From 7b52cc13af4e85f1ca2deb6b6c77de9c95ea0dcf Mon Sep 17 00:00:00 2001 From: scuri Date: Fri, 17 Oct 2008 06:10:33 +0000 Subject: First commit - moving from LuaForge to SourceForge --- src/freetype2/pcf/README | 114 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 src/freetype2/pcf/README (limited to 'src/freetype2/pcf/README') diff --git a/src/freetype2/pcf/README b/src/freetype2/pcf/README new file mode 100644 index 0000000..cc1480b --- /dev/null +++ b/src/freetype2/pcf/README @@ -0,0 +1,114 @@ + FreeType font driver for PCF fonts + + Francesco Zappa Nardelli + + + +Introduction +************ + +PCF (Portable Compiled Format) is a binary bitmap font format, largely used +in X world. This code implements a PCF driver for the FreeType library. +Glyph images are loaded into memory only on demand, thus leading to a small +memory footprint. + +Information on the PCF font format can only be worked out from +`pcfread.c', and `pcfwrite.c', to be found, for instance, in the XFree86 +(www.xfree86.org) source tree (xc/lib/font/bitmap/). + +Many good bitmap fonts in bdf format come with XFree86: they can be +compiled into the pcf format using the `bdftopcf' utility. + + +Supported hardware +****************** + +The driver has been tested on linux/x86 and sunos5.5/sparc. In both +cases the compiler was gcc. When back in Paris, I will test it also +on linux/alpha. + + +Encodings +********* + +The variety of encodings that accompanies pcf fonts appears to encompass the +small set defined in freetype.h. On the other hand, each pcf font defines +two properties that specify encoding and registry. + +I decided to make these two properties directly accessible, leaving to the +client application the work of interpreting them. For instance: + + #include "pcftypes.h" /* include/freetype/internal/pcftypes.h */ + + FT_Face face; + PCF_Public_Face pcfface; + + FT_New_Face( library,..., &face ); + + pcfface = (PCF_Public_Face)face; + + if ((pcfface->charset_registry == "ISO10646") && + (pcfface->charset_encoding) == "1")) [..] + +Thus the driver always export `ft_encoding_none' as +face->charmap.encoding. FT_Get_Char_Index() behavior is unmodified, that +is, it converts the ULong value given as argument into the corresponding +glyph number. + + +Known problems +************** + +- dealing explicitly with encodings breaks the uniformity of freetype2 + api. + +- except for encodings properties, client applications have no + visibility of the PCF_Face object. This means that applications + cannot directly access font tables and are obliged to trust + FreeType. + +- currently, glyph names and ink_metrics are ignored. + +I plan to give full visibility of the PCF_Face object in the next +release of the driver, thus implementing also glyph names and +ink_metrics. + +- height is defined as (ascent - descent). Is this correct? + +- if unable to read size information from the font, PCF_Init_Face + sets available_size->width and available_size->height to 12. + +- too many english grammar errors in the readme file :-( + + +License +******* + +Copyright (C) 2000 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. + + +Credits +******* + +Keith Packard wrote the pcf driver found in XFree86. His work is at +the same time the specification and the sample implementation of the +PCF format. Undoubtedly, this driver is inspired from his work. -- cgit v1.2.3