Mercurial > sdl-ios-xcode
view include/SDL_mutex.h @ 1259:36f24cdfcda7
te: Thu, 17 Apr 2003 11:25:26 -0700
From: "Jim"
Subject: [SDL] Frame buffer patches...
Would seem that GCC 3.2.2 promotes all signed values to unsigned if any single vlaue is unsigned in an expression...
for instance when calculating an elo touch position....evertyhign is an (int) except for cach_vinfo.xres which is unsigned. THerefore if y
ou reverse the SDL_ELO_MIN_X and SDL_ELO_MAX_X values the resulging negative value pegs the expression to it's max. Attached it the accumu
lated patch to typecast the unsigned values to (int)
- *dx = (cache_vinfo.xres - (cache_vinfo.xres * (input_x - ELO_MIN_X)) / width);
+ *dx = ((int)cache_vinfo.xres - ((int)cache_vinfo.xres * (input_x - ELO_MIN_X)) / width);
and also to provide quite failure to operations which have the screen currently locked...
The touch screen I'm using the original values were exactly opposite of any position I touched on the screen - evaluating the math the expr
ession SHOULD have handled reversing the min and max values - and after casting the unsigned .xres and .yres to a signed int - worked well.
..
Jim
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 24 Jan 2006 06:36:43 +0000 |
parents | b8d311d90021 |
children | 3bdcef7e1c90 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library 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 Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Sam Lantinga slouken@libsdl.org */ #ifdef SAVE_RCSID static char rcsid = "@(#) $Id$"; #endif #ifndef _SDL_mutex_h #define _SDL_mutex_h /* Functions to provide thread synchronization primitives These are independent of the other SDL routines. */ #include "SDL_main.h" #include "SDL_types.h" #include "begin_code.h" /* Set up for C function definitions, even when using C++ */ #ifdef __cplusplus extern "C" { #endif /* Synchronization functions which can time out return this value if they time out. */ #define SDL_MUTEX_TIMEDOUT 1 /* This is the timeout value which corresponds to never time out */ #define SDL_MUTEX_MAXWAIT (~(Uint32)0) /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* Mutex functions */ /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* The SDL mutex structure, defined in SDL_mutex.c */ struct SDL_mutex; typedef struct SDL_mutex SDL_mutex; /* Create a mutex, initialized unlocked */ extern DECLSPEC SDL_mutex * SDLCALL SDL_CreateMutex(void); /* Lock the mutex (Returns 0, or -1 on error) */ #define SDL_LockMutex(m) SDL_mutexP(m) extern DECLSPEC int SDLCALL SDL_mutexP(SDL_mutex *mutex); /* Unlock the mutex (Returns 0, or -1 on error) It is an error to unlock a mutex that has not been locked by the current thread, and doing so results in undefined behavior. */ #define SDL_UnlockMutex(m) SDL_mutexV(m) extern DECLSPEC int SDLCALL SDL_mutexV(SDL_mutex *mutex); /* Destroy a mutex */ extern DECLSPEC void SDLCALL SDL_DestroyMutex(SDL_mutex *mutex); /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* Semaphore functions */ /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* The SDL semaphore structure, defined in SDL_sem.c */ struct SDL_semaphore; typedef struct SDL_semaphore SDL_sem; /* Create a semaphore, initialized with value, returns NULL on failure. */ extern DECLSPEC SDL_sem * SDLCALL SDL_CreateSemaphore(Uint32 initial_value); /* Destroy a semaphore */ extern DECLSPEC void SDLCALL SDL_DestroySemaphore(SDL_sem *sem); /* This function suspends the calling thread until the semaphore pointed * to by sem has a positive count. It then atomically decreases the semaphore * count. */ extern DECLSPEC int SDLCALL SDL_SemWait(SDL_sem *sem); /* Non-blocking variant of SDL_SemWait(), returns 0 if the wait succeeds, SDL_MUTEX_TIMEDOUT if the wait would block, and -1 on error. */ extern DECLSPEC int SDLCALL SDL_SemTryWait(SDL_sem *sem); /* Variant of SDL_SemWait() with a timeout in milliseconds, returns 0 if the wait succeeds, SDL_MUTEX_TIMEDOUT if the wait does not succeed in the allotted time, and -1 on error. On some platforms this function is implemented by looping with a delay of 1 ms, and so should be avoided if possible. */ extern DECLSPEC int SDLCALL SDL_SemWaitTimeout(SDL_sem *sem, Uint32 ms); /* Atomically increases the semaphore's count (not blocking), returns 0, or -1 on error. */ extern DECLSPEC int SDLCALL SDL_SemPost(SDL_sem *sem); /* Returns the current count of the semaphore */ extern DECLSPEC Uint32 SDLCALL SDL_SemValue(SDL_sem *sem); /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* Condition variable functions */ /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* The SDL condition variable structure, defined in SDL_cond.c */ struct SDL_cond; typedef struct SDL_cond SDL_cond; /* Create a condition variable */ extern DECLSPEC SDL_cond * SDLCALL SDL_CreateCond(void); /* Destroy a condition variable */ extern DECLSPEC void SDLCALL SDL_DestroyCond(SDL_cond *cond); /* Restart one of the threads that are waiting on the condition variable, returns 0 or -1 on error. */ extern DECLSPEC int SDLCALL SDL_CondSignal(SDL_cond *cond); /* Restart all threads that are waiting on the condition variable, returns 0 or -1 on error. */ extern DECLSPEC int SDLCALL SDL_CondBroadcast(SDL_cond *cond); /* Wait on the condition variable, unlocking the provided mutex. The mutex must be locked before entering this function! Returns 0 when it is signaled, or -1 on error. */ extern DECLSPEC int SDLCALL SDL_CondWait(SDL_cond *cond, SDL_mutex *mut); /* Waits for at most 'ms' milliseconds, and returns 0 if the condition variable is signaled, SDL_MUTEX_TIMEDOUT if the condition is not signaled in the allotted time, and -1 on error. On some platforms this function is implemented by looping with a delay of 1 ms, and so should be avoided if possible. */ extern DECLSPEC int SDLCALL SDL_CondWaitTimeout(SDL_cond *cond, SDL_mutex *mutex, Uint32 ms); /* Ends C function definitions when using C++ */ #ifdef __cplusplus } #endif #include "close_code.h" #endif /* _SDL_mutex_h */