geomorillo · May 14, 2019 18:48
diff --git a/code-1.htm b/code-1.htm
 <!DOCTYPE HTML>
 <html>
 <head>
 	<title>Image Zoom With jQuery</title>
 	<style type="text/css">

 		#view {
 			border: 1px solid #333333 ;
 			overflow: hidden ;
 			position: relative ;
 			width: 400px ;
 			}

 		#image {
 			display: block ;
 			left: 0px ;
 			top: 0px ;
 			}

 		#zoom {
 			background-image: url( "./white_fade.png" ) ;
 			border: 1px solid #000000 ;
 			cursor: pointer ;
 			display: none ;
 			height: 200px ;
 			position: absolute ;
 			width: 200px ;
 			z-index: 100 ;
 			}

 	</style>
 	<script type="text/javascript" src="../jquery-1.4.js"></script>
 	<script type="text/javascript">

 		// When the WINDOW is ready, initialize. We are going with
 		// the window load rather than the document so that we
 		// know our image will be ready as well (complete with
 		// gettable dimentions).
 		$( window ).load(function(){

 			// First, let's get refernces to the elements we will
 			// be using.
 			var view = $( "#view" );
 			var image = $( "#image" );

 			// Create the ZOOM element - this will be added with
 			// Javascript since it's more of an "effect".
 			var zoom = $( "<a id='zoom'><span><br /></span></a>" );

 			// Before we start messing with the scripts, let's
 			// update the display to allow for the absolute
 			// positioning of the image and zoomer.

 			// Set an explicit height / width on the view based
 			// on the initial size of the image.
 			view.width( image.width() );
 			view.height( image.height() );

 			// Now that the view has an explicit width and height,
 			// we can change the displays for positioning.
 			image.css( "position", "absolute" );

 			// Set an exlicit height on the image (to make sure
 			// that some of the later calcualtions don't get
 			// messed up - I saw some irradic caculated-height
 			// behavior).
 			image.height( image.height() );

 			// Before we add the zoom square, we need it to match
 			// the aspect ratio of the image.
 			zoom.width( Math.floor( image.width() / 2 ) );
 			zoom.height( Math.floor( image.height() / 2 ) );

 			// Now, add the zoom square to the view.
 			view.append( zoom );


 			// ---------------------------------------------- //
 			// ---------------------------------------------- //


 			// Now that we have our UI set up physically, we need
 			// to bind the event handlers.

 			// We want to show and hide the zoom only when the
 			// user hovers over the view.
 			view.hover(
 				function( event ){
 					// Show the soom.
 					zoom.show();
 				},
 				function( event ){
 					// Hide the zoom.
 					zoom.hide();
 				}
 			);


 			// As the user mouses over the view, we can get the
 			// mouse coordinates in terms of the page; we need
 			// to be able to translate those into VIEW-based
 			// X and Y cooridates. As such, let's get the offset
 			// of the view as our base 0x0 coordinate.
 			//
 			// NOTE: We are doing this here so that we do it once,
 			// rather than every time the mouse moves.
 			viewOffset = view.offset();

 			// Get the jQuery-ed version of the window as we will
 			// need to access it's scroll offsets every time the
 			// mouse moves over the div.
 			//
 			// NOTE: This will change the change the refernce to
 			// "window" for all of the code in this closure.
 			var window = $( window );


 			// As the user moves across the view, we want to move
 			// the zoom square with them.
 			view.mousemove(
 				function( event ){
 					// Get the window scroll top; the mouse
 					// position is relative to the window, NOT
 					// the document.
 					var windowScrollTop = window.scrollTop();
 					var windowScrollLeft = window.scrollLeft();

 					// Translate the mouse X / Y into view-local
 					// coordinates that can be used to position
 					// the zoom box.
 					setZoomPosition(
 						Math.floor(
 							event.clientX - viewOffset.left + windowScrollLeft
 						),
 						Math.floor(
 							event.clientY - viewOffset.top + windowScrollTop
 						)
 					);
 				}
 			);


 			// I position the zoom box within the view based on
 			// the given view-local mouse coordinates.
 			var setZoomPosition = function( mouseLeft, mouseTop ){
 				// Ideally, we want to keep the zoom box centered
 				// on the mouse. As such, we want the given mouse
 				// left and mouse top coordiantes to be in the
 				// middle of the zoom box.
 				var zoomLeft = (mouseLeft - (zoom.width() / 2));
 				var zoomTop = (mouseTop - (zoom.height() / 2))

 				// As we move the zoom box around, however, we
 				// never want it to go out of bounds of the view.

