Re: WOFF 2.0: Known Table Tags Proposal

SGTM.  And again, I don't think this is worth any more of your (or the
working group's) time.


On Mon, Apr 14, 2014 at 3:54 PM, David Kuettel <kuettel@google.com> wrote:

> On Mon, Apr 14, 2014 at 6:37 AM, Levantovsky, Vladimir <
> Vladimir.Levantovsky@monotype.com> wrote:
>
>>  I agree, for WOFF 2.0 encoding we should compile a list of popular /
>> frequently used tables, and any one-of-a-kind table that is rarely seen can
>> simply be treated as an arbitrary tag. As far as table tags in general are
>> concerned, the SFNT /TrueType / OpenType common structures presume that all
>> original TrueType tags are spelled in lowercase letters, and all other tags
>> should be all caps only. The mix of caps / lowercase characters in the same
>> tag is not permitted.
>>
>
> Thank you Vlad, Behdad, John and Sergey.
>
> Exploring this ("popular / frequently used tables") further, would we be
> open to omitting the older unused Apple/TrueType tables?
>
> For example, with the corpus of fonts that I tested with, I did not find
> any fonts using the acnt, avar, bdat, bloc, bsln, cfar, fdsc, fmtx, fvar,
> gvar, hsty, lcar, opbd, prop, track or Zapf tables.  Rather, the few that
> were used include: feat, just, mort, motx.  Were we open to exploring this,
> we would likely want to check a larger collection of fonts to confirm of
> course.
>
> To summarize (and capture the most recent proposals), shall we add tags
> for the following known tables:
>
> [ See column B, with the additional tables highlighted in green ]
>
> https://docs.google.com/a/google.com/spreadsheets/d/111MT0l7LOVqotAnMXD4PMOm36jTPSznUigJPfxUYY_0/edit#gid=0
>
> (1) OpenType tables that were missed earlier: EBSC, JSTF, DSIG
> (2) Color font proposals: CBDT, CBLC, sbix, COLR, CPAL, "SVG "
> (3) Apple/TrueType tables (which are still used*): feat, just, mort, morx
> (4) Microsoft MATH table: MATH
> (5) SIL Graphite (non-standardized) tables: Silf, Glat, Gloc, Feat, Sill
>
> (*) Assumes we are open to dropping Apple/TrueType tables that are no
> longer used (see above).
>
>>
>>
>> Thank you,
>>
>> Vlad
>>
>>
>>
>>
>>
>> *From:* Behdad Esfahbod [mailto:behdad@google.com]
>> *Sent:* Friday, April 11, 2014 6:57 PM
>> *To:* David Kuettel
>> *Cc:* public-webfonts-wg@w3.org
>> *Subject:* Re: WOFF 2.0: Known Table Tags Proposal
>>
>>
>>
>> At the end of the day, this doesn't matter much, we are talking saving,
>> say, 20 bytes, for a rare font.  I think you should just fix a set and move
>> on.
>>
>>
>>
>> On Fri, Apr 11, 2014 at 3:51 PM, David Kuettel <kuettel@google.com>
>> wrote:
>>
>> On Fri, Apr 11, 2014 at 2:41 PM, Behdad Esfahbod <behdad@google.com>
>> wrote:
>>
>> Thanks David.  Your code may be buggy with tags that have space in them.
>>  It doesn't make sense that you didn't find any "cvt " or "CFF ".  Other
>> than that, I suggest dropping EPAR as well as anything that shouldn't be in
>> a final shipped product (VTT, etc).
>>
>>
>>
>> Great points Behdad, I should have elaborated in my earlier emails.
>>
>>
>>
>> The tool that I used was 'showttf' on Linux, which did segfault on some
>> of the files.  A better tool would have been fonttools, esp. due to the
>> worldclass support from you. :)
>>
>>
>>
>> The collection of fonts (while good sized) did not contain PostScript/CFF
>> fonts.  I need a bigger test set.
>>
>>
>>
>> Really, lets just keep this to the union of OpenType spec, Apple
>> TrueType, Graphite, and color fonts.
>>
>>
>>
>> Regarding the Apple TrueType font tables, given that so few are likely
>> still in use today, would it make since to whittle down the list a bit?  Or
>> perhaps again, my test collection was too limited.
>>
>>
>>
>> Cheers,
>>
>> behdad
>>
>>
>>
>> On Fri, Apr 11, 2014 at 2:05 PM, David Kuettel <kuettel@google.com>
>> wrote:
>>
>> To sanity check the initial list, I dumped the tables over a moderate
>> sized collection of fonts, and then color coded the entries in the
>> spreadsheet to reflect real-world usage (for this collection).
>>
>>
>>
>>
>> https://docs.google.com/a/google.com/spreadsheets/d/111MT0l7LOVqotAnMXD4PMOm36jTPSznUigJPfxUYY_0/edit#gid=0
>>
>>
>>
>> The color coding ranges from dark green, to represent the most commonly
>> used tables (e.g. name, glyph), to light green, to represent the least
>> commonly used tables (e.g. JSTF, mort, Silf, etc).
>>
>>
>>
>> The red entries represent tables that were not found with this collection
>> (e.g. acnt, fmtx, TeX, etc).
>>
>>
>>
>> The white (no color) entries represent tables that likely would have been
>> present in a larger collection (e.g. CFF, cvt, sbix, COLR, etc).
>>
>>
>>
>>
>>
>> Interestingly enough, the more tables that I look for, the more I find.
>>  For example, FontLab's Glossary page documents a ton of optional font
>> tables: http://blog.fontlab.com/info/  e.g. TSI1..TSIV and many more.
>>
>>
>>
>> Thus, I am wondering if we should revisit the goal of trying to capture
>> all known / used table tags.  Perhaps, esp. in light of this data, it would
>> be better to just capture the most commonly used tables today, while
>> ensuring that the rarely used ones would simply be passed through the WOFF
>> 2.0 encode/decode process...
>>
>>
>>
>> Thoughts?
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
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