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kc3-lang/freetype/docs/formats.txt
Alexei Podtelezhnikov
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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. Table fields ------------ 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 PFB binary PS a text header, followed by binary or text data LZW compressed with either `gzip' or `compress' 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. `PS' indicates third-order, `TT' second-order Bézier curves. font type Sub-formats of the font format. `SBIT' and `MACSBIT' are bitmap formats, `MM' and `VAR' support optical axes. `CFF2' supports optical axes also. glyph access If not specified, the glyph access is `standard' to the font format. Values are `CID' for CID-keyed fonts, `SYNTHETIC' for fonts that are modified versions of other fonts by means of a transformation matrix, 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). Notes ----- The SFNT container format also provides `collections' (usually having the file extension `.ttc' or `.otc'). A collection contains multiple font faces that share some tables to avoid redundancy, thus reducing the file size. In FreeType, elements of a collection can be accessed with a proper face index. Both the GX and the OpenType 1.8 variation fonts provide `named instances'. FreeType maps them to face indices (they can also be accessed with the standard MM interface). Other font formats (not using the SFNT wrapper) also provide multiple faces within one file; they are marked with an asterisk (`*') in the table below. FreeType can be configured to support Mac files (on older Mac OS versions, a `file' is stored as a data and a resource fork, that is, within two separate data chunks). If a file can't be opened as a font, FreeType then checks whether it is a resource fork, trying to extract the contained font data from either a `POST' or `sfnt' resource. 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. wrapper font font glyph FreeType reference format format type access driver documents ----------------------------------------------------------------------------- --- BDF --- --- bdf 5005.BDF_Spec.pdf, X11 SFNT PS TYPE_1 --- type1 Type 1 GX Font Format [7] (for the Mac; not supported) SFNT PS TYPE_1 CID cid 5180.sfnt.pdf (for the Mac) [3] SFNT PS CFF --- cff OT spec, 5176.CFF.pdf (`OTTO' format) SFNT PS CFF CID cff OT spec, 5176.CFF.pdf SFNT PS CFF SYNTHETIC --- OT spec, 5176.CFF.pdf SFNT PS CFF2 --- cff OT spec 1.8 SFNT TT SBIT --- sfnt XFree86 (bitmaps only; with `head' table) SFNT TT MACSBIT --- sfnt OT spec (for the Mac; bitmaps only; `bhed' table) SFNT TT --- --- truetype OT spec (`normal' TT font) SFNT TT VAR --- truetype GX spec (`?var' tables) SFNT TT VAR --- truetype OT spec 1.8 (`?var' + `?VAR' tables) WOFF --- --- --- cff, Compressed SFNT, ver. 1.0 [6] truetype WOFF2 --- --- --- cff, Compressed SFNT, ver. 2.0 [6] truetype --- PS TYPE_1 --- type1 T1_SPEC.pdf (PFA, Type 1 font resource) PFB PS TYPE_1 --- type1 T1_SPEC.pdf, 5040.Download_Fonts.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 CFF/MM --- cff old 5167.CFF.pdf (`pure' CFF) [3] --- PS* CFF/MM CID cff old 5167.CFF.pdf (`pure' CFF) [3] --- PS CFF/MM SYNTHETIC --- old 5167.CFF.pdf (`pure' CFF) [3] 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 PS CFF/MM --- --- PLRM.pdf (Type 2) [1] PS PS* CFF/MM CID --- PLRM.pdf (Type 2) [1] PS PS CFF/MM 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 Windows developer's notes [5] --- WINFNT VECTOR --- --- Windows developer's notes [5] [1] Support should be rather simple since this is identical to `CFF' but in a PS wrapper. [2] The official PFR specification is no longer available, but archive.org has archived it: https://web.archive.org/web/20091014062300/http://www.bitstream.com/font_rendering/products/truedoc/pfrspec.html https://web.archive.org/web/20081115152605/http://www.bitstream.com/font_rendering/pdfs/pfrspec1.3.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. https://www.etsi.org/ https://webapp.etsi.org/workprogram/Report_WorkItem.asp?WKI_ID=18799 [3] Support is rudimentary currently; some tables or data 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: https://fontforge.github.io/pcf-format.html [5] This is from MS Windows 3; see Microsoft's Knowledge Base article at https://support.microsoft.com/kb/65123 [6] Supported font formats are TrueType and OpenType fonts as defined in the OpenType specification 1.6 and newer. [7] `The Type 1 GX Font Format' (dated 1995-09-27) was distributed in Apple Developer CD-ROM in those days. The content of `TYP1' table is a PostScript Type 1 font without the eexec encryption. Current versions of FreeType don't not support this format, but FontForge can load it. ------------------------------------------------------------------------ Copyright (C) 2004-2024 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 --- Local Variables: coding: utf-8 End: