Zoom part of webpage independently from the rest of the page

Question

I was wondering if it would be possible to isolate a part of a webpage (?) to be zoomable independently from the rest of the page, a bit like the way you can interact with google maps. Thank you and good day, Felix

Answer 1

I think it'll help you. https://www.w3schools.com/howto/howto_js_image_zoom.asp

 function imageZoom(imgID, resultID) { var img, lens, result, cx, cy; img = document.getElementById(imgID); result = document.getElementById(resultID); /*create lens:*/ lens = document.createElement("DIV"); lens.setAttribute("class", "img-zoom-lens"); /*insert lens:*/ img.parentElement.insertBefore(lens, img); /*calculate the ratio between result DIV and lens:*/ cx = result.offsetWidth / lens.offsetWidth; cy = result.offsetHeight / lens.offsetHeight; /*set background properties for the result DIV:*/ result.style.backgroundImage = "url('" + img.src + "')"; result.style.backgroundSize = (img.width * cx) + "px " + (img.height * cy) + "px"; /*execute a function when someone moves the cursor over the image, or the lens:*/ lens.addEventListener("mousemove", moveLens); img.addEventListener("mousemove", moveLens); /*and also for touch screens:*/ lens.addEventListener("touchmove", moveLens); img.addEventListener("touchmove", moveLens); function moveLens(e) { var pos, x, y; /*prevent any other actions that may occur when moving over the image:*/ e.preventDefault(); /*get the cursor's x and y positions:*/ pos = getCursorPos(e); /*calculate the position of the lens:*/ x = pos.x - (lens.offsetWidth / 2); y = pos.y - (lens.offsetHeight / 2); /*prevent the lens from being positioned outside the image:*/ if (x > img.width - lens.offsetWidth) {x = img.width - lens.offsetWidth;} if (x < 0) {x = 0;} if (y > img.height - lens.offsetHeight) {y = img.height - lens.offsetHeight;} if (y < 0) {y = 0;} /*set the position of the lens:*/ lens.style.left = x + "px"; lens.style.top = y + "px"; /*display what the lens "sees":*/ result.style.backgroundPosition = "-" + (x * cx) + "px -" + (y * cy) + "px"; } function getCursorPos(e) { var a, x = 0, y = 0; e = e || window.event; /*get the x and y positions of the image:*/ a = img.getBoundingClientRect(); /*calculate the cursor's x and y coordinates, relative to the image:*/ x = e.pageX - a.left; y = e.pageY - a.top; /*consider any page scrolling:*/ x = x - window.pageXOffset; y = y - window.pageYOffset; return {x : x, y : y}; } } imageZoom("myimage", "myresult"); 

 * {box-sizing: border-box;} .img-zoom-container { position: relative; } .img-zoom-lens { position: absolute; border: 1px solid #d4d4d4; /*set the size of the lens:*/ width: 40px; height: 40px; } .img-zoom-result { border: 1px solid #d4d4d4; /*set the size of the result div:*/ width: 300px; height: 300px; } 

 <h1>Image Zoom</h1> <p>Mouse over the image:</p> <div class="img-zoom-container"> <img id="myimage" src="https://www.w3schools.com/howto/img_girl.jpg" width="300" height="240"> <div id="myresult" class="img-zoom-result"></div> </div> 

Answer 2

Not knowing much about you goal, attaching an event listener to your target div/element for scroll/touch events would be the place to start.

In response to the events you would adjust the css of the element. You could either adjust width / height or adjust transform:scale() . The latter would probably be better performance wise as it would limit page layout (re)calculations.