Re: [css3-fonts] proposal for 'font-size-adjust: auto'

On Thu, Mar 18, 2010 at 2:13 PM, L. David Baron <dbaron@dbaron.org> wrote:
> I'd like to propose an additional value for the 'font-size-adjust'
> property, in addition to the current 'none' and <number> values:
>
>  'auto'
>     Behaves just like <number>, except the number to use is the
>     aspect value of the first font in the initial value of the
>     'font-family' property.  Instead of the first font, user agents
>     may use a different font in that list (the initial value of
>     'font-family') based on what character ranges the fonts in the
>     list provide and the language of the document or content.
>
> This 'auto' value has two major use cases that I can see:
>
>  (1) It works better than <number> for authors who want the evening
>  out of x-heights between fonts (particularly monospace and
>  non-monospace) but want to use sizes that are relative to the
>  user's default font size.  Using <number> essentially multiplies
>  the user's default font size by an unknown adjustment factor, which
>  'auto' does not.
>
>  (2) It can be useful as an initial value for user agents,
>  particularly as a replacement for the current hacks through which
>  some user agents use a different default font size for monospace
>  and non-monospace fonts.
>
> I think it may even make sense to change the spec such that 'auto'
> is an allowed initial value for 'font-size-adjust' (in addition to
> 'none').

I like it.  The <number> value is also simply more difficult to use,
as you need to experimentally determine the x-height of your first
font yourself.

~TJ

Received on Friday, 19 March 2010 00:24:46 UTC