cAudioSource.cpp

// Copyright (c) 2008-2011 Raynaldo (Wildicv) Rivera, Joshua (Dark_Kilauea) Jones, Murat (wolfmanfx) Sari
// This file is part of the "cAudio Engine"
// For conditions of distribution and use, see copyright notice in cAudio.h
 
#include "cAudioSource.h"
#include "cAudio.h"
#include "cLogger.h"
#include "cFilter.h"
#include "cEffect.h"
#include "cAudioSleep.h"
#include <string.h>
#include <algorithm>
 
#if CAUDIO_EFX_ENABLED == 1
#include "cOpenALDeviceContext.h"
#endif
 
namespace
{
    // return buffer length in seconds
    ALfloat GetBufferLength(ALuint buffer)
    {
        ALint size, bits, channels, freq;
 
        alGetBufferi(buffer, AL_SIZE, &size);
        alGetBufferi(buffer, AL_BITS, &bits);
        alGetBufferi(buffer, AL_CHANNELS, &channels);
        alGetBufferi(buffer, AL_FREQUENCY, &freq);
        if(alGetError() != AL_NO_ERROR || !bits || !channels || !freq)
            return -1.0f;
 
        return (ALfloat)((ALuint)size/channels/(bits/8)) / (ALfloat)freq;
    }
 
    ALint GetBufferSize(ALuint buffer)
    {
        ALint size;
        alGetBufferi(buffer, AL_SIZE, &size);
        return size;
    }
}
 
namespace cAudio
{
 
#if CAUDIO_EFX_ENABLED == 1
    cAudioSource::cAudioSource(IAudioDecoder* decoder, IAudioDeviceContext* context, cEFXFunctions* oALFunctions)
                : cAudioSourceBase(context), Decoder(decoder), Loop(false), Valid(false),
                EFX(oALFunctions), Filter(NULL), EffectSlotsAvailable(0), LastFilterTimeStamp(0)
#else
        cAudioSource::cAudioSource(IAudioDecoder* decoder, IAudioDeviceContext* context)
        : cAudioSourceBase(context), Decoder(decoder), Loop(false), Valid(false)
#endif
    {
                cAudioMutexBasicLock lock(Mutex);
 
        BufferPosition = 0;
        BufferTime = 0;
                for(int i=0; i<CAUDIO_SOURCE_NUM_BUFFERS; ++i) {
                        Buffers[i] = 0;
        }
 
#if CAUDIO_EFX_ENABLED == 1
                for(int i=0; i<CAUDIO_SOURCE_MAX_EFFECT_SLOTS; ++i)
                        Effects[i] = NULL;
 
                for(int i=0; i<CAUDIO_SOURCE_MAX_EFFECT_SLOTS; ++i)
                        LastEffectTimeStamp[i] = 0;
#endif
 
                if(Decoder)
                        Decoder->grab();
 
        ALboolean state = alIsSource(Source);
 
        if (state)
        {
            //Generates 3 buffers for the ogg file
            alGenBuffers(CAUDIO_SOURCE_NUM_BUFFERS, Buffers);
            state = !checkALError();
        }
 
#if CAUDIO_EFX_ENABLED == 1
                Valid = state && (Decoder != NULL) && (Context != NULL) && (EFX != NULL);
 
                int numSlots = 0;
                ALCdevice* device = alcGetContextsDevice(((cOpenALDeviceContext*)Context)->getOpenALContext());
                alcGetIntegerv(device, ALC_MAX_AUXILIARY_SENDS, 1, &numSlots);
 
                EffectSlotsAvailable = (numSlots <= CAUDIO_SOURCE_MAX_EFFECT_SLOTS) ? numSlots : CAUDIO_SOURCE_MAX_EFFECT_SLOTS;
#else
                Valid = state && (Decoder != NULL) && (Context != NULL);
#endif
    }
 
    cAudioSource::~cAudioSource()
    {
                cAudioMutexBasicLock lock(Mutex);
 
