1 FreeType font driver for PCF fonts 2 3 Francesco Zappa Nardelli 4 <francesco.zappa.nardelli (a] ens.fr> 5 6 7 Introduction 8 ************ 9 10 PCF (Portable Compiled Format) is a binary bitmap font format, largely used 11 in X world. This code implements a PCF driver for the FreeType library. 12 Glyph images are loaded into memory only on demand, thus leading to a small 13 memory footprint. 14 15 Information 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 19 Many good bitmap fonts in bdf format come with XFree86: they can be 20 compiled into the pcf format using the `bdftopcf' utility. 21 22 23 Supported hardware 24 ****************** 25 26 The driver has been tested on linux/x86 and sunos5.5/sparc. In both 27 cases the compiler was gcc. When back in Paris, I will test it also 28 on linux/alpha. 29 30 31 Encodings 32 ********* 33 34 Use `FT_Get_BDF_Charset_ID' to access the encoding and registry. 35 36 The driver always exports `ft_encoding_none' as face->charmap.encoding. 37 FT_Get_Char_Index() behavior is unmodified, that is, it converts the ULong 38 value given as argument into the corresponding glyph number. 39 40 41 Known 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 54 I plan to give full visibility of the PCF_Face object in the next 55 release of the driver, thus implementing also glyph names and 56 ink_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 66 License 67 ******* 68 69 Copyright (C) 2000 by Francesco Zappa Nardelli 70 71 Permission is hereby granted, free of charge, to any person obtaining 72 a copy of this software and associated documentation files (the 73 "Software"), to deal in the Software without restriction, including 74 without limitation the rights to use, copy, modify, merge, publish, 75 distribute, sublicense, and/or sell copies of the Software, and to 76 permit persons to whom the Software is furnished to do so, subject to 77 the following conditions: 78 79 The above copyright notice and this permission notice shall be 80 included in all copies or substantial portions of the Software. 81 82 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 83 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 84 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 85 IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 86 CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 87 TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 88 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 89 90 91 Credits 92 ******* 93 94 Keith Packard wrote the pcf driver found in XFree86. His work is at 95 the same time the specification and the sample implementation of the 96 PCF format. Undoubtedly, this driver is inspired from his work. 97
