/**
* @brief Initializes the sound subsystem.
*
* @return 0 on success.
*/
int sound_al_init (void)
{
int ret;
const ALchar* dev;
ALuint s;
ALint freq;
ALint attribs[4] = { 0, 0, 0, 0 };
/* Default values. */
ret = 0;
/* we'll need a mutex */
sound_lock = SDL_CreateMutex();
soundLock();
/* Get the sound device. */
dev = alcGetString( NULL, ALC_DEFAULT_DEVICE_SPECIFIER );
/* opening the default device */
al_device = alcOpenDevice(NULL);
if (al_device == NULL) {
WARN("Unable to open default sound device");
ret = -1;
goto snderr_dev;
}
/* Query EFX extension. */
if (conf.al_efx) {
al_info.efx = alcIsExtensionPresent( al_device, "ALC_EXT_EFX" );
if (al_info.efx == AL_TRUE) {
attribs[0] = ALC_MAX_AUXILIARY_SENDS;
attribs[1] = 4;
}
}
else
al_info.efx = AL_FALSE;
/* Create the OpenAL context */
al_context = alcCreateContext( al_device, attribs );
if (sound_lock == NULL) {
WARN("Unable to create OpenAL context");
ret = -2;
goto snderr_ctx;
}
/* Clear the errors */
alGetError();
/* Set active context */
if (alcMakeContextCurrent( al_context )==AL_FALSE) {
WARN("Failure to set default context");
ret = -4;
goto snderr_act;
}
/* Get context information. */
alcGetIntegerv( al_device, ALC_FREQUENCY, sizeof(freq), &freq );
/* Try to enable EFX. */
if (al_info.efx == AL_TRUE)
al_enableEFX();
else {
al_info.efx_reverb = AL_FALSE;
al_info.efx_echo = AL_FALSE;
}
/* Allocate source for music. */
alGenSources( 1, &music_source );
/* Check for errors. */
al_checkErr();
/* Start allocating the sources - music has already taken his */
source_nstack = 0;
source_mstack = 0;
while (source_nstack < SOUND_MAX_SOURCES) {
if (source_mstack < source_nstack+1) { /* allocate more memory */
source_mstack += 32;
source_stack = realloc( source_stack, sizeof(ALuint) * source_mstack );
}
alGenSources( 1, &s );
source_stack[source_nstack] = s;
/* Distance model defaults. */
alSourcef( s, AL_MAX_DISTANCE, 5000. );
alSourcef( s, AL_ROLLOFF_FACTOR, 1. );
alSourcef( s, AL_REFERENCE_DISTANCE, 500. );
/* Set the filter. */
if (al_info.efx == AL_TRUE)
alSource3i( s, AL_AUXILIARY_SEND_FILTER, efx_directSlot, 0, AL_FILTER_NULL );
/* Check for error. */
if (alGetError() == AL_NO_ERROR)
source_nstack++;
else
break;
}
/* Reduce ram usage. */
source_mstack = source_nstack;
source_stack = realloc( source_stack, sizeof(ALuint) * source_mstack );
/* Copy allocated sources to total stack. */
source_ntotal = source_mstack;
source_total = malloc( sizeof(ALuint) * source_mstack );
memcpy( source_total, source_stack, sizeof(ALuint) * source_mstack );
/* Copy allocated sources to all stack. */
source_nall = source_mstack;
source_all = malloc( sizeof(ALuint) * source_mstack );
memcpy( source_all, source_stack, sizeof(ALuint) * source_mstack );
/* Set up how sound works. */
alDistanceModel( AL_INVERSE_DISTANCE_CLAMPED );
alDopplerFactor( 1. );
sound_al_env( SOUND_ENV_NORMAL, 0. );
/* Check for errors. */
al_checkErr();
/* we can unlock now */
soundUnlock();
/* debug magic */
DEBUG("OpenAL started: %d Hz", freq);
DEBUG("Renderer: %s", alGetString(AL_RENDERER));
if (al_info.efx == AL_FALSE)
DEBUG("Version: %s without EFX", alGetString(AL_VERSION));
else
DEBUG("Version: %s with EFX %d.%d", alGetString(AL_VERSION),
al_info.efx_major, al_info.efx_minor);
DEBUG();
return 0;
/*
* error handling
*/
snderr_act:
alcDestroyContext( al_context );
snderr_ctx:
al_context = NULL;
alcCloseDevice( al_device );
snderr_dev:
al_device = NULL;
soundUnlock();
SDL_DestroyMutex( sound_lock );
sound_lock = NULL;
return ret;
}
/**
* @brief Initializes the sound subsystem.
*
* @return 0 on success.