#if CAUDIO_EFX_ENABLED == 1
                for(int i=0; i<CAUDIO_SOURCE_MAX_EFFECT_SLOTS; ++i)
                {
                        if(Effects[i])
                                Effects[i]->drop();
                        Effects[i] = NULL;
                }
 
                if(Filter)
                        Filter->drop();
                Filter = NULL;
#endif
                
                //Stops the audio Source
                alSourceStop(Source);
        checkALError();
                empty();
        alSourcei(Source, AL_BUFFER, 0);
                //deletes the last filled buffer
                alDeleteBuffers(CAUDIO_SOURCE_NUM_BUFFERS, Buffers);
                checkALError();
 
                if(Decoder) {
                        Decoder->drop();
            Decoder = NULL;
        }
    }
 
    cAudioSourceBase::cAudioSourceBase(IAudioDeviceContext* context) : 
        Context(context), Volume(1.f), Source(0) 
    {
        alGenSources(1, &Source);
        checkALError();
        setVolume(Volume);
    }
 
    cAudioSourceBase::~cAudioSourceBase()
    {
        alSourceStop(Source);
        checkALError();
                alDeleteSources(1, &Source);
        checkALError();
 
                getLogger()->logDebug("Audio Source", "Audio source released.");
                signalEvent(ON_RELEASE);
    }
 
 
        bool cAudioSource::drop()
        {
                --RefCount;
                if (RefCount == 0)
                {
                        Context->getAudioManager()->release(this);
                        return true;
                }
                return false;
        }
 
        bool cAudioSource::play()
        {
                cAudioMutexBasicLock lock(Mutex);
                if (!isPaused())
        {
            int queueSize = 0;
                        //Purges all buffers from the source
                        alSourcei(Source, AL_BUFFER, 0);
            BufferPosition = Decoder->getCurrentPosition();
            BufferTime = Decoder->getCurrentTime();
                        checkALError();
            for(int u = 0; u < CAUDIO_SOURCE_NUM_BUFFERS; u++)
            {
                int val = stream(Buffers[u]);
 
                if(val < 0)
                {
                    return false;
                }
                else if(val > 0)
                    ++queueSize;
            }
            //Stores the sources 3 buffers to be used in the queue
            alSourceQueueBuffers(Source, queueSize, Buffers);
                        checkALError();
        }
#if CAUDIO_EFX_ENABLED == 1
                updateFilter();
                for(unsigned int i=0; i<CAUDIO_SOURCE_MAX_EFFECT_SLOTS; ++i)
                        updateEffect(i);
#endif
        alSourcePlay(Source);
                checkALError();
                getLogger()->logDebug("Audio Source", "Source playing.");
                signalEvent(ON_PLAY);
                oldState = AL_PLAYING;
        return true;
    }
 
        bool cAudioSource::play2d(const bool& toLoop)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcei(Source, AL_SOURCE_RELATIVE, true);
        loop(toLoop);
        bool state = play();
                checkALError();
                return state;
    }
 
        bool cAudioSource::play3d(const cVector3& position, const float& soundstr, const bool& toLoop)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcei(Source, AL_SOURCE_RELATIVE, false);
        setPosition(position);
        setStrength(soundstr);
        loop(toLoop);
        bool state = play();
                checkALError();
                return state;
    }
 
        void cAudioSource::pause()
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcePause(Source);
                checkALError();
                getLogger()->logDebug("Audio Source", "Source paused.");
                signalEvent(ON_PAUSE);
                oldState = AL_PAUSED;
    }
 
        void cAudioSource::stop()
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourceStop(Source);
 
                //INFO:FIXED EXTREME SLOWDOWN ON IPHONE
                int queued = 0;
                alGetSourcei(Source, AL_BUFFERS_QUEUED, &queued);
                while ( queued-- )
                {
                        ALuint buffer;
                        alSourceUnqueueBuffers(Source, 1, &buffer);
                }
 
