Re: [ft-devel] Getting the kerning pairs in under O(n*n)

[Adam Twardoch (List)]

On 12-10-05 06:49, Werner LEMBERG wrote:
>> WL> OK.  So FreeType should obey the `gasp' table by default?  Or
>> should WL> this be a new FT_LOAD flag?  Or a rendering flag?
>>
>> Please not by default.  I *NEVER* want monochrome rendering when I
>> use aa.
> But some fonts are *designed* to obey the gasp table!  In particular
> there are fonts which are rendered incorrectly in case you don't
> follow the gasp.  As a default, I can imagine to use auto-hinting for
> those ranges where the gasp table says `bi-level' and the user asks
> for `anti-aliasing'.
I would say that "gasp" should be active and obeyed if TT bytecode
hinting is being executed.

If the FreeType autohinter is used, then it doesn't make sense.

The whole point of the "gasp" table is that it's *part of the TrueType
hinting infrastructure". Ignoring it makes as much sense as ignoring
"cvt" but executing "prep", or something like that.

If FreeType autohinting is used, then it's obvious that the
"developer-designed hinting" is ignored. In such a case, it's safe to
assume that "gasp" should not be part of the process either.

These days, I feel that an even more important aspect is the y-smoothing
in ClearType. The "gasp" flags were clearly designed to work in
conjunction with ClearType, and using the y-smoothing flag in ClearType
DW wisely certainly produces better results than just ignoring it.

Best,
Adam

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May success attend your efforts,
-- Adam Twardoch
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