2 files changed, 740 insertions, 54 deletions

diff --git a/src/audio/oal/stream.cpp b/src/audio/oal/stream.cpp
index 3a1f748f..cdf063fa 100644
--- a/src/audio/oal/stream.cpp
+++ b/src/audio/oal/stream.cpp
@@ -8,10 +8,14 @@
 #include <opusfile.h>
 #else
 #ifdef _WIN32
+#ifdef AUDIO_OAL_USE_SNDFILE
 #pragma comment( lib, "libsndfile-1.lib" )
+#endif
 #pragma comment( lib, "libmpg123-0.lib" )
 #endif
+#ifdef AUDIO_OAL_USE_SNDFILE
 #include <sndfile.h>
+#endif
 #include <mpg123.h>
 #endif
 
@@ -19,7 +23,374 @@
 #include "crossplatform.h"
 #endif
 
+/*
+As we ran onto an issue of having different volume levels for mono streams
+and stereo streams we are now handling all the stereo panning ourselves.
+Each stream now has two sources - one panned to the left and one to the right,
+and uses two separate buffers to store data for each individual channel.
+For that we also have to reshuffle all decoded PCM stereo data from LRLRLRLR to
+LLLLRRRR (handled by CSortStereoBuffer).
+*/
+
+class CSortStereoBuffer
+{
+	uint16* PcmBuf;
+	size_t BufSize;
+public:
+	CSortStereoBuffer() : PcmBuf(nil), BufSize(0) {}
+	~CSortStereoBuffer()
+	{
+		if (PcmBuf)
+			free(PcmBuf);
+	}
+
+	uint16* GetBuffer(size_t size)
+	{
+		if (size == 0) return nil;
+		if (!PcmBuf)
+		{
+			BufSize = size;
+			PcmBuf = (uint16*)malloc(BufSize);
+		}
+		else if (BufSize < size)
+		{
+			BufSize = size;
+			PcmBuf = (uint16*)realloc(PcmBuf, size);
+		}
+		return PcmBuf;
+	}
+
+	void SortStereo(void* buf, size_t size)
+	{
+		uint16* InBuf = (uint16*)buf;
+		uint16* OutBuf = GetBuffer(size);
+
+		if (!OutBuf) return;
+
+		size_t rightStart = size / 4;
+		for (size_t i = 0; i < size / 4; i++)
+		{
+			OutBuf[i] = InBuf[i*2];
+			OutBuf[i+rightStart] = InBuf[i*2+1];
+		}
+
+		memcpy(InBuf, OutBuf, size);
+	}
+
+};
+
+CSortStereoBuffer SortStereoBuffer;
+
 #ifndef AUDIO_OPUS
+class CImaADPCMDecoder
+{
+	const uint16 StepTable[89] = {
+		7, 8, 9, 10, 11, 12, 13, 14,
+		16, 17, 19, 21, 23, 25, 28, 31,
+		34, 37, 41, 45, 50, 55, 60, 66,
+		73, 80, 88, 97, 107, 118, 130, 143,
+		157, 173, 190, 209, 230, 253, 279, 307,
+		337, 371, 408, 449, 494, 544, 598, 658,
+		724, 796, 876, 963, 1060, 1166, 1282, 1411,
+		1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024,
+		3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484,
+		7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
+		15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794,
+		32767
+	};
+
+	int16 Sample, StepIndex;
+
+public:
+	CImaADPCMDecoder()
+	{
+		Init(0, 0);
+	}
+
+	void Init(int16 _Sample, int16 _StepIndex)
+	{
+		Sample = _Sample;
+		StepIndex = _StepIndex;
+	}
+
+	void Decode(uint8 *inbuf, int16 *_outbuf, size_t size)