                //Resets the audio to the beginning
                Decoder->setPosition(0, false);
                checkALError();
                getLogger()->logDebug("Audio Source", "Source stopped.");
                signalEvent(ON_STOP);
                oldState = AL_STOPPED;
    }
 
        void cAudioSource::loop(const bool& loop)
        {
                cAudioMutexBasicLock lock(Mutex);
        Loop = loop;
    }
 
        bool cAudioSource::seek(const float& seconds, bool relative)
        {
                bool state = false;
                cAudioMutexBasicLock lock(Mutex);
        if(Decoder->isSeekingSupported())
        {
                        state = Decoder->seek(seconds, relative);
 
            BufferPosition = Decoder->getCurrentPosition();
            BufferTime = Decoder->getCurrentTime();
 
            int queued = 0;
            alGetSourcei(Source, AL_BUFFERS_QUEUED, &queued);
            if (queued) {
                BufferPosition -= queued * GetBufferSize(Buffers[0]);
                BufferTime -= queued * GetBufferLength(Buffers[0]);
            }
        }
                return state;
    }
 
        float cAudioSource::getTotalAudioTime()
        {
                return Decoder->getTotalTime();
        }
 
        int cAudioSource::getTotalAudioSize()
        {
                return Decoder->getTotalSize();
        }
 
        int cAudioSource::getCompressedAudioSize()
        {
                return Decoder->getCompressedSize();
        }
 
        float cAudioSource::getCurrentAudioTime()
        {
        float time = -1;
        alGetSourcef(Source, AL_SEC_OFFSET, &time);
        return BufferTime + time;
        }
 
        int cAudioSource::getCurrentAudioPosition()
        {
        int offset = -1;
        alGetSourcei(Source, AL_BYTE_OFFSET, &offset);
                return BufferPosition + offset;
        }
 
        int cAudioSource::getCurrentCompressedAudioPosition()
        {
                return Decoder->getCurrentCompressedPosition();
        }
 
        bool cAudioSource::update()
        {
                cAudioMutexBasicLock lock(Mutex);
 
                int processed = 0;
                bool active = true;
        if(isValid() || isPlaying())
                {
#if CAUDIO_EFX_ENABLED == 1
                        updateFilter();
                        for(unsigned int i=0; i<CAUDIO_SOURCE_MAX_EFFECT_SLOTS; ++i)
                                updateEffect(i);
#endif
 
                        //gets the sound source processed buffers
                        alGetSourcei(Source, AL_BUFFERS_PROCESSED, &processed);
            checkALError();
            
                        //while there is more data refill buffers with audio data.
                        while (processed--)
                        {
                                ALuint buffer;
                                alSourceUnqueueBuffers(Source, 1, &buffer);
                BufferPosition += GetBufferSize(buffer);
                BufferTime += GetBufferLength(buffer);
 
                                if (checkALError()) 
                                {
                                        processed++;
                                        cAudioSleep(1);
                                        continue;
                                }
 
                                active = stream(buffer);
 
                                //if more in stream continue playing.
                                if(active)
                                {
                                        alSourceQueueBuffers(Source, 1, &buffer);
                                }
 
                                if (checkALError()) 
                                {
                                        processed++;
                                        cAudioSleep(1);
                                        continue;
                                }
                        }
 
