Mercurial > sdl-ios-xcode
view src/thread/pth/SDL_sysmutex.c @ 3496:78fc8ea578b2
Joe 2009-11-23 21:31:10 PST
If type is ::SDL_HAPTIC_CARTESIAN, direction is encoded by three positions
367 * (X axis, Y axis and Z axis (with 3 axes)). ::SDL_HAPTIC_CARTESIAN
uses
368 * the first three \c dir parameters. The cardinal directions would
be:
369 * - North: 0,-1, 0
370 * - East: -1, 0, 0
371 * - South: 0, 1, 0
372 * - West: 1, 0, 0
typedef struct SDL_HapticDirection
{
Uint8 type; /**< The type of encoding. */
Uint16 dir[3]; /**< The encoded direction. */
} SDL_HapticDirection;
An unsigned int can't store negative values and I don't see an alternate way to
encode them in the docs or source. The best I have been able to come up with is
using a negative magnitude for the effect but this will only get me 2 of the 4
quadrants in the plane for 2d effects. I looked at the win32 and linux
implementations and I believe is is safe to use signed ints in the direction
struct. I am unfamiliar with the darwin haptics API so I don't know if it is
safe.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Fri, 27 Nov 2009 19:29:27 +0000 |
parents | 99210400e8b9 |
children |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2009 Sam Lantinga 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 2.1 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, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" /* * GNU pth mutexes * * Patrice Mandin */ #include <pth.h> #include "SDL_mutex.h" #include "SDL_sysmutex_c.h" /* Create a mutex */ SDL_mutex * SDL_CreateMutex(void) { SDL_mutex *mutex; /* Allocate mutex memory */ mutex = (SDL_mutex *) SDL_malloc(sizeof(*mutex)); if (mutex) { /* Create the mutex, with initial value signaled */ if (!pth_mutex_init(&(mutex->mutexpth_p))) { SDL_SetError("Couldn't create mutex"); SDL_free(mutex); mutex = NULL; } } else { SDL_OutOfMemory(); } return (mutex); } /* Free the mutex */ void SDL_DestroyMutex(SDL_mutex * mutex) { if (mutex) { SDL_free(mutex); } } /* Lock the mutex */ int SDL_mutexP(SDL_mutex * mutex) { if (mutex == NULL) { SDL_SetError("Passed a NULL mutex"); return -1; } pth_mutex_acquire(&(mutex->mutexpth_p), FALSE, NULL); return (0); } /* Unlock the mutex */ int SDL_mutexV(SDL_mutex * mutex) { if (mutex == NULL) { SDL_SetError("Passed a NULL mutex"); return -1; } pth_mutex_release(&(mutex->mutexpth_p)); return (0); } /* vi: set ts=4 sw=4 expandtab: */