Drawing an SVG file on a HTML5 canvas

Question

EDIT: Dec 2019

The Path2D() constructor is supported by all major browsers now, "allowing path objects to be declared on 2D canvas surfaces".

---

EDIT: Nov 2014

You can now use ctx.drawImage to draw HTMLImageElements that have a .svg source in some but not all browsers (75% coverage: Chrome, IE11, and Safari work, Firefox works with some bugs, but nightly has fixed them).

var img = new Image();
img.onload = function() {
    ctx.drawImage(img, 0, 0);
}
img.src = "http://upload.wikimedia.org/wikipedia/commons/d/d2/Svg_example_square.svg";

Live example here. You should see a green square in the canvas. The second green square on the page is the same <svg> element inserted into the DOM for reference.

You can also use the new Path2D objects to draw SVG (string) paths. In other words, you can write:

var path = new Path2D('M 100,100 h 50 v 50 h 50');
ctx.stroke(path);

Live example of that here.

---

Original 2010 answer:

There's nothing native that allows you to natively use SVG paths in canvas. You must convert yourself or use a library to do it for you.

I'd suggest looking in to canvg: (check homepage & demos)

canvg takes the URL to an SVG file, or the text of the SVG file, parses it in JavaScript and renders the result on Canvas.

Further to @Matyas answer: if the svg's image is also in base64, it will be drawn to the output.

Demo:

var svg = document.querySelector('svg');
var img = document.querySelector('img');
var canvas = document.querySelector('canvas');

// get svg data
var xml = new XMLSerializer().serializeToString(svg);

// make it base64
var svg64 = btoa(xml);
var b64Start = 'data:image/svg+xml;base64,';

// prepend a "header"
var image64 = b64Start + svg64;

// set it as the source of the img element
img.onload = function() {
    // draw the image onto the canvas
    canvas.getContext('2d').drawImage(img, 0, 0);
}
img.src = image64;

svg, img, canvas {
  display: block;
}

SVG
<svg height="40" width="40">
  <rect width="40" height="40" style="fill:rgb(255,0,255);" />
  <image xlink:href="data:image/png;base64,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" height="20px" width="20px" x="10" y="10"></image></svg><br/>

IMAGE 
<img/><br/>
   
CANVAS 
<canvas></canvas><br/>

You can easily draw simple svgs onto a canvas by:

1. Assigning the source of the svg to an image in base64 format
2. Drawing the image onto a canvas

Note: The only drawback of the method is that it cannot draw images embedded in the svg. (see demo)

Demonstration:

(Note that the embedded image is only visible in the svg)

var svg = document.querySelector('svg');
var img = document.querySelector('img');
var canvas = document.querySelector('canvas');

// get svg data
var xml = new XMLSerializer().serializeToString(svg);

// make it base64
var svg64 = btoa(xml);
var b64Start = 'data:image/svg+xml;base64,';

// prepend a "header"
var image64 = b64Start + svg64;

// set it as the source of the img element
img.src = image64;

// draw the image onto the canvas
canvas.getContext('2d').drawImage(img, 0, 0);

svg, img, canvas {
  display: block;
}

SVG

<svg height="40">
  <rect width="40" height="40" style="fill:rgb(255,0,255);" />
  <image xlink:href="https://en.gravatar.com/userimage/16084558/1a38852cf33713b48da096c8dc72c338.png?size=20" height="20px" width="20px" x="10" y="10"></image>
</svg>
<hr/><br/>

IMAGE
<img/>
<hr/><br/>
   
CANVAS
<canvas></canvas>
<hr/><br/>

Mozilla has a simple way for drawing SVG on canvas called "Drawing DOM objects into a canvas"

As Simon says above, using drawImage shouldn't work. But, using the canvg library and:

var c = document.getElementById('canvas');
var ctx = c.getContext('2d');
ctx.drawSvg(SVG_XML_OR_PATH_TO_SVG, dx, dy, dw, dh);

This comes from the link Simon provides above, which has a number of other suggestions and points out that you want to either link to, or download canvg.js and rgbcolor.js. These allow you to manipulate and load an SVG, either via URL or using inline SVG code between svg tags, within JavaScript functions.