                        signalEvent(ON_UPDATE);
                }
 
                ALenum state;
                alGetSourcei(Source, AL_SOURCE_STATE, &state);
        checkALError();
                if(state == AL_STOPPED && oldState != state)
                {
                        //Resets the audio to the beginning
                        Decoder->setPosition(0, false);
                        getLogger()->logDebug("Audio Source", "Source stopped.");
                        signalEvent(ON_STOP);
                        oldState = state;
                }
 
                return active;
    }
 
        bool cAudioSource::isValid() const
        {
        return Valid;
        }
 
        bool cAudioSourceBase::isPlaying() const
        {
                ALenum state = 0;
        alGetSourcei(Source, AL_SOURCE_STATE, &state);
        checkALError();
        return (state == AL_PLAYING);
    }
 
        bool cAudioSourceBase::isPaused() const
        {
                ALenum state = 0;
        alGetSourcei(Source, AL_SOURCE_STATE, &state);
        checkALError();
        return (state == AL_PAUSED);
    }
 
        bool cAudioSourceBase::isStopped() const
        {
                ALenum state = 0;
        alGetSourcei(Source, AL_SOURCE_STATE, &state);
        checkALError();
                return (state == AL_STOPPED);
    }
 
        bool cAudioSource::isLooping() const
        {
                return Loop;
        }
 
        void cAudioSourceBase::setPosition(const cVector3& position)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSource3f(Source, AL_POSITION, position.x, position.y, position.z);
                checkALError();
    }
 
        void cAudioSourceBase::setVelocity(const cVector3& velocity)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSource3f(Source, AL_VELOCITY, velocity.x, velocity.y, velocity.z);
                checkALError();
    }
 
        void cAudioSourceBase::setDirection(const cVector3& direction)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSource3f(Source, AL_DIRECTION, direction.x, direction.y, direction.z);
                checkALError();
    }
 
        void cAudioSourceBase::setRolloffFactor(const float& rolloff)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_ROLLOFF_FACTOR, rolloff);
                checkALError();
    }
 
        void cAudioSourceBase::setStrength(const float& soundstrength)
        {
                float inverseStrength = 0.0f;
                if(soundstrength > 0.0f)
                        inverseStrength = 1.0f / soundstrength;
 
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_ROLLOFF_FACTOR, inverseStrength);
                checkALError();
    }
 
        void cAudioSourceBase::setMinDistance(const float& minDistance)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_REFERENCE_DISTANCE, minDistance);
                checkALError();
        }
 
        void cAudioSourceBase::setMaxAttenuationDistance(const float& maxDistance)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_MAX_DISTANCE, maxDistance);
                checkALError();
        }
 
        void cAudioSourceBase::setPitch(const float& pitch)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef (Source, AL_PITCH, pitch);
                checkALError();
    }
 
        void cAudioSourceBase::setVolume(const float& volume)
        {
                cAudioMutexBasicLock lock(Mutex);
                Volume = volume;
        alSourcef(Source, AL_GAIN, Volume * Context->getAudioManager()->getMasterVolume());
                checkALError();
    }
 
        void cAudioSourceBase::setMinVolume(const float& minVolume)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_MIN_GAIN, minVolume);
                checkALError();
        }
 
        void cAudioSourceBase::setMaxVolume(const float& maxVolume)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_MAX_GAIN, maxVolume);
                checkALError();
        }
 
        void cAudioSourceBase::setInnerConeAngle(const float& innerAngle)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_CONE_INNER_ANGLE, innerAngle);
                checkALError();
        }
 
        void cAudioSourceBase::setOuterConeAngle(const float& outerAngle)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_CONE_OUTER_ANGLE, outerAngle);
                checkALError();
        }
 
        void cAudioSourceBase::setOuterConeVolume(const float& outerVolume)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_CONE_OUTER_GAIN, outerVolume);
                checkALError();
        }
 
        void cAudioSourceBase::setDopplerStrength(const float& dstrength)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSourcef(Source, AL_DOPPLER_FACTOR, dstrength);
                checkALError();
    }
 
        void cAudioSourceBase::setDopplerVelocity(const cVector3& dvelocity)
        {
                cAudioMutexBasicLock lock(Mutex);
        alSource3f(Source, AL_DOPPLER_VELOCITY, dvelocity.x, dvelocity.y, dvelocity.z);
                checkALError();
    }
 
