fa20-bt/js/reveal.js
2012-11-10 19:14:16 -05:00

1559 lines
44 KiB
JavaScript

/*!
* reveal.js 2.2 r45
* http://lab.hakim.se/reveal-js
* MIT licensed
*
* Copyright (C) 2011-2012 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',
// Configurations defaults, can be overridden at initialization time
config = {
// Display controls in the bottom right corner
controls: true,
// Display a presentation progress bar
progress: true,
// Push each slide change to the browser history
history: false,
// Enable keyboard shortcuts for navigation
keyboard: true,
// Enable the slide overview mode
overview: true,
// Vertical centering of slides
center: true,
// Loop the presentation
loop: 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,
// Enable slide navigation via mouse wheel
mouseWheel: true,
// Apply a 3D roll to links on hover
rollingLinks: true,
// Transition style (see /css/theme)
theme: null,
// Transition style
transition: 'default', // default/cube/page/concave/zoom/linear/none
// Script dependencies to load
dependencies: []
},
// Stores if the next slide should be shown automatically
// after n milliseconds
autoSlide = config.autoSlide,
// The horizontal and verical index of the currently active slide
indexh = 0,
indexv = 0,
// The previous and current slide HTML elements
previousSlide,
currentSlide,
// Slides may hold a data-state attribute which we pick up and apply
// as a class to the body. This list contains the combined state of
// all current slides.
state = [],
// Cached references to DOM elements
dom = {},
// Detect support for CSS 3D transforms
supports3DTransforms = 'WebkitPerspective' in document.body.style ||
'MozPerspective' in document.body.style ||
'msPerspective' in document.body.style ||
'OPerspective' in document.body.style ||
'perspective' in document.body.style,
supports2DTransforms = 'WebkitTransform' in document.body.style ||
'MozTransform' in document.body.style ||
'msTransform' in document.body.style ||
'OTransform' in document.body.style ||
'transform' in document.body.style,
// Throttles mouse wheel navigation
mouseWheelTimeout = 0,
// An interval used to automatically move on to the next slide
autoSlideTimeout = 0,
// Delays updates to the URL due to a Chrome thumbnailer bug
writeURLTimeout = 0,
// Holds information about the currently ongoing touch input
touch = {
startX: 0,
startY: 0,
startSpan: 0,
startCount: 0,
handled: false,
threshold: 80
};
/**
* Starts up the presentation if the client is capable.
*/
function initialize( options ) {
if( ( !supports2DTransforms && !supports3DTransforms ) ) {
document.body.setAttribute( 'class', 'no-transforms' );
// If the browser doesn't support core features we won't be
// using JavaScript to control the presentation
return;
}
// Copy options over to our config object
extend( config, options );
// Hide the address bar in mobile browsers
hideAddressBar();
// Loads the dependencies and continues to #start() once done
load();
}
/**
* Finds and stores references to DOM elements which are
* required by the presentation. If a required element is
* not found, it is created.
*/
function setupDOM() {
// Cache references to key DOM elements
dom.theme = document.querySelector( '#theme' );
dom.wrapper = document.querySelector( '.reveal' );
// Progress bar
if( !dom.wrapper.querySelector( '.progress' ) && config.progress ) {
var progressElement = document.createElement( 'div' );
progressElement.classList.add( 'progress' );
progressElement.innerHTML = '<span></span>';
dom.wrapper.appendChild( progressElement );
}
// Arrow controls
if( !dom.wrapper.querySelector( '.controls' ) && config.controls ) {
var controlsElement = document.createElement( 'aside' );
controlsElement.classList.add( 'controls' );
controlsElement.innerHTML = '<div class="navigate-left"></div>' +
'<div class="navigate-right"></div>' +
'<div class="navigate-up"></div>' +
'<div class="navigate-down"></div>';
dom.wrapper.appendChild( controlsElement );
}
// Presentation background element
if( !dom.wrapper.querySelector( '.state-background' ) ) {
var backgroundElement = document.createElement( 'div' );
backgroundElement.classList.add( 'state-background' );
dom.wrapper.appendChild( backgroundElement );
}
// Overlay graphic which is displayed during the paused mode
if( !dom.wrapper.querySelector( '.pause-overlay' ) ) {
var pausedElement = document.createElement( 'div' );
pausedElement.classList.add( 'pause-overlay' );
dom.wrapper.appendChild( pausedElement );
}
// Cache references to elements
dom.progress = document.querySelector( '.reveal .progress' );
dom.progressbar = document.querySelector( '.reveal .progress span' );
if ( config.controls ) {
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' ) );
}
}
/**
* Hides the address bar if we're on a mobile device.
