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Thread: text only zoom

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Number of posts in this thread: 6 (In chronological order)

From: Joseph Sherman
Date: Fri, Jun 17 2016 8:45AM
Subject: text only zoom
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Following up on this: Given that FireFox is the only browser that allows for Text-only zoom; that responsive design eliminates horizontal scrolling; and almost none of the sites I visited worked perfectly with 200% text-only zoom- Should text-only zoom still be a (high) concern?


Joseph

-----Original Message-----
From: WebAIM-Forum [mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Guy Hickling
Sent: Thursday, June 16, 2016 7:50 PM
To: = EMAIL ADDRESS REMOVED =
Subject: Re: [WebAIM] complex form questions

Joseph,

For your second question, normally, setting both height and width of a text container in px units is a definite no-no for accessibility.
Text-only zoom, in any browser that allows it, for instance Firefox, is a very useful tool for people with poor sight because they can increase the text size but still keep the whole page within the window without having to scroll horizontally to read long lines of text, or other content. (IE11 no longer allows text-only zoom, IE10 did.) The WCAG specifies allowing upto 200% without corrupting content, but some users will go as high as their browser will allow.

Unfortunately what happens is that, as the user increases the text size, the container can only remain the same size if it's dimensions are in pixels. This means text overflows outside it's container, overwriting whatever's to the right or below it. This is seen regularly on all too many sites, where one lot of text overwriting another lot makes both texts unreadable. (The problem also occurs with responsive media queries if the media breakpoints are in px units.)

You can set one dimension, usually the width, in px units, but the other should not be restricted so the box can expand along with the text, and other items on the screen must also be able to move down to make way for the expansion, so they mustn't be positioned with px units either.

If you can zoom to 200% on a particular screen and get away with it without overwriting anything, perhaps because there is enough empty space in your containers for the text to expand into, you're lucky, but this isn't normally the case.

Regards,
Guy Hickling

From: Olaf Drümmer
Date: Fri, Jun 17 2016 9:05AM
Subject: Re: text only zoom
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I'd definitely urge everybody to put the focus on responsive design. Just scaling the text may cause all kinds of hard to avoid issues (and wouldn't a vision impaired user want to see icons and other such stuff enlarged at the same time?). Good responsive design ensure that when using zoom, all aspects are zoomed reasonably well in relationship to each other and in relation to the view port, and of course, horizontal scaling should never become necessary.

In retrospect, text only zooming appears more like a workaround from times, when only few people would understand what responsive design is.

Olaf


> On 17.06.2016, at 16:45, Joseph Sherman < = EMAIL ADDRESS REMOVED = > wrote:
>
> Following up on this: Given that FireFox is the only browser that allows for Text-only zoom; that responsive design eliminates horizontal scrolling; and almost none of the sites I visited worked perfectly with 200% text-only zoom- Should text-only zoom still be a (high) concern?
>
>
> Joseph
>
> -----Original Message-----
> From: WebAIM-Forum [mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Guy Hickling
> Sent: Thursday, June 16, 2016 7:50 PM
> To: = EMAIL ADDRESS REMOVED =
> Subject: Re: [WebAIM] complex form questions
>
> Joseph,
>
> For your second question, normally, setting both height and width of a text container in px units is a definite no-no for accessibility.
> Text-only zoom, in any browser that allows it, for instance Firefox, is a very useful tool for people with poor sight because they can increase the text size but still keep the whole page within the window without having to scroll horizontally to read long lines of text, or other content. (IE11 no longer allows text-only zoom, IE10 did.) The WCAG specifies allowing upto 200% without corrupting content, but some users will go as high as their browser will allow.
>
> Unfortunately what happens is that, as the user increases the text size, the container can only remain the same size if it's dimensions are in pixels. This means text overflows outside it's container, overwriting whatever's to the right or below it. This is seen regularly on all too many sites, where one lot of text overwriting another lot makes both texts unreadable. (The problem also occurs with responsive media queries if the media breakpoints are in px units.)
>
> You can set one dimension, usually the width, in px units, but the other should not be restricted so the box can expand along with the text, and other items on the screen must also be able to move down to make way for the expansion, so they mustn't be positioned with px units either.
>
> If you can zoom to 200% on a particular screen and get away with it without overwriting anything, perhaps because there is enough empty space in your containers for the text to expand into, you're lucky, but this isn't normally the case.
>
> Regards,
> Guy Hickling
> > > > > > >

From: Chaals McCathie Nevile
Date: Fri, Jun 17 2016 9:58AM
Subject: Re: text only zoom
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On Fri, 17 Jun 2016 17:05:49 +0200, Olaf Drümmer < = EMAIL ADDRESS REMOVED = >
wrote:

> I'd definitely urge everybody to put the focus on responsive design.

Right…

> Just scaling the text may cause all kinds of hard to avoid issues (and
> wouldn't a vision impaired user want to see icons and other such stuff
> enlarged at the same time?). Good responsive design ensure that when
> using zoom, all aspects are zoomed reasonably well in relationship to
> each other and in relation to the view port, and of course, horizontal
> scaling should never become necessary.

Somewhere between 500% and 1000% there probably is a case for horizontal
scaling. And good responsive design needs to do more beyond 300% or so.