+	{
+		int16* outbuf = _outbuf;
+		for (size_t i = 0; i < size; i++)
+		{
+			*(outbuf++) = DecodeSample(inbuf[i] & 0xF);
+			*(outbuf++) = DecodeSample(inbuf[i] >> 4);
+		}
+	}
+
+	int16 DecodeSample(uint8 adpcm)
+	{
+		uint16 step = StepTable[StepIndex];
+
+		if (adpcm & 4)
+			StepIndex += ((adpcm & 3) + 1) * 2;
+		else
+			StepIndex--;
+
+		StepIndex = clamp(StepIndex, 0, 88);
+
+		int delta = step >> 3;
+		if (adpcm & 1) delta += step >> 2;
+		if (adpcm & 2) delta += step >> 1;
+		if (adpcm & 4) delta += step;
+		if (adpcm & 8) delta = -delta;
+
+		int newSample = Sample + delta;
+		Sample = clamp(newSample, -32768, 32767);
+		return Sample;
+	}
+};
+
+class CWavFile : public IDecoder
+{
+	enum
+	{
+		WAVEFMT_PCM = 1,
+		WAVEFMT_IMA_ADPCM = 0x11,
+		WAVEFMT_XBOX_ADPCM = 0x69,
+	};
+
+	struct tDataHeader
+	{
+		uint32 ID;
+		uint32 Size;
+	};
+
+	struct tFormatHeader
+	{
+		uint16 AudioFormat;
+		uint16 NumChannels;
+		uint32 SampleRate;
+		uint32 ByteRate;
+		uint16 BlockAlign;
+		uint16 BitsPerSample;
+		uint16 extra[2]; // adpcm only
+
+		tFormatHeader() { memset(this, 0, sizeof(*this)); }
+	};
+
+	FILE *m_pFile;
+	bool  m_bIsOpen;
+
+	tFormatHeader m_FormatHeader;
+
+	uint32 m_DataStartOffset; // TODO: 64 bit?
+	uint32 m_nSampleCount;
+	uint32 m_nSamplesPerBlock;
+
+	// ADPCM things
+	uint8            *m_pAdpcmBuffer;
+	int16           **m_ppPcmBuffers;
+	CImaADPCMDecoder *m_pAdpcmDecoders;
+
+	void Close()
+	{
+		if (m_pFile) {
+			fclose(m_pFile);
+			m_pFile = nil;
+		}
+		delete[] m_pAdpcmBuffer;
+		delete[] m_ppPcmBuffers;
+		delete[] m_pAdpcmDecoders;
+	}
+
+	uint32 GetCurrentSample() const
+	{
+		// TODO: 64 bit?
+		uint32 FilePos = ftell(m_pFile);
+		if (FilePos <= m_DataStartOffset)
+			return 0;
+		return (FilePos - m_DataStartOffset) / m_FormatHeader.BlockAlign * m_nSamplesPerBlock;
+	}
+
+public:
+	CWavFile(const char* path) : m_bIsOpen(false), m_DataStartOffset(0), m_nSampleCount(0), m_nSamplesPerBlock(0), m_pAdpcmBuffer(nil), m_ppPcmBuffers(nil), m_pAdpcmDecoders(nil)
+	{
+		m_pFile = fopen(path, "rb");
+		if (!m_pFile) return;
+
+#define CLOSE_ON_ERROR(op)\
+			if (op) { \
+				Close(); \
+				return; \
+			}
+
+		tDataHeader DataHeader;
+
+		CLOSE_ON_ERROR(fread(&DataHeader, sizeof(DataHeader), 1, m_pFile) == 0);
+		CLOSE_ON_ERROR(DataHeader.ID != 'FFIR');
+
+		// TODO? validate filesizes
+
+		int WAVE;
+		CLOSE_ON_ERROR(fread(&WAVE, 4, 1, m_pFile) == 0);
+		CLOSE_ON_ERROR(WAVE != 'EVAW')
+		CLOSE_ON_ERROR(fread(&DataHeader, sizeof(DataHeader), 1, m_pFile) == 0);
+		CLOSE_ON_ERROR(DataHeader.ID != ' tmf');
+
+		CLOSE_ON_ERROR(fread(&m_FormatHeader, Min(DataHeader.Size, sizeof(tFormatHeader)), 1, m_pFile) == 0);
