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Re: Responses to Tantek Çelik issues raised during third last call of UAAG 1.0

From: Tantek Celik <tantek@cs.stanford.edu>
Date: Tue, 10 Jul 2001 15:14:44 -0700
To: Jon Gunderson <jongund@uiuc.edu>
CC: w3c-wai-ua@w3.org
Message-ID: <1217289643-252601605@psdbay.com>
From: Jon Gunderson <jongund@uiuc.edu>
Cc: w3c-wai-ua@w3.org
Subject: Re: Responses to Tantek Çelik issues     raisedduring third  last
call of UAAG 1.0
Date: Mon, Jul 9, 2001, 2:43 PM

> Tantek,
>
> The main difference between what I think you want and what the group can
> provide is you would like something based upon usability of the rendered
> fonts, especially in the Macintosh environment.

Not at all - nothing I said is specific to the Macintosh environment.

> We tried that approach and
> invited font experts to help in defining minimal usable sizes based on
> pixels or something else.  Our main obstacles in achieving a minimum limit
> based on a minimal size in pixels were internationalization and hardware
> issues.

I am not asking for a minimal size which would be guaranteed to work across
languages and hardware.

I am merely asking for the flexibility for user agents to disallow sizes
which are known to be completely unusable to anyone.  The current text does
not seem to have this flexibility, and thus encourages bad design
(permitting users to choose useless values).

> The groups only other choice was to say whatever the operating
> environment supported.  This is approach is based on system capability and
> not on usability as we had wished.  It is assumed by using this requirement
> that the system would provide a set of usable font sizes.

The assumption is not only false, but ill conceived.

Operating systems provide the ability to render fonts as small as 1 pixel
tall (which is meaningless for legibility purposes, but provides a way to
draw seemingly random broken lines), simply because at the system
application program interface (API) level, it is easiest to provide maximum
flexibility, with the intent that _applications_ which are built on top of
the operating system will be written to provide usable text sizes in their
user interface, and may user other text sizes for other purposes (perhaps
for showing previews which are not meant to have legible text).

> The limitation
> of this approach, as you have pointed out, is that it may require user
> agents to render content that is in a font size that is not very usable to
> anyone.  But that is the best the working group can currently provide.  We
> are open to suggestions to improve this (or any part) of UAAG specifications.
>
> So the group resolved not to specify a minimum size in pixels in either the
> guidelines or techniques document.
> This problem is part of the statement that was included in the 22 June draft:
>
> "This checkpoint does not include a "lower bound" (above which text sizes
> would be required) because of how users' needs may vary across writing
> systems and hardware."

Strictly speaking, I agree with these statements.

In fact I would rather not see a minimum size specified in the guidelines or
techniques document as a _requirement_.

However, under the premise that the guidelines and techniques should
encourage (not discourage) more accessible and usable user interfaces, some
wording should be added which permits the user agent to set a lower bound on
its font size preferences.  What that lower bound is, probably should not be
specified in the techniques or guidelines document, for the reasons you
state.

> Questions:
> 1. What capabilities does the Mac OS environment provide to developers for
> specifying the size of text rendered on the graphical display?

1 pixel to 255 pixels.

> 2. What system resources are available to allow the user to choose the font
> sizes available for a particular font family?

There are no system resources which allow the user to specifically choose
the font sizes available for a particular font family for all font families.

What is available is the system "Appearance" control panel, which permits
the user to choose:
 - which font family is used for the "Large System Font"
   . note: only among a subset of the fonts on the system
   . no size preference is given.
 - which font family is used for the "Small System Font"
   . note: only among an even smaller subset of the fonts on the system,
           on my machine, "Geneva" was the only choice.
   . no size preference is given.
 - which font family is used for the "Views Font"
   . a size preference is given with both a menu (9,10,12,14,18,24),
     and a text entry box which shows the currently chosen size.
       If you try to enter a size smaller than 9, when you close the
     control panel, the size is rejected, and reset to its previous value.


The idea of disallowing sizes smaller than 9 pixels is not a new one.

Note that this is _very_ different than requiring that sizes 9 pixels and
larger be available, which I would agree, is a problematic statement.

Even requiring the disallowing of sizes smaller than 9 pixels may be
considered problematic.

To be very clear - I am not asking for either of these requirements.

I am asking for wording which provides the flexibility to the user agent to
disallow sizes that are smaller than what the user agent deems as legible
(this takes care of the international and hardware issues, because
presumably the user agent has enough information to make those decisions
correctly).

