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javascript - fabric.js : How to make an image in the shape of a oval with strokes shadow etc?

I have been trying to show a image as oval shape but no luck.

below is my code snippet, which works for circle but there are gaps when we are converting image from rectangle to ellipse

how can i add both rx, ry in html canvas? this is how current code converts my rectangle image to ellipse, there are gaps in height & width they are not accurate.

sample output image:

enter image description here

fabric.util.loadImage(imageURL, function (img) {
      var oImg = new fabric.Image(img);


      if (slot.image_shape == "ellipse") {
        let shadow = (options && options.shadow) || {
          affectStroke: true,
        };
        const radius =
          oImg.width < oImg.height ? oImg.width / 2 : oImg.height / 2;
        oImg.set({
          clipTo: function (ctx) {
            return ctx.arc(0, 0, radius, 0, Math.PI * 2, false);
          },
        });
      }
question from:https://stackoverflow.com/questions/65916009/fabric-js-how-to-make-an-image-in-the-shape-of-a-oval-with-strokes-shadow-etc

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1 Answer

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Unfortunately I'm not aware of what fabric.js version you're actually using but from 2.4.0 onwards you can use the clipPath property. In conjunction with the Ellipse class you can directly use an ellipsoidal shape as a mask - which let's you directly enter values for rx and ry instead of just a radius.

Here's an example:

var canvas = window._canvas = new fabric.Canvas('canvas');

fabric.Image.fromURL('https://picsum.photos/200/200', function(img) {
  img.set({
    hasControls: false,
    hasBorders: false,
    left: 0,
    top: 0,
    clipPath: new fabric.Ellipse({
      rx: 100,
      ry: 50,
      originX: 'center',
      originY: 'center',
    }),
  });
  canvas.add(img);
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/fabric.js/4.2.0/fabric.min.js"></script>
<canvas id="canvas" width="400" height="400" class="canvas"></canvas>

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