*/
function hideAddressBar() {
if( navigator.userAgent.match( /(iphone|ipod|android)/i ) ) {
// Give the page some scrollable overflow
document.documentElement.style.overflow = 'scroll';
document.body.style.height = '120%';
// Events that should trigger the address bar to hide
window.addEventListener( 'load', removeAddressBar, false );
window.addEventListener( 'orientationchange', removeAddressBar, false );
}
}
/**
* Loads the dependencies of reveal.js. Dependencies are
* defined via the configuration option 'dependencies'
* and will be loaded prior to starting/binding reveal.js.
* Some dependencies may have an 'async' flag, if so they
* will load after reveal.js has been started up.
*/
function load() {
var scripts = [],
scriptsAsync = [];
for( var i = 0, len = config.dependencies.length; i < len; i++ ) {
var s = config.dependencies[i];
// Load if there's no condition or the condition is truthy
if( !s.condition || s.condition() ) {
if( s.async ) {
scriptsAsync.push( s.src );
}
else {
scripts.push( s.src );
}
// Extension may contain callback functions
if( typeof s.callback === 'function' ) {
head.ready( s.src.match( /([\w\d_\-]*)\.?js|[^\\\/]*$/i )[0], s.callback );
}
}
}
// Called once synchronous scritps finish loading
function proceed() {
if( scriptsAsync.length ) {
// Load asynchronous scripts
head.js.apply( null, scriptsAsync );
}
start();
}
if( scripts.length ) {
head.ready( proceed );
// Load synchronous scripts
head.js.apply( null, scripts );
}
else {
proceed();
}
}
/**
* Starts up reveal.js by binding input events and navigating
* to the current URL deeplink if there is one.
*/
function start() {
// Make sure we've got all the DOM elements we need
setupDOM();
// Subscribe to input
addEventListeners();
// Updates the presentation to match the current configuration values
configure();
// Force an initial layout, will thereafter be invoked as the window
// is resized
layout();
// Read the initial hash
readURL();
// Start auto-sliding if it's enabled
cueAutoSlide();
// Notify listeners that the presentation is ready but use a 1ms
// timeout to ensure it's not fired synchronously after #initialize()
setTimeout( function() {
dispatchEvent( 'ready', {
'indexh': indexh,
'indexv': indexv,
'currentSlide': currentSlide
} );
}, 1 );
}
/**
* Applies the configuration settings from the config object.
*/
function configure() {
if( supports3DTransforms === false ) {
config.transition = 'linear';
}
if( config.controls && dom.controls ) {
dom.controls.style.display = 'block';
}
if( config.progress && dom.progress ) {
dom.progress.style.display = 'block';
}
if( config.transition !== 'default' ) {
dom.wrapper.classList.add( config.transition );
}
if( config.center ) {
dom.wrapper.classList.add( 'center' );
}
if( config.mouseWheel ) {
document.addEventListener( 'DOMMouseScroll', onDocumentMouseScroll, false ); // FF
document.addEventListener( 'mousewheel', onDocumentMouseScroll, false );
}
// 3D links
if( config.rollingLinks ) {
linkify();
}
// 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 );
}
}
}
/**
* Binds all event listeners.
