Skip to content
Snippets Groups Projects
reveal.js 82.8 KiB
Newer Older
  • Learn to ignore specific revisions
  • 	/**
    	 * Start playback of any embedded content inside of
    	 * the targeted slide.
    	 */
    	function startEmbeddedContent( slide ) {
    
    		if( slide ) {
    
    			toArray( slide.querySelectorAll( 'video, audio' ) ).forEach( function( el ) {
    
    				if( el.hasAttribute( 'data-autoplay' ) ) {
    
    
    			// 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 ) {
    
    			toArray( slide.querySelectorAll( 'video, audio' ) ).forEach( function( el ) {
    				if( !el.hasAttribute( 'data-ignore' ) ) {
    					el.pause();
    				}
    			} );
    
    
    			// 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":""}', '*');
    				}
    			});
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	/**
    	 * 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 );
    
    				// 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 {
    
    			}
    		}
    		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 );
    			}
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	}
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	/**
    	 * Updates the page URL (hash) to reflect the current
    
    	 * @param {Number} delay The time in ms to wait before
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	 */
    
    	function writeURL( delay ) {
    
    			// 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 );
    
    				// 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;
    			}
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	}
    
    	 * Retrieves the h/v location of the current, or specified,
    
    	 *
    	 * @param {HTMLElement} slide If specified, the returned
    	 * index will be for this slide rather than the currently
    
    	 * @return {Object} { h: <int>, v: <int>, f: <int> }
    
    		// By default, return the current indices
    		var h = indexh,
    
    
    		// 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 );
    
    			var hasFragments = currentSlide.querySelectorAll( '.fragment' ).length > 0;
    			if( hasFragments ) {
    				var visibleFragments = currentSlide.querySelectorAll( '.fragment.visible' );
    
    	 * Navigate to the next slide fragment.
    
    	 * @return {Boolean} true if there was a next fragment,
    	 * false otherwise
    	 */
    
    	function nextFragment() {
    
    		if( currentSlide && config.fragments ) {
    
    			var fragments = sortFragments( currentSlide.querySelectorAll( '.fragment:not(.visible)' ) );
    
    			if( fragments.length ) {
    
    				// Find the index of the next fragment
    				var index = fragments[0].getAttribute( 'data-fragment-index' );
    
    				// Find all fragments with the same index
    				fragments = currentSlide.querySelectorAll( '.fragment[data-fragment-index="'+ index +'"]' );
    
    				toArray( fragments ).forEach( function( element ) {
    					element.classList.add( 'visible' );
    
    				// Notify subscribers of the change
    				dispatchEvent( 'fragmentshown', { fragment: fragments[0], fragments: fragments } );
    
    
    	}
    
    	/**
    	 * Navigate to the previous slide fragment.
    
    	 * @return {Boolean} true if there was a previous fragment,
    	 * false otherwise
    	 */
    	function previousFragment() {
    
    		if( currentSlide && config.fragments ) {
    
    			var fragments = sortFragments( currentSlide.querySelectorAll( '.fragment.visible' ) );
    
    			if( fragments.length ) {
    
    				// Find the index of the previous fragment
    				var index = fragments[ fragments.length - 1 ].getAttribute( 'data-fragment-index' );
    
    				// Find all fragments with the same index
    				fragments = currentSlide.querySelectorAll( '.fragment[data-fragment-index="'+ index +'"]' );
    
    				toArray( fragments ).forEach( function( f ) {
    					f.classList.remove( 'visible' );
    
    				// Notify subscribers of the change
    				dispatchEvent( 'fragmenthidden', { fragment: fragments[0], fragments: fragments } );
    
    
    	/**
    	 * Cues a new automated slide if enabled in the config.
    	 */
    
    			// If the current slide has a data-autoslide use that,
    			// otherwise use the config.autoSlide value
    			var slideAutoSlide = currentSlide.getAttribute( 'data-autoslide' );
    			if( slideAutoSlide ) {
    				autoSlide = parseInt( slideAutoSlide, 10 );
    			}
    			else {
    				autoSlide = config.autoSlide;
    			}
    
    			// 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 );
    
    	function pauseAutoSlide() {
    
    		autoSlidePaused = true;
    		clearTimeout( autoSlideTimeout );
    
    		if( autoSlidePlayer ) {
    			autoSlidePlayer.setPlaying( false );
    		}
    
    	}
    
    	function resumeAutoSlide() {
    
    		autoSlidePaused = false;
    		cueAutoSlide();
    
    	}
    
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	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 ) {
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	}
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	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 ) {
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	}
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	function navigateUp() {
    
    		// Prioritize hiding fragments
    
    		if( ( isOverview() || previousFragment() === false ) && availableRoutes().up ) {
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	}
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	function navigateDown() {
    
