RE: [Freetype] Question on MacOS X

[Changyuan Hu]

> >According to the FreeType2 API, the only Mac-specific API is 
> >FT_New_Face_From_FOND, which requires a Handle to FOND resource.
> 
>          True, but the standard FT_New_Face() on the Mac goes through some 
> special processing to provide transparent support for Mac OS fonts.  I 
> would recommend that you use that call instead, so that FT can deal with 
> all the complexities for you.

Function FT_New_Face() requires font file path name as input. That is almost 
useless for a serious application in Windows or Mac, in which you would allow 
user to choose font from family name, style and size, but not from font file 
selection. It is the same case in Windows, where you probably use Windows 
standard ChooseFont() to open standard font selection dialogue and upon return, 
you get the handle to the selected font. Because the Windows ChooseFont() 
function uses special algorithm to map user requirement to the font Windows 
sees as the best match, using a file dialog to let user choose a font file 
directly is not such a nice solution. (That is why I still did not use FreeType 
in my Windows application.)

So, I have to use Mac native way to open a font, i.e. passing a FOND resource 
handle to FT_New_Face_From_FOND(). Macintosh dev technical note TN2024 has a 
detailed explaination on how to open the FOND resource hand from both the 
traditional resource-fork font and the new data-fork font (.dfont).

By the way, the patch code in FT2 version ftmac.c to allow parse_font find a 
face which is not the first one in FOND resource seems not complete. It still 
does not support style (normal, italic, bold and bold-italic). Some FOND 
contains sfnt resource of all the four possible styles (such as Times). So, we 
should loop into the AsscEntry array to find the best fit. I did this patch for 
the FT1.2.2 code locally and of course I added the style argument in the 
FT_New_Face_From_FOND() function. Following is my local modification.

  void parse_fond(  char*   fond_data,
                    short   style,
                    short*  have_sfnt,
                    short*  sfnt_id,
                    Str255  lwfn_file_name )
  {
    AsscEntry*  assoc;
    FamRec*     fond;
    short       nb_assoc;
    int         i;


    *sfnt_id          = 0;
    *have_sfnt        = 0;
    lwfn_file_name[0] = 0;

    fond = (FamRec*)fond_data;
    nb_assoc = *(short*)( fond_data + sizeof ( FamRec ) ) + 1;
    assoc = (AsscEntry*)( fond_data + sizeof ( FamRec ) + 2 );

    for( i = 0; i < nb_assoc; i++ )
    {
      if ( assoc->fontSize == 0 && assoc->fontStyle == style )
      {
        *have_sfnt = 1;
        *sfnt_id = assoc->fontID;
        break;
      }
      assoc++;
    }
   .... the rest of this function is not changed.

Good weekend!

Changyuan Hu
>>>www.MindAvenue.com<<<