 				// Protect the top-left bounds.
 				zoomLeft = Math.max( zoomLeft, 0 );
 				zoomTop = Math.max( zoomTop, 0 );

 				// Protect the bottom-right bounds. Because the
 				// bottom and right need to take the dimensions
 				// of the zoom box into account, be sure to use
 				// the outer width to include the border.
 				zoomLeft = Math.min(
 					zoomLeft,
 					(view.width() - zoom.outerWidth())
 					);
 				zoomTop = Math.min(
 					zoomTop,
 					(view.height() - zoom.outerHeight())
 					);

 				// Position the zoom box in the bounds of the
 				// image view box.
 				zoom.css({
 					left: (zoomLeft + "px"),
 					top: (zoomTop + "px")
 				});
 			};


 			// Now that we have the mouse movements being tracked
 			// properly, we need to track the click on the zoom to
 			// zoom in the image on demand. To do that, however,
 			// we need to start storing some information with the
 			// image so we can manipulate it as needed.
 			image.data({
 				zoomFactor: (view.width() / zoom.width()),
 				zoom: 1,
 				top: 0,
 				left: 0,
 				width: image.width(),
 				height: image.height(),
 				originalWidth: image.width(),
 				originalHeight: image.height()
 			});


 			// Now, let's attach the click event handler to the
 			// zoom box.
 			zoom.click(
 				function( event ){
 					// First, prevent the default since this is
 					// not a navigational link.
 					event.preventDefault();

 					// Let's pass the position of the zoom box
 					// off to the function that is responsible
 					// for zooming the image.
 					zoomImage(
 						zoom.position().left,
 						zoom.position().top
 					);
 				}
 			);


 			// I take the zoom box coordinates and translate them
 			// into an actual image zoom based on the existing
 			// zoom and offset of the image.
 			//
 			// NOTE: We don't care about the dimensions of the
 			// zoom box itself as those should have already been
 			// properly translated into the zoom *factor*.
 			var zoomImage = function( zoomLeft, zoomTop ){
 				// Get a reference to the image data object so we
 				// don't need to keep retreiving it.
 				var imageData = image.data();

 				// Check to see if we have reached the max zoom
 				// or if the image is currently animating.
 				// If so, just return out.
 				if (
 					(imageData.zoom == 5) ||
 					(image.is( ":animated" ))
 					){

 					// Zooming in beyond this is pointless (and
 					// can cause the browser to mis-render the
 					// image).
 					return;

 				}

 				// Scale the image up based on the zoom factor.
 				imageData.width =
 					(image.width() * imageData.zoomFactor);

 				imageData.height =
 					(image.height() * imageData.zoomFactor);

 				// Change the offset set data to re-position the
 				// 0,0 coordinate back up in the top left.
 				imageData.left =
 					((imageData.left - zoomLeft) * imageData.zoomFactor);

 				imageData.top =
 					((imageData.top - zoomTop) * imageData.zoomFactor);

 				// Increase the zoom.
 				imageData.zoom++;

 				// Animate the zoom.
 				image.animate(
 					{
 						width: imageData.width,
 						height: imageData.height,
 						left: imageData.left,
 						top: imageData.top
 					},
 					500
 				);
 			};


 			// I reset the image zoom.
 			var resetZoom = function(){
 				// Get a reference to the image data object so we
 				// don't need to keep retreiving it.
 				var imageData = image.data();

 				// Reset the image data.
 				imageData.zoom = 1;
 				imageData.top = 0;
 				imageData.left = 0;
 				imageData.width = imageData.originalWidth;
 				imageData.height = imageData.originalHeight;

 				// Animate the zoom.
 				image.animate(
 					{
 						width: imageData.width,
 						height: imageData.height,
 						left: imageData.left,
 						top: imageData.top
 					},
 					300
 				);
 			};


 			// As a final step, to make sure that the image can
 			// be zoomed out, bind the mousedown to the document.
 			$( document ).mousedown(
 				function( event ){
 					// Check to see if the view is in the event
 					// bubble chain for the mouse down. If it is,
 					// then this click was in the view or its
 					// child elements.
 					var closestView = $( event.target ).closest( "#view" );

 					// Check to see if this mouse down was in the
 					// image view.
 					if (!closestView.size()){