    		// Prioritize revealing fragments
    
    		if( ( isOverview() || nextFragment() === false ) && availableRoutes().down ) {
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	}
    
    
    	/**
    	 * 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 + ')' );
    
    Rick Lupton's avatar
    Rick Lupton committed
    					var v = ( previousSlide.querySelectorAll( 'section' ).length - 1 ) || undefined;
    					var h = indexh - 1;
    
    	}
    
    	/**
    	 * 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
    
    	// --------------------------------------------------------------------//
    	// ----------------------------- EVENTS -------------------------------//
    	// --------------------------------------------------------------------//
    
    
    	/**
    	 * Called by all event handlers that are based on user
    	 * input.
    	 */
    	function onUserInput( event ) {
    
    		if( config.autoSlideStoppable ) {
    
    
    	/**
    	 * Handler for the document level 'keydown' 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
    
    Remy Bach's avatar
    Remy Bach committed
    		if( hasFocus || (event.shiftKey && event.keyCode !== 32) || event.altKey || event.ctrlKey || event.metaKey ) return;
    
    		// While paused only allow "unpausing" keyboard events (b and .)
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    		if( isPaused() && [66,190,191].indexOf( event.keyCode ) === -1 ) {
    
    		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;
    				// b, period, Logitech presenter tools "black screen" button
    				case 66: case 190: case 191: 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 || event.keyCode === 79 ) && features.transforms3d ) {
    
    			if( dom.preview ) {
    				closePreview();
    			}
    			else {
    				toggleOverview();
    			}
    
    		// If auto-sliding is enabled we need to cue up
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	 * 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 ) {
    
    			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;
    
    				else if( deltaX < -touch.threshold && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
    
    					touch.captured = true;
    
    					touch.captured = true;
    
    					touch.captured = true;
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    				// If we're embedded, only block touch events if they have
    				// triggered an action
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    					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.touches = [{ clientX: event.clientX, clientY: event.clientY }];
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    			onTouchStart( event );
    
    		}
    
    	}
    
    	/**
    	 * Convert pointer move to touch move.
    	 */
    	function onPointerMove( event ) {
    
    		if( event.pointerType === event.MSPOINTER_TYPE_TOUCH ) {
    			event.touches = [{ clientX: event.clientX, clientY: event.clientY }];
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    			onTouchMove( event );
    
    		}
    
    	}
    
    	/**
    	 * Convert pointer up to touch end.
    	 */
    	function onPointerUp( event ) {
    
    		if( event.pointerType === event.MSPOINTER_TYPE_TOUCH ) {
    			event.touches = [{ clientX: event.clientX, clientY: event.clientY }];
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    			onTouchEnd( event );
    
    	 * Handles mouse wheel scrolling, throttled to avoid skipping
    
    	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
    	 */
    
    		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 ) {
    
    	/**
    	 * Handler for the window level 'resize' event.
    	 */
    	function onWindowResize( event ) {
    
    	/**
    	 * 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() ) {
    
    			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 ) {
    
    		this.size = 50;
    		this.thickness = 3;
    		this.playing = false;
    		this.progress = 0;
    
    		this.container = container;
    		this.progressCheck = progressCheck;
    
    		this.canvas = document.createElement( 'canvas' );
    		this.canvas.className = 'playback';
    		this.canvas.width = this.size;
    		this.canvas.height = this.size;
    		this.context = this.canvas.getContext( '2d' );
    
    		this.container.appendChild( this.canvas );
    
    		this.render();
    
    	}
    
    	Playback.prototype.setPlaying = function( value ) {
    
    		this.playing = value;
    
    		// Render instantly
    		this.render();
    
    		// Start repainting if we're playing
    		if( this.playing ) {
    
    	Playback.prototype.animate = function() {
    
    
    		this.progress = this.progressCheck();
    		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;
    
    
    		var radius = ( this.size / 2 ) - this.thickness,
    			x = this.size / 2,
    			y = this.size / 2;
    
    
    		var iconSize = 14;
    
    
    		var startAngle = - Math.PI / 2;
    
    		var endAngle = startAngle + ( progress * ( Math.PI * 2 ) );
    
    
    		this.context.save();
    		this.context.clearRect( 0, 0, this.size, this.size );
    
    		// 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();
    
    
    		// 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 --------------------------------//
    	// --------------------------------------------------------------------//
    
    
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    	return {
    
    Hakim El Hattab's avatar
    Hakim El Hattab committed
    		sync: sync,
    
    		// Navigation methods
    		slide: slide,
    		left: navigateLeft,
    		right: navigateRight,
    		up: navigateUp,
    		down: navigateDown,
    		prev: navigatePrev,
    		next: navigateNext,