OpenAl Soundmanager         A very simple sound manager using OpenAL

SoundManager - A very simple sound manager using OpenAL

Aug 05 - First version of the code by Van Stokes, Jr. (http://www.EvilMasterMindsInc.com).

Sep 05 - Second version by Steven.

Aug 10 - Third version by Pillum.

Goals


Note: This code is written for the version '1.1' of OpenAL. Verify that your library is not 1.0. Check the OpenAL site for the new SDK installer.
However, several people couldn't integrate the 1.1 version with Ogre. Ogre simply segfaults but until now anybody could find the reason... If it happens, you should revert to the 1.0 version and make three small modifications to the source.

Please use this forum thread to discuss problems, suggestions, etc.

ToDo

  • test it on Linux and MacOS: anyone intersted?
  • make functions that call the EAX functions!

Compiling

  • Download and install the OpenAL library and the libvorbis and libogg libraries.
  • Include the "OpenAl_library\include" containing the directories AL.
  • Link to : OpenAL32.lib, libogg and libvorbis.
  • Adjust for your need the #define and #include of SoundManager.h
  • Be careful with MAX_AUDIO_BUFFERS and MAX_AUDIO_SOURCES.
  • You should replace all "printf" by your own version log message.


{FOOTNOTE}

Documentation

  • Create the object from the class with createManager()
  • Call the init() function
  • Call the loadDefaultSounds() function to PRE-LOAD audio into the buffers. This is optional. Review the function to make changes that you need.
  • Set the listener location by calling setListenerPosition() function - continually call this as your Listener (camera) position changes!
  • For each object that emits sound, call the loadSound() function. CAREFUL : The filename must be unique. Optional : For each object you can set the all the parameters of the sound with setSound() or only the position, velocity and direction with setSoundPosition().
  • Call the playAudioSource() to play the sound at some event. This function will play the sound and then stop. It will NOT repeat playing. Use stopAudioSource() to stop a sound from playing if its still playing.
  • Call pauseAudio() or pauseAllAudio() to pause one or all sound(s).
  • Call resumeAudio() or resumeAllAudio() to resume one or all paused sound.
  • When your object is done emitting sounds (when out of range for example) call releaseAudioSource(). It is important to release your source when you are no longer going to need it because you are limited in the number of sources you can have.
  • If your objects moves (other than the listener/camera) then continually update the objects position by calling setSourcePosition().


Note: To be able to hear the sound changing when the listener (or the object) moves, you need to use mono sound files. Stereo wav files suppress the spatialization effect. See the comment on the page 18 of the OpenAL_Programmers_Guide.pdf:

8-bit PCM data is expressed as an unsigned value over the range 0 to 255, 128 being an audio

output level of zero. 16-bit PCM data is expressed as a signed value over the range -32768 to

32767, 0 being an audio output level of zero. Stereo data is expressed in interleaved format,

left channel first. Buffers containing more than one channel of data will be played without 3D

spatialization.

Main.cpp

#include <iostream>
 #include "src/SoundManager.h"
 
 int main()
 {
   std::cout << "Simple Sound Manager test application !" << std::endl;
   
   SoundManager* soundMgr = SoundManager::createManager();
   
   std::cout << soundMgr->listAvailableDevices();
   
   soundMgr->init();
   
   soundMgr->setAudioPath( (char*) ".\\" );
   
   unsigned int audioId;
 
   // We loop to be able to test the pause function
   soundMgr->loadAudio( "test.ogg", &audioId, true);
 
 /*   
    // Set our LISTENER Location (i.e. the ears)
    // The listener is what hears the sounds emitted by audio sources.
    // Note: you only have ONE set of ears - i.e. there is only ONE listener.
    soundMgr->setListenerPosition( mPlayerSceneNode->getWorldPosition(),
        Ogre::Vector3::ZERO, mPlayerSceneNode->getOrientation() );
 
    // Set the Audio SOURCE location/position AND by default PLAY the audio.
    // Note how we reference the correct audio source by using 'mAudioSource'.
 
    soundMgr->setSound( audioId, mSomeObjectSceneNode->getWorldPosition(),
        Ogre::Vector3::ZERO, Ogre::Vector3::ZERO, 1000.0f, true, true, 1.0f );
 */
 
    // Play an Audio source - force a restart from the begining of the buffer.
    // That means, re-play the media file from the begining.
    soundMgr->playAudio( audioId, true );
 
    printf("Audio playing.  Type Enter.\n");
    getchar(); // To hear the sound until the end.
 
    soundMgr->pauseAudio( audioId );
 
    printf("Audio paused.  Type Enter.\n");
    getchar();
 