 						// The view was not found in the chain.
 						// This was clicked outside of the view.
 						// Reset the image zoom.
 						resetZoom();

 					}
 				}
 			);

 		});

 	</script>
 </head>
 <body>

 	<h1>
 		Image Zoom And Clip With jQuery
 	</h1>

 	<div id="view">
 		<img id="image" src="./girl.jpg" width="400" />
 	</div>

 </body>
 </html>
	<!DOCTYPE HTML>
	<html>
	<head>
	<title>Image Zoom With jQuery</title>
	<style type="text/css">

	#view {
	border: 1px solid #333333 ;
	overflow: hidden ;
	position: relative ;
	width: 400px ;
	}

	#image {
	display: block ;
	left: 0px ;
	top: 0px ;
	}

	#zoom {
	background-image: url( "./white_fade.png" ) ;
	border: 1px solid #000000 ;
	cursor: pointer ;
	display: none ;
	height: 200px ;
	position: absolute ;
	width: 200px ;
	z-index: 100 ;
	}

	</style>
	<script type="text/javascript" src="../jquery-1.4.js"></script>
	<script type="text/javascript">

	// When the WINDOW is ready, initialize. We are going with
	// the window load rather than the document so that we
	// know our image will be ready as well (complete with
	// gettable dimentions).
	$( window ).load(function(){

	// First, let's get refernces to the elements we will
	// be using.
	var view = $( "#view" );
	var image = $( "#image" );

	// Create the ZOOM element - this will be added with
	// Javascript since it's more of an "effect".
	var zoom = $( "<a id='zoom'><span><br /></span></a>" );

	// Before we start messing with the scripts, let's
	// update the display to allow for the absolute
	// positioning of the image and zoomer.

	// Set an explicit height / width on the view based
	// on the initial size of the image.
	view.width( image.width() );
	view.height( image.height() );

	// Now that the view has an explicit width and height,
	// we can change the displays for positioning.
	image.css( "position", "absolute" );

	// Set an exlicit height on the image (to make sure
	// that some of the later calcualtions don't get
	// messed up - I saw some irradic caculated-height
	// behavior).
	image.height( image.height() );

	// Before we add the zoom square, we need it to match
	// the aspect ratio of the image.
	zoom.width( Math.floor( image.width() / 2 ) );
	zoom.height( Math.floor( image.height() / 2 ) );

	// Now, add the zoom square to the view.
	view.append( zoom );


	// ---------------------------------------------- //
	// ---------------------------------------------- //


	// Now that we have our UI set up physically, we need
	// to bind the event handlers.

	// We want to show and hide the zoom only when the
	// user hovers over the view.
	view.hover(
	function( event ){
	// Show the soom.
	zoom.show();
	},
	function( event ){
	// Hide the zoom.
	zoom.hide();
	}
	);


	// As the user mouses over the view, we can get the
	// mouse coordinates in terms of the page; we need
	// to be able to translate those into VIEW-based
	// X and Y cooridates. As such, let's get the offset
	// of the view as our base 0x0 coordinate.
	//
	// NOTE: We are doing this here so that we do it once,
	// rather than every time the mouse moves.
	viewOffset = view.offset();

	// Get the jQuery-ed version of the window as we will
	// need to access it's scroll offsets every time the
	// mouse moves over the div.
	//
	// NOTE: This will change the change the refernce to
	// "window" for all of the code in this closure.
	var window = $( window );


	// As the user moves across the view, we want to move
	// the zoom square with them.
	view.mousemove(
	function( event ){
	// Get the window scroll top; the mouse
	// position is relative to the window, NOT
	// the document.
	var windowScrollTop = window.scrollTop();
	var windowScrollLeft = window.scrollLeft();

	// Translate the mouse X / Y into view-local
	// coordinates that can be used to position
	// the zoom box.
	setZoomPosition(
	Math.floor(
	event.clientX - viewOffset.left + windowScrollLeft
	),
	Math.floor(
	event.clientY - viewOffset.top + windowScrollTop
	)
	);
	}
	);


	// I position the zoom box within the view based on
	// the given view-local mouse coordinates.
	var setZoomPosition = function( mouseLeft, mouseTop ){
	// Ideally, we want to keep the zoom box centered
	// on the mouse. As such, we want the given mouse
	// left and mouse top coordiantes to be in the
	// middle of the zoom box.
	var zoomLeft = (mouseLeft - (zoom.width() / 2));
	var zoomTop = (mouseTop - (zoom.height() / 2))

	// As we move the zoom box around, however, we
	// never want it to go out of bounds of the view.

