JSFiddle - React, Tailwind, and code Playground
HTML
<div id="container">
<div class="canvasContainer"></div>
<div class="content main">
<div class="action crop">Crop</div>
<div class="transformCropLimit">
<div class="transformCropInner">
<div class="mediaBlock">
<img src="http://image.vsco.co/1/55210eb4aceed3144059/57f2471df662677e548b4568/300x400/25e7b55c-6ed9-490c-95c2-6d69520eb7bd1835072132.jpg">
</div>
</div>
</div>
</div>
</div>
CSS
.mediaBlock {
position: relative;
display: block;
overflow: hidden;
}
.mediaBlock img {
max-width: 100%;
}
.transformCropLimit {
position: relative;
top: 20px;
left: 20px;
width: 200px;
height: 200px;
border: 1px solid blue;
}
.transformCropInner {
width: 100px;
cursor: pointer;
position: relative;
top: 10px;
left: 100px;
}
.transformCropInner.rotate {
transform: rotate(9-2deg);
-ms-transform: rotate(-20deg); /* IE 9 */
-moz-transform: rotate(-20deg); /* Firefox */
-webkit-transform: rotate(-20deg); /* Safari and Chrome */
-o-transform: rotate(-20deg); /* Opera */
}
JavaScript
var crop = function() {
var transformMediaBlock = $('.mediaBlock');
var transformCropInner = $('.transformCropInner');
var transformCropLimit = $('.transformCropLimit');
var canvasContainer = $('.canvasContainer')
var limitLeft = transformCropLimit.offset().left;
var limitTop = transformCropLimit.offset().top;
var limitRight = limitLeft + transformCropLimit.width();
var limitBottom = limitTop + transformCropLimit.height();
var imageRatio = transformMediaBlock.find('img')[0].naturalWidth/transformMediaBlock.find('img').width();
// draw rotate image
var deg2Rad = Math.PI/180;
var rotateDegree = -20;
$('<canvas/>',{'class':'rotate'}).appendTo($(canvasContainer));
var canvas = $('.canvasContainer canvas')[0];
var ctx = canvas.getContext("2d");
var width = 0;
var height = 0;
var diagonal = 0;
var angleInDegrees = 0;
width = transformMediaBlock.find('img')[0].naturalWidth;
height = transformMediaBlock.find('img')[0].naturalHeight;
diagonal = Math.sqrt(Math.pow(width,2)+Math.pow(height,2));
ctx.canvas.width = diagonal;
ctx.canvas.height = diagonal;
ctx.clearRect(0,0,canvas.width,canvas.height);
ctx.save();
ctx.translate(diagonal/2,diagonal/2);
ctx.rotate(0*Math.PI/180);
ctx.drawImage(transformMediaBlock.find('img')[0],-width/2,-height/2);
ctx.restore();
var drawRotated = function(degrees){
ctx.clearRect(0,0,canvas.width,canvas.height);
ctx.save();
ctx.translate(diagonal/2,diagonal/2);
ctx.rotate(degrees*Math.PI/180);
ctx.drawImage(transformMediaBlock.find('img')[0],-width/2,-height/2);
ctx.restore();
};
drawRotated(rotateDegree);
// draw crop rotate image
var imageLeft = transformMediaBlock.find('img').offset().left;
var imageTop = transformMediaBlock.find('img').offset().top;
var imageRight = imageLeft + transformMediaBlock.find('img').width();
var imageBottom = imageTop + transformMediaBlock.find('img').height();
if (limitLeft <= imageLeft) {
...