W3C

- DRAFT -

WebFonts Working Group Teleconference

09 Jun 2015

See also: IRC log

Attendees

Present
Vlad, kuettel, RSheeter, sergey, ChrisL, Khaled
Regrets
Chair
vlad
Scribe
ChrisL

Contents


<trackbot> Date: 09 June 2015

<scribe> scribenick: ChrisL

predefined tables

Vlad: we have more tables than bits. do we swap out a less used one? or use a custom table?
... we need to add meta
... we have OT tables, all known, then AAT which are somewaht used, then odd stuff

ChrisL: the graphite tables are also there

kuettel: we have seen fonts with those tables

ChrisL: (explains Graphite)

RSheeter: easiest is to leave it alone and use 4 bytes

Vlad: we excluded vendor-specific tables used in production but not deployment

kuettel: when we did data gathering we only listed tables we actually saw

Vlad: ok so known table flags are full so any other table will use arbitrary tag flag plus actual tag, which is 4 bytes. no impact on functionality

sergeym: we know we use it a lot and apple does too in their system fonts. no data on frequency of use
... its okay

kuettel (shows list of observed table frequencies)

scribe: (looks for link)

s/fat fingers/agile, nimble fingers/

<kuettel> Here is the "Known Table Tags Proposal" thread from earlier

<kuettel> http://lists.w3.org/Archives/Public/public-webfonts-wg/2014Apr/0010.html

<kuettel> And here is the direct link to the spreadsheet with the underlying proposal data

<kuettel> https://docs.google.com/spreadsheets/d/111MT0l7LOVqotAnMXD4PMOm36jTPSznUigJPfxUYY_0/edit#gid=0

sergeym: meta is currently being defined

Vlad: next SC29 is in 2 weeks, could add to ammendment

sergeym: someone from Si Daniel's team is working on it

Vlad: (discussion of who on the team is doing it)
... could you ask who is doing the proposal? end of this week is the deadline

sergeym: we can send a mail to the list about it

Vlad: just need a draft spec language, and no objections

kuettel: in https://docs.google.com/spreadsheets/d/111MT0l7LOVqotAnMXD4PMOm36jTPSznUigJPfxUYY_0/edit#gid=0 the grey ones wwre allocated early, the green ones are the new OT tables
... color font ones from v.3
... after that, AAT and Graphite which we did find in use
... color font ones expected to be in use later
... so changes would affect fonts in the wild

Vlad: cvt is widely used

RSheeter: should not reallocate ones in the OT spec

kuettel: so everything allocated is used

resolved: leave known tables bitfield as it is

sergeym: ok

Vlad: even glyf table could be defined both ways, not forbidden. two parallel mechanisms to identify tables. no prefferential treatment

cts plans

Vlad: aim is to have no undefined items at end of meeting

https://www.w3.org/Fonts/WG/wiki/TestPlan20-AuthoringTool

Vlad: get rid of the untestables and the no-longer a requirement ones

http://dev.w3.org/webfonts/WOFF2/spec/#conform-mustNotDuplicateTables

Vlad: it says physical tables, so if shared its in a collection directory, but physical table must only be presented once

sergeym: need to check our tools do the right thing on all shared tables. if not shared on the input font, do we want to force the woff2 encoder to fail the check
... if it was shared in input font, it will be shared in woff
... meaning smae data
... but then if there is the same data, that could have been shared

RSheeter: don't want to do that

ChrisL: no, don't check for that

Vlad: each font can have it s own name table, but its not the tag but the offset that defines

ChrisL: don't want the wording to suggest a requirement for identity/duplicate table checking

(general agreement)

RSheeter: physical tables is a poor term

sergeym: if original font shared it, woff2 should share it

RSheeter: should not end up with more table offsets than you started with

Vlad: physical data must not be duplicated, is the intent
... clear this up by removing the mention of input font

ChrisL: works for me

kuettel: this is the only mention of physical table, which is undefined

RSheeter: if tables in input have same offset, corresponding entries in the woff should point to the same index

(discussion of bizarre cases with unused duplicate tables that nothing points to)

(live spec editing)

<RSheeter> If two tables have the same offset in the input font, the corresponding indices in the CollectionFontEntry in the woff2 file MUST be the same.

