gtk2/gdk/win32/gdkwin32keys.h
Руслан Ижбулатов 5e6c1928b4 W32: Prefer the deadkey combinations that the OS uses
Pick the W32 API for possible deadkey+<something> combinations
and prefer these to other sources of deadkey combos.
Specifically, if W32 API supports at least one combo for a particular
deadkey, only use that data and do not attempt to do other, unsupported
combinations, even if they make sense otherwise.
This is needed to, for example, correctly support US-International
keyboard layout, which produces a combined character for <' + a>
combo, but not for <' + s>, for example.

This is achieved by stashing all the deadkeys that we find in
an array, then doing extra loop through all virtual key codes and
trying to combine them with each of these deadkeys. Any combinations
that produce a single character are cached for later use.

In GTK Simple IM context, call a new GDK W32 function to do a lookup
on that cached combination table early on, among the "special cases"
(which are now partially obsolete).

A limitation of this code is that combinations with more than
one deadkey are not supported, except for combinations that consist
entirely of 2 known deadkeys. The upshot is that lookups should
be relatively fast, as deadkey array stays small and the combination
tree stays shallow.

Note that the use of ToUnicodeEx() seems suboptimal, as it should
be possible to just load a keyboard library (KBD*.DLL) manually
and obtain and use its key table directly. However, that is much more
complicated and would result in a significant rewrite of gdkkeys-win32.
The code from this commit, though hacky, is a direct addition to
existing code and should cover vast majority of the use-cases.

https://bugzilla.gnome.org/show_bug.cgi?id=569581
2016-08-04 16:37:19 +00:00

74 lines
2.9 KiB
C

/* GDK - The GIMP Drawing Kit
* Copyright (C) 2010 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __GDK_WIN32_KEYS_H__
#define __GDK_WIN32_KEYS_H__
#if !defined (__GDKWIN32_H_INSIDE__) && !defined (GDK_COMPILATION)
#error "Only <gdk/gdkwin32.h> can be included directly."
#endif
#include <gdk/gdk.h>
G_BEGIN_DECLS
/**
* GdkWin32KeymapMatch:
* @GDK_WIN32_KEYMAP_MATCH_NONE: no matches found. Output is not valid.
* @GDK_WIN32_KEYMAP_MATCH_INCOMPLETE: the sequence matches so far, but is incomplete. Output is not valid.
* @GDK_WIN32_KEYMAP_MATCH_PARTIAL: the sequence matches up to the last key,
* which does not match. Output is valid.
* @GDK_WIN32_KEYMAP_MATCH_EXACT: the sequence matches exactly. Output is valid.
*
* An enumeration describing the result of a deadkey combination matching.
*/
typedef enum
{
GDK_WIN32_KEYMAP_MATCH_NONE,
GDK_WIN32_KEYMAP_MATCH_INCOMPLETE,
GDK_WIN32_KEYMAP_MATCH_PARTIAL,
GDK_WIN32_KEYMAP_MATCH_EXACT
} GdkWin32KeymapMatch;
#ifdef GDK_COMPILATION
typedef struct _GdkWin32Keymap GdkWin32Keymap;
#else
typedef GdkKeymap GdkWin32Keymap;
#endif
typedef struct _GdkWin32KeymapClass GdkWin32KeymapClass;
#define GDK_TYPE_WIN32_KEYMAP (gdk_win32_keymap_get_type())
#define GDK_WIN32_KEYMAP(object) (G_TYPE_CHECK_INSTANCE_CAST ((object), GDK_TYPE_WIN32_KEYMAP, GdkWin32Keymap))
#define GDK_WIN32_KEYMAP_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GDK_TYPE_WIN32_KEYMAP, GdkWin32KeymapClass))
#define GDK_IS_WIN32_KEYMAP(object) (G_TYPE_CHECK_INSTANCE_TYPE ((object), GDK_TYPE_WIN32_KEYMAP))
#define GDK_IS_WIN32_KEYMAP_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GDK_TYPE_WIN32_KEYMAP))
#define GDK_WIN32_KEYMAP_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GDK_TYPE_WIN32_KEYMAP, GdkWin32KeymapClass))
GDK_AVAILABLE_IN_ALL
GType gdk_win32_keymap_get_type (void);
GDK_AVAILABLE_IN_3_20
GdkWin32KeymapMatch gdk_win32_keymap_check_compose (GdkWin32Keymap *keymap,
guint16 *compose_buffer,
gsize compose_buffer_len,
guint16 *output,
gsize *output_len);
G_END_DECLS
#endif /* __GDK_WIN32_KEYMAP_H__ */