fa20-bt/js/reveal.js

3714 lines
98 KiB
JavaScript

/*!
* reveal.js
* http://lab.hakim.se/reveal-js
* MIT licensed
*
* Copyright (C) 2014 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-of-type',
// 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,
// 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,
// 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,
// 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,
// 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
focusBodyOnPageVisiblityChange: true,
// Theme (see /css/theme)
theme: null,
// Transition style
transition: 'default', // none/fade/slide/convex/concave/zoom
// Transition speed
transitionSpeed: 'default', // default/fast/slow
// Transition style for full page slide backgrounds
backgroundTransition: 'default', // 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"
// 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,
// 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,
// Cached references to DOM elements
dom = {},
// Features supported by the browser, see #checkCapabilities()
features = {},
// Client is a mobile device, see #checkCapabilities()
isMobileDevice,
// 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
};
/**
* Starts up the presentation if the client is capable.
*/
function initialize( options ) {
checkCapabilities();
if( !features.transforms2d && !features.transforms3d ) {
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 );
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() {
features.transforms3d = '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;
features.transforms2d = '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;
features.requestAnimationFrameMethod = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame;
features.requestAnimationFrame = typeof features.requestAnimationFrameMethod === 'function';
features.canvas = !!document.createElement( 'canvas' ).getContext;
isMobileDevice = navigator.userAgent.match( /(iphone|ipod|android)/gi );
}
/**
* 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();
// 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 );
}
/**
* 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' );
// 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',
'<div class="navigate-left"></div>' +
'<div class="navigate-right"></div>' +
'<div class="navigate-up"></div>' +
'<div class="navigate-down"></div>' );
// Slide number
dom.slideNumber = createSingletonNode( dom.wrapper, 'div', 'slide-number', '' );
// State background element [DEPRECATED]
createSingletonNode( dom.wrapper, 'div', 'state-background', null );
// 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' );
// 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' ) );
}
/**
* 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 ) {
var node = container.querySelector( '.' + classname );
if( !node ) {
node = document.createElement( tagname );
node.classList.add( classname );
if( innerHTML !== null ) {
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() {
if( isPrintingPDF() ) {
document.body.classList.add( 'print-pdf' );
}
// Clear prior backgrounds
dom.background.innerHTML = '';
dom.background.classList.add( 'no-transition' );
// Iterate over all horizontal slides
toArray( document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).forEach( function( slideh ) {
var backgroundStack;
if( isPrintingPDF() ) {
backgroundStack = createBackground( slideh, slideh );
}
else {
backgroundStack = createBackground( slideh, dom.background );
}
// Iterate over all vertical slides
toArray( slideh.querySelectorAll( 'section' ) ).forEach( function( slidev ) {
if( isPrintingPDF() ) {
createBackground( slidev, slidev );
}
else {
createBackground( slidev, backgroundStack );
}
} );
} );
// 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' ),
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 ) ) {
element.style.backgroundImage = 'url('+ 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 ) {
element.setAttribute( 'data-background-hash', data.background +
data.backgroundSize +
data.backgroundImage +
data.backgroundVideo +
data.backgroundColor +
data.backgroundRepeat +
data.backgroundPosition +
data.backgroundTransition );
}
// Additional and optional background properties
if( data.backgroundSize ) element.style.backgroundSize = data.backgroundSize;
if( data.backgroundImage ) element.style.backgroundImage = 'url("' + data.backgroundImage + '")';
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 );
// Create video background element
if( data.backgroundVideo ) {
var video = document.createElement( 'video' );
// Support comma separated lists of video sources
data.backgroundVideo.split( ',' ).forEach( function( source ) {
video.innerHTML += '<source src="'+ source +'">';
} );
element.appendChild( video );
}
container.appendChild( element );
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( 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 = document.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';
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' );
}
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' );
} );
}
// 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 );
}
}
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 );
}
if( config.progress && dom.progress ) {
dom.progress.addEventListener( 'click', onProgressClicked, false );
}
if( config.focusBodyOnPageVisiblityChange ) {
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 );
}
}
[ 'touchstart', 'click' ].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 );
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.OTransform = transform;
element.style.transform = transform;
}
/**
* 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( child.style.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 = document.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 = document.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 openPreview( url ) {
closePreview();
dom.preview = document.createElement( 'div' );
dom.preview.classList.add( 'preview-link-overlay' );
dom.wrapper.appendChild( dom.preview );
dom.preview.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.preview.querySelector( 'iframe' ).addEventListener( 'load', function( event ) {
dom.preview.classList.add( 'loaded' );
}, false );
dom.preview.querySelector( '.close' ).addEventListener( 'click', function( event ) {
closePreview();
event.preventDefault();
}, false );
dom.preview.querySelector( '.external' ).addEventListener( 'click', function( event ) {
closePreview();
}, false );
setTimeout( function() {
dom.preview.classList.add( 'visible' );
}, 1 );
}
/**
* Closes the iframe preview window.