 //   soundMgr->resumeAudio( audioId );
    soundMgr->resumeAllAudio( );
 
    printf("Audio playing. Type Enter\n");
    getchar();
 
    // Force an audio source to stop playing.
    soundMgr->stopAudio( audioId );
    
   // Release an audio source when we are done with it.
   // This isn't required if you destruct the AudioEngine - as it cleans itself up.
   // But, you *SHOULD* do this when, for example, your SceneObject is no longer
   // in the scene for some reason. In other words, if you don't need this source
   // anymore then free up the resource. Remember, you are limited in audio sources.
   soundMgr->releaseAudio( audioId );
   
   delete soundMgr;
   
   return 0;
 }

SoundManager.h

/**
 *  SoundManager.h
 *
 *  Original Code : Van Stokes, Jr. (http://www.EvilMasterMindsInc.com) - Aug 05
 *  Modified Code : Steven Gay - mec3@bluewin.ch - Septembre 2005 - Jan 06
 *                  Deniz Sarikaya - daimler3@gmail.com - August 2010
 *
 *                    Partial Documentation
 *                    =====================
 *
 *  Very simple SoundManager using OpenAl. 
 *
 *  For a more complete one, you should see :
 *  OpenAL++ http://alpp.sourceforge.net/
 *
 ****************************************************************************
 *  COMPILE
 *
 *  - Don't forget to link to : ALut.lib and OpenAL32.lib.
 *    The order is important.
 *
 *  - With CodeBlocks there is one warning I didn't resolve :
 *     "Warning: .drectve `/DEFAULTLIB:"uuid.lib" /DEFAULTLIB:"uuid.lib" ' unrecognized"
 *
 ****************************************************************************
 *  USAGE
 *
 * 1. Create the object from the class with createManager()
 *
 * 2. Call the init() function
 *
 * 3. Call the loadDefaultSounds() function to PRE-LOAD audio into the buffers.
 *    This is optional. Review the function to make changes that you need.
 *
 * 4. Set the Listener Location by calling setListenerPosition() function
 *    continually call this as your Listener (camera) position changes!
 *
 * 5. For each object that emits sound, call the loadSound() function.
 *    CAREFUL : The filename must be unique.
 *
 * 6. Optional : For each object you can set the all the parameters of the
 *    sound with setSound() or only the position, velocity and direction with
 *    setSoundPosition().
 *
 * 7. Call the playAudioSource() to play the sound at some event.
 *    This function will play the sound and then stop. It will NOT repeat playing.
 *    Use stopAudioSource() to stop a sound from playing if its still playing
 *
 * 8. Call pauseAudio() or pauseAllAudio() to pause one or all sound(s).
 *    Call resumeAudio() or resumeAllAudio() to resume one or all paused sound(s).
 *
 * 9. When your object is done emitting sounds (when out of range for example)
 *    call releaseAudioSource().
 *    It is important to release your source when you are no longer going to
 *    need it because you are limited in the number of sources you can have.
 *
 * 10. If your objects moves (other than the listener/camera) then
 *    continually update the objects position by calling setSourcePosition().
 *
 ******************************************************************************
 * 
 * Additional informations :
 *
 * Ogg Vorbis - http://www.xiph.org/downloads/
 *            - http://www.illiminable.com/ogg/
 * Flac       - http://flac.sourceforge.net/features.html
 * Theora     - http://www.theora.org/
 *
 *
 ******************************************************************************
 *
 * TODO
 *
 * loadOGG()
 * alSourcePause()
 *
 * Use the EAX functions !
 *
 ******************************************************************************/
 
 #ifndef __SOUNDMANAGER_H__
 #define __SOUNDMANAGER_H__
 
 #include <stdio.h>
 #include <string>
 
 // Comment this line if you don't have the EAX 2.0 SDK installed
 //#define _USEEAX
 
 #ifdef _USEEAX
     #include "eax.h"
 #endif
 
 // OpenAl version 1.1
 #include <al.h>
 #include <alc.h>
 
 // Modify this as you need.
 #ifdef OGRE
    #include "OgreVector3.h"
    #include "OgreQuaternion.h"
    using namespace Ogre;
 #else
    #include "Vector3.h"
    using namespace gameengine::utilities;
 #endif
 
 // Be very careful with these two parameters
 // It is very dependant on the audio hardware your
 // user is using. It you get too large, it may work
 // on one persons system but not on another.
 // TODO Write a fct testing the hardware !
 #define MAX_AUDIO_BUFFERS   64
 #define MAX_AUDIO_SOURCES   16
 
