<switch>

Hello,

I'm wondering what good is the <switch> element if it doesn't seem to read  
the requiredFeatures attribute from unknown elements.

Additionally it doesn't fully disable processing of the non-chosen  
subtrees, as illustrated by the audio/video example below.

Questions:
* What should happen in the switch below?
* Should the audio from the video be heard?
* Should the requiredFeatures attributes be used by the switch even though  
these elements
   are unknown? Or is requiredFeatures only possible on svg elements that  
the UA knows about?
* Given the current state of implementations <switch> is very close to  
useless, how do we want to proceed wrt this for SVG2?

Example:

<svg xmlns='http://www.w3.org/2000/svg'  
xmlns:xlink='http://www.w3.org/1999/xlink' viewBox="0 0 400 400"  
id="svgroot">
 <text x="200" y="40" text-anchor="middle" font-size="9">You should see a  
video in the rectangle below if your browser supports
 <tspan x="200" dy="1.5em">foreignObject, HTML5 video and Ogg Theora  
(maybe).</tspan></text>
 <rect x="100" y="100" width="200" height="200" stroke-width="4"  
stroke="black" fill="none"/>
 <switch>
  <myCustomFooElement xmlns="http://example.com/foobarML" width="400"  
height="400" fill="red" requiredFeatures="bar"/>
  <aNewSvg5Element width="400" height="400" fill="red"  
requiredFeatures="SVG5featurestring"/>
  <foreignObject id="fo" x="100" y="100" width="200" height="200">
   <div xmlns="http://www.w3.org/1999/xhtml">
    <video width="200" height="200" autoplay="autoplay"  
controls="controls">
     <source src="example.ogv" type='video/ogg; codecs="theora, vorbis"'/>
    </video>
   </div>
  </foreignObject>
 </switch>
</svg>


-- 
Erik Dahlstrom, Core Technology Developer, Opera Software
Co-Chair, W3C SVG Working Group
Personal blog: http://my.opera.com/macdev_ed

Received on Thursday, 23 June 2011 12:01:36 UTC