Mercurial > sdl-ios-xcode
annotate src/thread/os2/SDL_syssem.c @ 4167:a6f635e5eaa6 SDL-1.2
Fixed bug #611
From Tim Angus 2008-08-12 11:18:06
I'm one of the maintainers of ioquake3.org, an updated version of the
Quake 3 engine. Relatively recently, we moved ioq3 to use SDL as a
replacement for 95% of the platform specific code that was there. On the
whole it's doing a great job but unfortunately since the move we've been
getting complaints about the quality of the mouse input on the Windows
platform to the point where for many the game is unplayable. Put in
other terms, the current stable SDL 1.2 is basically not fit for purpose
if you need high quality mouse input as you do in a first person shooter.
Over the weekend I decided to pull my finger out and actually figure out
what's going on. There are basically two major problems. Firstly, when
using the "windib" driver, mouse input is gathered via the WM_MOUSEMOVE
message. Googling for this indicates that often this is known to result
in "spurious" and/or "missing" mouse movement events; this is the
primary cause of the poor mouse input. The second problem is that the
"directx" driver does not work at all in combination with OpenGL meaning
that you can't use DirectInput if your application also uses OpenGL. In
other words you're locked into using the "windib" driver and its poor
mouse input.
In order to address these problems I've done the following:
* Remove WM_MOUSEMOVE based motion event generation and replace with
calls to GetCursorPos which seems much more reliable. In order to
achieve this I've moved mouse motion out into a separate function that
is called once per DIB_PumpEvents.
* Remove the restriction on the "directx" driver being inoperable in
combination with OpenGL. There is a bug for this issues that I've
hijacked to a certain extent
(http://bugzilla.libsdl.org/show_bug.cgi?id=265). I'm the first to admit
I don't really understand why this restriction is there in the first
place. The commit message for the bug fix that introduced this
restriction (r581) isn't very elaborate and I couldn't see any other bug
tracking the issue. If anyone has more information on the bug that was
avoided by r581 it would be helpful as I/someone could then look into
addressing the problem without disabling the "directx" driver.
* I've also removed the restriction on not being allowed to use
DirectInput in windowed mode. I couldn't see any reason for this, at
least not from our perspective. I have my suspicions that it'll be
something like matching up the cursor with the mouse coordinates...
* I bumped up the DirectInput API used to version 7 in order to get
access to mouse buttons 4-7. I've had to inject a little bit of the DX7
headers into SDL there as the MinGW ones aren't up to date in this respect.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Thu, 02 Apr 2009 04:43:36 +0000 |
| parents | a1b03ba2fcd0 |
| children |
| rev | line source |
|---|---|
| 1190 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
| 4159 | 3 Copyright (C) 1997-2009 Sam Lantinga |
| 1190 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
|
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|
6 modify it under the terms of the GNU Lesser General Public |
| 1190 | 7 License as published by the Free Software Foundation; either |
|
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Sam Lantinga <slouken@libsdl.org>
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|
8 version 2.1 of the License, or (at your option) any later version. |
| 1190 | 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 | |
|
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Sam Lantinga <slouken@libsdl.org>
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13 Lesser General Public License for more details. |
| 1190 | 14 |
|
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Updated copyright information and removed rcs id lines (problematic in branch merges)
Sam Lantinga <slouken@libsdl.org>
parents:
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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:
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diff
changeset
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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:
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changeset
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17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 1190 | 18 |
| 19 Sam Lantinga | |
| 20 slouken@libsdl.org | |
| 21 */ | |
|
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Use consistent identifiers for the various platforms we support.
Sam Lantinga <slouken@libsdl.org>
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22 #include "SDL_config.h" |
| 1190 | 23 |
| 24 /* Semaphore functions using the OS/2 API */ | |
| 25 | |
| 26 #define INCL_DOS | |
| 27 #define INCL_DOSERRORS | |
| 28 #define INCL_DOSSEMAPHORES | |
| 29 #include <os2.h> | |
| 30 | |
| 31 #include "SDL_thread.h" | |
| 32 #include "SDL_timer.h" | |
| 33 | |
| 34 | |
| 35 struct SDL_semaphore { | |
| 36 HMTX id; | |
| 37 HEV changed; | |
| 38 Uint32 value; | |
| 39 }; | |
| 40 | |
| 41 | |
| 42 /* Create a semaphore */ | |
| 43 DECLSPEC SDL_sem * SDLCALL SDL_CreateSemaphore(Uint32 initial_value) | |
| 44 { | |
| 45 SDL_sem *sem; | |
| 46 ULONG ulrc; | |
| 47 | |
| 48 /* Allocate sem memory */ | |
|
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49 sem = (SDL_sem *)SDL_malloc(sizeof(*sem)); |
| 1190 | 50 if ( sem ) { |
| 51 /* Create the mutex semaphore */ | |
| 52 ulrc = DosCreateMutexSem(NULL,&(sem->id),0,TRUE); | |
| 53 if ( ulrc ) { | |
| 54 SDL_SetError("Couldn't create semaphore"); | |
|
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parents:
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changeset
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55 SDL_free(sem); |
| 1190 | 56 sem = NULL; |
| 57 } else | |
| 58 { | |
| 59 DosCreateEventSem(NULL, &(sem->changed), 0, FALSE); | |
| 60 sem->value = initial_value; | |
| 61 DosReleaseMutexSem(sem->id); | |
| 62 } | |
| 63 } else { | |
| 64 SDL_OutOfMemory(); | |
| 65 } | |
| 66 return(sem); | |
| 67 } | |
| 68 | |
| 69 /* Free the semaphore */ | |
| 70 DECLSPEC void SDLCALL SDL_DestroySemaphore(SDL_sem *sem) | |
| 71 { | |
| 72 if ( sem ) { | |
| 73 if ( sem->id ) { | |
| 74 DosCloseEventSem(sem->changed); | |
| 75 DosCloseMutexSem(sem->id); | |
| 76 sem->id = 0; | |
| 77 } | |
|
1336
3692456e7b0f
Use SDL_ prefixed versions of C library functions.
