[Fontconfig] A question about font styles

[Owen Taylor]

Ambrose Li wrote:
> On Mon, Mar 07, 2005 at 08:40:42AM -0500, Owen Taylor wrote:
> 
> 
>>What font is selected when those conflict?
> 
> 
> For the particular example I gave in the bug, the font with
> lining figures is always selected.  I don't know why this is the
> case; the "expert" one not being selected is probably because
> it's not complete, but I don't know why it would not select the
> font with oldstyle figures (perhaps it's slightly incomplete too).

That was a rhetorical question :-). I dont' think there is
a reasonable answer. (Prior art of fontconfig not withstanding.)

The question of multiple fonts that are the "same" but have
different glyph repetoires (like an expert font), or different
glyph variants (old-style vs. lining) is a difficult one.
The future here is OpenType fonts where everything is combined
into one font.

I don't know if it makes sense to try and combine multiple Type1
fonts under the hood. Clearly, having to specifically select
the expert font for a few characters to get old style numbers
or ffi ligatures isn't a good user interface. But I'd worry
that we'd just outsmart ourselves here. Expert font tend,
in my experience, to be each slightly different.

> BTW, "Apollo MT" is a very mild example. I have another typeface
> "Poetica Chancery" with 21 fonts which is much worse: in gimp 2,
> it appears as 3 instances of "Poetica" (always the same capitals
> font) and 18 instances of "Poetica Italic" (always the same
> italic [i.e., cursive] font). And all these (all of them having
> the same weight and the same slant, except the capitals because
> originally italic faces had the property that lowercase letters
> are slanted but uppercase letters are not slanted) should either
> be in the same family (just "Poetica", but have to be able to
> select any of the 21) or else split to 21 distinct families in
> order to be useful.
> 
> My feeling is that trying to map everything to the CSS model is
> hopeless, unless we want to create fake font families on the fly.

That's exactly what I think we should do. Note that I'm proposing
considerably *less* "fake" font families than what Windows does,
since windows only allows four variants (bold/italic/bold italic)
of each family.

> Mapping font properties to CSS properties might be somewhat
> fruitful, but most commercial Type 1 fonts have variants that
> bear absolutely no relationship to CSS properties.

"Most"? "absolutely no"? I would dispute that. Most font variants
are in fact quite representable in the CSS model.

If you browse, say, through the Adobe type libary, you'll find
that 90+% of the fonts fall into the CSS model.

Something like Poetica is going to be a mess to handle
no matter how we encode it. "Poetica Ampersands"???

  there are
> also some more surprising inventions from the commercial font
> world, such as typefaces that distinguishes between two variants
> of small caps (e.g., Emigre's "Mrs Eaves").  With the current
> behaviour, commercial fonts are almost completely useless.

Clearly having every face be accessible is a necessary goal.

Regards,
					Owen