Thanks,

Tantek



> At 12:56 PM 7/9/2001 -0700, you wrote:
>>Thanks Jon.
>>
>>By the way, here is a reference to a document by Todd Fahrner which
>>discusses (among other things) the 9 pixel minimum for legible text.
>>
>>  http://style.cleverchimp.com/font_size_intervals/altintervals.html
>>
>>Tantek
>>
>>----------
>> >From: Jon Gunderson <jongund@uiuc.edu>
>> >To: "Tantek Celik" <tantek@CS.Stanford.EDU>, "ian b. jacobs" <ij@w3.org>
>> >Cc: w3c-wai-ua@w3.org
>> >Subject: Re: Responses to Tantek Çelik issues   raisedduring third  last
>> call
>>of UAAG 1.0
>> >Date: Mon, Jul 9, 2001, 12:15 PM
>> >
>>
>> > Tantek,
>> > The checkpoint currently does not set a box size.  Your argument for 9
>> > pixels seems satisfactory to me.  I know we considered having this type of
>> > information in the note.  I am not sure why we did not include it.  Ian do
>> > remember why we didn't include this information in the note?
>> >
>> > Jon
>> >
>> >
>> >
>> > At 12:04 PM 7/9/2001 -0700, Tantek Celik wrote:
>> >>From: Jon Gunderson <jongund@uiuc.edu>
>> >>Subject: Re: Responses to Tantek Çelik issues raisedduring third last call
>> >>of UAAG 1.0
>> >>Date: Mon, Jul 9, 2001, 7:44 AM
>> >>
>> >> > But there is no need to allow the user in this case [8x8 pixels] to
>> >> decrease
>> >> > the font size.
>> >> >
>> >> > Since there is no accessibility requirement for smaller sizes, no
>> priority
>> >> > is associated with adding this capability to a browser.
>> >>
>> >>Good.  I will take this to mean that it is ok for the font size preference
>> >>in a UA to have a lower limit of 8 pixels.
>> >>
>> >>As an example, currently in IE5/Mac we have both the ability to set the
>> >>default medium font size (in pixels) and the resolution of the display
>> >>(since the Macintosh provides no capability in the operating system for
>> >>doing so).  IE5/Mac also provides the ability to instantly "zoom" the size
>> >>of all text on any page through its easily accessible "Text Zoom" menu.
>> >>
>> >>Our font size preference is a menu of typical/popular options
>> >>(12,14,16,18,24) and an "Other..." option which allows the user to enter
>> >>their preferred default medium font size.  If the user enters a size less
>> >>than 9, the value is set to 9.  This was based upon input from Todd
>> Fahrner,
>> >>a screen font/typography expert who noted that 9 pixels is really the
>> >>practical minimum for readable text (8 pixels being too small).
>> >>
>> >> >From my understanding of this discussion, IE5/Mac would NOT be
>> considered to
>> >>be compliant with this checkpoint (despite having perhaps the most
>> >>comprehensive user control over font size and screen resolution of
>> available
>> >>visual web browsers as noted in numerous reviews).
>> >>
>> >>Also from my understanding of this discussion, if we changed this lower
>> >>bound to 8, then we would be compliant with this checkpoint.
>> >>
>> >>I'd like to ask the (perhaps rhetorical) question, who would be helped by
>> >>this change?
>> >>
>> >>Either way, I'd like to suggest that a parenthetical comment be added
>> to the
>> >>checkpoint description summarizing what you said about western characters
>> >>and 8 pixels (or my suggestion: 9 pixels) being the effective limit of
>> >>readability.
>> >>
>> >>Thanks,
>> >>
>> >>Tantek
>> >>
>> >>----------
>> >> >From: Jon Gunderson <jongund@uiuc.edu>
>> >> >To: "Tantek Celik" <tantek@CS.Stanford.EDU>, "Ian B. Jacobs" <ij@w3.org>
>> >> >Cc: w3c-wai-ua@w3.org
>> >> >Subject: Re: Responses to Tantek Çelik issues raisedduring third  last
>> >> call of
>> >>UAAG 1.0
>> >> >Date: Mon, Jul 9, 2001, 7:44 AM
>> >> >
>> >>
>> >> > It was difficult for the working group to come up with a required
>> minimum
>> >> > size for many reasons, including internationalization issues.  It can be
>> >> > assumed for western characters that are visually rendered in a box less
>> >> > than 8x8 pixels it would be difficult or impossible for most people to
>> >> > read.  If an author specified a font size that resulted in a graphical
>> >> > rendering in a box less that 8x8 pixels box accessibility
>> requirement would
