freetype2/docs/formats.txt

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This file contains a list of various font formats. It gives the
reference document and whether it is supported in FreeType 2.
file type:
The only special case is `MAC'; on older Mac OS versions, a `file'
is stored as a data and a resource fork, this is, within two
separate data chunks. In all other cases, the font data is stored
in a single file.
wrapper format:
The format used to represent the font data. In the table below it
is used only if the font format differs. Possible values are `SFNT'
(binary), `PS' (a text header, followed by binary or text data),
`LZW' (compressed with either `gzip' or `compress'), and
`BZ2' (compressed with `bzip2`).
font format:
How the font is to be accessed, possibly after converting the file
type and wrapper format into a generic form. Bitmap formats are
`BDF', `PCF', and one form of `WINFNT'; all others are vector
formats.
font type:
Sub-formats of the font format. `SBIT' and `MACSBIT' are bitmap
formats, `MM' and `VAR' support optical axes.
glyph access:
If not specified, the glyph access is `standard' to the font format.
Values are `CID' for CID-keyed fonts, `SYNTHETIC' for fonts which
are modified versions of other fonts by means of a transformation
matrix, `COLLECTION' for collecting multiple fonts (sharing most of
the data) into a single file, and `TYPE_0' for PS fonts which are to
be accessed in a tree-like structure.
FreeType driver:
The module in the FreeType library which handles the specific font
format. A missing entry means that FreeType doesn't support the
font format (yet).
Please send additions and/or corrections to wl@gnu.org or to the
FreeType developer's list at freetype-devel@nongnu.org (for subscribers
only). If you can provide a font example for a format which isn't
supported yet please send a mail too.
file wrapper font font glyph FreeType reference
type format format type access driver documents
----------------------------------------------------------------------------
--- --- BDF --- --- bdf 5005.BDF_Spec.pdf, X11
--- SFNT PS TYPE_1 --- type1 Type 1 GX Font Format
(for the Mac) [3]
MAC SFNT PS TYPE_1 --- type1 Type 1 GX Font Format
(for the Mac) [3]
--- SFNT PS TYPE_1 CID cid 5180.sfnt.pdf (for the Mac)
[3]
MAC SFNT PS TYPE_1 CID cid 5180.sfnt.pdf (for the Mac)
[3]
--- SFNT PS CFF --- cff OT spec, 5176.CFF.pdf
(`OTTO' format)
MAC SFNT PS CFF --- cff OT spec, 5176.CFF.pdf
(`OTTO' format)
--- SFNT PS CFF CID cff OT spec, 5176.CFF.pdf
MAC SFNT PS CFF CID cff OT spec, 5176.CFF.pdf
--- SFNT PS CFF SYNTHETIC --- OT spec, 5176.CFF.pdf
MAC SFNT PS CFF SYNTHETIC --- OT spec, 5176.CFF.pdf
--- SFNT TT SBIT --- sfnt XFree86 (bitmaps only;
with `head' table)
--- SFNT TT MACSBIT --- sfnt OT spec (for the Mac;
bitmaps only; `bhed' table)
MAC SFNT TT MACSBIT --- sfnt OT spec (for the Mac;
bitmaps only; `bhed' table)
--- SFNT TT --- --- truetype OT spec (`normal' TT font)
MAC SFNT TT --- --- truetype OT spec (`normal' TT font)
MAC SFNT TT VAR --- truetype GX spec (`?var' tables)
--- SFNT TT --- COLLECTION truetype OT spec (this can't be CFF)
MAC SFNT TT --- COLLECTION truetype OT spec (this can't be CFF)
--- --- PS TYPE_1 --- type1 T1_SPEC.pdf
(`normal' Type 1 font)
MAC --- PS TYPE_1 --- type1 T1_SPEC.pdf
(`normal' Type 1 font)
--- --- PS TYPE_1 CID cid PLRM.pdf (CID Font Type 0;
Type 9 font)
--- --- PS MM --- type1 5015.Type1_Supp.pdf
(Multiple Masters)
--- --- PS CFF --- cff 5176.CFF.pdf (`pure' CFF)
--- --- PS CFF CID cff 5176.CFF.pdf (`pure' CFF)
--- --- PS CFF SYNTHETIC --- 5176.CFF.pdf (`pure' CFF)
--- PS PS CFF --- --- PLRM.pdf (Type 2) [1]
--- PS PS CFF CID --- PLRM.pdf (Type 2) [1]
--- PS PS CFF SYNTHETIC --- PLRM.pdf (Type 2) [1]
--- --- PS --- TYPE_0 --- PLRM.pdf
--- --- PS TYPE_3 --- --- PLRM.pdf (never supported)
--- --- PS TYPE_3 CID --- PLRM.pdf (CID Font Type 1;
Type 10 font; never supported)
--- PS PS TYPE_14 --- --- PLRM.pdf (Chameleon font;
Type 14 font; never supported?)
--- --- PS TYPE_32 CID --- PLRM.pdf (CID Font Type 4;
Type 32 font; never supported?)
--- PS TT --- --- type42 5012.Type42_Spec.pdf
(Type 42 font)
--- PS TT --- CID --- PLRM.pdf (CID Font Type 2;
Type 11 font)
--- ? ? CEF ? cff ?
--- --- PCF --- --- pcf X11 [4]
--- LZW PCF --- --- pcf X11 [4]
--- BZ2 PCF --- --- pcf X11 [4]
--- --- PFR PFR0 --- pfr [2]
--- --- PFR PFR1 --- --- (undocumented, proprietary;
probably never supported)
--- --- WINFNT --- --- winfonts MS Windows 3 Developer's Notes
--- --- WINFNT VECTOR --- --- MS Windows 3 Developer's Notes
[1] Support should be rather simple since this is identical to `CFF' but
in a PS wrapper.
[2] Official PFR specification:
http://www.bitstream.com/categories/developer/truedoc/pfrspec.html
http://www.bitstream.com/categories/developer/truedoc/pfrspec1.2.pdf
The syntax of the auxiliary data is not defined there, but is
partially defined in MHP 1.0.3 (also called ETSI TS 101812 V1.3.1)
section 7.4.
http://www.etsi.org/
http://webapp.etsi.org/workprogram/Report_WorkItem.asp?WKI_ID=18799
(free registration required).
[3] Support is rudimentary currently; some tables are not loaded yet.
[4] See
THE X WINDOW SYSTEM SERVER: X VERSION 11, RELEASE 5
Elias Israel, Erik Fortune, Digital Press, 1992
ISBN 1-55558-096-3
for a specification given in Appendix D on pgs. 436-450. However,
this information might be out of date; unfortunately, there is no
PCF specification available online, and this book is out of print.
George Williams deduced the font format from the X11 sources and
documented it for his FontForge font editor:
http://fontforge.sourceforge.net/pcf-format.html
------------------------------------------------------------------------
Copyright 2004, 2005, 2008, 2009, 2010 by
David Turner, Robert Wilhelm, and Werner Lemberg.
This file is part of the FreeType project, and may only be used,
modified, and distributed under the terms of the FreeType project
license, LICENSE.TXT. By continuing to use, modify, or distribute this
file you indicate that you have read the license and understand and
accept it fully.
--- end of formats.txt ---