc-web@42: 			slide( indexh, indexv + 1 );
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Navigates backwards, prioritized in the following order:
rc-web@42: 	 * 1) Previous fragment
rc-web@42: 	 * 2) Previous vertical slide
rc-web@42: 	 * 3) Previous horizontal slide
rc-web@42: 	 */
rc-web@42: 	function navigatePrev() {
rc-web@42: 		// Prioritize revealing fragments
rc-web@42: 		if( previousFragment() === false ) {
rc-web@42: 			if( availableRoutes().up ) {
rc-web@42: 				navigateUp();
rc-web@42: 			}
rc-web@42: 			else {
rc-web@42: 				// Fetch the previous horizontal slide, if there is one
rc-web@42: 				var previousSlide = document.querySelector( '.reveal .slides>section.past:nth-child(' + indexh + ')' );
rc-web@42: 
rc-web@42: 				if( previousSlide ) {
rc-web@42: 					indexv = ( previousSlide.querySelectorAll('section').length + 1 ) || 0;
rc-web@42: 					indexh --;
rc-web@42: 					slide();
rc-web@42: 				}
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Same as #navigatePrev() but navigates forwards.
rc-web@42: 	 */
rc-web@42: 	function navigateNext() {
rc-web@42: 		// Prioritize revealing fragments
rc-web@42: 		if( nextFragment() === false ) {
rc-web@42: 			availableRoutes().down ? navigateDown() : navigateRight();
rc-web@42: 		}
rc-web@42: 
rc-web@42: 		// If auto-sliding is enabled we need to cue up 
rc-web@42: 		// another timeout
rc-web@42: 		cueAutoSlide();
rc-web@42: 	}
rc-web@42: 
rc-web@42: 	/**
rc-web@42: 	 * Toggles the slide overview mode on and off.
rc-web@42: 	 */
rc-web@42: 	function toggleOverview() {
rc-web@42: 		if( overviewIsActive() ) {
rc-web@42: 			deactivateOverview();
rc-web@42: 		}
rc-web@42: 		else {
rc-web@42: 			activateOverview();
rc-web@42: 		}
rc-web@42: 	}
rc-web@42: 	
rc-web@42: 	// Expose some methods publicly
rc-web@42: 	return {
rc-web@42: 		initialize: initialize,
rc-web@42: 		navigateTo: navigateTo,
rc-web@42: 		navigateLeft: navigateLeft,
rc-web@42: 		navigateRight: navigateRight,
rc-web@42: 		navigateUp: navigateUp,
rc-web@42: 		navigateDown: navigateDown,
rc-web@42: 		navigatePrev: navigatePrev,
rc-web@42: 		navigateNext: navigateNext,
rc-web@42: 		toggleOverview: toggleOverview,
rc-web@42: 
rc-web@42: 		// Adds or removes all internal event listeners (such as keyboard)
rc-web@42: 		addEventListeners: addEventListeners,
rc-web@42: 		removeEventListeners: removeEventListeners,
rc-web@42: 
rc-web@42: 		// Returns the indices of the current, or specified, slide
rc-web@42: 		getIndices: function( slide ) {
rc-web@42: 			// By default, return the current indices
rc-web@42: 			var h = indexh,
rc-web@42: 				v = indexv;
rc-web@42: 
rc-web@42: 			// If a slide is specified, return the indices of that slide
rc-web@42: 			if( slide ) {
rc-web@42: 				var isVertical = !!slide.parentNode.nodeName.match( /section/gi );
rc-web@42: 				var slideh = isVertical ? slide.parentNode : slide;
rc-web@42: 
rc-web@42: 				// Select all horizontal slides
rc-web@42: 				var horizontalSlides = Array.prototype.slice.call( document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
rc-web@42: 
rc-web@42: 				// Now that we know which the horizontal slide is, get its index
rc-web@42: 				h = Math.max( horizontalSlides.indexOf( slideh ), 0 );
rc-web@42: 
rc-web@42: 				// If this is a vertical slide, grab the vertical index
rc-web@42: 				if( isVertical ) {
rc-web@42: 					v = Math.max( Array.prototype.slice.call( slide.parentNode.children ).indexOf( slide ), 0 );
rc-web@42: 				}
rc-web@42: 			}
rc-web@42: 
rc-web@42: 			return { h: h, v: v };
rc-web@42: 		},
rc-web@42: 
rc-web@42: 		// Returns the previous slide element, may be null
rc-web@42: 		getPreviousSlide: function() {
rc-web@42: 			return previousSlide
rc-web@42: 		},
rc-web@42: 
rc-web@42: 		// Returns the current slide element
rc-web@42: 		getCurrentSlide: function() {
rc-web@42: 			return currentSlide
rc-web@42: 		},
rc-web@42: 
rc-web@42: 		// Helper method, retrieves query string as a key/value hash
rc-web@42: 		getQueryHash: function() {
rc-web@42: 			var query = {};
rc-web@42: 
rc-web@42: 			location.search.replace( /[A-Z0-9]+?=(\w*)/gi, function(a) {
rc-web@42: 				query[ a.split( '=' ).shift() ] = a.split( '=' ).pop();
rc-web@42: 			} );
rc-web@42: 
rc-web@42: 			return query;
rc-web@42: 		},
rc-web@42: 
rc-web@42: 		// Forward event binding to the reveal DOM element
rc-web@42: 		addEventListener: function( type, listener, useCapture ) {
rc-web@42: 			if( 'addEventListener' in window ) {
rc-web@42: 				( dom.wrapper || document.querySelector( '.reveal' ) ).addEventListener( type, listener, useCapture );
rc-web@42: 			}
rc-web@42: 		},
rc-web@42: 		removeEventListener: function( type, listener, useCapture ) {
rc-web@42: 			if( 'addEventListener' in window ) {
rc-web@42: 				( dom.wrapper || document.querySelector( '.reveal' ) ).removeEventListener( type, listener, useCapture );
rc-web@42: 			}
rc-web@42: 		}
rc-web@42: 	};
rc-web@42: 	
rc-web@42: })();