 // Used to store sound filenames
 #define MAX_FILENAME_LENGTH 40
 
 class SoundManager
 {
   private:
        // EAX related
        bool isEAXPresent;
 #ifdef _USEEAX
        // EAX 2.0 GUIDs
        const GUID DSPROPSETID_EAX20_ListenerProperties
            = { 0x306a6a8, 0xb224, 0x11d2, { 0x99, 0xe5, 0x0, 0x0, 0xe8, 0xd8, 0xc7, 0x22 } };
       
        const GUID DSPROPSETID_EAX20_BufferProperties
            = { 0x306a6a7, 0xb224, 0x11d2, {0x99, 0xe5, 0x0, 0x0, 0xe8, 0xd8, 0xc7, 0x22 } };
       
        EAXSet eaxSet; // EAXSet function, retrieved if EAX Extension is supported
        EAXGet eaxGet; // EAXGet function, retrieved if EAX Extension is supported
 #endif // _USEEAX
       
        bool isInitialised;
        ALCdevice* mSoundDevice;
        ALCcontext* mSoundContext;
       
        std::string mAudioPath;
       
        bool isSoundOn;
 
        ALfloat position[3];
        ALfloat velocity[3];
        ALfloat orientation[6];
       
        // Needed because of hardware limitation
        // Audio sources
        unsigned int mAudioSourcesInUseCount;
        unsigned int mAudioSources[ MAX_AUDIO_SOURCES ];
        bool         mAudioSourceInUse[ MAX_AUDIO_SOURCES ];
       
        // Audio buffers
        unsigned int mAudioBuffersInUseCount;
        unsigned int mAudioBuffers[ MAX_AUDIO_BUFFERS ];
        bool         mAudioBufferInUse[ MAX_AUDIO_BUFFERS ];
        char         mAudioBufferFileName[ MAX_AUDIO_BUFFERS ][ MAX_FILENAME_LENGTH ];
   
        // Function to check if the soundFile is already loaded into a buffer
        int locateAudioBuffer( std::string filename );
        int loadAudioInToSystem( std::string filename );
        // TODO bool loadWAV( std::string filename, ALuint pDestAudioBuffer );
        bool loadOGG( std::string filename, ALuint pDestAudioBuffer );
        // TODO bool loadAU( std::string filename, ALuint pDestAudioBuffer );
       
    public:
        static SoundManager* mSoundManager;
       
        SoundManager( void );
        virtual ~SoundManager( void );
        void SoundManager::selfDestruct( void );
        static SoundManager* createManager( void );
        static SoundManager* getSingletonPtr( void ) { return mSoundManager; };
 
        bool init( void );
        bool getIsSoundOn( void ) { return isSoundOn; };
        void setAudioPath( char* path ) { mAudioPath = std::string( path ); };
       
        bool checkALError( void );
        bool checkALError( std::string pMsg );
       
        /** See http://www.openal.org/windows_enumeration.html for installing other
        *   devices. You should at least have "Generic Hardware".
        */
        std::string listAvailableDevices( void );
       
        // Aquire an Audio Source
        // filename = pass in the sound file to play for this source (ex. "myfile.wav")
        // audioId   = returns the AudioSource identifier you will need for the PlayAudioSource();
        bool loadAudio( std::string filename, unsigned int *audioId, bool loop );
        bool releaseAudio( unsigned int audioID );
       
        // Returns true if the audio is started from the beginning
        // false if error or if already playing
        bool playAudio( unsigned int audioId, bool forceRestart );
        bool stopAudio( unsigned int audioID );
        bool stopAllAudio( void );
 
        bool pauseAudio( unsigned int audioID );
        bool pauseAllAudio( void );
        bool resumeAudio( unsigned int audioID );
        bool resumeAllAudio( void );
       
        bool setSoundPosition( unsigned int audioID, Vector3 position );
       
        bool setSoundPosition( unsigned int audioID, Vector3 position,
            Vector3 velocity, Vector3 direction );
           
        bool setSound( unsigned int audioID, Vector3 position,
            Vector3 velocity, Vector3 direction, float maxDistance,
            bool playNow, bool forceRestart, float minGain );
       
        bool setListenerPosition( Vector3 position, Vector3 velocity,
            Quaternion orientation ); 
 };
 
 #endif /*__SOUNDMANAGER_H__*/

SoundManager.cpp

/**
 *  SoundManager.cpp
 *
 *  Original Code : Van Stokes, Jr. (http://www.EvilMasterMindsInc.com) - Aug 05
 *  Modified Code : Steven Gay - mec3@bluewin.ch - Septembre 2005
 *                  Deniz Sarikaya - daimler3@gmail.com - August 2010
 *
 */
 #include "SoundManager.h"
 
 SoundManager* SoundManager::mSoundManager = NULL;
 
 /****************************************************************************/
 SoundManager::SoundManager( void )
 {
    mSoundManager = this;
 
    isInitialised = false;
    isSoundOn = false;
    mSoundDevice = 0;
    mSoundContext = 0;
   
    mAudioPath = "";
   