Sam Lantinga <slouken@libsdl.org>
parents:
1312
diff
changeset
|
78 SDL_free(sem); |
| 1190 | 79 } |
| 80 } | |
| 81 | |
| 82 DECLSPEC int SDLCALL SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) | |
| 83 { | |
| 84 ULONG ulrc; | |
| 85 | |
| 86 if ( ! sem ) { | |
| 87 SDL_SetError("Passed a NULL sem"); | |
| 88 return -1; | |
| 89 } | |
| 90 | |
| 91 if ( timeout == SDL_MUTEX_MAXWAIT ) { | |
| 92 while (1) { | |
| 93 ulrc = DosRequestMutexSem(sem->id, SEM_INDEFINITE_WAIT); | |
| 94 if (ulrc) { | |
| 95 /* if error waiting mutex */ | |
| 96 SDL_SetError("DosRequestMutexSem() failed"); | |
| 97 return -1; | |
| 98 } else if (sem->value) { | |
| 99 sem->value--; | |
| 100 DosReleaseMutexSem(sem->id); | |
| 101 return 0; | |
| 102 } else { | |
| 103 ULONG ulPostCount; | |
| 104 DosResetEventSem(sem->changed, &ulPostCount); | |
| 105 DosReleaseMutexSem(sem->id); | |
| 106 /* continue waiting until somebody posts the semaphore */ | |
| 107 DosWaitEventSem(sem->changed, SEM_INDEFINITE_WAIT); | |
| 108 } | |
| 109 } | |
| 110 } else | |
| 111 if ( timeout == 0 ) | |
| 112 { | |
| 113 ulrc = DosRequestMutexSem(sem->id, SEM_INDEFINITE_WAIT); | |
| 114 if (ulrc==NO_ERROR) | |
| 115 { | |
| 116 if (sem->value) | |
| 117 { | |
| 118 sem->value--; | |
| 119 DosReleaseMutexSem(sem->id); | |
| 120 return 0; | |
| 121 } else | |
| 122 { | |
| 123 DosReleaseMutexSem(sem->id); | |
| 124 return SDL_MUTEX_TIMEDOUT; | |
| 125 } | |
| 126 } else | |
| 127 { | |
| 128 SDL_SetError("DosRequestMutexSem() failed"); | |
| 129 return -1; | |
| 130 } | |
| 131 } else { | |
| 132 ulrc = DosRequestMutexSem(sem->id, SEM_INDEFINITE_WAIT); | |
| 133 if (ulrc) { | |
| 134 /* if error waiting mutex */ | |
| 135 SDL_SetError("DosRequestMutexSem() failed"); | |
| 136 return -1; | |
| 137 } else | |
| 138 if (sem->value) { | |
| 139 sem->value--; | |
| 140 DosReleaseMutexSem(sem->id); | |
| 141 return 0; | |
| 142 } else { | |
| 143 ULONG ulPostCount; | |
| 144 DosResetEventSem(sem->changed, &ulPostCount); | |
| 145 DosReleaseMutexSem(sem->id); | |
| 146 /* continue waiting until somebody posts the semaphore */ | |
| 147 ulrc = DosWaitEventSem(sem->changed, timeout); | |
| 148 if (ulrc==NO_ERROR) | |
| 149 return 0; | |
| 150 else | |
| 151 return SDL_MUTEX_TIMEDOUT; | |
| 152 } | |
| 153 } | |
| 154 /* never reached */ | |
| 155 return -1; | |
| 156 } | |
| 157 | |
| 158 DECLSPEC int SDLCALL SDL_SemTryWait(SDL_sem *sem) | |
| 159 { | |
| 160 return SDL_SemWaitTimeout(sem, 0); | |
| 161 } | |
| 162 | |
| 163 DECLSPEC int SDLCALL SDL_SemWait(SDL_sem *sem) | |
| 164 { | |
| 165 return SDL_SemWaitTimeout(sem, SDL_MUTEX_MAXWAIT); | |
| 166 } | |
| 167 | |
| 168 /* Returns the current count of the semaphore */ | |
| 169 DECLSPEC Uint32 SDLCALL SDL_SemValue(SDL_sem *sem) | |
| 170 { | |
| 171 if ( ! sem ) { | |
| 172 SDL_SetError("Passed a NULL sem"); | |
| 173 return 0; | |
| 174 } | |
| 175 return sem->value; | |
| 176 } | |
| 177 | |
| 178 DECLSPEC int SDLCALL SDL_SemPost(SDL_sem *sem) | |
| 179 { | |
| 180 if ( ! sem ) { | |
| 181 SDL_SetError("Passed a NULL sem"); | |
| 182 return -1; | |
| 183 } | |
| 184 if ( DosRequestMutexSem(sem->id,SEM_INDEFINITE_WAIT) ) { | |
| 185 SDL_SetError("DosRequestMutexSem() failed"); | |
| 186 return -1; | |
| 187 } | |
| 188 sem->value++; | |
| 189 DosPostEventSem(sem->changed); | |
| 190 DosReleaseMutexSem(sem->id); | |
| 191 return 0; | |
| 192 } |