        void cAudioSourceBase::move(const cVector3& position)
        {
                cAudioMutexBasicLock lock(Mutex);
                cVector3 oldPos = getPosition();
                cVector3 velocity = position - oldPos;
 
        alSource3f(Source, AL_VELOCITY, velocity.x, velocity.y, velocity.z);
                alSource3f(Source, AL_POSITION, position.x, position.y, position.z);
                checkALError();
        }
 
        cVector3 cAudioSourceBase::getPosition() const
        {
                cVector3 position;
                alGetSourcefv(Source, AL_POSITION, &position.x);
        checkALError();
                return position;
        }
 
        cVector3 cAudioSourceBase::getVelocity() const
        {
                cVector3 velocity;
                alGetSourcefv(Source, AL_VELOCITY, &velocity.x);
                return velocity;
        }
 
        cVector3 cAudioSourceBase::getDirection() const
        {
                cVector3 direction;
                alGetSourcefv(Source, AL_DIRECTION, &direction.x);
        checkALError();
                return direction;
        }
 
        float cAudioSourceBase::getRolloffFactor() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_ROLLOFF_FACTOR, &value);
        checkALError();
                return value;
        }
 
        float cAudioSourceBase::getStrength() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_ROLLOFF_FACTOR, &value);
        checkALError();
        
                float inverseStrength = 0.0f;
                if(value > 0.0f)
                        inverseStrength = 1.0f / value;
 
                return inverseStrength;
        }
 
        float cAudioSourceBase::getMinDistance() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_REFERENCE_DISTANCE, &value);
        checkALError();
                return value;
        }
 
        float cAudioSourceBase::getMaxDistance() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_MAX_DISTANCE, &value);
        checkALError();
                return value;
        }
 
    bool cAudioSourceBase::isRelative() const
    {
        int relative = 0;
        alGetSourcei(Source, AL_SOURCE_RELATIVE, &relative);
        return relative;
    }
 
    float cAudioSourceBase::calculateGain() const
    {
        // OpenAL Inverse Distance Clamped Model
        // distance = max(distance,AL_REFERENCE_DISTANCE);
        // distance = min(distance,AL_MAX_DISTANCE);
        // gain = AL_REFERENCE_DISTANCE / (AL_REFERENCE_DISTANCE +
        //                                 AL_ROLLOFF_FACTOR *
        //                                 (distance – AL_REFERENCE_DISTANCE));
 
        cVector3 lpos = Context->getAudioManager()->getListener()->getPosition();
        cVector3 pos  = getPosition();
 
        float refDist =  getMinDistance();
        float dist = 0.f;
        dist = isRelative() ? pos.length() : (pos - lpos).length();
        dist = std::max(dist, refDist);
        dist = std::min(dist, getMaxDistance());
        float gain = refDist / (refDist + getRolloffFactor() * (dist - refDist));
        return gain * getVolume();
    }
 
        float cAudioSourceBase::getPitch() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_PITCH, &value);
        checkALError();
                return value;
        }
 
        float cAudioSourceBase::getVolume() const
        {
                return Volume;
        }
 
        float cAudioSourceBase::getMinVolume() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_MIN_GAIN, &value);
        checkALError();
                return value;
        }
 
        float cAudioSourceBase::getMaxVolume() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_MAX_GAIN, &value);
        checkALError();
                return value;
        }
 
        float cAudioSourceBase::getInnerConeAngle() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_CONE_INNER_ANGLE, &value);
        checkALError();
                return value;
        }
 
        float cAudioSourceBase::getOuterConeAngle() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_CONE_OUTER_ANGLE, &value);
        checkALError();
                return value;
        }
 
        float cAudioSourceBase::getOuterConeVolume() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_CONE_OUTER_GAIN, &value);
        checkALError();
                return value;
        }
 
        float cAudioSourceBase::getDopplerStrength() const
        {
                float value = 0.0f;
                alGetSourcef(Source, AL_DOPPLER_FACTOR, &value);
        checkALError();
                return value;
        }
 
        cVector3 cAudioSourceBase::getDopplerVelocity() const
        {
                cVector3 velocity;
                alGetSourcefv(Source, AL_DOPPLER_VELOCITY, &velocity.x);
        checkALError();
                return velocity;
        }
 
