ISSUE-428: Definition of identical glyph

Definition of identical glyph

Raised by:
Glenn Adams
Opened on:
The definition of identical glyph use in section 9.5 is not adequate in the general case in which glyph mapping process is context sensitive. For example 'f' and 'i' may map to a ligature glyph for font F0 but to distinct glyphs for font F1. Similarly, for Arabic text and other complex scripts, the glyph mapping process is based on the font's GSUB tables and the set of active features and language bindings.
Related Actions Items:
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Related emails:
  1. {minutes} TTWG Meeting 2015-10-29 (from on 2015-10-29)
  2. {agenda} TTWG Meeting 2015-10-01 (from on 2015-10-01)
  3. {agenda} TTWG Meeting 2015-09-24 (from on 2015-09-23)
  4. Update re: outstanding IMSC1 issues (from on 2015-09-21)
  5. ISSUE-428: Definition of glyp [TTML IMSC 1.0] (from on 2015-09-21)

Related notes:

Ok. Nevertheless, would you expect the definition of identical glyph to hold 1%, 10% or 90% of the time?

Pierre-Anthony Lemieux, 21 Sep 2015, 21:05:32

It depends on the script in use. For Arabic script usage, perhaps 1%; for Indic script usage, perhaps 20%, for Roman script usage, perhaps 80-95%.

Glenn Adams, 24 Sep 2015, 15:13:57

Addressed at

Pierre-Anthony Lemieux, 31 Oct 2015, 19:03:45

Moved to

Nigel Megitt, 5 Jan 2016, 16:13:42

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