*/
function addEventListeners() {
document.addEventListener( 'touchstart', onDocumentTouchStart, false );
document.addEventListener( 'touchmove', onDocumentTouchMove, false );
document.addEventListener( 'touchend', onDocumentTouchEnd, false );
window.addEventListener( 'hashchange', onWindowHashChange, false );
window.addEventListener( 'resize', onWindowResize, false );
if( config.keyboard ) {
document.addEventListener( 'keydown', onDocumentKeyDown, false );
}
if ( config.progress && dom.progress ) {
dom.progress.addEventListener( 'click', preventAndForward( onProgressClick ), false );
}
if ( config.controls && dom.controls ) {
dom.controlsLeft.forEach( function( el ) { el.addEventListener( 'click', preventAndForward( navigateLeft ), false ); } );
dom.controlsRight.forEach( function( el ) { el.addEventListener( 'click', preventAndForward( navigateRight ), false ); } );
dom.controlsUp.forEach( function( el ) { el.addEventListener( 'click', preventAndForward( navigateUp ), false ); } );
dom.controlsDown.forEach( function( el ) { el.addEventListener( 'click', preventAndForward( navigateDown ), false ); } );
dom.controlsPrev.forEach( function( el ) { el.addEventListener( 'click', preventAndForward( navigatePrev ), false ); } );
dom.controlsNext.forEach( function( el ) { el.addEventListener( 'click', preventAndForward( navigateNext ), false ); } );
}
}
/**
* Unbinds all event listeners.
*/
function removeEventListeners() {
document.removeEventListener( 'keydown', onDocumentKeyDown, false );
document.removeEventListener( 'touchstart', onDocumentTouchStart, false );
document.removeEventListener( 'touchmove', onDocumentTouchMove, false );
document.removeEventListener( 'touchend', onDocumentTouchEnd, false );
window.removeEventListener( 'hashchange', onWindowHashChange, false );
window.removeEventListener( 'resize', onWindowResize, false );
if ( config.progress && dom.progress ) {
dom.progress.removeEventListener( 'click', preventAndForward( onProgressClick ), false );
}
if ( config.controls && dom.controls ) {
dom.controlsLeft.forEach( function( el ) { el.removeEventListener( 'click', preventAndForward( navigateLeft ), false ); } );
dom.controlsRight.forEach( function( el ) { el.removeEventListener( 'click', preventAndForward( navigateRight ), false ); } );
dom.controlsUp.forEach( function( el ) { el.removeEventListener( 'click', preventAndForward( navigateUp ), false ); } );
dom.controlsDown.forEach( function( el ) { el.removeEventListener( 'click', preventAndForward( navigateDown ), false ); } );
dom.controlsPrev.forEach( function( el ) { el.removeEventListener( 'click', preventAndForward( navigatePrev ), false ); } );
dom.controlsNext.forEach( function( el ) { el.removeEventListener( 'click', preventAndForward( navigateNext ), 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 );
}
function each( targets, method, args ) {
targets.forEach( function( el ) {
el[method].apply( el, args );
} );
}
/**
* Measures the distance in pixels between point a
* and point b.
*
* @param {Object} a point with x/y properties
* @param {Object} b point with x/y properties
*/
function distanceBetween( a, b ) {
var dx = a.x - b.x,
dy = a.y - b.y;
return Math.sqrt( dx*dx + dy*dy );
}
/**
* Prevents an events defaults behavior calls the
* specified delegate.
*
* @param {Function} delegate The method to call
* after the wrapper has been executed
*/
function preventAndForward( delegate ) {
return function( event ) {
event.preventDefault();
delegate.call( null, event );
};
}
/**
* Causes the address bar to hide on mobile devices,
* more vertical space ftw.
*/
function removeAddressBar() {
setTimeout( function() {
window.scrollTo( 0, 1 );
}, 0 );
}
/**
* Dispatches an event of the specified type from the
* reveal DOM element.
*/
function dispatchEvent( type, properties ) {
var event = document.createEvent( "HTMLEvents", 1, 2 );
event.initEvent( type, true, true );
extend( event, properties );
dom.wrapper.dispatchEvent( event );
}
/**
* Wrap all links in 3D goodness.