> In retrospect, text only zooming appears more like a workaround from
> times, when only few people would understand what responsive design is.

In memory, that's exactly what happened.

>> On 17.06.2016, at 16:45, Joseph Sherman < = EMAIL ADDRESS REMOVED = > wrote:
>>
>> Following up on this: Given that FireFox is the only browser that
>> allows for Text-only zoom; that responsive design eliminates horizontal
>> scrolling; and almost none of the sites I visited worked perfectly with
>> 200% text-only zoom- Should text-only zoom still be a (high) concern?

Responsive design that doesn't consider text-only zoom seems to be a bit
broken still.

Is text-only zoom really dead? I might be on a limb, but I'm not inclined
to write it off.

cheers

--
Charles McCathie Nevile - web standards - CTO Office, Yandex
= EMAIL ADDRESS REMOVED = - - - Find more at http://yandex.com

From: _mallory
Date: Sat, Jun 18 2016 4:29PM
Subject: Re: text only zoom
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On Fri, Jun 17, 2016 at 05:05:49PM +0200, Olaf Drümmer wrote:
> I'd definitely urge everybody to put the focus on responsive design. Just scaling the text may cause all kinds of hard to avoid issues (and wouldn't a vision impaired user want to see icons and other such stuff enlarged at the same time?).
Traditionally I did not want images to zoom with the text, and I was
a Firefox diehard until 3.6 for this reason among others. Trying to
read sharp clear text with something big and blurry next to it
made reading difficult. Now, if it's a problem, I turn off images
instead.

cheers,
_mallory

From: Alastair Campbell
Date: Mon, Jun 20 2016 10:02AM
Subject: Re: text only zoom
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Chaals McCathie Nevile wrote:

> I'd definitely urge everybody to put the focus on responsive design.
>>
>
> Right…


Definitely, and at last!


Responsive design that doesn't consider text-only zoom seems to be a bit
> broken still.
>

I'm not entirely clear what you mean here. It is very hard to do both, as
only RWD really gives you options for changing the layout when expanding.

With text-sizing it meant having buffers around text, but you need media
queries (or some very funky floats) to change the interface without RWD.

The only good examples I know of RWD sites that also handle text-sizing are
ones where it is made equivalent. For example (and from a quick look),
theguardian.com sizes everything in EMs, so zoom and text-sizing are the
same.

Does that help? In that case there is effectively no text-only sizing, as
images and layout also scale with text size.


Is text-only zoom really dead? I might be on a limb, but I'm not inclined
> to write it off.
>

The only reason (use-case) I've heard to use text-sizing in the context of
responsive design is _mallory's, where large blurry images are difficult to
deal with. Are there others?

To me, the solution for large blurry images would be to keep them sharp.
The picture element [1] seems to have good support now [2], perhaps we can
push for zoomed image to use the higher resolution versions?

-Alastair

1] http://www.html5rocks.com/en/tutorials/responsive/picture-element/
2] http://caniuse.com/#feat=picture

From: Jonathan Avila
Date: Mon, Jun 20 2016 10:26AM
Subject: Re: text only zoom
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> The only reason (use-case) I've heard to use text-sizing in the context of responsive design is _mallory's, where large blurry images are difficult to deal with. Are there others?

Another case to consider is some responsive implementations assume the user is on a mobile and hide, or layer functionality behind menus and focus on mobile tasks, etc. When in fact the low vision user may be accessing the site from a desktop and may not be on a touch screen, etc. I could also envision benefits to text resize for main body content but perhaps not other elements -- much like some browser's reader mode. Making assumptions based on the viewport width while not to specific to RWD could be an issue that people associate with the practice.

Jonathan

Jonathan Avila
Chief Accessibility Officer
SSB BART Group 
= EMAIL ADDRESS REMOVED =
703.637.8957 (Office)

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-----Original Message-----
From: WebAIM-Forum [mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Alastair Campbell
Sent: Monday, June 20, 2016 12:03 PM
To: WebAIM Discussion List
Subject: Re: [WebAIM] text only zoom

Chaals McCathie Nevile wrote:

> I'd definitely urge everybody to put the focus on responsive design.
>>
>
> Right…


Definitely, and at last!


Responsive design that doesn't consider text-only zoom seems to be a bit
> broken still.
>

I'm not entirely clear what you mean here. It is very hard to do both, as only RWD really gives you options for changing the layout when expanding.

With text-sizing it meant having buffers around text, but you need media queries (or some very funky floats) to change the interface without RWD.

The only good examples I know of RWD sites that also handle text-sizing are ones where it is made equivalent. For example (and from a quick look), theguardian.com sizes everything in EMs, so zoom and text-sizing are the same.

Does that help? In that case there is effectively no text-only sizing, as images and layout also scale with text size.


Is text-only zoom really dead? I might be on a limb, but I'm not inclined
> to write it off.
>

The only reason (use-case) I've heard to use text-sizing in the context of responsive design is _mallory's, where large blurry images are difficult to deal with. Are there others?

To me, the solution for large blurry images would be to keep them sharp.
The picture element [1] seems to have good support now [2], perhaps we can push for zoomed image to use the higher resolution versions?

-Alastair

1] http://www.html5rocks.com/en/tutorials/responsive/picture-element/
2] http://caniuse.com/#feat=picture