C++ IXAudio2SourceVoice::SetVolume方法代码示例

	bool Audio::AddAudioFile(const char* i_AudioPath, bool bLoop, float i_InitialVolume)
	{
		WAVEFORMATEXTENSIBLE wfx = { 0 };
		XAUDIO2_BUFFER buffer = { 0 };

		// Open the file
		HANDLE hFile = CreateFile(
			i_AudioPath,
			GENERIC_READ,
			FILE_SHARE_READ,
			NULL,
			OPEN_EXISTING,
			0,
			NULL);


		SetFilePointer(hFile, 0, NULL, FILE_BEGIN);

		DWORD dwChunkSize;
		DWORD dwChunkPosition;
		//check the file type, should be fourccWAVE or 'XWMA'
		FindChunk(hFile, fourccRIFF, dwChunkSize, dwChunkPosition);
		DWORD filetype;
		ReadChunkData(hFile, &filetype, sizeof(DWORD), dwChunkPosition);
		if (filetype != fourccWAVE)
			return false;

		FindChunk(hFile, fourccFMT, dwChunkSize, dwChunkPosition);
		ReadChunkData(hFile, &wfx, dwChunkSize, dwChunkPosition);

		//fill out the audio data buffer with the contents of the fourccDATA chunk
		FindChunk(hFile, fourccDATA, dwChunkSize, dwChunkPosition);
		BYTE * pDataBuffer = new BYTE[dwChunkSize];
		ReadChunkData(hFile, pDataBuffer, dwChunkSize, dwChunkPosition);

		buffer.AudioBytes = dwChunkSize;  //buffer containing audio data
		buffer.pAudioData = pDataBuffer;  //size of the audio buffer in bytes
		buffer.Flags = XAUDIO2_END_OF_STREAM; // tell the source voice not to expect any data after this buffer
		if (bLoop)
		{
			buffer.LoopLength = 0;
			buffer.LoopCount = XAUDIO2_LOOP_INFINITE;
		}

		HRESULT hr;
		IXAudio2SourceVoice* pSourceVoice;
		if (FAILED(hr = s_pXAudio2->CreateSourceVoice(&pSourceVoice, (WAVEFORMATEX*)&wfx)))
			return false;

		if (FAILED(hr = pSourceVoice->SubmitSourceBuffer(&buffer)))
			return false;

		pSourceVoice->SetVolume(i_InitialVolume);

		s_SourceVoices.push_back(pSourceVoice);
		s_AudioBuffers.push_back(buffer);
	}

void Sound::playSoundEffect(SoundEffect effect, X3DAUDIO_EMITTER* emit)
{
	IXAudio2SourceVoice* voice = getSFXVoice();

	voice->FlushSourceBuffers();
	
	switch (effect) {
	case SFX_LASER:
		{
			voice->SubmitSourceBuffer(laserBufferDetails, laserWMABuffer);
			break;
		}
	case SFX_CRASH:
		{
			voice->SubmitSourceBuffer(crashBufferDetails, crashWMABuffer);
			break;
		}
	case SFX_BOOST:
		{
			voice->SubmitSourceBuffer(boostBufferDetails, boostWMABuffer);
			break;
		}
	case SFX_DROPMINE:
		{
			voice->SubmitSourceBuffer(dropmineBufferDetails, dropmineWMABuffer);
			break;
		}
	case SFX_SCREAM:
		{
			// Now pick one of the three screams randomly
			int choice = std::rand() % 3;


			voice->SetVolume(2.0f);
			switch (choice) {
				case 0:	voice->SubmitSourceBuffer(scream1BufferDetails, scream1WMABuffer);
					break;
				case 1:	voice->SubmitSourceBuffer(scream2BufferDetails, scream2WMABuffer);
					break;
				case 2:	voice->SubmitSourceBuffer(scream3BufferDetails, scream3WMABuffer);
					break;
				default:
					voice->SubmitSourceBuffer(scream1BufferDetails, scream1WMABuffer);
			}