    // EAX related
    isEAXPresent = false;
   
    // Initial position of the listener
    position[0] = 0.0;
    position[1] = 0.0;
    position[2] = 0.0;
   
    // Initial velocity of the listener
    velocity[0] = 0.0;
    velocity[1] = 0.0;
    velocity[2] = 0.0;
   
    // Initial orientation of the listener = direction + direction up
    orientation[0] = 0.0;
    orientation[1] = 0.0;
    orientation[2] = -1.0;
    orientation[3] = 0.0;
    orientation[4] = 1.0;
    orientation[5] = 0.0;
   
    // Needed because of hardware limitation
    mAudioBuffersInUseCount = 0;
    mAudioSourcesInUseCount = 0;
   
    for ( int i=0; i < MAX_AUDIO_SOURCES; i++ )
    {
       mAudioSources[i] = 0;
       mAudioSourceInUse[i] = false;
    }
   
    for ( int i=0; i < MAX_AUDIO_BUFFERS; i++ )
    {
       mAudioBuffers[i] = 0;
       strcpy( mAudioBufferFileName[i], "--" );
       mAudioBufferInUse[i] = false;
    }
   
   printf("SoudManager Created.\n");
 }
 
 /****************************************************************************/
 SoundManager::~SoundManager( void )
 {
   // Delete the sources and buffers
   alDeleteSources( MAX_AUDIO_SOURCES, mAudioSources );
   alDeleteBuffers( MAX_AUDIO_BUFFERS, mAudioBuffers );
   
    // Destroy the sound context and device
    mSoundContext = alcGetCurrentContext();
    mSoundDevice = alcGetContextsDevice( mSoundContext );
    alcMakeContextCurrent( NULL );
    alcDestroyContext( mSoundContext );
    if ( mSoundDevice)
        alcCloseDevice( mSoundDevice );
   
   printf("SoudManager Destroyed.\n");
 }
 
 /****************************************************************************/
 void SoundManager::selfDestruct( void )
 {
   if ( getSingletonPtr() ) delete getSingletonPtr();
 }
 
 /****************************************************************************/
 SoundManager* SoundManager::createManager( void )
 {
   if (mSoundManager == 0)
        mSoundManager = new SoundManager();
    return mSoundManager;
 }
 
 /****************************************************************************/
 bool SoundManager::init( void )
 {
   // It's an error to initialise twice OpenAl
   if ( isInitialised ) return true;
 
   // Open an audio device
   mSoundDevice = alcOpenDevice( NULL ); // TODO ((ALubyte*) "DirectSound3D");
   // mSoundDevice = alcOpenDevice( "DirectSound3D" );
 
   // Check for errors
   if ( !mSoundDevice )
   {
      printf( "SoundManager::init error : No sound device.\n");
      return false;
   }
    
   mSoundContext = alcCreateContext( mSoundDevice, NULL );
  //   if ( checkAlError() || !mSoundContext ) // TODO seems not to work! why ?
   if ( !mSoundContext )
   {
      printf( "SoundManager::init error : No sound context.\n");
      return false;
   }
   
   // Make the context current and active
   alcMakeContextCurrent( mSoundContext );
   if ( checkALError( "Init()" ) )
   {
      printf( "SoundManager::init error : could not make sound context current and active.\n");
      return false;
   }
   
   // Check for EAX 2.0 support and
   // Retrieves function entry addresses to API ARB extensions, in this case,
   // for the EAX extension. See Appendix 1 (Extensions) of
   // http://www.openal.org/openal_webstf/specs/OpenAL1-1Spec_html/al11spec7.html
   //
   // TODO EAX fct not used anywhere in the code ... !!!
   isEAXPresent = alIsExtensionPresent( "EAX2.0" );
   if ( isEAXPresent )
   {
      printf( "EAX 2.0 Extension available\n" );
 
 #ifdef _USEEAX
        eaxSet = (EAXSet) alGetProcAddress( "EAXSet" );
        if ( eaxSet == NULL )
            isEAXPresent = false;
 
        eaxGet = (EAXGet) alGetProcAddress( "EAXGet" );
        if ( eaxGet == NULL )
            isEAXPresent = false;
   
        if ( !isEAXPresent )
            checkALError( "Failed to get the EAX extension functions adresses.\n" );
 #else
        isEAXPresent = false;
        printf( "... but not used.\n" );
 #endif // _USEEAX
 
   }
   
   // Create the Audio Buffers
   alGenBuffers( MAX_AUDIO_BUFFERS, mAudioBuffers );
   if (checkALError("init::alGenBuffers:") )
        return false;
   
