[ttml2] Pull Request: Clarify use of terms altitude, depth, and line gap; add non-normative…

skynavga has just submitted a new pull request for https://github.com/w3c/ttml2:

== Clarify use of terms altitude, depth, and line gap; add non-normative… ==
… reference to open font format (#889).

Closes #889.

See https://github.com/w3c/ttml2/pull/890

Received on Friday, 13 July 2018 00:50:09 UTC