semantics of unbound region attribute.

Another issue that has concerned me lately is what it means when the region attribute is unspecified. According to the spec, this simply means the sub-tree does not show up in the rendering, Which is fine and simple to understand and implement; however I'm wondering if it should perhaps instead have the special meaning of 'any region'.

For example:
    <div region="r1">
      <p tts:color="red" begin="0s" end="10s">This text must be red.</p>
      <div region="r2">
          <p tts:color="blue" begin="0s" end="10s">This text must be blue.</p>

In this case, clearly the intent is that div 1 shows up in r1 and div 2 shows up in r2, however without specifying <body region="r1 r2">  this won't happen. In complex scenarios I can imagine the amount of region attributes getting quite tedious.

Also, if as we have discussed, we are going to allow the idea of an anonymous default region, which I think most of the test suite now relies on, we will need some sort of rule like this anyway in order to get content to be targeted at that anonymous region.

We could still allow that an explicit declaration of no region <body region=""> means that it will show up in no region at all to retain the current semantics.

Sean Hayes
Media Accessibility Strategist
Accessibility Business Unit

Office:  +44 118 909 5867,
Mobile: +44 7875 091385

Received on Wednesday, 10 December 2008 17:25:14 UTC