*/
function linkify() {
if( supports3DTransforms && !( 'msPerspective' in document.body.style ) ) {
var nodes = document.querySelectorAll( SLIDES_SELECTOR + ' a:not(.image)' );
for( var i = 0, len = nodes.length; i < len; i++ ) {
var node = nodes[i];
if( node.textContent && !node.querySelector( 'img' ) && ( !node.className || !node.classList.contains( node, 'roll' ) ) ) {
node.classList.add( 'roll' );
node.innerHTML = '<span data-title="'+ node.text +'">' + node.innerHTML + '</span>';
}
}
}
}
/**
* Applies JavaScript-controlled layout rules to the
* presentation.
*/
function layout() {
if( config.center ) {
// Select all slides, vertical and horizontal
var slides = toArray( document.querySelectorAll( SLIDES_SELECTOR ) );
// Determine the minimum top offset for slides
var minTop = -dom.wrapper.offsetHeight / 2;
for( var i = 0, len = slides.length; i < len; i++ ) {
var slide = slides[ i ];
// Don't bother update invisible slides
if( slide.style.display === 'none' ) {
continue;
}
// Vertical stacks are not centered since their section
// children will be
if( slide.classList.contains( 'stack' ) ) {
slide.style.top = 0;
}
else {
slide.style.top = Math.max( - ( slide.offsetHeight / 2 ) - 20, minTop ) + '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( stack ) {
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( stack && stack.classList.contains( 'stack' ) ) {
return parseInt( stack.getAttribute( 'data-previous-indexv' ) || 0 );
}
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 ) {
dom.wrapper.classList.add( 'overview' );
var horizontalSlides = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR );
for( var i = 0, len1 = horizontalSlides.length; i < len1; i++ ) {
var hslide = horizontalSlides[i],
htransform = 'translateZ(-2500px) translate(' + ( ( i - indexh ) * 105 ) + '%, 0%)';
hslide.setAttribute( 'data-index-h', i );
hslide.style.display = 'block';
hslide.style.WebkitTransform = htransform;
hslide.style.MozTransform = htransform;
hslide.style.msTransform = htransform;
hslide.style.OTransform = htransform;
hslide.style.transform = htransform;
if( hslide.classList.contains( 'stack' ) ) {
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],
vtransform = 'translate(0%, ' + ( ( j - verticalIndex ) * 105 ) + '%)';
vslide.setAttribute( 'data-index-h', i );
vslide.setAttribute( 'data-index-v', j );
vslide.style.display = 'block';
vslide.style.WebkitTransform = vtransform;
vslide.style.MozTransform = vtransform;
vslide.style.msTransform = vtransform;
vslide.style.OTransform = vtransform;
vslide.style.transform = vtransform;
// Navigate to this slide on click
vslide.addEventListener( 'click', onOverviewSlideClicked, true );
}
}
else {
// Navigate to this slide on click
hslide.addEventListener( 'click', onOverviewSlideClicked, true );
}
}
layout();
}
}
/**
* 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' );
// Select all slides
var slides = toArray( document.querySelectorAll( SLIDES_SELECTOR ) );
for( var i = 0, len = slides.length; i < len; i++ ) {
var element = slides[i];
// Resets all transforms to use the external styles
element.style.WebkitTransform = '';
element.style.MozTransform = '';
element.style.msTransform = '';
element.style.OTransform = '';
element.style.transform = '';
element.removeEventListener( 'click', onOverviewSlideClicked );
}
slide( indexh, indexv );
}
}
/**
* 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 {
isOverviewActive() ? deactivateOverview() : activateOverview();
}
}
/**
* Checks if the overview is currently active.
*
* @return {Boolean} true if the overview is active,
* false otherwise
*/
function isOverviewActive() {
return dom.wrapper.classList.contains( 'overview' );
}
/**
* 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.mozRequestFullScreen ||
element.msRequestFullScreen;
if( requestMethod ) {
requestMethod.apply( element );
}
}
/**
* Enters the paused mode which fades everything on screen to
* black.