+		CLOSE_ON_ERROR(DataHeader.Size > sizeof(tFormatHeader));
+
+		switch (m_FormatHeader.AudioFormat)
+		{
+		case WAVEFMT_XBOX_ADPCM:
+			m_FormatHeader.AudioFormat = WAVEFMT_IMA_ADPCM;
+		case WAVEFMT_IMA_ADPCM:
+			m_nSamplesPerBlock = (m_FormatHeader.BlockAlign / m_FormatHeader.NumChannels - 4) * 2 + 1;
+			m_pAdpcmBuffer = new uint8[m_FormatHeader.BlockAlign];
+			m_ppPcmBuffers = new int16*[m_FormatHeader.NumChannels];
+			m_pAdpcmDecoders = new CImaADPCMDecoder[m_FormatHeader.NumChannels];
+			break;
+		case WAVEFMT_PCM:
+			m_nSamplesPerBlock = 1;
+			if (m_FormatHeader.BitsPerSample != 16)
+			{
+				debug("Unsupported PCM (%d bits), only signed 16-bit is supported (%s)\n", m_FormatHeader.BitsPerSample, path);
+				Close();
+				return;
+			}
+			break;
+		default:
+			debug("Unsupported wav format 0x%x (%s)\n", m_FormatHeader.AudioFormat, path);
+			Close();
+			return;
+		}
+
+		while (true) {
+			CLOSE_ON_ERROR(fread(&DataHeader, sizeof(DataHeader), 1, m_pFile) == 0);
+			if (DataHeader.ID == 'atad')
+				break;
+			fseek(m_pFile, DataHeader.Size, SEEK_CUR);
+			// TODO? validate data size
+			// maybe check if there no extreme custom headers that might break this
+		}
+		
+		m_DataStartOffset = ftell(m_pFile);
+		m_nSampleCount = DataHeader.Size / m_FormatHeader.BlockAlign * m_nSamplesPerBlock;
+
+		m_bIsOpen = true;
+#undef CLOSE_ON_ERROR
+	}
+
+	~CWavFile()
+	{
+		Close();
+	}
+
+	bool IsOpened()
+	{
+		return m_bIsOpen;
+	}
+
+	uint32 GetSampleSize()
+	{
+		return sizeof(uint16);
+	}
+
+	uint32 GetSampleCount()
+	{
+		return m_nSampleCount;
+	}
+
+	uint32 GetSampleRate()
+	{
+		return m_FormatHeader.SampleRate;
+	}
+
+	uint32 GetChannels()
+	{
+		return m_FormatHeader.NumChannels;
+	}
+
+	void Seek(uint32 milliseconds)
+	{
+		if (!IsOpened()) return;
+		fseek(m_pFile, m_DataStartOffset + ms2samples(milliseconds) / m_nSamplesPerBlock * m_FormatHeader.BlockAlign, SEEK_SET);
+	}
+
+	uint32 Tell()
+	{
+		if (!IsOpened()) return 0;
+		return samples2ms(GetCurrentSample());
+	}
+
+#define SAMPLES_IN_LINE (8)
+
+	uint32 Decode(void* buffer)
+	{
+		if (!IsOpened()) return 0;
+		
+		if (m_FormatHeader.AudioFormat == WAVEFMT_PCM)
+		{
+			// just read the file and sort the samples
+			uint32 size = fread(buffer, 1, GetBufferSize(), m_pFile);
+			if (m_FormatHeader.NumChannels == 2)
+				SortStereoBuffer.SortStereo(buffer, size);
+			return size;
+		}
+		else if (m_FormatHeader.AudioFormat == WAVEFMT_IMA_ADPCM)
+		{
+			// trim the buffer size if we're at the end of our file
+			uint32 nMaxSamples = GetBufferSamples() / m_FormatHeader.NumChannels;
+			uint32 nSamplesLeft = m_nSampleCount - GetCurrentSample();