*/
function closePreview() {
if( dom.preview ) {
dom.preview.setAttribute( 'src', '' );
dom.preview.parentNode.removeChild( dom.preview );
dom.preview = null;
}
}
/**
* Applies JavaScript-controlled layout rules to the
* presentation.
*/
function layout() {
if( dom.wrapper && !isPrintingPDF() ) {
// Available space to scale within
var availableWidth = dom.wrapper.offsetWidth,
availableHeight = dom.wrapper.offsetHeight;
// Reduce available space by margin
availableWidth -= ( availableHeight * config.margin );
availableHeight -= ( availableHeight * config.margin );
// Dimensions of the content
var slideWidth = config.width,
slideHeight = config.height,
slidePadding = 20; // TODO Dig this out of DOM
// Layout the contents of the slides
layoutSlideContents( config.width, config.height, slidePadding );
// Slide width may be a percentage of available width
if( typeof slideWidth === 'string' && /%$/.test( slideWidth ) ) {
slideWidth = parseInt( slideWidth, 10 ) / 100 * availableWidth;
}
// Slide height may be a percentage of available height
if( typeof slideHeight === 'string' && /%$/.test( slideHeight ) ) {
slideHeight = parseInt( slideHeight, 10 ) / 100 * availableHeight;
}
dom.slides.style.width = slideWidth + 'px';
dom.slides.style.height = slideHeight + 'px';
// Determine scale of content to fit within available space
scale = Math.min( availableWidth / slideWidth, availableHeight / slideHeight );
// Respect max/min scale settings
scale = Math.max( scale, config.minScale );
scale = Math.min( scale, config.maxScale );
// Prefer zooming in WebKit so that content remains crisp
if( /webkit/i.test( navigator.userAgent ) && typeof dom.slides.style.zoom !== 'undefined' ) {
dom.slides.style.zoom = scale;
}
// Apply scale transform as a fallback
else {
dom.slides.style.left = '50%';
dom.slides.style.top = '50%';
dom.slides.style.bottom = 'auto';
dom.slides.style.right = 'auto';
transformElement( dom.slides, 'translate(-50%, -50%) scale('+ scale +')' );
}
// Select all slides, vertical and horizontal
var slides = toArray( document.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( ( ( slideHeight - 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';
}
} );
}
/**
* 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.
*
* Experimental feature, might be dropped if perf
* can't be improved.