*/
function pause() {
dom.wrapper.classList.add( 'paused' );
}
/**
* Exits from the paused mode.
*/
function resume() {
dom.wrapper.classList.remove( 'paused' );
}
/**
* Toggles the paused mode on and off.
*/
function togglePause() {
if( isPaused() ) {
resume();
}
else {
pause();
}
}
/**
* Checks if we are currently in the paused mode.
*/
function isPaused() {
return dom.wrapper.classList.contains( 'paused' );
}
/**
* 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
*/
function slide( h, v ) {
// 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.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,
indexvBefore = indexv;
// Activate and transition to the new slide
indexh = updateSlides( HORIZONTAL_SLIDES_SELECTOR, h === undefined ? indexh : h );
indexv = updateSlides( VERTICAL_SLIDES_SELECTOR, v === undefined ? indexv : v );
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 remaints 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( isOverviewActive() ) {
activateOverview();
}
// Update the URL hash after a delay since updating it mid-transition
// is likely to cause visual lag
clearTimeout( writeURLTimeout );
writeURLTimeout = setTimeout( writeURL, 1500 );
// Find the current horizontal slide and any possible vertical slides
// within it
var currentHorizontalSlide = horizontalSlides[ indexh ],
currentVerticalSlides = currentHorizontalSlide.querySelectorAll( 'section' );
// Store references to the previous and current slides
currentSlide = currentVerticalSlides[ indexv ] || currentHorizontalSlide;
// Dispatch an event if the slide changed
if( indexh !== indexhBefore || indexv !== indexvBefore ) {
dispatchEvent( 'slidechanged', {
'indexh': indexh,
'indexv': indexv,
'previousSlide': previousSlide,
'currentSlide': currentSlide
} );
}
else {
// Ensure that the previous slide is never the same as the current
previousSlide = null;
}
// Solves an edge case where the previous slide maintains the
// 'present' class when navigating between adjacent vertical
// stacks
if( previousSlide ) {
previousSlide.classList.remove( 'present' );
}
updateControls();
updateProgress();
}
/**
* 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;
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];
// Optimization; hide all slides that are three or more steps
// away from the present slide
if( isOverviewActive() === false ) {
// The distance loops so that it measures 1 between the first
// and last slides
var distance = Math.abs( ( index - i ) % ( slidesLength - 3 ) ) || 0;
element.style.display = distance > 3 ? 'none' : 'block';
}
slides[i].classList.remove( 'past' );
slides[i].classList.remove( 'present' );
slides[i].classList.remove( 'future' );
if( i < index ) {
// Any element previous to index is given the 'past' class
slides[i].classList.add( 'past' );
}
else if( i > index ) {
// Any element subsequent to index is given the 'future' class
slides[i].classList.add( 'future' );
}
// If this element contains vertical slides
if( element.querySelector( 'section' ) ) {
slides[i].classList.add( 'stack' );
}
}
// Mark the current slide as present
slides[index].classList.add( 'present' );
// If this slide has a state associated with it, add it
// onto the current state of the deck
var slideState = slides[index].getAttribute( 'data-state' );
if( slideState ) {
state = state.concat( slideState.split( ' ' ) );
}
// If this slide has a data-autoslide attribtue associated use this as
// autoSlide value otherwise use the global configured time
var slideAutoSlide = slides[index].getAttribute( 'data-autoslide' );
if( slideAutoSlide ) {
autoSlide = parseInt( slideAutoSlide );
} else {
autoSlide = config.autoSlide
}
}
else {
// Since there are no slides we can't be anywhere beyond the
// zeroth index
index = 0;
}
return index;
}
/**
* Updates the progress bar to reflect the current slide.
