presentations

zoom.js (7821B)

---

 // Custom reveal.js integration
 var RevealZoom = (function(){
 
 	return {
 		init: function() {
 
 			Reveal.getRevealElement().addEventListener( 'mousedown', function( event ) {
 				var defaultModifier = /Linux/.test( window.navigator.platform ) ? 'ctrl' : 'alt';
 
 				var modifier = ( Reveal.getConfig().zoomKey ? Reveal.getConfig().zoomKey : defaultModifier ) + 'Key';
 				var zoomLevel = ( Reveal.getConfig().zoomLevel ? Reveal.getConfig().zoomLevel : 2 );
 
 				if( event[ modifier ] && !Reveal.isOverview() ) {
 					event.preventDefault();
 
 					zoom.to({
 						x: event.clientX,
 						y: event.clientY,
 						scale: zoomLevel,
 						pan: false
 					});
 				}
 			} );
 
 		}
 	}
 
 })();
 
 Reveal.registerPlugin( 'zoom', RevealZoom );
 
 /*!
  * zoom.js 0.3 (modified for use with reveal.js)
  * http://lab.hakim.se/zoom-js
  * MIT licensed
  *
  * Copyright (C) 2011-2014 Hakim El Hattab, http://hakim.se
  */
 var zoom = (function(){
 
 	// The current zoom level (scale)
 	var level = 1;
 
 	// The current mouse position, used for panning
 	var mouseX = 0,
 		mouseY = 0;
 
 	// Timeout before pan is activated
 	var panEngageTimeout = -1,
 		panUpdateInterval = -1;
 
 	// Check for transform support so that we can fallback otherwise
 	var supportsTransforms = 	'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;
 
 	if( supportsTransforms ) {
 		// The easing that will be applied when we zoom in/out
 		document.body.style.transition = 'transform 0.8s ease';
 		document.body.style.OTransition = '-o-transform 0.8s ease';
 		document.body.style.msTransition = '-ms-transform 0.8s ease';
 		document.body.style.MozTransition = '-moz-transform 0.8s ease';
 		document.body.style.WebkitTransition = '-webkit-transform 0.8s ease';
 	}
 
 	// Zoom out if the user hits escape
 	document.addEventListener( 'keyup', function( event ) {
 		if( level !== 1 && event.keyCode === 27 ) {
 			zoom.out();
 		}
 	} );
 
 	// Monitor mouse movement for panning
 	document.addEventListener( 'mousemove', function( event ) {
 		if( level !== 1 ) {
 			mouseX = event.clientX;
 			mouseY = event.clientY;
 		}
 	} );
 
 	/**
 	 * Applies the CSS required to zoom in, prefers the use of CSS3
 	 * transforms but falls back on zoom for IE.
 	 *
 	 * @param {Object} rect
 	 * @param {Number} scale
 	 */
 	function magnify( rect, scale ) {
 
 		var scrollOffset = getScrollOffset();
 
 		// Ensure a width/height is set
 		rect.width = rect.width || 1;
 		rect.height = rect.height || 1;
 
 		// Center the rect within the zoomed viewport
 		rect.x -= ( window.innerWidth - ( rect.width * scale ) ) / 2;
 		rect.y -= ( window.innerHeight - ( rect.height * scale ) ) / 2;
 
 		if( supportsTransforms ) {
 			// Reset
 			if( scale === 1 ) {
 				document.body.style.transform = '';
 				document.body.style.OTransform = '';
 				document.body.style.msTransform = '';
 				document.body.style.MozTransform = '';
 				document.body.style.WebkitTransform = '';
 			}
 			// Scale
 			else {
 				var origin = scrollOffset.x +'px '+ scrollOffset.y +'px',
 					transform = 'translate('+ -rect.x +'px,'+ -rect.y +'px) scale('+ scale +')';
 
 				document.body.style.transformOrigin = origin;
 				document.body.style.OTransformOrigin = origin;
 				document.body.style.msTransformOrigin = origin;
 				document.body.style.MozTransformOrigin = origin;
 				document.body.style.WebkitTransformOrigin = origin;
 