+			nMaxSamples = Min(nMaxSamples, nSamplesLeft);
+
+			// align sample count to our block
+			nMaxSamples = nMaxSamples / m_nSamplesPerBlock * m_nSamplesPerBlock;
+
+			// count the size of output buffer
+			uint32 OutBufSizePerChannel = nMaxSamples * GetSampleSize();
+			uint32 OutBufSize = OutBufSizePerChannel * m_FormatHeader.NumChannels;
+
+			// calculate the pointers to individual channel buffers
+			for (uint32 i = 0; i < m_FormatHeader.NumChannels; i++)
+				m_ppPcmBuffers[i] = (int16*)((int8*)buffer + OutBufSizePerChannel * i);
+
+			uint32 samplesRead = 0;
+			while (samplesRead < nMaxSamples)
+			{
+				// read the file
+				uint8 *pAdpcmBuf = m_pAdpcmBuffer;
+				if (fread(m_pAdpcmBuffer, 1, m_FormatHeader.BlockAlign, m_pFile) == 0)
+					return 0;
+
+				// get the first sample in adpcm block and initialise the decoder(s)
+				for (uint32 i = 0; i < m_FormatHeader.NumChannels; i++)
+				{
+					int16 Sample = *(int16*)pAdpcmBuf;
+					pAdpcmBuf += sizeof(int16);
+					int16 Step = *(int16*)pAdpcmBuf;
+					pAdpcmBuf += sizeof(int16);
+					m_pAdpcmDecoders[i].Init(Sample, Step);
+					*(m_ppPcmBuffers[i]) = Sample;
+					m_ppPcmBuffers[i]++;
+				}
+				samplesRead++;
+
+				// decode the rest of the block
+				for (uint32 s = 1; s < m_nSamplesPerBlock; s += SAMPLES_IN_LINE)
+				{
+					for (uint32 i = 0; i < m_FormatHeader.NumChannels; i++)
+					{
+						m_pAdpcmDecoders[i].Decode(pAdpcmBuf, m_ppPcmBuffers[i], SAMPLES_IN_LINE / 2);
+						pAdpcmBuf += SAMPLES_IN_LINE / 2;
+						m_ppPcmBuffers[i] += SAMPLES_IN_LINE;
+					}
+					samplesRead += SAMPLES_IN_LINE;
+				}
+			}
+			return OutBufSize;
+		}
+		return 0;
+	}
+};
+
+#ifdef AUDIO_OAL_USE_SNDFILE
 class CSndFile : public IDecoder
 {
 	SNDFILE *m_pfSound;
@@ -81,9 +452,20 @@ public:
 	uint32 Decode(void *buffer)
 	{
 		if ( !IsOpened() ) return 0;
-		return sf_read_short(m_pfSound, (short *)buffer, GetBufferSamples()) * GetSampleSize();
+
+		size_t size = sf_read_short(m_pfSound, (short*)buffer, GetBufferSamples()) * GetSampleSize();
+		if (GetChannels()==2)
+			SortStereoBuffer.SortStereo(buffer, size);
+		return size;
 	}
 };
+#endif
+
+#ifdef _WIN32
+// fuzzy seek eliminates stutter when playing ADF but spams errors a lot (nothing breaks though)
+#define MP3_USE_FUZZY_SEEK
+#endif // _WIN32
+
 
 class CMP3File : public IDecoder
 {
@@ -108,6 +490,9 @@ public:
 		m_pMH = mpg123_new(nil, nil);
 		if ( m_pMH )
 		{
+#ifdef MP3_USE_FUZZY_SEEK
+			mpg123_param(m_pMH, MPG123_FLAGS, MPG123_FUZZY | MPG123_SEEKBUFFER | MPG123_GAPLESS, 0.0);
+#endif
 			long rate = 0;
 			int channels = 0;
 			int encoding = 0;
@@ -183,9 +568,249 @@ public:
 		assert("We can't handle audio files more then 2 GB yet :shrug:" && (size < UINT32_MAX));
