Re: [css3-fonts] font selection for Unicode Variation Selector

[bcc'd to mpeg-OTspec]

Asmus Freytag wrote:

> In this context, the way a CSS statement like
>  font-family: 'My Favorite Font', 'Some generic font', 'Special IVS 
> Font', 'Generic IVS Font';
> ought to work is that it sets up a composite font selection on the fly.

> Each grapheme cluster would then be rendered at the first font 
> encountered that is able to render it.

But using an actual composite font, perhaps it could be possible to 
define which grapheme clusters are rendered by which component fonts, 
avoiding the problem that I understood Koji-san to be be describing, in 
which the preferred rendering of individual grapheme clusters might not 
be capturable by fallback ordering. Taking your font-family order, for 
example, what if both 'Special IVS Font' and 'Generic IVS Font' were 
able to render grapheme clusters foo and bar, but the preferred 
rendering for foo is that provided by 'Special IVS Font' and the 
preferred rendering for bar is that provided by 'Generic IVS Font'.

At the moment, if I recall correctly, the proposed composite font format 
only specifies which Unicode ranges would be rendered by which component 
font, but it seems to me that it might be desirable to be able to 
specify individual variation selector sequences as overrides.


Received on Saturday, 26 February 2011 20:35:05 UTC