[Emacs-diffs] Changes to font-backend

[Glenn Morris]

CVSROOT:        /sources/emacs
Module name:    emacs
Changes by:     Glenn Morris <gm>       08/02/21 04:00:22

Index: font-backend
===================================================================
RCS file: font-backend
diff -N font-backend
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ font-backend        21 Feb 2008 04:00:22 -0000      1.1
@@ -0,0 +1,77 @@
+Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+  Free Software Foundation, Inc.
+See the end of the file for license conditions.
+
+
+New font handling mechanism with font backend method
+----------------------------------------------------
+
+The configure script, if invoked with "--enable-font-backend", checks
+if libraries freetype and fontconfig exist.  If they are both
+available, macro "USE_FONT_BACKEND" is defined in src/config.h.  In
+that case, the existence of Xft library is checked too.
+
+The new files are:
+       font.h -- header providing font-backend related structures
+               (most important ones are "struct font" and "struct
+               font_driver"), macros, and etc.
+       font.c -- main font handling code.
+       xfont.c -- font-driver on X for X core fonts.
+       ftfont.c -- generic font-driver for FreeType fonts providing
+               device-independent methods of struct font_driver.
+       xftfont.c -- font-driver on X using Xft for FreeType fonts
+               utilizing methods provided by ftfont.c.
+       ftxfont.c -- font-driver on X directly using FreeType fonts
+               utilizing methods provided by ftfont.c.
+       w32font.c -- font driver on w32 using Windows native fonts,
+               corresponding to xfont.c
+
+So we already have codes for X.  For the other systems (w32 and mac),
+it seems that we need these files:
+       atmfont.c -- font-driver on mac using ATM fonts, corresponding
+               to xfont.c
+As BDF fonts are currently used on w32, we may also implement these:
+       bdffont.c -- generic font-driver for BDF fonts, corresponding to
+               ftfont.c
+       bdfw32font.c -- font-driver on w32 using BDF fonts,
+               corresponding to ftxfont.c
+But, as FreeType already supports BDF fonts, if FreeType and
+Fontconfig are also available on w32, what we need may be:
+       ftw32font.c -- font-driver on w32 directly using FreeType fonts
+               utilizing methods provided by ftfont.c.
+
+And, for those to work, macterm.c and macfns.c must be changed by the
+similar way as xterm.c and xfns.c (the parts "#ifdef USE_FONT_BACKEND"
+... "#endif" should be checked).
+
+It may be interesting if Emacs supports a frame buffer directly and
+has these font driver.
+       ftfbfont.c -- font-driver on FB for FreeType fonts.
+       bdffbfont.c -- font-driver on FB for BDF fonts.
+
+Note: The fontset related codes are not yet matured to work well with
+the font backend method.  So, for instance, even if you start Emacs
+as something like this:
+  % emacs -fn tahoma
+Non-ASCII Latin characters will not be displayed by the font "tahoma".
+In such a case, please try this:
+
+(set-fontset-font "fontset-default" 'latin '("tahoma" . "unicode-bmp"))
+
+
+This file is part of GNU Emacs.
+
+GNU Emacs is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3, or (at your option)
+any later version.
+
+GNU Emacs is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Emacs; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA.