How to draw SVG image on canvas with Konva

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How to show SVG image on canvas?

It has not always been possible for browsers to draw *.svg images onto the canvas. However, the situation has improved and you currently have several options available if you want to render a vector image with Konva:

Option 1: Use Konva.Path

Use Konva.Path. This method is good for simple path shapes. If you have a large SVG with many paths you, you may need to split it manually into several Konva.Path shapes.

Option 2: Use Konva.Image

Use Konva.Image shape with svg image

Konva.Image.fromURL('/image.svg', (image) => {
  layer.add(image);
  layer.draw();
})

This method works well in many cases, but is not fully cross-compatible. For example, some SVG may not be visible in the Firefox browser (there is a workaround for that case).

Option 3: Use an external library to render SVG to canvas

Use an external library (for example, canvg) to draw the SVG into the <canvas> element. And then use that canvas for Konva.Image.

This method has been tested in at least one large production app, with proven reliability and rendering accuracy.

Demo

Below is a demo that shows drawing natively and with a library.

Konva GIF demoview raw
<!DOCTYPE html>
<html>
  <head>
    <script src="https://unpkg.com/[email protected]/konva.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/canvg/dist/browser/canvg.min.js"></script>
    <meta charset="utf-8" />
    <title>Konva SVG Demo</title>
    <style>
      body {
        margin: 0;
        padding: 0;
        overflow: hidden;
        background-color: #f0f0f0;
      }
    </style>
  </head>

  <body>
    <div id="container"></div>
    <script>
      var width = window.innerWidth;
      var height = window.innerHeight;

      var stage = new Konva.Stage({
        container: 'container',
        width: width,
        height: height
      });

      var layer = new Konva.Layer();
      stage.add(layer);

      var SOURCE = '/assets/tiger.svg';
      // try to draw SVG natively
      Konva.Image.fromURL(SOURCE, imageNode => {
        layer.add(imageNode);
        imageNode.setAttrs({
          width: 150,
          height: 150
        });
        layer.batchDraw();
      });

      // draw svg with external library
      var canvas = document.createElement('canvas');
      canvg(canvas, SOURCE, {
        renderCallback: function() {
          var image = new Konva.Image({
            image: canvas,
            x: 200,
            width: 150,
            height: 150
          });
          layer.add(image);
          layer.batchDraw();
        }
      });
    </script>
  </body>
</html>
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