Font-adjust: a CSS enhancement proposal

I've been thinking (and making noise) about the matter of different fonts
having greatly-varying legibility characteristics at the same nominal size
(whatever the unit), and the accessibility and aesthetic problems this
poses when the "first-choice" font is not available (i.e., when font
substitution occurs). This problem is distinct from the one of using
absolute or device-dependent units like points or pixels for type sizes.

David Perrell and I have suggested in the past that CSS be extended to
permit a binding of alternate sizes and line-heights to alternate font
choices, but our proposed functionality and syntax[1] was passed over for
various reasonable reasons. I think I may have hit upon a solution in the
form of a few new (CSS2?) properties: "font-size-adjust",
"line-height-adjust", and "font-weight-adjust". Mirroring the current
"font" syntax, the shorthand expression for all three could be
"font-adjust".

I've written all of this up here, with exhibits, and look forward to your comments:

http://www.verso.com/agitprop/fontadjust/

Summary: font-adjust provides a simple means to preserve the legibility and
much of the readability characteristics of rendered text when a
stylesheet's "first-choice" font is not available, and font-substitution
occurs. Adjustments are based on differences between (a) the ratios of em-
to ex-heights and (b) the weights, of "first-choice" and substituted fonts.
Font-adjust could vastly increase the range of prudent choices for type
specification in stylesheets, advancing "font-independent typography" for
the Web.


[1] http://lists.w3.org/Archives/Public/www-style/1997Jun/0067.html , 
http://lists.w3.org/Archives/Public/www-style/1997Jul/0197.html etc.


Todd Fahrner
mailto:fahrner@pobox.com
http://www.verso.com/agitprop/

The printed page transcends space and time. The printed page, the infinitude of books, must be transcended. THE ELECTRO-LIBRARY.
	- El Lissitzky, 1923

Received on Friday, 12 December 1997 18:31:33 UTC