*/
function activateOverview() {
// Only proceed if enabled in config
if( config.overview ) {
// Don't auto-slide while in overview mode
cancelAutoSlide();
var wasActive = dom.wrapper.classList.contains( 'overview' );
// Vary the depth of the overview based on screen size
var depth = window.innerWidth < 400 ? 1000 : 2500;
dom.wrapper.classList.add( 'overview' );
dom.wrapper.classList.remove( 'overview-deactivating' );
var horizontalSlides = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR );
for( var i = 0, len1 = horizontalSlides.length; i < len1; i++ ) {
var hslide = horizontalSlides[i],
hoffset = config.rtl ? -105 : 105;
hslide.setAttribute( 'data-index-h', i );
// Apply CSS transform
transformElement( hslide, 'translateZ(-'+ depth +'px) translate(' + ( ( i - indexh ) * hoffset ) + '%, 0%)' );
if( hslide.classList.contains( 'stack' ) ) {
var verticalSlides = hslide.querySelectorAll( 'section' );
for( var j = 0, len2 = verticalSlides.length; j < len2; j++ ) {
var verticalIndex = i === indexh ? indexv : getPreviousVerticalIndex( hslide );
var vslide = verticalSlides[j];
vslide.setAttribute( 'data-index-h', i );
vslide.setAttribute( 'data-index-v', j );
// Apply CSS transform
transformElement( vslide, 'translate(0%, ' + ( ( j - verticalIndex ) * 105 ) + '%)' );
// Navigate to this slide on click
vslide.addEventListener( 'click', onOverviewSlideClicked, true );
}
}
else {
// Navigate to this slide on click
hslide.addEventListener( 'click', onOverviewSlideClicked, true );
}
}
updateSlidesVisibility();
layout();
if( !wasActive ) {
// Notify observers of the overview showing
dispatchEvent( 'overviewshown', {
'indexh': indexh,
'indexv': indexv,
'currentSlide': currentSlide
} );
}
}
}
/**
* Exits the slide overview and enters the currently
* active slide.
*/
function deactivateOverview() {
// Only proceed if enabled in config
if( config.overview ) {
dom.wrapper.classList.remove( 'overview' );
// 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 );
// Select all slides
toArray( document.querySelectorAll( SLIDES_SELECTOR ) ).forEach( function( slide ) {
// Resets all transforms to use the external styles
transformElement( slide, '' );
slide.removeEventListener( 'click', onOverviewSlideClicked, true );
} );
slide( indexh, indexv );
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 dom.wrapper.classList.contains( '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.body;
// 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() {
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 = document.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 ) {
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() );
}
// If the overview is active, re-activate it to update positions
if( isOverview() ) {
activateOverview();
}
// 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' );
// Reset all slides upon navigate to home
// Issue: #285
if ( document.querySelector( HOME_SLIDE_SELECTOR ).classList.contains( 'present' ) ) {
// Launch async task
setTimeout( function () {
var slides = toArray( document.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 ) {
stopEmbeddedContent( previousSlide );
startEmbeddedContent( currentSlide );
}
updateControls();
updateProgress();
updateBackground();
updateParallax();
updateSlideNumber();
// 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();
sortAllFragments();
updateControls();
updateProgress();
updateBackground( true );
updateSlideNumber();
}
/**
* Resets all vertical slides so that only the first
* is visible.
*/
function resetVerticalSlides() {
var horizontalSlides = toArray( document.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' );
}
} );
} );
}
/**
* Sorts and formats all of fragments in the
* presentation.
*/
function sortAllFragments() {
var horizontalSlides = toArray( document.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' ) );
} );
}
/**
* 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( document.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', '' );
// 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' );
// 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( document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ),
horizontalSlidesLength = horizontalSlides.length,
distanceX,
distanceY;
if( horizontalSlidesLength ) {
// 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 : 1;
}
// Limit view distance on weaker devices
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;
// Loops so that it measures 1 between the first and last slides
distanceX = Math.abs( ( indexh - x ) % ( horizontalSlidesLength - viewDistance ) ) || 0;
// Show the horizontal slide if it's within the view distance
if( distanceX < viewDistance ) {
horizontalSlide.style.display = 'block';
loadSlide( horizontalSlide );
}
else {
horizontalSlide.style.display = 'none';
}
if( verticalSlidesLength ) {
var oy = getPreviousVerticalIndex( horizontalSlide );
for( var y = 0; y < verticalSlidesLength; y++ ) {
var verticalSlide = verticalSlides[y];
distanceY = x === indexh ? Math.abs( indexv - y ) : Math.abs( y - oy );
if( distanceX + distanceY < viewDistance ) {
verticalSlide.style.display = 'block';
loadSlide( verticalSlide );
}
else {
verticalSlide.style.display = 'none';
}
}
}
}
}
}
/**
* Updates the progress bar to reflect the current slide.
