Re: [ft-devel] Make FT_GlyphSlot_Embolden standard API?

[Chia I Wu]

On Fri, May 13, 2005 at 11:44:59AM +0900, address@hidden wrote:
> Hi
> 
> On Thu, 12 May 2005 23:44:11 +0800
> Chia I Wu <address@hidden> wrote:
> >As fontconfig and xft already have the code to "embolden" and rely on
> >FT_GlyphSlot_Embolden to do the real job, I think FT_GlyphSlot_Embolden
> >should be made standard API. This is an important feature for Chinese
> >(maybe also Japanese and Korean) users, as most Chinese fonts don't have
> >a real bold style.
> >
> >What do you think?
> 
> I'm unfamiliar with this API and never checked the bolden result in
> detail, could you show some demo program?
I've made a quick hack to ftview.c for demo. See applied patch.
> 
> As you pointed out, most CJK font family does not provide "bold" style.
> I think "weight" (XXX-Light, XXX-Medium, XXX-Heavy etc) - may take
> similar role of it in the typographical viewpoint. But, most personal
> computers are shipped with only 1 or 2 fonts for each CJK scripts,
> and synthesized "bold" is often used in documents generated by PC.
The only commercial fonts I own are Dynaware's. They have severial
weights for each family, named by XXX-W3, XXX-W4, XXX-W5, etc. But no
application take advantage of that to get better quality.

Also, the size of a Chinese font is very large, ranaging from 5MB to
25MB (the 25MB one includes glyphs of both traditional and simplicial
Chinese). I personally prefer synthesized bold than having all those
weights installed.

> 
> Considering there is such root of embolding request, I wonder whether
> FT_GlyphSlot_Embolden() API is already enough for the purpose. It does
> not receive much parameters to control embolding (am I misunderstanding?).
> I'm afraid several control parameters are requested in future, for example:
> 
> * strength to embolding
I think this is important.
> * switch to enable/disable changing glyph metrics in embolding
> * switch to enable/disable embolding of bitmap font
I think glyph metrics should be changed automagically. Bitmap glyph
should be emboldened automatically too. As we are synthesizing, you know
you can't expect a high-quality result, thus it makes no difference
which format the glyph is in.
> * choosing embolding algorithm
> 
BTW, I have done some experiment to embolden a bitmap glyph, by printing
the same glyph severial times (depending on strength), with starting
point shift to the right by 1 pixel each time. The result is ok.
> How do you think of?
> 
> Regards,
> mpsuzuki

ftview-embolden.patch
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