Re: SVG12: computed value of font-weight vs uDOM

On Fri, 9 Jun 2006, Chris Lilley wrote:
> [...] what concerns me is that the same section also says
>   Child elements inherit the resultant weight, not the keyword value.
> which, assuming that it is the computed value which is inherited, 
> implies that a value like "100 bolder bolder" is both required and 
> disallowed. Could you clarify?

It is not allowed syntactically. It is, however, inherited. (It is always 
the computed value that is inherited.)

> And does "combined" mean "concatenated" or "concatenated with spaces in 
> between" or some other form of combination?

You seem to be mistaking the concept of the value space with the concept 
of the lexical space. (This is a confusion that I have run into before 
with members of the SVG working group. Maybe SVG does not have the 
distinction?) There is no lexical representation of the computed value of 
the 'font-weight' property in CSS.

> For the sake of discussion, lets pretend that we are using the
> "Rattlesnake" font family from the CSS spec. "Rattlesnake Regular"
> covers 100, 200, 300 and 400. After all, the precise value would depend
> on the font and what weights it provides. Lets use that with your
> earlier example, and consult CSS 2.1 to find that:
>   'bolder' selects the next weight that is assigned to a font that is
>   darker than the inherited one. If there is no such weight, it simply
>   results in the next darker numerical value (and the font remains
>   unchanged), unless the inherited value was '900' in which case the
>   resulting weight is also '900'.
> So this means that bolder, bolder from 100 goes "Rattlesnake Medium"
> then "Rattlesnake Bold". Does that result in 600 or 700 (the same face
> covers both)? It seems that it should take 600. So for this case, the
> computed value would be 600.

No. The computed value is "one level bolder than 100". If one of the 
descendant elements (which inherits this value) has 9 font weights, then 
its "200" value will be used, not 600.

Ian Hickson               U+1047E                )\._.,--....,'``.    fL       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'

Received on Friday, 9 June 2006 20:24:46 UTC