*/
function updateProgress() {
// Update progress if enabled
if( config.progress && dom.progress ) {
dom.progressbar.style.width = getProgress() * window.innerWidth + 'px';
}
}
/**
* Updates the slide number div to reflect the current slide.
*/
function updateSlideNumber() {
// Update slide number if enabled
if( config.slideNumber && dom.slideNumber) {
// Display the number of the page using 'indexh - indexv' format
var indexString = indexh;
if( indexv > 0 ) {
indexString += ' - ' + indexv;
}
dom.slideNumber.innerHTML = indexString;
}
}
/**
* 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 ) currentVideo.play();
// 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;
}
// 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 = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ),
verticalSlides = document.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;
var horizontalSlideCount = horizontalSlides.length;
var horizontalOffset = -( backgroundWidth - slideWidth ) / ( horizontalSlideCount-1 ) * indexh;
var slideHeight = dom.background.offsetHeight;
var verticalSlideCount = verticalSlides.length;
var verticalOffset = verticalSlideCount > 1 ? -( backgroundHeight - slideHeight ) / ( verticalSlideCount-1 ) * indexv : 0;
dom.background.style.backgroundPosition = horizontalOffset + 'px ' + verticalOffset + 'px';
}
}
/**
* Loads any content that is set to load lazily (data-src)
* inside of the given slide.
*/
function loadSlide( slide ) {
// Media elements with data-src attributes
toArray( slide.querySelectorAll( 'img[data-src], video[data-src], audio[data-src], iframe[data-src]' ) ).forEach( function( element ) {
element.setAttribute( 'src', element.getAttribute( 'data-src' ) );
element.removeAttribute( 'data-src' );
} );
// Media elements with multiple <source>s
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();
}
} );
}
/**
* 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 ),
verticalSlides = document.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 };
}
}
/**
* Start playback of any embedded content inside of
* the targeted slide.
*/
function startEmbeddedContent( slide ) {
if( slide && !isSpeakerNotes() ) {
// HTML5 media elements
toArray( slide.querySelectorAll( 'video, audio' ) ).forEach( function( el ) {
if( el.hasAttribute( 'data-autoplay' ) ) {
el.play();
}
} );
// iframe embeds
toArray( slide.querySelectorAll( 'iframe' ) ).forEach( function( el ) {
el.contentWindow.postMessage( 'slide:start', '*' );
});
// YouTube embeds
toArray( slide.querySelectorAll( 'iframe[src*="youtube.com/embed/"]' ) ).forEach( function( el ) {
if( el.hasAttribute( 'data-autoplay' ) ) {
el.contentWindow.postMessage( '{"event":"command","func":"playVideo","args":""}', '*' );
}
});
}
}
/**
* Stop playback of any embedded content inside of
* the targeted slide.
*/
function stopEmbeddedContent( slide ) {
if( slide ) {
// HTML5 media elements
toArray( slide.querySelectorAll( 'video, audio' ) ).forEach( function( el ) {
if( !el.hasAttribute( 'data-ignore' ) ) {
el.pause();
}
} );
// iframe embeds
toArray( slide.querySelectorAll( 'iframe' ) ).forEach( function( el ) {
el.contentWindow.postMessage( 'slide:stop', '*' );
});
// YouTube embeds
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":""}', '*' );
}
});
}
}
/**
* Returns a value ranging from 0-1 that represents
* how far into the presentation we have navigated.
*/
function getProgress() {
var horizontalSlides = toArray( document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
// The number of past and total slides
var totalCount = document.querySelectorAll( SLIDES_SELECTOR + ':not(.stack)' ).length;
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++;
}
}
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;
try {
// Find the slide with the specified name
element = document.querySelector( '#' + name );
}
catch( e ) {
// If the ID is an invalid selector a harmless SyntaxError
// may be thrown here.
