[ttml2] tts:rubyReserve length component semantics

palemieux has just created a new issue for https://github.com/w3c/ttml2:

== tts:rubyReserve length component semantics ==
The stated purpose of `tts:rubyReserve` is to space lines within a `p` as if ruby text annotations were present, regardless of the presence or absence of ruby text annotations.

The increase of spacing between lines in the presence of ruby text annotations is implementation dependent, and depends on the font size of the ruby text annotations.

The `length` component should therefore specify the font size of these hypothetical ruby text annotations, instead of specifying the absolute _amount by which the before or (and) after leading(s) of an affected line area are increased_. The absence of a `length` component should trigger the `tts:fontSize` special semantics (10.2.21.1 Special Semantics).

Please view or discuss this issue at https://github.com/w3c/ttml2/issues/779 using your GitHub account

Received on Saturday, 19 May 2018 06:04:28 UTC