#if CAUDIO_EFX_ENABLED == 1
        unsigned int cAudioSource::getNumEffectSlotsAvailable() const
        {
                return EffectSlotsAvailable;
        }
 
        bool cAudioSource::attachEffect(unsigned int slot, IEffect* effect)
        {
                cAudioMutexBasicLock lock(Mutex);
                if(slot < EffectSlotsAvailable)
                {
                        Effects[slot] = effect;
 
                        if(Effects[slot])
                                Effects[slot]->grab();
 
                        updateEffect(slot);
                        return true;
                }
                return false;
        }
 
        void cAudioSource::removeEffect(unsigned int slot)
        {
                cAudioMutexBasicLock lock(Mutex);
                if(slot < EffectSlotsAvailable)
                {
                        if(Effects[slot])
                                Effects[slot]->drop();
 
                        Effects[slot] = NULL;
                        LastEffectTimeStamp[slot] = 0;
                        updateEffect(slot, true);
                }
        }
 
        bool cAudioSource::attachFilter(IFilter* filter)
        {
                cAudioMutexBasicLock lock(Mutex);
                Filter = filter;
 
                if(Filter)
                        Filter->grab();
 
                updateFilter();
                return true;
        }
 
        void cAudioSource::removeFilter()
        {
                cAudioMutexBasicLock lock(Mutex);
                if(Filter)
                        Filter->drop();
                Filter = NULL;
                LastFilterTimeStamp = 0;
                updateFilter(true);
        }
#endif
 
    void cAudioSource::empty()
    {
        int queued = 0;
        alGetSourcei(Source, AL_BUFFERS_QUEUED, &queued);
        checkALError();
        
        while (queued--)
        {
            ALuint buffer;
            alSourceUnqueueBuffers(Source, 1, &buffer);
                        checkALError();
        }
    }
 
    bool cAudioSource::stream(ALuint buffer)
    {
        if(!Decoder)
            return false;
        
        //stores the calculated data into buffer that is passed to output.
        size_t totalread = 0;
        unsigned int errorcount = 0;
        char tempbuffer[CAUDIO_SOURCE_BUFFER_SIZE];
        while( totalread < CAUDIO_SOURCE_BUFFER_SIZE )
        {
            char tempbuffer2[CAUDIO_SOURCE_BUFFER_SIZE];
            Mutex.unlock();    // this can take a long time
            int actualread = Decoder->readAudioData(tempbuffer2, CAUDIO_SOURCE_BUFFER_SIZE-totalread);
            Mutex.lock();
            
            if(actualread > 0)
            {
                memcpy(tempbuffer+totalread,tempbuffer2,actualread);
                totalread += actualread;
            }
            if(actualread < 0)
            {
                ++errorcount;
                getLogger()->logDebug("Audio Source", "Decoder returned an error: %i (%i of 3)", actualread, errorcount);
                if(errorcount >= 3)
                {
                    stop();
                    break;
                }
            }
            if(actualread == 0)
            {
                if(isLooping())
                {
                    //If we are to loop, set to the beginning and reload from the start
                    Decoder->setPosition(0, false);
                    getLogger()->logDebug("Audio Source", "Buffer looping.");
                }
                else
                    break;
            }
        }
 
        //Second check, in case looping is not enabled, we will return false for end of stream
        if(totalread == 0)
        {
            return false;
        }
        getLogger()->logDebug("Audio Source", "Buffered %i bytes of data into buffer %i at %i hz.", totalread, buffer, Decoder->getFrequency());
        alBufferData(buffer, convertAudioFormatEnum(Decoder->getFormat()), tempbuffer, totalread, Decoder->getFrequency());
        checkALError();
        return true;
    }
 
