[MPEG-OTSPEC] WD for AMD 2 and COLR v1 enhancements

[Vladimir Levantovsky]

Hello all,

Many thanks to Peter, Rod, Dominik, and many other people who have
contributed their review comments to the development and improvements of
the proposed text for COLR v1 amendment.

Since the deadlines for registration and upload of input contributions is
coming up soon, I would like to propose the following plan of actions:
- use the updated COLR v1 text from the public GitHub repo
https://github.com/googlefonts/colr-gradients-spec#annex-a-proposed-changes-to-isoiec-14496-22
as the basis for the updated proposal;
- extend the current draft amendment with three additional amended parts
proposed as part of MPEGGroup/OpenFontFormat
<https://github.com/MPEGGroup/OpenFontFormat/issues>discussions (issues
36-38);
- submit the AHG Recommendation to consider the proposed changes be used as
a replacement to the current content of the Working Draft ISO/IEC
14496-22/AMD2.

Please submit your additional comments and proposed changes (if any) no
later than the end of day on December 30. In absence of additional
comments, and if no objections will have been raised by Dec. 30 - I will
consider the current text of the proposal, along with the additional
changes, to be approved by AHG consensus.

Thank you again for your contributions!
Vladimir


On Tue, Dec 22, 2020 at 10:00 PM Peter Constable <pgcon6 at msn.com> wrote:

> In the past few weeks, I’ve been working with Rod Sheeter and Dominik
> Röttsches at Google to draft updates for the working draft related to COLR
> version 1. This fills out details for the new formats added in COLR version
> 1 as well as integrating with the existing text for COLR version 0 (which
> doesn’t go away).
>
>
>
> The proposed content for OFF Amendment 2 is available here:
>
>
> https://github.com/googlefonts/colr-gradients-spec#annex-a-proposed-changes-to-isoiec-14496-22
>
>
>
> When the COLR v1 enhancements were proposed here back in September, the
> proposal doc had specific details on the structure formats, but not much
> explanation of the semantics — how the formats represent different graphic
> concepts and are to be processed. Much of the additional content in this
> draft is conceptual explanation of the graphic operations that are
> supported and how the structures are used to represent those, with several
> figures to illustrate. The intent was not obvious before, but should be
> clear now with these additions.
>
>
>
> There have also been some further design enhancements in the proposed
> draft: additional paint table formats for translate, rotate and skew
> transformations—the separate formats are more compact than the matrix
> format if only the specific transform is needed, and the rotate/skew
> formats specify rotation angles in degrees, which is much better when
> varying a rotation angle in a variable font than varying the matrix
> elements.
>
>
>
> There are a few open issues (“TBD: …” in that doc), but these are limited
> in scope and shouldn’t hinder revision of the working draft considered by
> SC29 at the January meeting.
>
>
>
> AHG members are invited to review and comment. I’d suggest that general
> comments not requiring specific action could be sent to this list, but for
> suggested improvement, it would be better to track these in GitHub
> issues—either in the GitHub repo above or in the MPEG/OFF repo:
>
>
>
> Issues · MPEGGroup/OpenFontFormat (github.com)
> <https://github.com/MPEGGroup/OpenFontFormat/issues>
>
>
>
>
>
> Re COLR v1 and OpenType: I’ve been preparing a parallel draft for the next
> OT version. That’s in MSFT’s typography repo, which is still a private
> repo. The content will differ from the OFF content only in minor,
> non-technical wording details.
>
>
>
>
>
>
>
> Peter Constable
> _______________________________________________
> mpeg-otspec mailing list
> mpeg-otspec at lists.aau.at
> https://lists.aau.at/mailman/listinfo/mpeg-otspec
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.aau.at/pipermail/mpeg-otspec/attachments/20201227/503b79c3/attachment.html>