			break;
		}
	case SFX_CAREXPLODE:
		{
			voice->SetVolume(2.0f);
			voice->SubmitSourceBuffer(carexplodeBufferDetails, carexplodeWMABuffer);
			break;
		}
	case SFX_EXPLOSION:
		{
			voice->SubmitSourceBuffer(explosionBufferDetails, explosionWMABuffer);
			break;
		}
	case SFX_BEEP:
		{
			voice->SubmitSourceBuffer(beepBufferDetails, beepWMABuffer);
			break;
		}
	case SFX_ROCKETLAUNCH:
		{
			voice->SubmitSourceBuffer(rocketlaunchBufferDetails, rocketlaunchWMABuffer);
			break;
		}
	case SFX_PICKUP:
		{
			voice->SetVolume(2.0f);
			voice->SubmitSourceBuffer(pickupBufferDetails, pickupWMABuffer);
			break;
		}
	case SFX_SELECT:
		{
			voice->SubmitSourceBuffer(selectBufferDetails, selectWMABuffer);
			break;
		}
	case SFX_SHOTGUN:
		{
			voice->SetVolume(2.5f);
			voice->SubmitSourceBuffer(shotgunBufferDetails, shotgunWMABuffer);
			break;
		}
	case SFX_TAKENLEAD:
		{
			voice->SubmitSourceBuffer(takenleadBufferDetails, takenleadWMABuffer);
			break;
		}
	case SFX_LOSTLEAD:
		{
			voice->SubmitSourceBuffer(lostleadBufferDetails, lostleadWMABuffer);
			break;
		}
	case SFX_NOAMMO:
		{
			voice->SubmitSourceBuffer(noammoBufferDetails, noammoWMABuffer);
			break;
		}
//.........这里部分代码省略.........

void WaveBank::Impl::Play( int index, float volume, float pitch, float pan )
{
    assert( volume >= -XAUDIO2_MAX_VOLUME_LEVEL && volume <= XAUDIO2_MAX_VOLUME_LEVEL );
    assert( pitch >= -1.f && pitch <= 1.f );
    assert( pan >= -1.f && pan <= 1.f );

    if ( mStreaming )
    {
        DebugTrace( "ERROR: One-shots can only be created from an in-memory wave bank\n");
        throw std::exception( "WaveBank::Play" );
    }

    if ( index < 0 || uint32_t(index) >= mReader.Count() )
    {
        DebugTrace( "WARNING: Index %d not found in wave bank with only %u entries, one-shot not triggered\n", index, mReader.Count() );
        return;
    }

    if ( !mPrepared )
    {
        mReader.WaitOnPrepare();
        mPrepared = true;
    }

    char wfxbuff[64];
    auto wfx = reinterpret_cast<WAVEFORMATEX*>( wfxbuff );
    HRESULT hr = mReader.GetFormat( index, wfx, 64 );
    ThrowIfFailed( hr );

    IXAudio2SourceVoice* voice = nullptr;
    mEngine->AllocateVoice( wfx, SoundEffectInstance_Default, true, &voice );

    if ( !voice )
        return;

    if ( volume != 1.f )
    {
        hr = voice->SetVolume( volume );
        ThrowIfFailed( hr );
    }

    if ( pitch != 0.f )
    {
        float fr = XAudio2SemitonesToFrequencyRatio( pitch * 12.f );

        hr = voice->SetFrequencyRatio( fr );
        ThrowIfFailed( hr );
    }

    if ( pan != 0.f )
    {
        float matrix[16];
        if ( ComputePan( pan, wfx->nChannels, matrix ) )
        {
            hr = voice->SetOutputMatrix( nullptr, wfx->nChannels, mEngine->GetOutputChannels(), matrix );
            ThrowIfFailed( hr );
        }
    }

    hr = voice->Start( 0 );
    ThrowIfFailed( hr );

    XAUDIO2_BUFFER buffer;
    memset( &buffer, 0, sizeof(buffer) );

    hr = mReader.GetWaveData( index, &buffer.pAudioData, buffer.AudioBytes );
    ThrowIfFailed( hr );

    WaveBankReader::Metadata metadata;
    hr = mReader.GetMetadata( index, metadata );
    ThrowIfFailed( hr );

    buffer.Flags = XAUDIO2_END_OF_STREAM;
    buffer.pContext = this;

#if defined(_XBOX_ONE) || (_WIN32_WINNT < _WIN32_WINNT_WIN8) || (_WIN32_WINNT >= _WIN32_WINNT_WIN10)

    XAUDIO2_BUFFER_WMA wmaBuffer;
    memset( &wmaBuffer, 0, sizeof(wmaBuffer) );

    uint32_t tag;
    hr = mReader.GetSeekTable( index, &wmaBuffer.pDecodedPacketCumulativeBytes, wmaBuffer.PacketCount, tag );
    ThrowIfFailed( hr );

    if ( tag == WAVE_FORMAT_WMAUDIO2 || tag == WAVE_FORMAT_WMAUDIO3 )
    {
        hr = voice->SubmitSourceBuffer( &buffer, &wmaBuffer );
    }
    else
#endif
    {
        hr = voice->SubmitSourceBuffer( &buffer, nullptr );
    }
    if ( FAILED(hr) )
    {
        DebugTrace( "ERROR: WaveBank failed (%08X) when submitting buffer:\n", hr );
        DebugTrace( "\tFormat Tag %u, %u channels, %u-bit, %u Hz, %u bytes\n", wfx->wFormatTag, 
                    wfx->nChannels, wfx->wBitsPerSample, wfx->nSamplesPerSec, metadata.lengthBytes );
        throw std::exception( "SubmitSourceBuffer" );
    }
//.........这里部分代码省略.........