 				document.body.style.transform = transform;
 				document.body.style.OTransform = transform;
 				document.body.style.msTransform = transform;
 				document.body.style.MozTransform = transform;
 				document.body.style.WebkitTransform = transform;
 			}
 		}
 		else {
 			// Reset
 			if( scale === 1 ) {
 				document.body.style.position = '';
 				document.body.style.left = '';
 				document.body.style.top = '';
 				document.body.style.width = '';
 				document.body.style.height = '';
 				document.body.style.zoom = '';
 			}
 			// Scale
 			else {
 				document.body.style.position = 'relative';
 				document.body.style.left = ( - ( scrollOffset.x + rect.x ) / scale ) + 'px';
 				document.body.style.top = ( - ( scrollOffset.y + rect.y ) / scale ) + 'px';
 				document.body.style.width = ( scale * 100 ) + '%';
 				document.body.style.height = ( scale * 100 ) + '%';
 				document.body.style.zoom = scale;
 			}
 		}
 
 		level = scale;
 
 		if( document.documentElement.classList ) {
 			if( level !== 1 ) {
 				document.documentElement.classList.add( 'zoomed' );
 			}
 			else {
 				document.documentElement.classList.remove( 'zoomed' );
 			}
 		}
 	}
 
 	/**
 	 * Pan the document when the mosue cursor approaches the edges
 	 * of the window.
 	 */
 	function pan() {
 		var range = 0.12,
 			rangeX = window.innerWidth * range,
 			rangeY = window.innerHeight * range,
 			scrollOffset = getScrollOffset();
 
 		// Up
 		if( mouseY < rangeY ) {
 			window.scroll( scrollOffset.x, scrollOffset.y - ( 1 - ( mouseY / rangeY ) ) * ( 14 / level ) );
 		}
 		// Down
 		else if( mouseY > window.innerHeight - rangeY ) {
 			window.scroll( scrollOffset.x, scrollOffset.y + ( 1 - ( window.innerHeight - mouseY ) / rangeY ) * ( 14 / level ) );
 		}
 
 		// Left
 		if( mouseX < rangeX ) {
 			window.scroll( scrollOffset.x - ( 1 - ( mouseX / rangeX ) ) * ( 14 / level ), scrollOffset.y );
 		}
 		// Right
 		else if( mouseX > window.innerWidth - rangeX ) {
 			window.scroll( scrollOffset.x + ( 1 - ( window.innerWidth - mouseX ) / rangeX ) * ( 14 / level ), scrollOffset.y );
 		}
 	}
 
 	function getScrollOffset() {
 		return {
 			x: window.scrollX !== undefined ? window.scrollX : window.pageXOffset,
 			y: window.scrollY !== undefined ? window.scrollY : window.pageYOffset
 		}
 	}
 
 	return {
 		/**
 		 * Zooms in on either a rectangle or HTML element.
 		 *
 		 * @param {Object} options
 		 *   - element: HTML element to zoom in on
 		 *   OR
 		 *   - x/y: coordinates in non-transformed space to zoom in on
 		 *   - width/height: the portion of the screen to zoom in on
 		 *   - scale: can be used instead of width/height to explicitly set scale
 		 */
 		to: function( options ) {
 
 			// Due to an implementation limitation we can't zoom in
 			// to another element without zooming out first
 			if( level !== 1 ) {
 				zoom.out();
 			}
 			else {
 				options.x = options.x || 0;
 				options.y = options.y || 0;
 
 				// If an element is set, that takes precedence
 				if( !!options.element ) {
 					// Space around the zoomed in element to leave on screen
 					var padding = 20;
 					var bounds = options.element.getBoundingClientRect();
 
 					options.x = bounds.left - padding;
 					options.y = bounds.top - padding;
 					options.width = bounds.width + ( padding * 2 );
 					options.height = bounds.height + ( padding * 2 );
 				}
 
 				// If width/height values are set, calculate scale from those values
 				if( options.width !== undefined && options.height !== undefined ) {
 					options.scale = Math.max( Math.min( window.innerWidth / options.width, window.innerHeight / options.height ), 1 );
 				}
 
 				if( options.scale > 1 ) {
 					options.x *= options.scale;
 					options.y *= options.scale;
 
 					magnify( options, options.scale );
 
 					if( options.pan !== false ) {
 
 						// Wait with engaging panning as it may conflict with the
 						// zoom transition
 						panEngageTimeout = setTimeout( function() {
 							panUpdateInterval = setInterval( pan, 1000 / 60 );
 						}, 800 );
 
 					}
 				}
 			}
 		},
 
 		/**
 		 * Resets the document zoom state to its default.
 		 */
 		out: function() {
 			clearTimeout( panEngageTimeout );
 			clearInterval( panUpdateInterval );
 
 			magnify( { x: 0, y: 0 }, 1 );
 
 			level = 1;
 		},
 
 		// Alias
 		magnify: function( options ) { this.to( options ) },
 		reset: function() { this.out() },
 
 		zoomLevel: function() {
 			return level;
 		}
 	}
 
 })();