(discussion on whether the validator should also look at the input sfnt as well as the output woff, and custom vs. general purpose validators)

ChrisL: edited https://www.w3.org/Fonts/WG/wiki/TestPlan20-AuthoringTool#mustNotDuplicateTables

Vlad: make a dummy collection where all the entries are the same

RSheeter: if a table is physically duplicated and one copy unreferenced, it is a gap

(we need to check the gap requirement mentions collections)

<RSheeter> http://dev.w3.org/webfonts/WOFF2/spec/#conform-overlap-reject

(discussion on testing for extraneous data between tables in the compressed datastream)

Vlad: section 5 for compressed data format is the place for extraneous data mention

RSheeter: add a 5.5 specifiying restrictions on tables not having gaps

Vlad: or at the beginning section which applies to the whole datablock

kuettel: we need two, one FF and one AT

(live spec editing)

discussion of https://www.w3.org/Fonts/WG/wiki/TestPlan20-AuthoringTool#mustTransformMultipeGlyfLoca

(editing https://www.w3.org/Fonts/WG/wiki/TestPlan20-AuthoringTool#mustVerifyGlyfLocaShared )

(split into two tests)

https://www.w3.org/Fonts/WG/wiki/TestPlan20-AuthoringTool#mustRejectSingleGlyfLocaShared seems okay

(or maybe not)

sergey we are discussing https://www.w3.org/Fonts/WG/wiki/TestPlan20-AuthoringTool#mustRejectSingleGlyfLocaShared

(we split into two tests)

discussing http://dev.w3.org/webfonts/WOFF2/spec/#conform-mustRecordCollectionEntryIndex

https://www.w3.org/Fonts/WG/wiki/TestPlan20-AuthoringTool#mustRecordCollectionEntryIndex

RSheeter: in a number of places in the spec we need to explicit about the array suffix
... such as starting at zero

<RSheeter> starting at zero is specifically for http://dev.w3.org/webfonts/WOFF2/spec/#conform-mustRecordCollectionEntryIndex (never explicitly said it started at 0)

<RSheeter> Array suffixes would be nice (at least for me) in http://dev.w3.org/webfonts/WOFF2/spec/#glyf_table_format, which tends to just use the name xxxStream to indicate it repeats, eg "UInt32 nContourStream" vs "UInt32 nCountourStream[nContourStreamSize]"

must use transform on glyph and loca seems to be missing from spec

<RSheeter> <span class="conform at" id="mustUseTransform"> needs conform- prefix in id

necessity to reference RFC6919 averted http://tools.ietf.org/html/rfc6919#section-4

<scribe> done with autoring tool test plan

font format test plan

https://www.w3.org/Fonts/WG/wiki/TestPlan20-Format#magicNumber

RSheeter: OMG it's full of assertions

<RSheeter> *gasp*

<scribe> Meeting: WebFonts Working Group f2f, Woburn

sergeym, we are going through https://www.w3.org/Fonts/WG/wiki/TestPlan20-Format

<scribe> ACTION: RSheeter to make a new github repo with the compiled output from the test generator [recorded in http://www.w3.org/2015/06/09-webfonts-minutes.html#action01]

<trackbot> Created ACTION-180 - Make a new github repo with the compiled output from the test generator [on Roderick Sheeter - due 2015-06-16].