*/
function updateProgress() {
// Update progress if enabled
if( config.progress && dom.progress ) {
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++;
}
dom.progressbar.style.width = ( pastCount / ( totalCount - 1 ) ) * window.innerWidth + 'px';
}
}
/**
* Updates the state of all control/navigation arrows.
*/
function updateControls() {
if ( config.controls && dom.controls ) {
var routes = availableRoutes();
// 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' );
} );
// 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' ); } );
}
}
/**
* 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 );
return {
left: indexh > 0,
right: indexh < horizontalSlides.length - 1,
up: indexv > 0,
down: indexv < verticalSlides.length - 1
};
}
/**
* Reads the current URL (hash) and navigates accordingly.
*/
function readURL() {
var hash = window.location.hash;
// Attempt to parse the hash as either an index or name
var bits = hash.slice( 2 ).split( '/' ),
name = hash.replace( /#|\//gi, '' );
// If the first bit is invalid and there is a name we can
// assume that this is a named link
if( isNaN( parseInt( bits[0], 10 ) ) && name.length ) {
// Find the slide with the specified name
var element = document.querySelector( '#' + name );
if( element ) {
// Find the position of the named slide and navigate to it
var indices = Reveal.getIndices( element );
slide( indices.h, indices.v );
}
// If the slide doesn't exist, navigate to the current slide
else {
slide( indexh, indexv );
}
}
else {
// Read the index components of the hash
var h = parseInt( bits[0], 10 ) || 0,
v = parseInt( bits[1], 10 ) || 0;
slide( h, v );
}
}
/**
* Updates the page URL (hash) to reflect the current
* state.
*/
function writeURL() {
if( config.history ) {
var url = '/';
// If the current slide has an ID, use that as a named link
if( currentSlide && typeof currentSlide.getAttribute( 'id' ) === 'string' ) {
url = '/' + currentSlide.getAttribute( '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> }
*/
function getIndices( slide ) {
// By default, return the current indices
var h = indexh,
v = indexv;
// If a slide is specified, return the indices of that slide
if( slide ) {
var isVertical = !!slide.parentNode.nodeName.match( /section/gi );
var slideh = isVertical ? slide.parentNode : slide;
// Select all horizontal slides
var horizontalSlides = 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.children ).indexOf( slide ), 0 );
}
}
return { h: h, v: v };
}
/**
* Navigate to the next slide fragment.
*
* @return {Boolean} true if there was a next fragment,
* false otherwise
*/
function nextFragment() {
// Vertical slides:
if( document.querySelector( VERTICAL_SLIDES_SELECTOR + '.present' ) ) {
var verticalFragments = document.querySelectorAll( VERTICAL_SLIDES_SELECTOR + '.present .fragment:not(.visible)' );
if( verticalFragments.length ) {
verticalFragments[0].classList.add( 'visible' );
// Notify subscribers of the change
dispatchEvent( 'fragmentshown', { fragment: verticalFragments[0] } );
return true;
}
}
// Horizontal slides:
else {
var horizontalFragments = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.present .fragment:not(.visible)' );
if( horizontalFragments.length ) {
horizontalFragments[0].classList.add( 'visible' );
// Notify subscribers of the change
dispatchEvent( 'fragmentshown', { fragment: horizontalFragments[0] } );
return true;
}
}
return false;
}
/**
* Navigate to the previous slide fragment.
*
* @return {Boolean} true if there was a previous fragment,
* false otherwise
*/
function previousFragment() {
// Vertical slides:
if( document.querySelector( VERTICAL_SLIDES_SELECTOR + '.present' ) ) {
var verticalFragments = document.querySelectorAll( VERTICAL_SLIDES_SELECTOR + '.present .fragment.visible' );
if( verticalFragments.length ) {
verticalFragments[ verticalFragments.length - 1 ].classList.remove( 'visible' );
// Notify subscribers of the change
dispatchEvent( 'fragmenthidden', { fragment: verticalFragments[ verticalFragments.length - 1 ] } );
return true;
}
}
// Horizontal slides:
else {
var horizontalFragments = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.present .fragment.visible' );
if( horizontalFragments.length ) {
horizontalFragments[ horizontalFragments.length - 1 ].classList.remove( 'visible' );
// Notify subscribers of the change
dispatchEvent( 'fragmenthidden', { fragment: horizontalFragments[ horizontalFragments.length - 1 ] } );
return true;
}
}
return false;
}
/**
* Cues a new automated slide if enabled in the config.