   // Generate Sources
   alGenSources( MAX_AUDIO_SOURCES, mAudioSources );
   if (checkALError( "init::alGenSources :") )
        return false;
 
   
   // Setup the initial listener parameters
   // -> location
   alListenerfv( AL_POSITION, position );
    
   // -> velocity
   alListenerfv( AL_VELOCITY, velocity );
   
   // -> orientation
   alListenerfv( AL_ORIENTATION, orientation );
   
   // Gain
   alListenerf( AL_GAIN, 1.0 );
   
   // Initialise Doppler
   alDopplerFactor( 1.0 ); // 1.2 = exaggerate the pitch shift by 20%
   alDopplerVelocity( 343.0f ); // m/s this may need to be scaled at some point
   
   // Ok
   isInitialised = true;
   isSoundOn = true;
 
   printf( "SoundManager initialised.\n\n");
   
   return true;
 }
 
 /****************************************************************************/
 bool SoundManager::checkALError( void )
 {
   ALenum errCode;
   if ( ( errCode = alGetError() ) != AL_NO_ERROR )
   {
      std::string err = "ERROR SoundManager:: ";
      err += (char*) alGetString( errCode );
      
      printf( "%s\n", err.c_str());
      return true;
   }
   return false;
 }
 
 /****************************************************************************/
 std::string SoundManager::listAvailableDevices( void )
 {
   std::string str = "Sound Devices available : ";
   
   if ( alcIsExtensionPresent( NULL, "ALC_ENUMERATION_EXT" ) == AL_TRUE )
   {
        str = "List of Devices : ";
        str += (char*) alcGetString( NULL, ALC_DEVICE_SPECIFIER );
        str += "\n";
   }
   else
        str += " ... eunmeration error.\n";
   
    return str;
 }
 
 /****************************************************************************/
 bool SoundManager::checkALError( std::string pMsg )
 {
   ALenum error = 0;
   
    if ( (error = alGetError()) == AL_NO_ERROR )
    return false;
 
   char mStr[256];
   switch ( error )
   {
        case AL_INVALID_NAME:
            sprintf(mStr,"ERROR SoundManager::%s Invalid Name", pMsg.c_str());
            break;
        case AL_INVALID_ENUM:
            sprintf(mStr,"ERROR SoundManager::%s Invalid Enum", pMsg.c_str());
            break;
        case AL_INVALID_VALUE:
            sprintf(mStr,"ERROR SoundManager::%s Invalid Value", pMsg.c_str());
            break;
        case AL_INVALID_OPERATION:
            sprintf(mStr,"ERROR SoundManager::%s Invalid Operation", pMsg.c_str());
            break;
        case AL_OUT_OF_MEMORY:
            sprintf(mStr,"ERROR SoundManager::%s Out Of Memory", pMsg.c_str());
            break;
        default:
            sprintf(mStr,"ERROR SoundManager::%s Unknown error (%i) case in testALError()", pMsg.c_str(), error);
            break;
   };
   
   printf( "%s\n", mStr );
   
   return true;
 }
 
 // Attempts to aquire an empty audio source and assign it back to the caller
 // via AudioSourceID. This will lock the source
 /*****************************************************************************/
 bool SoundManager::loadAudio( std::string filename, unsigned int *audioId,
    bool loop )
 {
   if ( filename.empty() || filename.length() > MAX_FILENAME_LENGTH )
        return false;
   
   if ( mAudioSourcesInUseCount == MAX_AUDIO_SOURCES )
        return false;   // out of Audio Source slots!
 
   int bufferID = -1;   // Identity of the Sound Buffer to use
   int sourceID = -1;   // Identity of the Source Buffer to use
 
   alGetError();    // Clear Error Code
 
   // Check and see if the pSoundFile is already loaded into a buffer
   bufferID = locateAudioBuffer( filename );
   if ( bufferID < 0 )
   {
      // The sound file isn't loaded in a buffer, lets attempt to load it on the fly
      bufferID = loadAudioInToSystem( filename );
      if ( bufferID < 0 ) return false;   // failed!
   }
 
   // If you are here, the sound the requester wants to reference is in a buffer.
   // Now, we need to find a free Audio Source slot in the sound system
   sourceID = 0;
   
   while ( mAudioSourceInUse[ sourceID ] == true ) sourceID++;
   
   // When you are here, 'mSourceID' now represents a free Audio Source slot
   // The free slot may not be at the end of the array but in the middle of it.
   *audioId = sourceID;  // return the Audio Source ID to the caller
   mAudioSourceInUse[ sourceID ] = true; // mark this Source slot as in use
   mAudioSourcesInUseCount++;    // bump the 'in use' counter
   
