Am 06.06.2018 um 19:32 schrieb Thorsten Froehlich:
> "Thorsten Froehlich" <nomail@nomail> wrote:
>> I won't dispute your results because they don't surprise me, but I dispute the
>> fact that the code behaves unpredictably:

I never used the word "unpredictably" - I used the phrase "according to
obscure rules". As in, "pretty difficult to guess without looking at the
actual code and maybe the font file".

>> The code is in OpenFontFile, and it
>> does pick the Unicode tables as top priority if Unicode is specified as text
>> format. It only falls back to MacRoman (which next to all TTFs contain for
>> legacy reasons) if it cannot find any of the Unicode formats that it does
>> support. So the real question is if maybe in the 18 years since this code was
>> introduced in 3.5 based on TTFs shipped with Mac OS 9 and Windows 2000, some
>> other TTF Unicode formats were introduced that the code does not support...
> 
> To answer my own questions, the formats did change...
> https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6cmap.html
> 
> So what you see is the code falling back to a ASCII (MacRoman) code tables as a
> fail-safe because it cannot use the newer Unicode tables most current fonts seem
> to contain.

Um... I do /not/ really think so... you know, the font that I found to
be ok (with `charset utf8`) is the Microsoft Arial font on my Windows 10
machine, while the other is POV-Ray's cyrvetic.ttf. So I have a hunch
that the ok font /may/ be the newer one.

So I'd guess ye olde cyrvetic.ttf never had a Unicode table to begin with.

Also, I don't see a fallback to Mac Roman in the cyrvetic font, but
rather a fallback to Mac Cyrillic.


(As it turns out, the POV-Ray TrueType font gives a rat's arse about the
platformSpecificID when looking for a code table it can use; platformID
is all it tests for.)

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