Re: [ft-devel] Adobe CFF hinter for type 1 fonts

[Dave Arnold]

On 5/4/2013 10:54 PM, Werner LEMBERG wrote:
> > As far as I understand, both Type 1 fonts and CFF use the same or
> > similar rendering.
> >
> > Would it be possible to use the new Adobe engine for type 1 fonts?
> > The are currently quite a few bugs open about the rendering quality
> > of type 1 fonts and I've noticed poor hinting with the ghostscript
> > fonts.
> Indeed, this would be a good thing.  Dave, can you comment on the
> hinting differences between Type 1 and CFF, and whether the new CFF
> code would be suitable for hinting Type 1 fonts?
>
>
>      Werner
It is true that Type 1 hints and CFF hints are very similar. Some of the 
techniques we used in the Adobe CFF code could be applied to Type 1, but it 
would be a significant effort. The structure of the charstrings are different. 
For example, CFF requires all hints to be declared at the beginning of the 
charstring; in Type 1 they can be declared anywhere.

The CFF code that Adobe contributed to FreeType was originally written as a 
CFF-only interpreter. This contributed to keeping the code small and simple. It 
is possible to combine Type 1 and CFF interpreters, but that's a non-trivial 
change.

I understand the need to support legacy Type 1 fonts but I think more users 
today are interested in Open Type fonts, and that calls for TrueType or CFF 
outlines.

-Dave