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Re: Using SVG to display text

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From: Patrick H. Lauke
Date: Jun 8, 2019 5:46AM

On 08/06/2019 10:12, Léonie Watson via WebAIM-Forum wrote:
> On 08/06/2019 07:02, Steve Green wrote:
>> I am working on a truly horrible e-learning application in which all
>> the text has been implemented using SVG <text> elements. With respect
>> to WCAG success criterion 1.4.5 (Images of Text), would you consider
>> such content to be text or an image of text?
>>
>> To me, it seems to be in between. The <text> element supports some CSS
>> styles (such as font size), but does not support others (such as
>> line-height), so it cannot be visually customized to the user's
>> requirements.
>>
>> I would like to say this violates 1.4.5, but I would welcome other
>> opinions.
>
> I don't think this fails the letter of 1.4.5. The browser considers the
> content of a <text> element as text, it's exposed in the accessibility
> API as text, and it fits the normative description of text in WCAG:
>
> "sequence of characters that can be programmatically determined, where
> the sequence is expressing something in human language"
>
> It may fail the spirit of 1.4.5 if the <text> element isn't styled using
> CSS though, and cannot therefore be visually customised for font, size,
> colour and background (as the SC requires). The inability to adjust line
> height would likely be a fail of 1.4.12 rather than 1.4.5 though.

The point of 1.4.5 isn't whether or not it's exposed as text though (to
the accessibility API or anything else), but whether or not users can
"distinguish" the text including adapting it to their need. While SVG
text remains crisp when zoomed (one aspect/reason often given for not
using text as images, in that "it pixelates when zoomed"), it can't be
adapted (can't currently change font, spacing, etc). And this is more
the point of the SC, but - as many SCs in 2.0, and even in 2.1 - the
original intent/meaning has probably been wordsmithed out of the
normative text in the end, leaving the normative part very vague. But if
you skim over the understanding doc
https://www.w3.org/WAI/WCAG21/Understanding/images-of-text.html there's
a lot of intent there about being customisable, which unless the author
has also provided a custom mechanism, won't be possible with current
user agents (e.g. in browser, setting some font override or whatever,
won't affect the font used inside the SVG)

P
--
Patrick H. Lauke

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