*/
function cueAutoSlide() {
clearTimeout( autoSlideTimeout );
// Cue the next auto-slide if enabled
if( autoSlide ) {
autoSlideTimeout = setTimeout( navigateNext, autoSlide );
}
}
function navigateLeft() {
// Prioritize hiding fragments
if( availableRoutes().left && isOverviewActive() || previousFragment() === false ) {
slide( indexh - 1 );
}
}
function navigateRight() {
// Prioritize revealing fragments
if( availableRoutes().right && isOverviewActive() || nextFragment() === false ) {
slide( indexh + 1 );
}
}
function navigateUp() {
// Prioritize hiding fragments
if( availableRoutes().up && isOverviewActive() || previousFragment() === false ) {
slide( indexh, indexv - 1 );
}
}
function navigateDown() {
// Prioritize revealing fragments
if( availableRoutes().down && isOverviewActive() || nextFragment() === false ) {
slide( indexh, indexv + 1 );
}
}
/**
* Navigates backwards, prioritized in the following order:
* 1) Previous fragment
* 2) Previous vertical slide
* 3) Previous horizontal slide
*/
function navigatePrev() {
// Prioritize revealing fragments
if( previousFragment() === false ) {
if( availableRoutes().up ) {
navigateUp();
}
else {
// Fetch the previous horizontal slide, if there is one
var previousSlide = document.querySelector( HORIZONTAL_SLIDES_SELECTOR + '.past:nth-child(' + indexh + ')' );
if( previousSlide ) {
indexv = ( previousSlide.querySelectorAll( 'section' ).length + 1 ) || undefined;
indexh --;
slide();
}
}
}
}
/**
* Same as #navigatePrev() but navigates forwards.
*/
function navigateNext() {
// Prioritize revealing fragments
if( nextFragment() === false ) {
availableRoutes().down ? navigateDown() : navigateRight();
}
// If auto-sliding is enabled we need to cue up
// another timeout
cueAutoSlide();
}
// --------------------------------------------------------------------//
// ----------------------------- EVENTS -------------------------------//
// --------------------------------------------------------------------//
/**
* Handler for the document level 'keydown' event.
*
* @param {Object} event
*/
function onDocumentKeyDown( 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.altKey || event.ctrlKey || event.metaKey ) return;
var 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: isOverviewActive() ? deactivateOverview() : navigateNext(); break;
// return
case 13: isOverviewActive() ? deactivateOverview() : triggered = false; break;
// b, period
case 66: case 190: togglePause(); break;
// f
case 70: enterFullscreen(); break;
default:
triggered = false;
}
// If the input resulted in a triggered action we should prevent
// the browsers default behavior
if( triggered ) {
event.preventDefault();
}
else if ( event.keyCode === 27 && supports3DTransforms ) {
toggleOverview();
event.preventDefault();
}
// If auto-sliding is enabled we need to cue up
// another timeout
cueAutoSlide();
}
/**
* Handler for the document level 'touchstart' event,
* enables support for swipe and pinch gestures.
*/
function onDocumentTouchStart( event ) {
touch.startX = event.touches[0].clientX;
touch.startY = event.touches[0].clientY;
touch.startCount = event.touches.length;
// If there's two touches we need to memorize the distance
// between those two points to detect pinching
if( event.touches.length === 2 && config.overview ) {
touch.startSpan = distanceBetween( {
x: event.touches[1].clientX,
y: event.touches[1].clientY
}, {
x: touch.startX,
y: touch.startY
} );
}
}
/**
* Handler for the document level 'touchmove' event.
