Mercurial > sdl-ios-xcode
annotate src/SDL_error_c.h @ 4384:6800e2560310 SDL-1.2
Fixed bugs #882 and 865, re-opening bug #634
Ronald Lamprecht to SDL
Hi,
Sam Lantinga wrote:
The problem with that fix is that it breaks IME events again. Maybe
we can handle keyboard events differently to prevent this issue?
Spending an hour reading MSDN, analysing SDL and another hour testing the reality on XP I am really wondering how patch r4990 could have ever worked in any situation. It's main effect is to break the unicode translation and causing spurious activation events!
Why does TranslateMessage(&msg) nothing useful? Simply because it does not affect "msg" at all! All keyboard events are dispatched without the slightest change (see MSDN). TranslateMessage() just appends additional WM_CHAR, WM_DEADCHAR, WM_SYSCHAR, WM_SYSDEADCHAR event messages to the queue. But I could not find any SDL event handling routine that catches these events and transforms them to proper SDL keyevents while eliminating the corresponding WM_KEYDOWN, etc. events. Thus any IME input like the '@' generated by "Alt + 6(Numpad) + 4(Numpad)" is simply lost.
But the situation is even worse! Up to r4990 the TranslateKey()/ToUnicode() calls did evaluate dead keys and did deliver proper key events for subsequent key strokes like '´' + 'e' resulting in 'é'. ToUnicode() needs proper key state informations to be able to handle these substitutions. But unfortunatly TranslateMessage() needs the same state information and eats it up while generating the WM_CHAR messages :-( Thus the current 1.2.14 breakes the partial IME support of previous releases, too.
The key state race condition between ToUnicode() and TranslateMessage() requires to avoid any ToUnicode() usage for receiving proper WM_CHAR, etc. messages generated by TranslateMessage(). (Yes - the '@' and 'é' appear as WM_CHAR messages when unicode is switched off).
The spurious SDL activation events are *not* caused by additional WM_ACTIVATE Windows messages! Besides DIB_HandleMessage() SDL_PrivateAppActive() is called by another source which I am not yet aware of - any hints?
Thus I do strongly recommend the deletion of the TranslateMessage(&msg) call as a quick fix.
A proper support of unicode and IME requires a clean SDL keyboard input concept first. Which SDL keyboards events should be transmitted to the app when the user presses '´' + 'e' ? Within the current unicode handling the first key stroke is hidden. Even though ToUnicode() delivers the proper key SDL does ignore it in TranslateKey(). Just the composed key event is transmitted to the app. That is what you expect for text input, but the app can no longer use keys like '^' as a key button because it will never receive a key event for it!
With a given concept it seems to be necessary to regenerate SDL key events out of the WM_CHAR, etc. events and to drop all related direct WM_KEYDOWN, etc. events while the remaining basic WM_KEYDOWN, etc. events would still have to result in SDL key events.
Anyway the source of the spurious WM_ACTIVATE should be located to avoid future trouble.
Greets,
Ronald
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 17 Nov 2009 04:59:13 +0000 |
parents | a1b03ba2fcd0 |
children |
rev | line source |
---|---|
0 | 1 /* |
2 SDL - Simple DirectMedia Layer | |
4159 | 3 Copyright (C) 1997-2009 Sam Lantinga |
0 | 4 |
5 This library is free software; you can redistribute it and/or | |
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
911
diff
changeset
|
6 modify it under the terms of the GNU Lesser General Public |
0 | 7 License as published by the Free Software Foundation; either |
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
911
diff
changeset
|
8 version 2.1 of the License, or (at your option) any later version. |
0 | 9 |
10 This library is distributed in the hope that it will be useful, | |
11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
911
diff
changeset
|
13 Lesser General Public License for more details. |
0 | 14 |
1312
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
911
diff
changeset
|
15 You should have received a copy of the GNU Lesser General Public |
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
911
diff
changeset
|
16 License along with this library; if not, write to the Free Software |
c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
911
diff
changeset
|
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
0 | 18 |
19 Sam Lantinga | |
252
e8157fcb3114
Updated the source with the correct e-mail address
Sam Lantinga <slouken@libsdl.org>
parents:
0
diff
changeset
|
20 slouken@libsdl.org |
0 | 21 */ |
1402
d910939febfa
Use consistent identifiers for the various platforms we support.
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
22 #include "SDL_config.h" |
0 | 23 |
24 /* This file defines a structure that carries language-independent | |
25 error messages | |
26 */ | |
27 | |
28 #ifndef _SDL_error_c_h | |
29 #define _SDL_error_c_h | |
30 | |
31 #define ERR_MAX_STRLEN 128 | |
32 #define ERR_MAX_ARGS 5 | |
33 | |
911
04a403e4ccf5
Date: Mon, 3 May 2004 03:15:01 +0100
Sam Lantinga <slouken@libsdl.org>
parents:
769
diff
changeset
|
34 typedef struct SDL_error { |
0 | 35 /* This is a numeric value corresponding to the current error */ |
36 int error; | |
37 | |
38 /* This is a key used to index into a language hashtable containing | |
39 internationalized versions of the SDL error messages. If the key | |
40 is not in the hashtable, or no hashtable is available, the key is | |
41 used directly as an error message format string. | |
42 */ | |
1824
e25445333ccf
Fixed signed/unsigned issues
Sam Lantinga <slouken@libsdl.org>
parents:
1402
diff
changeset
|
43 char key[ERR_MAX_STRLEN]; |
0 | 44 |
45 /* These are the arguments for the error functions */ | |
46 int argc; | |
47 union { | |
48 void *value_ptr; | |
49 #if 0 /* What is a character anyway? (UNICODE issues) */ | |
50 unsigned char value_c; | |
51 #endif | |
52 int value_i; | |
53 double value_f; | |
1824
e25445333ccf
Fixed signed/unsigned issues
Sam Lantinga <slouken@libsdl.org>
parents:
1402
diff
changeset
|
54 char buf[ERR_MAX_STRLEN]; |
0 | 55 } args[ERR_MAX_ARGS]; |
56 } SDL_error; | |
57 | |
58 #endif /* _SDL_error_c_h */ |