- From: Sean Hayes <Sean.Hayes@microsoft.com>
- Date: Wed, 10 Dec 2008 16:25:50 +0000
- To: "public-tt@w3.org" <public-tt@w3.org>
- Message-ID: <90EEC9D914694641A8358AA190DACB3D2FCEA6245A@EA-EXMSG-C334.europe.corp.microsoft.>
All of the test suite examples look like the following:
...
</head>
<body>
<div>
<p tts:color="red" begin="0s" end="10s">This text must be red.</p>
</div>
</body>
</tt>
However the semantics here are in fact that nothing gets displayed:
Spec:
If no timeContainer attribute is specified, then a body element must be interpreted as having sequential time containment semantics
And (constraints on SMIL semantics)
The implicit duration of body, div, p, and span (whether anonyous or not) is defined as follows: if the element's parent time container is a parallel time container, then the implicit duration is equivalent to the indefinite duration value as defined by [SMIL 2.1]; if the element's parent time container is a sequential time container, then the implicit duration is equivalent to zero.
Thus since the div is in a sequential context, and neither dur nor end is specified, its active duration is 0.
Since we probably don't want this behaviour, I suggest we either change the default time container semantics of body as par, or fix all of the test suite cases where this occurs.
Sean Hayes
Media Accessibility Strategist
Accessibility Business Unit
Microsoft
Office: +44 118 909 5867,
Mobile: +44 7875 091385
Received on Wednesday, 10 December 2008 16:28:10 UTC