Initial check in of some code under development.

1 files changed, 74 insertions, 0 deletions

diff --git a/console/dynafont.h b/console/dynafont.h
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+/* dynafont.h - Interfaces for the dynamic font handling.
+   Copyright (C) 2002 Free Software Foundation, Inc.
+   Written by Marcus Brinkmann.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd 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 2, or (at
+   your option) any later version.
+
+   The GNU Hurd 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 this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA. */
+
+#include <wchar.h>
+
+#include "bdf.h"
+
+
+/* The dynafont interface does not do locking on its own, for maximum
+   efficiency it relies on locking by the caller (because usually the
+   caller has some other data structures to lock along with the
+   dynafont.  However, it is safe to call two functions on different
+   dynafonts asynchronously.  */
+typedef struct dynafont *dynafont_t;
+
+/* Some glyphs are always available at a fixed location.  This
+   includes the representation for the unknown glyph and the blank.
+   Conveniently, the blank is located at its position in ASCII.  */
+#define FONT_INDEX_UNKNOWN 0
+#define FONT_INDEX_SPACE 32
+
+/* Create a new dynafont object, which uses glyphs from the font FONT
+   (which must be 8 pixels wide and up to 32 pixels heigh).  SIZE is
+   either 256 or 512, and specifies the number of available glyphs in
+   the font cache.  The object is returned in DYNAFONT.  The caller
+   must ensure the integrity of FONT until the object is destroyed or
+   the font is changed with dynafont_change_font.  */
+error_t dynafont_new (bdf_font_t font, int size, dynafont_t *dynafont);
+
+/* Release a dynafont object and its associated resources.  */ 
+void dynafont_free (dynafont_t df);
+
+/* Look up the vga font index for an UCS-4 character.  If not already
+   mapped, try to find space for a new entry and add the mapping.
+   Acquires an additional reference to the character.  Might return
+   the glyph for the unrepresentable character if the glyph is ot
+   available for this character or no free slot is available right
+   now.  In the former case, some information gets lost (to do
+   otherwise, one would have to either assign one of the scarce font
+   indices to each undisplayable character value on screen, or to
+   store the whole scrollback buffer as wide chars as well to recover
+   the lost info from that copy of the original text.  */
+int dynafont_lookup (dynafont_t df, wchar_t wide_chr);
+
+/* Release a reference to the glyph VGA_FONT_INDEX in dynafont DF.  */
+void dynafont_release (dynafont_t df, int vga_font_index);
+
+/* Load the VGA font to the card and make it active.  */
+void dynafont_activate (dynafont_t df);
+
+/* Change the font used by dynafont DF to FONT.  This transformation
+   is initially loss-less, if the new font can't display some
+   characters on the screen, you can always go back to a font that
+   does and get the glyphs for those characters back.  (However, the
+   comments in dynafont_lookup hold for glyphs looked up after the font
+   change.)  */
+void dynafont_change_font (dynafont_t df, bdf_font_t font);