 #endif
 		if (err != MPG123_OK && err != MPG123_DONE) return 0;
+		if (GetChannels() == 2)
+			SortStereoBuffer.SortStereo(buffer, size);
 		return (uint32)size;
 	}
 };
+
+#define VAG_LINE_SIZE (0x10)
+#define VAG_SAMPLES_IN_LINE (28)
+
+class CVagDecoder
+{
+	const double f[5][2] = { { 0.0, 0.0 },
+					{  60.0 / 64.0,  0.0 },
+					{  115.0 / 64.0, -52.0 / 64.0 },
+					{  98.0 / 64.0, -55.0 / 64.0 },
+					{  122.0 / 64.0, -60.0 / 64.0 } };
+
+	double s_1;
+	double s_2;
+public:
+	CVagDecoder()
+	{
+		ResetState();
+	}
+
+	void ResetState()
+	{
+		s_1 = s_2 = 0.0;
+	}
+
+	static short quantize(double sample)
+	{
+		int a = int(sample + 0.5);
+		return short(clamp(a, -32768, 32767));
+	}
+
+	void Decode(void* _inbuf, int16* _outbuf, size_t size)
+	{
+		uint8* inbuf = (uint8*)_inbuf;
+		int16* outbuf = _outbuf;
+		size &= ~(VAG_LINE_SIZE - 1);
+
+		while (size > 0) {
+			double samples[VAG_SAMPLES_IN_LINE];
+
+			int predict_nr, shift_factor, flags;
+			predict_nr = *(inbuf++);
+			shift_factor = predict_nr & 0xf;
+			predict_nr >>= 4;
+			flags = *(inbuf++);
+			if (flags == 7) // TODO: ignore?
+				break;
+			for (int i = 0; i < VAG_SAMPLES_IN_LINE; i += 2) {
+				int d = *(inbuf++);
+				int16 s = int16((d & 0xf) << 12);
+				samples[i] = (double)(s >> shift_factor);
+				s = int16((d & 0xf0) << 8);
+				samples[i + 1] = (double)(s >> shift_factor);
+			}
+
+			for (int i = 0; i < VAG_SAMPLES_IN_LINE; i++) {
+				samples[i] = samples[i] + s_1 * f[predict_nr][0] + s_2 * f[predict_nr][1];
+				s_2 = s_1;
+				s_1 = samples[i];
+				*(outbuf++) = quantize(samples[i] + 0.5);
+			}
+			size -= VAG_LINE_SIZE;
+		}
+	}
+};
+
+#define VB_BLOCK_SIZE (0x2000)
+#define NUM_VAG_LINES_IN_BLOCK (VB_BLOCK_SIZE / VAG_LINE_SIZE)
+#define NUM_VAG_SAMPLES_IN_BLOCK (NUM_VAG_LINES_IN_BLOCK * VAG_SAMPLES_IN_LINE)
+
+class CVbFile : public IDecoder
+{
+	FILE        *m_pFile;
+	CVagDecoder *m_pVagDecoders;
+
+	size_t  m_FileSize;
+	size_t  m_nNumberOfBlocks;
+
+	uint32  m_nSampleRate;
+	uint8   m_nChannels;
+	bool    m_bBlockRead;
+	uint16  m_LineInBlock;
+	size_t  m_CurrentBlock;
+
+	uint8 **m_ppVagBuffers; // buffers that cache actual ADPCM file data
+	int16 **m_ppPcmBuffers;
+
+	void ReadBlock(int32 block = -1)
+	{
+		// just read next block if -1
+		if (block != -1)
+			fseek(m_pFile, block * m_nChannels * VB_BLOCK_SIZE, SEEK_SET);
+
+		for (int i = 0; i < m_nChannels; i++)
+			fread(m_ppVagBuffers[i], VB_BLOCK_SIZE, 1, m_pFile);
+		m_bBlockRead = true;
+	}
+
+public:
+	CVbFile(const char* path, uint32 nSampleRate = 32000, uint8 nChannels = 2) : m_nSampleRate(nSampleRate), m_nChannels(nChannels), m_pVagDecoders(nil), m_ppVagBuffers(nil), m_ppPcmBuffers(nil),
