Re: [ft-devel] CID keyed fonts in sfnt wrappers in 2.3.8

[Werner LEMBERG]

> [...]  Another would be the one that I have ended up implementing by
> adding two methods to the cid service interface (pardon my FT
> vocabular -- I haven't spent more that one or two days in the source
> by now). One method to tell me whether a given font really is a CID
> keyed font, in the sense that we've agreed upon in the above.  And
> one method to map unicodes to cids for a given font.  The mapping
> information is already present in the charset.sids array on the
> internal cff font class, as far as I can tell.  So I just had to
> make sure that the sids array wasn't free'd too early and make
> export the mapping via my the cid service.

This sounds like the right solution to me.  Can you post patches?

>> I suppose the change was introduced on 2008-07-16.

Yes.  The old behaviour was not `correct' in the sense that fonts
wrapped in SFNT only expose the cmap.  Unwrapping for different
purposes must be handled differently.

>> If I'm asked to implement the compatibility feature to ignore
>> "cmap" in CFF OpenType, I will modify cffobjs.c:cff_face_init(),
>> and insert a hook to skip calling sfnt->load_cmap().  I can pass
>> some parameters to cff_face_init() by num_params and params[], so I
>> should discuss the introduction of new tag name to ignore "cmap" in
>> CFF OpenType, something like FT_PARAM_TAG_IGNORE_SFNT_CMAP.

This is a different solution to the problem -- however, there might be
situations where you need both the cmap and CID-keyed mappings.  With
your suggestion you have to load the font twice, as far as I can see,
whereas Michael's idea avoids that.


    Werner