*/
function onDocumentTouchMove( event ) {
// Each touch should only trigger one action
if( !touch.handled ) {
var currentX = event.touches[0].clientX;
var currentY = event.touches[0].clientY;
// If the touch started off with two points and still has
// two active touches; test for the pinch gesture
if( event.touches.length === 2 && touch.startCount === 2 && 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.handled = 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.handled = true;
navigateLeft();
}
else if( deltaX < -touch.threshold && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
touch.handled = true;
navigateRight();
}
else if( deltaY > touch.threshold ) {
touch.handled = true;
navigateUp();
}
else if( deltaY < -touch.threshold ) {
touch.handled = true;
navigateDown();
}
event.preventDefault();
}
}
// 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 document level 'touchend' event.
*/
function onDocumentTouchEnd( event ) {
touch.handled = false;
}
/**
* Handles mouse wheel scrolling, throttled to avoid skipping
* multiple slides.
*/
function onDocumentMouseScroll( event ){
clearTimeout( mouseWheelTimeout );
mouseWheelTimeout = setTimeout( function() {
var delta = event.detail || -event.wheelDelta;
if( delta > 0 ) {
navigateNext();
}
else {
navigatePrev();
}
}, 100 );
}
/**
* Clicking on the progress bar results in a navigation to the
* closest approximate horizontal slide using this equation:
*
* ( clickX / presentationWidth ) * numberOfSlides
*/
function onProgressClick( event ) {
var slidesTotal = toArray( document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).length;
var slideIndex = Math.floor( ( event.clientX / dom.wrapper.offsetWidth ) * slidesTotal );
slide( slideIndex );
}
/**
* Handler for the window level 'hashchange' event.
*/
function onWindowHashChange( event ) {
readURL();
}
/**
* Handler for the window level 'resize' event.
*/
function onWindowResize( event ) {
layout();
}
/**
* 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( isOverviewActive() ) {
event.preventDefault();
deactivateOverview();
slide( parseInt( this.getAttribute( 'data-index-h' ) ), parseInt( this.getAttribute( 'data-index-v' ) ) );
}
}
// --------------------------------------------------------------------//
// ------------------------------- API --------------------------------//
// --------------------------------------------------------------------//
return {
initialize: initialize,
// Navigation methods
slide: slide,
left: navigateLeft,
right: navigateRight,
up: navigateUp,
down: navigateDown,
prev: navigatePrev,
next: navigateNext,
prevFragment: previousFragment,
nextFragment: nextFragment,
// Deprecated aliases
navigateTo: slide,
navigateLeft: navigateLeft,
navigateRight: navigateRight,
navigateUp: navigateUp,
navigateDown: navigateDown,
navigatePrev: navigatePrev,
navigateNext: navigateNext,
// Toggles the overview mode on/off
toggleOverview: toggleOverview,
// Adds or removes all internal event listeners (such as keyboard)
addEventListeners: addEventListeners,
removeEventListeners: removeEventListeners,
// Returns the indices of the current, or specified, slide
getIndices: getIndices,
// Returns the previous slide element, may be null
getPreviousSlide: function() {
return previousSlide;
},
// Returns the current slide element
getCurrentSlide: function() {
return currentSlide;
},
// Helper method, retrieves query string as a key/value hash
getQueryHash: function() {
var query = {};
location.search.replace( /[A-Z0-9]+?=(\w*)/gi, function(a) {
query[ a.split( '=' ).shift() ] = a.split( '=' ).pop();
} );
return query;
},
// Forward event binding to the reveal DOM element
addEventListener: function( type, listener, useCapture ) {
if( 'addEventListener' in window ) {
( dom.wrapper || document.querySelector( '.reveal' ) ).addEventListener( type, listener, useCapture );
}
},
removeEventListener: function( type, listener, useCapture ) {
if( 'addEventListener' in window ) {
( dom.wrapper || document.querySelector( '.reveal' ) ).removeEventListener( type, listener, useCapture );
}
}
};
})();