How to scale SVG image to fill browser window?

Miral picture Miral · Apr 13, 2011 · Viewed 76.4k times · Source

This seems like it ought to be easy, but I'm just not getting something.

I want to make an HTML page containing a single SVG image that automatically scales to fit the browser window, without any scrolling and while preserving its aspect ratio.

For example, at the moment I have a 1024x768 SVG image; if the browser viewport is 1980x1000 then I want the image to display at 1333x1000 (fill vertically, centred horizontally). If the browser was 800x1000 then I want it to display at 800x600 (fill horizontally, centred vertically).

Currently I have it defined like so:

<body style="height: 100%">
  <div id="content" style="width: 100%; height: 100%">
    <svg xmlns="http://www.w3.org/2000/svg" version="1.1"
         width="100%" height="100%"
         viewBox="0 0 1024 768"
         preserveAspectRatio="xMidYMid meet">
      ...
    </svg>
  </div>
</body>

However this is scaling up to the full width of the browser (for a wide but short window) and producing vertical scrolling, which isn't what I want.

What am I missing?

Answer

Phrogz picture Phrogz · Apr 13, 2011

How about:

html, body { margin:0; padding:0; overflow:hidden }
svg { position:fixed; top:0; bottom:0; left:0; right:0 }

Or:

html, body { margin:0; padding:0; overflow:hidden }
svg { position:fixed; top:0; left:0; height:100%; width:100% }

I have an example on my site using (roughly) this technique, albeit with 5% padding all around, and using position:absolute instead of position:fixed:
http://phrogz.net/svg/svg_in_xhtml5.xhtml

(Using position:fixed prevents a very edge-case scenario of linking to a sub-page anchor on the page, and overflow:hidden can ensure that no scroll bars ever appear (in case you have extra content.)