   // Now inform OpenAL of the sound assignment and attach the audio buffer
   // to the audio source
   alSourcei( mAudioSources[sourceID], AL_BUFFER, mAudioBuffers[bufferID] );
   
   // Steven : Not in the original code !!!!!
   alSourcei( mAudioSources[sourceID], AL_LOOPING, loop );
   
   if ( checkALError( "loadSource()::alSourcei" ) )
        return false;
   
   return true;
 }
 
 // Function to check and see if the pSoundFile is already loaded into a buffer
 /*****************************************************************************/
 int SoundManager::locateAudioBuffer( std::string filename )
 {
   for ( unsigned int b = 0; b < MAX_AUDIO_BUFFERS; b++ )
   {
      if ( filename == mAudioBufferFileName[b] ) return (int) b; // TODO Careful : converts unsigned to int!
   }
   return -1;      // not found
 }
 
 // Function to load a sound file into an AudioBuffer
 /*****************************************************************************/
 int SoundManager::loadAudioInToSystem( std::string filename )
 {
   if ( filename.empty() )
        return -1;
   
   // Make sure we have audio buffers available
   if ( mAudioBuffersInUseCount == MAX_AUDIO_BUFFERS ) return -1;
   
   // Find a free Audio Buffer slot
   int bufferID = 0;      // Identity of the Sound Buffer to use
   
   while ( mAudioBufferInUse[ bufferID ] == true ) bufferID++;
   
   // load .wav, .ogg or .au
/*  if ( filename.find( ".wav", 0 ) != std::string::npos )
    {
       printf(" ---> found Wav\n");
      // When you are here, bufferID now represents a free Audio Buffer slot
        // Attempt to load the SoundFile into the buffer
       if ( !loadWAV( filename, mAudioBuffers[ bufferID ] ) ) return -1;
   }
*/
   if ( filename.find( ".ogg", 0 ) != std::string::npos )
   {
       printf(" ---> found ogg\n");
       if ( !loadOGG( filename, mAudioBuffers[bufferID]) ) return -1;
   }
/* else if ( filename.find( ".au", 0 ) != std::string::npos )
   {
       printf(" ---> found au\n");
      // TODO if ( !loadAU( filename, mAudioBuffers[mBufferID]) ) return -1;
   }
*/
   
   // Successful load of the file into the Audio Buffer.
   mAudioBufferInUse[ bufferID ] = true;      // Buffer now in use
 
   strcpy( mAudioBufferFileName[ bufferID ], filename.c_str() ); // save the file descriptor
   
   mAudioBuffersInUseCount++;               // bump the 'in use' counter
   
   return bufferID;
 }
  
 /****************************************************************************/
 bool SoundManager::playAudio( unsigned int audioID, bool forceRestart )
 {
   // Make sure the audio source ident is valid and usable
   if ( audioID >= MAX_AUDIO_SOURCES || !mAudioSourceInUse[audioID])
        return false;
   
   int sourceAudioState = 0;
   
   alGetError();
   
   // Are we currently playing the audio source?
   alGetSourcei( mAudioSources[audioID], AL_SOURCE_STATE, &sourceAudioState );
   
   if ( sourceAudioState == AL_PLAYING )
   {
      if ( forceRestart )
           stopAudio( audioID );
        else
            return false; // Not forced, so we don't do anything
   }
   
   alSourcePlay( mAudioSources[ audioID ] );
   if ( checkALError( "playAudio::alSourcePlay: ") )
        return false;
   
    return true;
 }
  
 /****************************************************************************/
 bool SoundManager::pauseAudio( unsigned int audioID )
 {
   // Make sure the audio source ident is valid and usable
   if ( audioID >= MAX_AUDIO_SOURCES || !mAudioSourceInUse[audioID] )
        return false;
 
   alGetError();
 
   alSourcePause( mAudioSources[audioID] );
 
   if ( checkALError( "pauseAudio::alSourceStop ") )
        return false;
 
    return true;
 }
 
 /****************************************************************************/
 bool SoundManager::pauseAllAudio( void )
 {
   if ( mAudioSourcesInUseCount >= MAX_AUDIO_SOURCES )
        return false;
 
   alGetError();
 
   alSourcePausev( mAudioSourcesInUseCount, mAudioSources );
 
   if ( checkALError( "pauseAllAudio::alSourceStop ") )
        return false;
 
    return true;
 }
 
 // We could use playAudio instead !
 /****************************************************************************/
 bool SoundManager::resumeAudio( unsigned int audioID )
 {
   // Make sure the audio source ident is valid and usable
   if ( audioID >= MAX_AUDIO_SOURCES || !mAudioSourceInUse[audioID] )
        return false;
 
   alGetError();
 
