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htmlcssmagnificationmagnify

Magnifiing effect over a image with mouse hover with HTML/CSS


Is it posibble to achieve this effect just with html and css? In the example image you can see a magnified rounded area (from a higher resolution source picture) where the mouse is hovering. It doesn't to be rounded area or to have borders.

example of desired Magnifiing effect over a image with mouse hover with HTML/CSS

In this site example you can see a good example (but it uses jquery and i don't know where to put this code in my web page)

can anyone here give me a clue how to start coding this? (in case that is was doable). Many thanks!


Solution

  • To use the second example is simple Only copy the html in your html page, the css in your css page and the jquery code in your html page like this

    <script type="text/javascript">$(document).ready(function(){
    
    var native_width = 0;
    var native_height = 0;
    
    //Now the mousemove function
    $(".magnify").mousemove(function(e){
        //When the user hovers on the image, the script will first calculate
        //the native dimensions if they don't exist. Only after the native dimensions
        //are available, the script will show the zoomed version.
        if(!native_width && !native_height)
        {
            //This will create a new image object with the same image as that in .small
            //We cannot directly get the dimensions from .small because of the 
            //width specified to 200px in the html. To get the actual dimensions we have
            //created this image object.
            var image_object = new Image();
            image_object.src = $(".small").attr("src");
    
            //This code is wrapped in the .load function which is important.
            //width and height of the object would return 0 if accessed before 
            //the image gets loaded.
            native_width = image_object.width;
            native_height = image_object.height;
        }
        else
        {
            //x/y coordinates of the mouse
            //This is the position of .magnify with respect to the document.
            var magnify_offset = $(this).offset();
            //We will deduct the positions of .magnify from the mouse positions with
            //respect to the document to get the mouse positions with respect to the 
            //container(.magnify)
            var mx = e.pageX - magnify_offset.left;
            var my = e.pageY - magnify_offset.top;
    
            //Finally the code to fade out the glass if the mouse is outside the container
            if(mx < $(this).width() && my < $(this).height() && mx > 0 && my > 0)
            {
                $(".large").fadeIn(100);
            }
            else
            {
                $(".large").fadeOut(100);
            }
            if($(".large").is(":visible"))
            {
                //The background position of .large will be changed according to the position
                //of the mouse over the .small image. So we will get the ratio of the pixel
                //under the mouse pointer with respect to the image and use that to position the 
                //large image inside the magnifying glass
                var rx = Math.round(mx/$(".small").width()*native_width - $(".large").width()/2)*-1;
                var ry = Math.round(my/$(".small").height()*native_height - $(".large").height()/2)*-1;
                var bgp = rx + "px " + ry + "px";
    
                //Time to move the magnifying glass with the mouse
                var px = mx - $(".large").width()/2;
                var py = my - $(".large").height()/2;
                //Now the glass moves with the mouse
                //The logic is to deduct half of the glass's width and height from the 
                //mouse coordinates to place it with its center at the mouse coordinates
    
                //If you hover on the image now, you should see the magnifying glass in action
                $(".large").css({left: px, top: py, backgroundPosition: bgp});
            }
        }
    })
    

    }

    Use this code between and in your html page

    <script src="//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>