Khaled, we are going through https://www.w3.org/Fonts/WG/wiki/TestPlan20-Format

editing it live

(discussion on desirability of a test case where the font data and the metadata are erroneously all compressed in one brotli stream)

Khaled: its not impossible to make this

kuettel: would the extraneous tests not catch this

Khaled: such a font should be rejected by the validator

User Agent tests

https://www.w3.org/Fonts/WG/wiki/TestPlan20-UserAgent

(we discuss whether an unsorted table directory will cause a UA to not render a font, for excample because OTS rejects it)

table directory order and table order are changed from conformance requirements into a pointer to the OFF specification

ChrisL: we have conflated general decoder tests and user agent (browser) tests. We should split these into two conformance classes. Especially for TTC which can be inspected and are supported in software, but nit currently in browsers
... created https://www.w3.org/Fonts/WG/wiki/TestPlan20-Decoder

(discussion of extraneous-reject UA test)

(in particular that only inter-block extraneous data is covered in this section.)

https://www.w3.org/Fonts/WG/wiki/TestPlan20-UserAgent#mustRejectExtraData

(wondering what browsers do with a font with incorrect checksums)

<scribe> ACTION: vlad to add decoder category to woff2, and add to stylesheet [recorded in http://www.w3.org/2015/06/09-webfonts-minutes.html#action02]

<trackbot> Created ACTION-181 - Add decoder category to woff2, and add to stylesheet [on Vladimir Levantovsky - due 2015-06-16].

oh zakim, you lightweight

action-181?

<trackbot> action-181 -- Vladimir Levantovsky to Add decoder category to woff2, and add to stylesheet -- due 2015-06-16 -- OPEN

<trackbot> http://www.w3.org/Fonts/WG/track/actions/181

I edited conform.css to add a fourth class, dc for decoder

action items

close action-177

<trackbot> Closed action-177.

action-177?

<trackbot> action-177 -- Jonathan Kew to Propose two-bit per table version number -- due 2015-06-03 -- CLOSED

<trackbot> http://www.w3.org/Fonts/WG/track/actions/177

http://www.w3.org/Fonts/WG/track/actions/open

action-171?

<trackbot> action-171 -- Vladimir Levantovsky to Review conformance reqs to ensure they can actually be implemented -- due 2015-06-11 -- OPEN

<trackbot> http://www.w3.org/Fonts/WG/track/actions/171

close action-171

<trackbot> Closed action-171.

action-818?

<trackbot> Sorry, but action-818 does not exist.

action-181?

<trackbot> action-181 -- Vladimir Levantovsky to Add decoder category to woff2, and add to stylesheet -- due 2015-06-16 -- OPEN

<trackbot> http://www.w3.org/Fonts/WG/track/actions/181

partly done (stylesheet part)

<scribe> ACTION: vlad to check with barbara re atypi-colocated meeting [recorded in http://www.w3.org/2015/06/09-webfonts-minutes.html#action03]

<trackbot> Created ACTION-182 - Check with barbara re atypi-colocated meeting [on Vladimir Levantovsky - due 2015-06-16].

(adjourned, agenda finished)

Summary of Action Items

[NEW] ACTION: RSheeter to make a new github repo with the compiled output from the test generator [recorded in http://www.w3.org/2015/06/09-webfonts-minutes.html#action01]
[NEW] ACTION: vlad to add decoder category to woff2, and add to stylesheet [recorded in http://www.w3.org/2015/06/09-webfonts-minutes.html#action02]
[NEW] ACTION: vlad to check with barbara re atypi-colocated meeting [recorded in http://www.w3.org/2015/06/09-webfonts-minutes.html#action03]
 
[End of minutes]

Minutes formatted by David Booth's scribe.perl version 1.140 (CVS log)
$Date: 2015/06/09 21:57:27 $

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This is scribe.perl Revision: 1.140  of Date: 2014-11-06 18:16:30  
Check for newer version at http://dev.w3.org/cvsweb/~checkout~/2002/scribe/

Guessing input format: RRSAgent_Text_Format (score 1.00)

Succeeded: s/vendore/vendor/
Succeeded: s/apople/apple/
FAILED: s/fat fingers/agile, nimble fingers/
Found ScribeNick: ChrisL
Inferring Scribes: ChrisL
Present: Vlad kuettel RSheeter sergey ChrisL Khaled
Found Date: 09 Jun 2015
Guessing minutes URL: http://www.w3.org/2015/06/09-webfonts-minutes.html
People with action items: rsheeter vlad

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