Re: What's an em

Chris Lilley wrote:
> Clive Bruton wrote:
> 
> > I think then the document creator should have used alternatives, some of
> > which were guaranteed to be on the system.
> 
> The fonts guaranteed to be on the system are the five CSS generic font
> families, and ther eis noindication what these look like or even if they
> are all distinct.

More's the pity.
The font-matching algorithm says:

[T]he UA default style sheet [...] is considered to have full @font-face
rules for all fonts which the UA will use for default presentation, plus
@font-face rules for the five special generic font families (see
'font-family') defined in CSS2 [sic ([.])]
but this seems to me to be wrong.

For example, say I have P {font-family: cursive}. The UA is required to
have an @font-face rule for cursive. In Opera for example, it is mapped
to Times New Roman. This makes pages very ugly.

I think it would be better to allow P {font-family: cursive,
sans-serif}, and not have the necessity of five @font-face rules.

Further to this, imagine you want an oblique font if possible, but an
italic one failing that. There is no way to express this - italic is
matched by oblique fonts, but oblique fonts not by italic ones:

<q>
'font-style' is tried first. 'italic' will be satisfied if there is
either a face in the UA's font database labeled with the CSS keyword
'italic' (preferred) or 'oblique'. Otherwise the values must be matched
exactly or font-style will fail.
</q>

This severely limits the utility of font-style: oblique because most
people don't have oblique fonts, and for these people it would be useful
to state that an italic one should be used instead; e.g., by the
(backwards-incompatible) font-style: oblique, italic.