*/
int sound_al_init (void)
{
int ret;
ALuint s;
ALint freq;
ALint attribs[4] = { 0, 0, 0, 0 };
/* Default values. */
ret = 0;
/* we'll need a mutex */
sound_lock = SDL_CreateMutex();
soundLock();
/* opening the default device */
al_device = alcOpenDevice(NULL);
if (al_device == NULL) {
WARN(_("Unable to open default sound device"));
ret = -1;
goto snderr_dev;
}
/* Query EFX extension. */
if (conf.al_efx) {
al_info.efx = alcIsExtensionPresent( al_device, "ALC_EXT_EFX" );
if (al_info.efx == AL_TRUE) {
attribs[0] = ALC_MAX_AUXILIARY_SENDS;
attribs[1] = 4;
}
}
else
al_info.efx = AL_FALSE;
/* Create the OpenAL context */
al_context = alcCreateContext( al_device, attribs );
if (al_context == NULL) {
WARN(_("Unable to create OpenAL context"));
ret = -2;
goto snderr_ctx;
}
/* Clear the errors */
alGetError();
/* Set active context */
if (alcMakeContextCurrent( al_context )==AL_FALSE) {
WARN(_("Failure to set default context"));
ret = -4;
goto snderr_act;
}
/* Get context information. */
alcGetIntegerv( al_device, ALC_FREQUENCY, sizeof(freq), &freq );
/* Try to enable EFX. */
if (al_info.efx == AL_TRUE)
al_enableEFX();
else {
al_info.efx_reverb = AL_FALSE;
al_info.efx_echo = AL_FALSE;
}
/* Allocate source for music. */
alGenSources( 1, &music_source );
/* Check for errors. */
al_checkErr();
/* Start allocating the sources - music has already taken his */
source_nstack = 0;
source_mstack = 0;
while (source_nstack < conf.snd_voices) {
if (source_mstack < source_nstack+1) { /* allocate more memory */
if (source_mstack == 0)
source_mstack = conf.snd_voices;
else
source_mstack *= 2;
source_stack = realloc( source_stack, sizeof(ALuint) * source_mstack );
}
alGenSources( 1, &s );
source_stack[source_nstack] = s;
/* How OpenAL distance model works:
*
* Clamped:
* gain = distance_function( CLAMP( AL_REFERENCE_DISTANCE, AL_MAX_DISTANCE, distance ) );
*
* Distance functions:
* AL_REFERENCE_DISTANCE
* * Inverse = ------------------------------------------------------------------------------
* AL_REFERENCE_DISTANCE + AL_ROLLOFF_FACTOR ( distance - AL_REFERENCE_DISTANCE )
*
* 1 - AL_ROLLOFF_FACTOR ( distance - AL_REFERENCE_DISTANCE )
* * Linear = ----------------------------------------------------------
* AL_MAX_DISTANCE - AL_REFERENCE_DISTANCE
*
* / distance \ -AL_ROLLOFF_FACTOR
* * Exponential = | --------------------- |
* \ AL_REFERENCE_DISTANCE /
*
*
* Some values:
*
* model falloff reference 100 1000 5000 10000
* linear 1 500 1.000 0.947 0.526 0.000
* inverse 1 500 1.000 0.500 0.100 0.050
* exponent 1 500 1.000 0.500 0.100 0.050
* inverse 0.5 500 1.000 0.667 0.182 0.095
* exponent 0.5 500 1.000 0.707 0.316 0.223
* inverse 2 500 1.000 0.333 0.052 0.026
* exponent 2 500 1.000 0.250 0.010 0.003
*/
alSourcef( s, AL_REFERENCE_DISTANCE, 500. ); /* Close distance to clamp at (doesn't get louder). */
alSourcef( s, AL_MAX_DISTANCE, 25000. ); /* Max distance to clamp at (doesn't get quieter). */
alSourcef( s, AL_ROLLOFF_FACTOR, 1. ); /* Determines how it drops off. */
/* Set the filter. */
if (al_info.efx == AL_TRUE)
alSource3i( s, AL_AUXILIARY_SEND_FILTER, efx_directSlot, 0, AL_FILTER_NULL );
/* Check for error. */
if (alGetError() == AL_NO_ERROR)
source_nstack++;
else
break;
}
/* Reduce ram usage. */
source_mstack = source_nstack;
source_stack = realloc( source_stack, sizeof(ALuint) * source_mstack );
/* Copy allocated sources to total stack. */
source_ntotal = source_mstack;
source_total = malloc( sizeof(ALuint) * source_mstack );
memcpy( source_total, source_stack, sizeof(ALuint) * source_mstack );
/* Copy allocated sources to all stack. */
source_nall = source_mstack;
source_all = malloc( sizeof(ALuint) * source_mstack );
memcpy( source_all, source_stack, sizeof(ALuint) * source_mstack );
/* Set up how sound works. */
alDistanceModel( AL_INVERSE_DISTANCE_CLAMPED ); /* Clamping is fundamental so it doesn't sound like crap. */
alDopplerFactor( 1. );
sound_al_env( SOUND_ENV_NORMAL, 0. );
/* Check for errors. */
al_checkErr();
/* we can unlock now */
soundUnlock();
/* debug magic */
DEBUG(_("OpenAL started: %d Hz"), freq);
DEBUG(_("Renderer: %s"), alGetString(AL_RENDERER));
if (al_info.efx == AL_FALSE)
DEBUG(_("Version: %s without EFX"), alGetString(AL_VERSION));
else
DEBUG(_("Version: %s with EFX %d.%d"), alGetString(AL_VERSION),
al_info.efx_major, al_info.efx_minor);
DEBUG("");
return ret;
/*
* error handling
*/
snderr_act:
alcDestroyContext( al_context );
snderr_ctx:
al_context = NULL;
alcCloseDevice( al_device );
snderr_dev:
al_device = NULL;
soundUnlock();
SDL_DestroyMutex( sound_lock );
sound_lock = NULL;
return ret;
}
