aboutsummaryrefslogtreecommitdiff
path: root/lib
diff options
context:
space:
mode:
Diffstat (limited to 'lib')
-rw-r--r--lib/js/zoom.js257
1 files changed, 257 insertions, 0 deletions
diff --git a/lib/js/zoom.js b/lib/js/zoom.js
new file mode 100644
index 0000000..7fba523
--- /dev/null
+++ b/lib/js/zoom.js
@@ -0,0 +1,257 @@
+/*!
+ * zoom.js 0.2 (modified version for use with reveal.js)
+ * http://lab.hakim.se/zoom-js
+ * MIT licensed
+ *
+ * Copyright (C) 2011-2012 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;
+
+ var currentOptions = null;
+
+ // 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, prioritizes use of CSS3
+ * transforms but falls back on zoom for IE.
+ *
+ * @param {Number} pageOffsetX
+ * @param {Number} pageOffsetY
+ * @param {Number} elementOffsetX
+ * @param {Number} elementOffsetY
+ * @param {Number} scale
+ */
+ function magnify( pageOffsetX, pageOffsetY, elementOffsetX, elementOffsetY, scale ) {
+
+ if( supportsTransforms ) {
+ var origin = pageOffsetX +'px '+ pageOffsetY +'px',
+ transform = 'translate('+ -elementOffsetX +'px,'+ -elementOffsetY +'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 all values
+ 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 = '';
+ }
+ // Apply scale
+ else {
+ document.body.style.position = 'relative';
+ document.body.style.left = ( - ( pageOffsetX + elementOffsetX ) / scale ) + 'px';
+ document.body.style.top = ( - ( pageOffsetY + elementOffsetY ) / scale ) + 'px';
+ document.body.style.width = ( scale * 100 ) + '%';
+ document.body.style.height = ( scale * 100 ) + '%';
+ document.body.style.zoom = scale;
+ }
+ }
+
+ level = scale;
+ }
+
+ /**
+ * 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.pageXYffset
+ }
+ }
+
+ 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;
+
+ options.width = options.element.getBoundingClientRect().width + ( padding * 2 );
+ options.height = options.element.getBoundingClientRect().height + ( padding * 2 );
+ options.x = options.element.getBoundingClientRect().left - padding;
+ options.y = options.element.getBoundingClientRect().top - padding;
+ }
+
+ // 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;
+
+ var scrollOffset = getScrollOffset();
+
+ if( options.element ) {
+ scrollOffset.x -= ( window.innerWidth - ( options.width * options.scale ) ) / 2;
+ }
+
+ magnify( scrollOffset.x, scrollOffset.y, options.x, options.y, 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 );
+
+ }
+ }
+
+ currentOptions = options;
+ }
+ },
+
+ /**
+ * Resets the document zoom state to its default.
+ */
+ out: function() {
+ clearTimeout( panEngageTimeout );
+ clearInterval( panUpdateInterval );
+
+ var scrollOffset = getScrollOffset();
+
+ if( currentOptions && currentOptions.element ) {
+ scrollOffset.x -= ( window.innerWidth - ( currentOptions.width * currentOptions.scale ) ) / 2;
+ }
+
+ magnify( scrollOffset.x, scrollOffset.y, 0, 0, 1 );
+
+ level = 1;
+ },
+
+ // Alias
+ magnify: function( options ) { this.to( options ) },
+ reset: function() { this.out() },
+
+ zoomLevel: function() {
+ return level;
+ }
+ }
+
+})();
+
+
+
+
+// Custom reveal.js integration
+(function(){
+ var modifierIsActive = false;
+
+ function updateKeyFlag( event ) {
+ modifierIsActive = event.altKey;
+ }
+
+ document.addEventListener( 'keypress', updateKeyFlag, false );
+ document.addEventListener( 'keydown', updateKeyFlag, false );
+ document.addEventListener( 'keyup', updateKeyFlag, false );
+
+ document.querySelector( '.reveal' ).addEventListener( 'click', function( event ) {
+ if( modifierIsActive ) {
+ event.preventDefault();
+ zoom.to({ element: event.target, pan: false });
+ }
+ } );
+})();
+
generated by cgit v1.2.3 (git 2.45.0) at 2024-11-23 10:13:38 +0000