	// Protect the top-left bounds.
	zoomLeft = Math.max( zoomLeft, 0 );
	zoomTop = Math.max( zoomTop, 0 );

	// Protect the bottom-right bounds. Because the
	// bottom and right need to take the dimensions
	// of the zoom box into account, be sure to use
	// the outer width to include the border.
	zoomLeft = Math.min(
	zoomLeft,
	(view.width() - zoom.outerWidth())
	);
	zoomTop = Math.min(
	zoomTop,
	(view.height() - zoom.outerHeight())
	);

	// Position the zoom box in the bounds of the
	// image view box.
	zoom.css({
	left: (zoomLeft + "px"),
	top: (zoomTop + "px")
	});
	};


	// Now that we have the mouse movements being tracked
	// properly, we need to track the click on the zoom to
	// zoom in the image on demand. To do that, however,
	// we need to start storing some information with the
	// image so we can manipulate it as needed.
	image.data({
	zoomFactor: (view.width() / zoom.width()),
	zoom: 1,
	top: 0,
	left: 0,
	width: image.width(),
	height: image.height(),
	originalWidth: image.width(),
	originalHeight: image.height()
	});


	// Now, let's attach the click event handler to the
	// zoom box.
	zoom.click(
	function( event ){
	// First, prevent the default since this is
	// not a navigational link.
	event.preventDefault();

	// Let's pass the position of the zoom box
	// off to the function that is responsible
	// for zooming the image.
	zoomImage(
	zoom.position().left,
	zoom.position().top
	);
	}
	);


	// I take the zoom box coordinates and translate them
	// into an actual image zoom based on the existing
	// zoom and offset of the image.
	//
	// NOTE: We don't care about the dimensions of the
	// zoom box itself as those should have already been
	// properly translated into the zoom factor.
	var zoomImage = function( zoomLeft, zoomTop ){
	// Get a reference to the image data object so we
	// don't need to keep retreiving it.
	var imageData = image.data();

	// Check to see if we have reached the max zoom
	// or if the image is currently animating.
	// If so, just return out.
	if (
	(imageData.zoom == 5) \|\|
	(image.is( ":animated" ))
	){

	// Zooming in beyond this is pointless (and
	// can cause the browser to mis-render the
	// image).
	return;

	}

	// Scale the image up based on the zoom factor.
	imageData.width =
	(image.width() * imageData.zoomFactor);

	imageData.height =
	(image.height() * imageData.zoomFactor);

	// Change the offset set data to re-position the
	// 0,0 coordinate back up in the top left.
	imageData.left =
	((imageData.left - zoomLeft) * imageData.zoomFactor);

	imageData.top =
	((imageData.top - zoomTop) * imageData.zoomFactor);

	// Increase the zoom.
	imageData.zoom++;

	// Animate the zoom.
	image.animate(
	{
	width: imageData.width,
	height: imageData.height,
	left: imageData.left,
	top: imageData.top
	},
	500
	);
	};


	// I reset the image zoom.
	var resetZoom = function(){
	// Get a reference to the image data object so we
	// don't need to keep retreiving it.
	var imageData = image.data();

	// Reset the image data.
	imageData.zoom = 1;
	imageData.top = 0;
	imageData.left = 0;
	imageData.width = imageData.originalWidth;
	imageData.height = imageData.originalHeight;

	// Animate the zoom.
	image.animate(
	{
	width: imageData.width,
	height: imageData.height,
	left: imageData.left,
	top: imageData.top
	},
	300
	);
	};


	// As a final step, to make sure that the image can
	// be zoomed out, bind the mousedown to the document.
	$( document ).mousedown(
	function( event ){
	// Check to see if the view is in the event
	// bubble chain for the mouse down. If it is,
	// then this click was in the view or its
	// child elements.
	var closestView = $( event.target ).closest( "#view" );

	// Check to see if this mouse down was in the
	// image view.
	if (!closestView.size()){

	// The view was not found in the chain.
	// This was clicked outside of the view.
	// Reset the image zoom.
	resetZoom();

	}
	}
	);

	});

	</script>
	</head>
	<body>

	<h1>
	Image Zoom And Clip With jQuery
	</h1>

	<div id="view">
	<img id="image" src="./girl.jpg" width="400" />
	</div>

	</body>
	</html>