comparison www/p/js/reveal.js @ 42:49c94f63b8b0

css for nexus 7 and associated files- archive m.a added - remove later

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