reveal.js

/*!
 * reveal.js
 * http://lab.hakim.se/reveal-js
 * MIT licensed
 *
 * Copyright (C) 2013 Hakim El Hattab, http://hakim.se
 */
var Reveal = (function(){

	'use strict';

	var SLIDES_SELECTOR = '.reveal .slides section',
		HORIZONTAL_SLIDES_SELECTOR = '.reveal .slides>section',
		VERTICAL_SLIDES_SELECTOR = '.reveal .slides>section.present>section',
		HOME_SLIDE_SELECTOR = '.reveal .slides>section:first-child',

		// Configurations 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: 1.0,

			// 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,

			// Enable the slide overview mode
			overview: true,

			// Vertical centring 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,

			// Turns fragments on and off globally
			fragments: true,

			// 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,

			// Enable slide navigation via mouse wheel
			mouseWheel: false,

			// Apply a 3D roll to links on hover
			rollingLinks: true,

			// Opens links in an iframe preview overlay
			previewLinks: false,

			// Theme (see /css/theme)
			theme: null,

			// Transition style
			transition: 'default', // default/cube/page/concave/zoom/linear/fade/none

			// Transition speed
			transitionSpeed: 'default', // default/fast/slow

			// Transition style for full page slide backgrounds
			backgroundTransition: 'default', // default/linear

			// Script dependencies to load
			dependencies: []
		},

		// The current auto-slide duration
		autoSlide = 0,

		// The horizontal and vertical 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 = [],

		// The current scale of the presentation (see width/height config)
		scale = 1,

		// 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,

		// Detect support for CSS 2D transforms
		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,

		// A delay used to activate the overview mode
		activateOverviewTimeout = 0,

		// A delay used to deactivate the overview mode
		deactivateOverviewTimeout = 0,

		// Flags if the interaction event listeners are bound
		eventsAreBound = false,

		// Holds information about the currently ongoing touch input
		touch = {
			startX: 0,
			startY: 0,
			startSpan: 0,
			startCount: 0,
			handled: false,
			threshold: 80
		};

	/**
	 * 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;
		}

		// Force a layout when the whole page, incl fonts, has loaded
		window.addEventListener( 'load', layout, false );

		// Copy options over to our config object
		extend( config, options );

		// Hide the address bar in mobile browsers
		hideAddressBar();

		// Loads the dependencies and continues to #start() once done
		load();

	}

	/**
	 * 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() {

		// Cache references to key DOM elements
		dom.theme = document.querySelector( '#theme' );
		dom.wrapper = document.querySelector( '.reveal' );
		dom.slides = document.querySelector( '.reveal .slides' );

		// Background element
		if( !document.querySelector( '.reveal .backgrounds' ) ) {
			dom.background = document.createElement( 'div' );
			dom.background.classList.add( 'backgrounds' );
			dom.wrapper.appendChild( dom.background );
		}