+		m_FileSize(0), m_nNumberOfBlocks(0), m_bBlockRead(false), m_LineInBlock(0), m_CurrentBlock(0)
+	{
+		m_pFile = fopen(path, "rb");
+		if (!m_pFile) return;
+
+		fseek(m_pFile, 0, SEEK_END);
+		m_FileSize = ftell(m_pFile);
+		fseek(m_pFile, 0, SEEK_SET);
+
+		m_nNumberOfBlocks = m_FileSize / (nChannels * VB_BLOCK_SIZE);
+		m_pVagDecoders = new CVagDecoder[nChannels];
+		m_ppVagBuffers = new uint8*[nChannels];
+		m_ppPcmBuffers = new int16*[nChannels];
+		for (uint8 i = 0; i < nChannels; i++)
+			m_ppVagBuffers[i] = new uint8[VB_BLOCK_SIZE];
+	}
+
+	~CVbFile()
+	{
+		if (m_pFile)
+		{
+			fclose(m_pFile);
+
+			delete[] m_pVagDecoders;
+			for (int i = 0; i < m_nChannels; i++)
+				delete[] m_ppVagBuffers[i];
+			delete[] m_ppVagBuffers;
+			delete[] m_ppPcmBuffers;
+		}
+	}
+
+	bool IsOpened()
+	{
+		return m_pFile != nil;
+	}
+
+	uint32 GetSampleSize()
+	{
+		return sizeof(uint16);
+	}
+
+	uint32 GetSampleCount()
+	{
+		if (!IsOpened()) return 0;
+		return m_nNumberOfBlocks * NUM_VAG_LINES_IN_BLOCK * VAG_SAMPLES_IN_LINE;
+	}
+
+	uint32 GetSampleRate()
+	{
+		return m_nSampleRate;
+	}
+
+	uint32 GetChannels()
+	{
+		return m_nChannels;
+	}
+
+	void Seek(uint32 milliseconds)
+	{
+		if (!IsOpened()) return;
+		uint32 samples = ms2samples(milliseconds);
+
+		// find the block of our sample
+		uint32 block = samples / NUM_VAG_SAMPLES_IN_BLOCK;
+		if (block > m_nNumberOfBlocks)
+		{
+			samples = 0;
+			block = 0;
+		}
+		if (block != m_CurrentBlock)
+			m_bBlockRead = false;
+
+		// find a line of our sample within our block
+		uint32 remainingSamples = samples - block * NUM_VAG_SAMPLES_IN_BLOCK;
+		uint32 newLine = remainingSamples / VAG_SAMPLES_IN_LINE / VAG_LINE_SIZE;
+
+		if (m_CurrentBlock != block || m_LineInBlock != newLine)
+		{
+			m_CurrentBlock = block;
+			m_LineInBlock = newLine;
+			for (uint32 i = 0; i < GetChannels(); i++)
+				m_pVagDecoders[i].ResetState();
+		}
+
+	}
+
+	uint32 Tell()
+	{
+		if (!IsOpened()) return 0;
+		uint32 pos = (m_CurrentBlock * NUM_VAG_LINES_IN_BLOCK + m_LineInBlock) * VAG_SAMPLES_IN_LINE;
+		return samples2ms(pos);
+	}
+
+	uint32 Decode(void* buffer)
+	{
+		if (!IsOpened()) return 0;
+
+		if (m_CurrentBlock >= m_nNumberOfBlocks) return 0;
+
+		// cache current ADPCM block
+		if (!m_bBlockRead)
+			ReadBlock(m_CurrentBlock);
+
+		// trim the buffer size if we're at the end of our file
+		int numberOfRequiredLines = GetBufferSamples() / m_nChannels / VAG_SAMPLES_IN_LINE;
+		int numberOfRemainingLines = (m_nNumberOfBlocks - m_CurrentBlock) * NUM_VAG_LINES_IN_BLOCK - m_LineInBlock;
+		int bufSizePerChannel = Min(numberOfRequiredLines, numberOfRemainingLines) * VAG_SAMPLES_IN_LINE * GetSampleSize();