}
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 {
var url = '/';
// Attempt to create a named link based on the slide's ID
var id = currentSlide.getAttribute( 'id' );
if( id ) {
id = id.toLowerCase();
id = id.replace( /[^a-zA-Z0-9\-\_\:\.]/g, '' );
}
// If the current slide has an ID, use that as a named link
if( currentSlide && 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( 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( toArray( slide.parentNode.querySelectorAll( 'section' ) ).indexOf( slide ), 0 );
}
}
if( !slide && currentSlide ) {
var hasFragments = currentSlide.querySelectorAll( '.fragment' ).length > 0;
if( hasFragments ) {
var visibleFragments = currentSlide.querySelectorAll( '.fragment.visible' );
f = visibleFragments.length - 1;
}
}
return { h: h, v: v, f: f };
}
/**
* Retrieves the total number of slides in this presentation.
*/
function getTotalSlides() {
return document.querySelectorAll( SLIDES_SELECTOR + ':not(.stack)' ).length;
}
/**
* 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' );
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
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() || config.loop === true ) ) {
autoSlideTimeout = setTimeout( navigateNext, 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 = document.querySelector( HORIZONTAL_SLIDES_SELECTOR + '.past:nth-child(' + indexh + ')' );
if( previousSlide ) {
var v = ( previousSlide.querySelectorAll( 'section' ).length - 1 ) || undefined;
var h = indexh - 1;
slide( h, v );
}
}
}
}
/**
* 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();
}
// --------------------------------------------------------------------//
// ----------------------------- EVENTS -------------------------------//
// --------------------------------------------------------------------//
/**
* Called by all event handlers that are based on user
* input.
*/
function onUserInput( event ) {
if( config.autoSlideStoppable ) {
pauseAutoSlide();
}
}
/**
* 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 activeElement = document.activeElement;
var hasFocus = !!( document.activeElement && ( document.activeElement.type || document.activeElement.href || document.activeElement.contentEditable !== 'inherit' ) );
// Disregard the event if there's a focused element or a
// keyboard modifier key is present
if( hasFocus || (event.shiftKey && event.keyCode !== 32) || event.altKey || event.ctrlKey || event.metaKey ) return;
// While paused only allow "unpausing" keyboard events (b and .)
if( isPaused() && [66,190,191].indexOf( event.keyCode ) === -1 ) {
return false;
}
var triggered = false;
// 1. User defined key bindings
if( typeof config.keyboard === 'object' ) {
for( var 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();
}
// ESC or O key
else if ( ( event.keyCode === 27 || event.keyCode === 79 ) && features.transforms3d ) {
if( dom.preview ) {
closePreview();
}
else {
toggleOverview();
}
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 ) {
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 ) {
// 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( navigator.userAgent.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( document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).length;
var slideIndex = Math.floor( ( event.clientX / dom.wrapper.offsetWidth ) * slidesTotal );
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 ) {
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 ) {
var url = event.target.getAttribute( 'href' );
if( url ) {
openPreview( 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 = 50;
this.thickness = 3;
// 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.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.diameter / 2 ) - this.thickness,
x = this.diameter / 2,
y = this.diameter / 2,
iconSize = 14;
// 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 + 2, 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 - 2, iconSize );
this.context.fillRect( iconSize / 2 + 2, 0, iconSize / 2 - 2, iconSize );
}
else {
this.context.beginPath();
this.context.translate( 2, 0 );
this.context.moveTo( 0, 0 );
this.context.lineTo( iconSize - 2, 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 --------------------------------//
// --------------------------------------------------------------------//
return {
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,
// 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 at the specified index, y is optional
getSlide: function( x, y ) {
var horizontalSlide = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR )[ x ];
var verticalSlides = horizontalSlide && horizontalSlide.querySelectorAll( 'section' );
if( typeof y !== 'undefined' ) {
return verticalSlides ? verticalSlides[ y ] : undefined;
}
return horizontalSlide;
},
// 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 document.querySelector( SLIDES_SELECTOR + '.past' ) == null ? true : false;
},
// 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 } );
}
};
})();