>> >> > be to increase the text size (probably needed for everyone) to one
>> that is
>> >> > readable.  But there is no need to allow the user in this case to
>> decrease
>> >> > the font size.
>> >> >
>> >> > Since there is no accessibility requirement for smaller sizes, no
>> priority
>> >> > is associated with adding this capability to a browser.
>> >> >
>> >> > Jon
>> >> >
>> >> >
>> >> > At 02:13 AM 7/9/2001 -0700, Tantek Celik wrote:
>> >> >> > ------------------------------------------------------------------
>> >> >> > Issue 512: Checkpoint 4.1: Range of text sizes
>> >> >> > http://server.rehab.uiuc.edu/ua-issues/issues-linear-lc3.html#512
>> >> >> > ------------------------------------------------------------------
>> >> >> >
>> >> >> > Issue summary: Is it a P1 requirement to allow configuration of very
>> >> >> > small text sizes?
>> >> >> >
>> >> >> > Resolution:
>> >> >> >
>> >> >> >  - The UAWG agrees that the intent of this checkpoint is to allow the
>> >> >> >  user to choose large, not small, text sizes.
>> >> >> >
>> >> >> >  - However, after consultation with other Working Groups, the UAWG
>> >> >> >  concluded that, in light of internationalization issues (and
>> others),
>> >> >> >  the WG could not come up with a lower bound on the requirement
>> >> >> >  with any confidence.
>> >> >> >
>> >> >> >  - Therefore, the WG resolved to leave the checkpoint as is with a
>> >> >> >    note in the Techniques document:
>> >> >> >
>> >> >> >    <BLOCKQUOTE>
>> >> >> >     The primary intention of this checkpoint is to allow users with
>> >> >> >     low vision to increase the size of text. Full configurability
>> >> >> >     includes the choice of (very) small text sizes that may be
>> >> >> >     available, though this is not considered by the User Agent
>> >> >> >     Accessibility Guidelines Working Group to be part of the priority
>> >> >> >     1 requirement.  This checkpoint does not include a "lower bound"
>> >> >> >     (above which text sizes would be required) because of how users'
>> >> >> >     needs may vary across writing systems and hardware.
>> >> >> >    </BLOCKQUOTE>
>> >> >>
>> >> >>I would like to point out that the reason I raised this issue is
>> that some
>> >> >>very small text sizes are illegible (e.g. anything less than 9px
>> >> >>unsmoothed), and therefore, it may be preferable for a UA to set a
>> "lower
>> >> >>bound" for the purposes of avoiding "unusable" configurations.
>> >> >>
>> >> >>Is it a P2 (or P3) requirement to permit users to configure the size of
>> >> text
>> >> >>to such illegible sizes?
>> >> >>
>> >> >>Thanks,
>> >> >
>> >> > Jon Gunderson, Ph.D., ATP
>> >> > Coordinator of Assistive Communication and Information Technology
>> >> > Division of Rehabilitation - Education Services
>> >> > MC-574
>> >> > College of Applied Life Studies
>> >> > University of Illinois at Urbana/Champaign
>> >> > 1207 S. Oak Street, Champaign, IL  61820
>> >> >
>> >> > Voice: (217) 244-5870
>> >> > Fax: (217) 333-0248
>> >> >
>> >> > E-mail: jongund@uiuc.edu
>> >> >
>> >> > WWW: http://www.staff.uiuc.edu/~jongund
>> >> > WWW: http://www.w3.org/wai/ua
>> >> >
>> >> >
>> >
>> > Jon Gunderson, Ph.D., ATP
>> > Coordinator of Assistive Communication and Information Technology
>> > Division of Rehabilitation - Education Services
>> > MC-574
>> > College of Applied Life Studies
>> > University of Illinois at Urbana/Champaign
>> > 1207 S. Oak Street, Champaign, IL  61820
>> >
>> > Voice: (217) 244-5870
>> > Fax: (217) 333-0248
>> >
>> > E-mail: jongund@uiuc.edu
>> >
>> > WWW: http://www.staff.uiuc.edu/~jongund
>> > WWW: http://www.w3.org/wai/ua
>> >
>> >
>
> Jon Gunderson, Ph.D., ATP
> Coordinator of Assistive Communication and Information Technology
> Division of Rehabilitation - Education Services
> MC-574
> College of Applied Life Studies
> University of Illinois at Urbana/Champaign
> 1207 S. Oak Street, Champaign, IL  61820
>
> Voice: (217) 244-5870
> Fax: (217) 333-0248
>
> E-mail: jongund@uiuc.edu
>
> WWW: http://www.staff.uiuc.edu/~jongund
> WWW: http://www.w3.org/wai/ua
>
> 
Received on Wednesday, 11 July 2001 02:28:21 GMT

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