[Fontconfig] Granular synthetic emboldening possible ?

[Akira TAGOH]

On Wed, Jan 23, 2019 at 4:02 PM Werner LEMBERG <wl at gnu.org> wrote:
> Ha, he was there, and I sent him to this list :-)

Oh, really.

> If I understand everything correctly he wants to achieve the
> following: Let's assume that normal shape is value 0 and fully
> emboldened is value 100.  If he is asking for a font with bold
> value N, he wants that fontconfig returns a font that is a bit bolder,
> for example a font corresponding to bold value N + 5.

fontconfig only provides a boolean value for emboldening. How those
information is used is really up to rendering libraries or
applications though, this boolean value is typically used to call
FT_GlyphSlot_Embolden API. there should be nothing more than that at
this moment. so even if modifying a weight in fontconfig, it won't
take any effects AFAIK.
Or is there any way to adjust a weight for emboldening? if there are,
aims should be accomplished with own config as long as
applications/libraries supports it. if not... I'm afraid there isn't
too much we can do.

>
> While FreeType can embolden fonts, it's a very limited operation
> because it can cause ugly artifacts.  The only other thing FreeType
> can offer is stem darkening at smaller sizes for CFF (and I told him
> that already).
>
>
>     Werner



-- 
Akira TAGOH