   // If the sound was paused the sound will resume, else it will play from
   // the beginning !
   // TODO No check for forced restart. Verify if it is what you want ?
   alSourcePlay( mAudioSources[ audioID ] );
 
   if ( checkALError( "resumeAudio::alSourceStop ") )
        return false;
 
    return true;
 }
 
 /****************************************************************************/
 bool SoundManager::resumeAllAudio( void )
 {
   if ( mAudioSourcesInUseCount >= MAX_AUDIO_SOURCES )
        return false;
 
   alGetError();
 
   int sourceAudioState = 0;
 
   for ( int i=0; i<mAudioSourcesInUseCount; i++ )
   {
       // Are we currently playing the audio source?
       alGetSourcei( mAudioSources[i], AL_SOURCE_STATE, &sourceAudioState );
 
       if ( sourceAudioState == AL_PAUSED )
       {
           resumeAudio( i );
       }
   }
 
   if ( checkALError( "resumeAllAudio::alSourceStop ") )
        return false;
 
    return true;
 }
 
 /****************************************************************************/
 bool SoundManager::stopAudio( unsigned int audioID )
 {
   // Make sure the audio source ident is valid and usable
   if ( audioID >= MAX_AUDIO_SOURCES || !mAudioSourceInUse[audioID] )
        return false;
   
   alGetError();
   
   alSourceStop( mAudioSources[audioID] );
   
   if ( checkALError( "stopAudio::alSourceStop ") )
        return false;
   
    return true;
 }
 
 /****************************************************************************/
 bool SoundManager::stopAllAudio( void )
 {
   if ( mAudioSourcesInUseCount >= MAX_AUDIO_SOURCES )
        return false;
 
   alGetError();
 
   for ( int i=0; i<mAudioSourcesInUseCount; i++ )
   {
       stopAudio( i );
   }
 
   if ( checkALError( "stopAllAudio::alSourceStop ") )
        return false;
 
    return true;
 }
  
 /****************************************************************************/
 bool SoundManager::releaseAudio( unsigned int audioID )
 {
   if ( audioID >= MAX_AUDIO_SOURCES )
        return false;
   alSourceStop( mAudioSources[audioID] );
   mAudioSourceInUse[ audioID ] = false;
   mAudioSourcesInUseCount--;
    return true;
 }
 
 /****************************************************************************/
 bool SoundManager::setSound( unsigned int audioID, Vector3 position,
    Vector3 velocity, Vector3 direction, float maxDistance,
    bool playNow, bool forceRestart, float minGain )
 {
   if ( audioID >= MAX_AUDIO_SOURCES || !mAudioSourceInUse[ audioID ] )
        return false;
   
   // Set the position
   ALfloat pos[] = { position.x, position.y, position.z };
   
   alSourcefv( mAudioSources[ audioID ], AL_POSITION, pos );
   
   if ( checkALError( "setSound::alSourcefv:AL_POSITION" ) )
       return false;
   
   // Set the veclocity
   ALfloat vel[] = { velocity.x, velocity.y, velocity.z };
   
   alSourcefv( mAudioSources[ audioID ], AL_VELOCITY, vel );
   
   if ( checkALError( "setSound::alSourcefv:AL_VELOCITY" ) )
       return false;
    
   // Set the direction
   ALfloat dir[] = { velocity.x, velocity.y, velocity.z };
   
   alSourcefv( mAudioSources[ audioID ], AL_DIRECTION, dir );
   
   if ( checkALError( "setSound::alSourcefv:AL_DIRECTION" ) )
       return false;
   
   // Set the max audible distance
   alSourcef( mAudioSources[ audioID ], AL_MAX_DISTANCE, maxDistance );
   
   // Set the MIN_GAIN ( IMPORTANT - if not set, nothing audible! )
   alSourcef( mAudioSources[ audioID ], AL_MIN_GAIN, minGain );
   
   // Set the max gain
   alSourcef( mAudioSources[ audioID ], AL_MAX_GAIN, 1.0f ); // TODO as parameter ? global ?
   
   // Set the rollof factor
   alSourcef( mAudioSources[ audioID ], AL_ROLLOFF_FACTOR, 1.0f ); // TODO as parameter ?
   
