The JSFiddle code can be found at this link - https://jsfiddle.net/pmi2018/smewua0k/211/
Javascript
$('#rotate').click(function(e) {
updateImage(90, 0)
console.log("rotation");
});
$('#zoom-in').click(function() {
updateImage(0, 0.1);
console.log("Zoomed in");
});
$('#zoom-out').click(function() {
updateImage(0, -0.1);
console.log("Zoomed out");
});
var zoomLevel = 1;
var rotation = 0;
var updateImage = function(angle, zoom) {
zoomLevel += zoom;
var img_scale = ' scale(' + zoomLevel + ') ';
rotation += angle;
if (rotation == 360) {
rotation = 0;
}
var str_rotation = ' rotate(' + rotation + 'deg) ';
console.log("rotation=" + str_rotation + " scale=" + img_scale);
var img = document.getElementById('sam');
img.style.transform = img_scale + str_rotation
}
HTML
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<button type="button" id="zoom-in">zoom in</button> <button type="button" id="zoom-out">zoom out</button>
<div id=imageblock>
<img id="sam" src="http://placekitten.com/g/250/250" />
</div>
<div>
<a id="rotate" href="#">Rotate 90 degrees</a>
</div>
CSS
#imageblock {
width: 300px;
height: 300px;
border: 1px solid #000000;
overflow: auto;
display: block;
}
#sam {
transform-origin: center, center;
}
In order to keep the scaled image within the box, the origin must be set to upper left corner, and for rotating it has to be center, center. However, applying both rotation and scaling separately does not work as only the first transformation is applied.
How can I achieve both rotation and scaling of the image in the #imagebox?
Thank you!
Mark