How to draw SVG image on canvas with Konva

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.Image

In most of the cases you can use *.svg image the same way as any other image such as *.png or *.jpg. You can use Konva.Image shape.

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

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 2: 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 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.

Vanilla

import Konva from 'konva';

// Load canvg library
const script = document.createElement('script');
script.src = 'https://cdn.jsdelivr.net/npm/canvg/dist/browser/canvg.min.js';
document.head.appendChild(script);

const stage = new Konva.Stage({
  container: 'container',
  width: window.innerWidth,
  height: window.innerHeight,
});

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

const SOURCE = 'https://konvajs.org/assets/tiger.svg';

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

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

Open Sandbox

React

import React from 'react';
import { Stage, Layer, Image } from 'react-konva';

const SOURCE = '/assets/tiger.svg';

const App = () => {
  const [nativeImage, setNativeImage] = React.useState(null);
  const [canvgImage, setCanvgImage] = React.useState(null);

  React.useEffect(() => {
    // Load native SVG
    const image = new window.Image();
    image.src = SOURCE;
    image.onload = () => {
      setNativeImage(image);
    };

    // Load canvg library and render SVG
    const script = document.createElement('script');
    script.src = 'https://cdn.jsdelivr.net/npm/canvg/dist/browser/canvg.min.js';
    script.onload = () => {
      const canvas = document.createElement('canvas');
      canvg(canvas, SOURCE, {
        renderCallback: function () {
          setCanvgImage(canvas);
        },
      });
    };
    document.head.appendChild(script);

    return () => {
      script.remove();
    };
  }, []);

  return (
    <Stage width={window.innerWidth} height={window.innerHeight}>
      <Layer>
        {nativeImage && (
          <Image
            image={nativeImage}
            width={150}
            height={150}
          />
        )}
        {canvgImage && (
          <Image
            image={canvgImage}
            x={200}
            width={150}
            height={150}
          />
        )}
      </Layer>
    </Stage>
  );
};

export default App;

Open Sandbox

Vue

<template>
  <v-stage :config="stageConfig">
    <v-layer>
      <v-image
        v-if="nativeImage"
        :config="{
          image: nativeImage,
          width: 150,
          height: 150
        }"
      />
      <v-image
        v-if="canvgImage"
        :config="{
          image: canvgImage,
          x: 200,
          width: 150,
          height: 150
        }"
      />
    </v-layer>
  </v-stage>
</template>

<script setup>
import { ref, onMounted, onUnmounted } from 'vue';

const SOURCE = '/assets/tiger.svg';
const nativeImage = ref(null);
const canvgImage = ref(null);

const stageConfig = {
  width: window.innerWidth,
  height: window.innerHeight
};

onMounted(() => {
  // Load native SVG
  const image = new window.Image();
  image.src = SOURCE;
  image.onload = () => {
    nativeImage.value = image;
  };

  // Load canvg library and render SVG
  const script = document.createElement('script');
  script.src = 'https://cdn.jsdelivr.net/npm/canvg/dist/browser/canvg.min.js';
  script.onload = () => {
    const canvas = document.createElement('canvas');
    canvg(canvas, SOURCE, {
      renderCallback: function () {
        canvgImage.value = canvas;
      },
    });
  };
  document.head.appendChild(script);

  return () => {
    script.remove();
  };
});
</script>

Open Sandbox

Instructions: The demo shows two SVG images rendered in different ways:

1. Left image: Native SVG rendering using Konva.Image
2. Right image: SVG rendered using canvg library