   // Do we play the sound now ?
   if ( playNow ) return playAudio( audioID, forceRestart ); // TODO bof... not in this fct
   
   return true;
 }
 
 /****************************************************************************/
 bool SoundManager::setSoundPosition( unsigned int audioID, Vector3 position )
 {
   if ( audioID >= MAX_AUDIO_SOURCES || !mAudioSourceInUse[ audioID ] )
        return false;
   
   // Set the position
   ALfloat pos[] = { position.x, position.y, position.z };
   
   alSourcefv( mAudioSources[ audioID ], AL_POSITION, pos );
   
   if ( checkALError( "setSound::alSourcefv:AL_POSITION" ) )
       return false;
 
   return true;
 }
 
 /****************************************************************************/
 bool SoundManager::setSoundPosition( unsigned int audioID, Vector3 position,
    Vector3 velocity, Vector3 direction )
 {
   if ( audioID >= MAX_AUDIO_SOURCES || !mAudioSourceInUse[ audioID ] )
        return false;
   
   // Set the position
   ALfloat pos[] = { position.x, position.y, position.z };
   
   alSourcefv( mAudioSources[ audioID ], AL_POSITION, pos );
   
   if ( checkALError( "setSound::alSourcefv:AL_POSITION" ) )
       return false;
   
   // Set the veclocity
   ALfloat vel[] = { velocity.x, velocity.y, velocity.z };
   
   alSourcefv( mAudioSources[ audioID ], AL_VELOCITY, vel );
   
   if ( checkALError( "setSound::alSourcefv:AL_VELOCITY" ) )
       return false;
   
   // Set the direction
   ALfloat dir[] = { velocity.x, velocity.y, velocity.z };
   
   alSourcefv( mAudioSources[ audioID ], AL_DIRECTION, dir );
    
   if ( checkALError( "setSound::alSourcefv:AL_DIRECTION" ) )
       return false;
   
   return true;
 }
  
 /****************************************************************************/
 bool SoundManager::setListenerPosition( Vector3 position, Vector3 velocity,
    Quaternion orientation )
 {
   Vector3 axis;
   
   // Set the position
   ALfloat pos[] = { position.x, position.y, position.z };
   
   alListenerfv( AL_POSITION, pos );
   
   if ( checkALError( "setListenerPosition::alListenerfv:AL_POSITION" ) )
       return false;
   
   // Set the veclocity
   ALfloat vel[] = { velocity.x, velocity.y, velocity.z };
   
   alListenerfv( AL_VELOCITY, vel );
   
   if ( checkALError( "setListenerPosition::alListenerfv:AL_VELOCITY" ) )
       return false;
   
   // Orientation of the listener : look at then look up
   axis = Vector3::ZERO;
   axis.x = orientation.getYaw().valueRadians();
   axis.y = orientation.getPitch().valueRadians();
   axis.z = orientation.getRoll().valueRadians();
   
   // Set the direction
   ALfloat dir[] = { axis.x, axis.y, axis.z };
   
   alListenerfv( AL_ORIENTATION, dir );
   
   if ( checkALError( "setListenerPosition::alListenerfv:AL_DIRECTION" ) )
       return false;
   
   // TODO as parameters ?
   alListenerf( AL_MAX_DISTANCE, 10000.0f );
   alListenerf( AL_MIN_GAIN, 0.0f );
   alListenerf( AL_MAX_GAIN, 1.0f );
   alListenerf( AL_GAIN, 1.0f );
   
   return true;
 }
 
 bool SoundManager::loadOGG( std::string filename, ALuint pDestAudioBuffer )
 {    
    OggVorbis_File oggfile;

    if(ov_fopen(const_cast<char*>(filename.c_str()), &oggfile))
    {
        printf("SoundManager::loadOGG() : ov_fopen failed.\n");
        return false;
    }

    vorbis_info* info = ov_info(&oggfile, -1);

    ALenum format;
    switch(info->channels)
    {
        case 1:
            format = AL_FORMAT_MONO16; break;
        case 2:
            format = AL_FORMAT_STEREO16; break;
        case 4:
            format = alGetEnumValue("AL_FORMAT_QUAD16"); break;
        case 6:
            format = alGetEnumValue("AL_FORMAT_51CHN16"); break;
        case 7:
            format = alGetEnumValue("AL_FORMAT_61CHN16"); break;
        case 8:
            format = alGetEnumValue("AL_FORMAT_71CHN16"); break;
        default:
            format = 0; break;
    }

    std::vector<int16> samples;
    char tmpbuf[4096];
    int section = 0;
    bool firstrun = true;
    while(1)
    {
        int result = ov_read(&oggfile, tmpbuf, 4096, 0, 2, 1, &section);
        if(result > 0)
        {
            firstrun = false;
            samples.insert(samples.end(), tmpbuf, tmpbuf + (result));
        }
        else
        {
            if(result < 0)
            {
                printf("SoundManager::loadOGG() : Loading ogg sound data failed!");
                ov_clear(&oggfile);
                return false;
            }
            else
            {
                if(firstrun)
                    return false;
                break;
            }
        }
    }

    alBufferData(pDestAudioBuffer, format, &samples[0], ov_pcm_total(&oggfile, -1), info->rate);

    return true;
 }



Alias: OpenAL