Re: [css3 fonts] font-specific features

On Sep 16, 2010, at 8:41 PM, John Daggett wrote:

>  <font-family> :== font family name, quoted or unquoted
>  <font-variant-value> :== the name of one of the font-specific font-variant values (e.g. swash, styleset, annotation)
>  <value-list> :== <value-name> <integer>+
>  <value-name> :== a user-defined identifier used to describe the numeric value
>  <integer> := an integer value greater than 0
> 
> Multiple integers would only be permitted for font-variant values that
> permitted multiple values (e.g. styleset, character-variant).  Other
> font-variant values would only permit a single value.
> 
>  @font-feature-values My Lovely Font {
>    swash: swishy 1, flowing 2;
>    stylistic: long-k 2;
>    styleset: alt-g 1, alt-m 3, curly-quotes 5, code 4 7 9;
>  }

This makes sense. The only part that I'm hung up on is  "code 4 7 9". How does that tie into the GSUB data? Does it mean this:

	ss04, ss07 and ss09 are all on for each glyph being processed

If so, how does the author specify a particular index from a GSUB Lookup Type 3 for a styleset?

Or does it mean:

	when processing ss04, if the glyph being processed is in the Coverage of a GSUB Lookup Type 3, replace the current glyph with the glyph at index 7 from the appropriate AlternateSet

If so, what does the 9 mean?

I'm probably missing something simple...

Tal