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1                  FreeType font driver for PCF fonts
2
3                       Francesco Zappa Nardelli
4                  <francesco.zappa.nardelli@ens.fr>
5
6
7Introduction
8************
9
10PCF (Portable Compiled Format) is a binary bitmap font format, largely used
11in X world. This code implements a PCF driver for the FreeType library.
12Glyph images are loaded into memory only on demand, thus leading to a small
13memory footprint.
14
15Information on the PCF font format can only be worked out from
16`pcfread.c', and `pcfwrite.c', to be found, for instance, in the XFree86
17(www.xfree86.org) source tree (xc/lib/font/bitmap/).
18
19Many good bitmap fonts in bdf format come with XFree86: they can be
20compiled into the pcf format using the `bdftopcf' utility.
21
22
23Supported hardware
24******************
25
26The driver has been tested on linux/x86 and sunos5.5/sparc.  In both
27cases the compiler was gcc.  When back in Paris, I will test it also
28on linux/alpha.
29
30
31Encodings
32*********
33
34Use `FT_Get_BDF_Charset_ID' to access the encoding and registry.
35
36The driver always exports `ft_encoding_none' as face->charmap.encoding.
37FT_Get_Char_Index() behavior is unmodified, that is, it converts the ULong
38value given as argument into the corresponding glyph number.
39
40
41Known problems
42**************
43
44- dealing explicitly with encodings breaks the uniformity of FreeType 2
45  API.
46
47- except for encodings properties, client applications have no
48  visibility of the PCF_Face object.  This means that applications
49  cannot directly access font tables and are obliged to trust
50  FreeType.
51
52- currently, glyph names and ink_metrics are ignored.
53
54I plan to give full visibility of the PCF_Face object in the next
55release of the driver, thus implementing also glyph names and
56ink_metrics.
57
58- height is defined as (ascent - descent).  Is this correct?
59
60- if unable to read size information from the font, PCF_Init_Face
61  sets available_size->width and available_size->height to 12.
62
63- too many english grammar errors in the readme file :-(
64
65
66License
67*******
68
69Copyright (C) 2000 by Francesco Zappa Nardelli
70
71Permission is hereby granted, free of charge, to any person obtaining
72a copy of this software and associated documentation files (the
73"Software"), to deal in the Software without restriction, including
74without limitation the rights to use, copy, modify, merge, publish,
75distribute, sublicense, and/or sell copies of the Software, and to
76permit persons to whom the Software is furnished to do so, subject to
77the following conditions:
78
79The above copyright notice and this permission notice shall be
80included in all copies or substantial portions of the Software.
81
82THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
83EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
84MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
85IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
86CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
87TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
88SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
89
90
91Credits
92*******
93
94Keith Packard wrote the pcf driver found in XFree86.  His work is at
95the same time the specification and the sample implementation of the
96PCF format.  Undoubtedly, this driver is inspired from his work.
97