bug#5869: [Aquamacs-bugs] Re: incorrect fontification of non-ascii chars on Mac OS X 10.4

[YAMAMOTO Mitsuharu]

>>>>> On Wed, 29 Jun 2005 17:59:01 +0100, David Reitter 
>>>>> <david.reitter@gmail.com> said:

>>> Well, create-fontset-from-mac-roman seems to create fontsets with
>>> fonts only drawn from the 'roman' type.

>> Could you give me a concrete example?

> I didn't try it out (don't use cyrillic fonts etc.), but I looked at
> the name of the function and at the code, which uses

> (create-fontset-from-ascii-font font resolved-font fontset-name)

> The documentation says that this function 'Create[s] a fontset from
> an ASCII font font", which I take to be roman only.  But let me know
> if I'm mistaken there. I don't know much about the whole font
> business...

Please don't just guess.  Fontsets defined with
create-fontset-from-ascii-font can also display non-ascii fonts (if
corresponding fonts are installed).  Unspecified parts are
complemented using the data in "fontset-default" and others.

I've been using fontsets defined with
create-fontset-from-mac-roman-font and I can display CJK characters as
well as mac-roman, mac-centraleurroman, mac-cyrillic, mac-symbol, and
mac-dingbats characters.

>> As for the "tons of wrong glyphs" problem, I think that's due to a
>> misuse of the function, rather than a bug.  The function
>> create-fontset-from-fontset-spec is suitable only for the case that
>> all the characters in a single charset are displayed with a single
>> font.  But that's not the case for fonts in Mac encodings.

> Uuh, oh - the documentation of create-fontset-from-fontset-spec
> doesn't say so. Maybe it's a documentation bug then :)

I think the format of the FONTSET-SPEC argument implicitly says that.

  FONTSET-SPEC is a string of the format:
        FONTSET-NAME,CHARSET-NAME0:FONT-NAME0,CHARSET-NAME1:FONT-NAME1,...
        
Moreover, we usually don't have to care about that on X11.

> So what should we use to define a fontset that contains roman and
> non- roman fonts for a variety of charsets?  That's quite relevant,
> because at least a few standard fontsets need to support everything.

  (create-fontset-from-mac-roman-font
   "-*-FAMILY-medium-r-normal--SIZE-*-*-*-*-*-mac-roman" nil "NAME")

would do the right thing for normal use.  If one also want to use ETL
fonts, one can refer to how "fontset-mac" is defined.

> If you look at carbon-font.el by T. Hiromatsu, you'll see a lot of
> (undocumented or documented-in-Japanese) code that deals with fonts,
> using create-fontset-from-fontset-spec. I assume you have a better
> idea about what's going on there...

I've no idea about its intention.  It also introduces tons of wrong
glyphs...

                                     YAMAMOTO Mitsuharu
                                mituharu@math.s.chiba-u.ac.jp