+++ /dev/null
- FreeType font driver for BDF fonts
-
- Francesco Zappa Nardelli
- <francesco.zappa.nardelli@ens.fr>
-
-
-Introduction
-************
-
-BDF (Bitmap Distribution Format) is a bitmap font format defined by Adobe,
-which is intended to be easily understood by both humans and computers.
-This code implements a BDF driver for the FreeType library, following the
-Adobe Specification V 2.2. The specification of the BDF font format is
-available from Adobe's web site:
-
- http://partners.adobe.com/public/developer/en/font/5005.BDF_Spec.pdf
-
-Many good bitmap fonts in bdf format come with XFree86 (www.XFree86.org).
-They do not define vertical metrics, because the X Consortium BDF
-specification has removed them.
-
-
-Encodings
-*********
-
-The variety of encodings that accompanies bdf fonts appears to encompass the
-small set defined in freetype.h. On the other hand, two properties that
-specify encoding and registry are usually defined in bdf fonts.
-
-I decided to make these two properties directly accessible, leaving to the
-client application the work of interpreting them. For instance:
-
-
- #include FT_INTERNAL_BDF_TYPES_H
-
- FT_Face face;
- BDF_Public_Face bdfface;
-
-
- FT_New_Face( library, ..., &face );
-
- bdfface = (BDF_Public_Face)face;
-
- if ( ( bdfface->charset_registry == "ISO10646" ) &&
- ( bdfface->charset_encoding == "1" ) )
- [..]
-
-
-Thus the driver always exports `ft_encoding_none' as face->charmap.encoding.
-FT_Get_Char_Index's behavior is unmodified, that is, it converts the ULong
-value given as argument into the corresponding glyph number.
-
-If the two properties are not available, Adobe Standard Encoding should be
-assumed.
-
-
-Anti-Aliased Bitmaps
-********************
-
-The driver supports an extension to the BDF format as used in Mark Leisher's
-xmbdfed bitmap font editor. Microsoft's SBIT tool expects bitmap fonts in
-that format for adding anti-aliased them to TrueType fonts. It introduces a
-fourth field to the `SIZE' keyword which gives the bpp value (bits per
-pixel) of the glyph data in the font. Possible values are 1 (the default),
-2 (four gray levels), 4 (16 gray levels), and 8 (256 gray levels). The
-driver returns either a bitmap with 1 bit per pixel or a pixmap with 8bits
-per pixel (using 4, 16, and 256 gray levels, respectively).
-
-
-Known problems
-**************
-
-- A font is entirely loaded into memory. Obviously, this is not the Right
- Thing(TM). If you have big fonts I suggest you convert them into PCF
- format (using the bdftopcf utility): the PCF font drive of FreeType can
- perform incremental glyph loading.
-
-When I have some time, I will implement on-demand glyph parsing.
-
-- Except for encodings properties, client applications have no visibility of
- the PCF_Face object. This means that applications cannot directly access
- font tables and must trust FreeType.
-
-- Currently, glyph names are ignored.
-
- I plan to give full visibility of the BDF_Face object in an upcoming
- revision of the driver, thus implementing also glyph names.
-
-- As I have never seen a BDF font that defines vertical metrics, vertical
- metrics are (parsed and) discarded. If you own a BDF font that defines
- vertical metrics, please let me know (I will implement them in 5-10
- minutes).
-
-
-License
-*******
-
-Copyright (C) 2001-2002 by Francesco Zappa Nardelli
-
-Permission is hereby granted, free of charge, to any person obtaining
-a copy of this software and associated documentation files (the
-"Software"), to deal in the Software without restriction, including
-without limitation the rights to use, copy, modify, merge, publish,
-distribute, sublicense, and/or sell copies of the Software, and to
-permit persons to whom the Software is furnished to do so, subject to
-the following conditions:
-
-The above copyright notice and this permission notice shall be
-included in all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
-IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
-CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
-TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
-SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-*** Portions of the driver (that is, bdflib.c and bdf.h):
-
-Copyright 2000 Computing Research Labs, New Mexico State University
-Copyright 2001-2002, 2011 Francesco Zappa Nardelli
-
-Permission is hereby granted, free of charge, to any person obtaining a
-copy of this software and associated documentation files (the "Software"),
-to deal in the Software without restriction, including without limitation
-the rights to use, copy, modify, merge, publish, distribute, sublicense,
-and/or sell copies of the Software, and to permit persons to whom the
-Software is furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in
-all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
-THE COMPUTING RESEARCH LAB OR NEW MEXICO STATE UNIVERSITY BE LIABLE FOR ANY
-CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT
-OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR
-THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-
-Credits
-*******
-
-This driver is based on excellent Mark Leisher's bdf library. If you
-find something good in this driver you should probably thank him, not
-me.
projects / reactos.git / blobdiff