#if CAUDIO_EFX_ENABLED == 1
        void cAudioSource::updateFilter(bool remove)
        {
                if(!remove)
                {
                        if(Filter && Filter->isValid())
                        {
                                if(LastFilterTimeStamp != Filter->getLastUpdated())
                                {
                                        LastFilterTimeStamp = Filter->getLastUpdated();
                                        cFilter* theFilter = static_cast<cFilter*>(Filter);
                                        if(theFilter)
                                        {
                                                alSourcei(Source, AL_DIRECT_FILTER, theFilter->getOpenALFilter());
                                                checkALError();
                                                return;
                                        }
                                }
                                return;
                        }
                }
                alSourcei(Source, AL_DIRECT_FILTER, AL_FILTER_NULL);
                checkALError();
        }
 
        void cAudioSource::updateEffect(unsigned int slot, bool remove)
        {
                if(slot < EffectSlotsAvailable)
                {
                        if(!remove)
                        {
                                if(Effects[slot] && Effects[slot]->isValid())
                                {
                                        if(LastEffectTimeStamp[slot] != Effects[slot]->getLastUpdated())
                                        {
                                                LastEffectTimeStamp[slot] = Effects[slot]->getLastUpdated();
                                                cEffect* theEffect = static_cast<cEffect*>(Effects[slot]);
                                                if(theEffect)
                                                {
                                                        ALuint filterID = AL_FILTER_NULL;
                                                        cFilter* theFilter = static_cast<cFilter*>(theEffect->getFilter());
                                                        if(theFilter)
                                                        {
                                                                filterID = theFilter->getOpenALFilter();
                                                        }
                                                        alSource3i(Source, AL_AUXILIARY_SEND_FILTER, theEffect->getOpenALEffectSlot(), slot, filterID);
                                                        checkALError();
                                                        return;
                                                }
                                        }
                                        return;
                                }
                        }
                        alSource3i(Source, AL_AUXILIARY_SEND_FILTER, AL_EFFECTSLOT_NULL, slot, AL_FILTER_NULL);
                        checkALError();
                }
        }
#endif
 
        void cAudioSourceBase::registerEventHandler(ISourceEventHandler* handler)
        {
                if(handler)
                {
                    cAudioMutexBasicLock lock(Mutex);
                        eventHandlerList.push_back(handler);
                }
        }
 
        void cAudioSourceBase::unRegisterEventHandler(ISourceEventHandler* handler)
        {
                if(handler)
                {
                    cAudioMutexBasicLock lock(Mutex);
            for(int i=0; i<eventHandlerList.size(); i++) {
                if(eventHandlerList[i] == handler)
                    eventHandlerList.erase(eventHandlerList.begin() + i);
            }
                }
        }
 
        void cAudioSourceBase::unRegisterAllEventHandlers()
        {
            cAudioMutexBasicLock lock(Mutex);
                eventHandlerList.clear();
        }
 
        void cAudioSourceBase::signalEvent(Events sevent)
        {
                cAudioMutexBasicLock lock(Mutex);
                if(eventHandlerList.empty())
            return;
 
        size_t size = eventHandlerList.size();
 
        for(int i=0; i<size; )
        {
            ISourceEventHandler *handler = eventHandlerList[i];
 
            switch(sevent)
            {
            case ON_UPDATE:  handler->onUpdate(); break;
            case ON_RELEASE: handler->onRelease(); break;
            case ON_PLAY:    handler->onPlay(); break;
            case ON_PAUSE:   handler->onPause(); break;
            case ON_STOP:    handler->onStop(); break;
            }
     
            // handler may have unregistered itself
            if(size == eventHandlerList.size()) {
                i++;
            } else {
                size = eventHandlerList.size();
            }
        }
    }
}