[imsc] Ambiguous `#position` constraints. (#486)

skynavga has just created a new issue for https://github.com/w3c/imsc:

== Ambiguous `#position` constraints. ==
The following text at [1] is ambiguous:

>The tts:position attribute SHALL NOT be present in a Document Instance if any tts:origin attribute is also present.

In particular, it doesn't indicate the scope for evaluating the presence of `tts:origin`. Is it the entire document instance or the same `region` element on which `tts:position` is specified?

[1] https://www.w3.org/TR/ttml-imsc1.1/#text-position

Please view or discuss this issue at https://github.com/w3c/imsc/issues/486 using your GitHub account

Received on Saturday, 10 August 2019 09:36:00 UTC