[ft-devel] patch for Type1 Unicode cmap on Windows

[Sergey Tolstov]

Hello,

Type 1 driver uses Adobe Glyph List to build the Unicode cmap.
Windows GDI creates a little different mapping. For example, if there is
'periodcentered' glyph name in the Type 1 font, Windows maps 0x2219 to
that glyph and freetype does not.
I have run AGL 2.0 and WGL4 through a script and found that there are
the following glyph names in WGL4, which are mapped to additional
Unicode values:
Delta   0x0394
Omega   0x03A9
fi      0xF001
fl      0xF002
fraction        0x2215
hyphen  0x00AD
macron  0x02C9
mu      0x03BC
periodcentered  0x2219
space   0x00A0
uni203E 0x203E

Out of these, the fl and fi are not mapped by Windows, and uni203E can
be omitted. This leaves 8 WGL specific mappings.
Delta: 0x0394
Omega: 0x03A9
fraction: 0x2215
hyphen: 0x00AD
macron: 0x02C9
mu: 0x03BC
periodcentered: 0x2219
space: 0x00A0

I suggest you to consider a patch for the psmodule.c, which maps these
glyph names on top of regular AGL mapping. The mapping is created if the
glyph name is present in the font, and the Unicode value is not assigned
by the AGL mapping. The patch is made on top of 2.3.5.
During testing with a font, named Agate, 6 additional entries are being
created in the unicode cmap (for 2215, AD, 2C9, 3BC, 2219, A0). With the
patch, freetype maps those unicodes in the same way as GDI. Those
unicodes are mapped to 0 without the patch.

Thanks,
Sergey Tolstov

psmodule.c
Description: psmodule.c