+
+		// calculate the pointers to individual channel buffers
+		for (uint32 i = 0; i < m_nChannels; i++)
+			m_ppPcmBuffers[i] = (int16*)((int8*)buffer + bufSizePerChannel * i);
+
+		int size = 0;
+		while (size < bufSizePerChannel)
+		{
+			// decode the VAG lines
+			for (uint32 i = 0; i < m_nChannels; i++)
+			{
+				m_pVagDecoders[i].Decode(m_ppVagBuffers[i] + m_LineInBlock * VAG_LINE_SIZE, m_ppPcmBuffers[i], VAG_LINE_SIZE);
+				m_ppPcmBuffers[i] += VAG_SAMPLES_IN_LINE;
+			}
+			size += VAG_SAMPLES_IN_LINE * GetSampleSize();
+			m_LineInBlock++;
+
+			// block is over, read the next block
+			if (m_LineInBlock >= NUM_VAG_LINES_IN_BLOCK)
+			{
+				m_CurrentBlock++;
+				if (m_CurrentBlock >= m_nNumberOfBlocks) // end of file
+					break;
+				m_LineInBlock = 0;
+				ReadBlock();
+			}
+		}
+
+		return bufSizePerChannel * m_nChannels;
+	}
+};
 #else
 class COpusFile : public IDecoder
 {
@@ -274,6 +899,9 @@ public:
 		if (size < 0)
 			return 0;
 
+		if (GetChannels() == 2)
+			SortStereoBuffer.SortStereo(buffer, size * m_nChannels * GetSampleSize());
+
 		return size * m_nChannels * GetSampleSize();
 	}
 };
@@ -285,7 +913,7 @@ class CADFFile : public CMP3File
 	{
 		size_t bytesRead = fread(buf, 1, size, (FILE*)fh);
 		uint8* _buf = (uint8*)buf;
-		for (int i = 0; i < size; i++)
+		for (size_t i = 0; i < size; i++)
 			_buf[i] ^= 0x22;
 		return bytesRead;
 	}
@@ -304,6 +932,9 @@ public:
 		m_pMH = mpg123_new(nil, nil);
 		if (m_pMH)
 		{
+#ifdef MP3_USE_FUZZY_SEEK
+			mpg123_param(m_pMH, MPG123_FLAGS, MPG123_FUZZY | MPG123_SEEKBUFFER | MPG123_GAPLESS, 0.0);
+#endif
 			long rate = 0;
 			int channels = 0;
 			int encoding = 0;
@@ -338,8 +969,8 @@ void CStream::Terminate()
 #endif
 }
 
-CStream::CStream(char *filename, ALuint &source, ALuint (&buffers)[NUM_STREAMBUFFERS]) :
-	m_alSource(source),
+CStream::CStream(char *filename, ALuint *sources, ALuint (&buffers)[NUM_STREAMBUFFERS], uint32 overrideSampleRate) :
+	m_pAlSources(sources),
 	m_alBuffers(buffers),
 	m_pBuffer(nil),
 	m_bPaused(false),
@@ -370,9 +1001,15 @@ CStream::CStream(char *filename, ALuint &source, ALuint (&buffers)[NUM_STREAMBUF
 	if (!strcasecmp(&m_aFilename[strlen(m_aFilename) - strlen(".mp3")], ".mp3"))
 		m_pSoundFile = new CMP3File(m_aFilename);
 	else if (!strcasecmp(&m_aFilename[strlen(m_aFilename) - strlen(".wav")], ".wav"))
+#ifdef AUDIO_OAL_USE_SNDFILE
 		m_pSoundFile = new CSndFile(m_aFilename);
+#else
+		m_pSoundFile = new CWavFile(m_aFilename);
+#endif
 	else if (!strcasecmp(&m_aFilename[strlen(m_aFilename) - strlen(".adf")], ".adf"))
 		m_pSoundFile = new CADFFile(m_aFilename);
+	else if (!strcasecmp(&m_aFilename[strlen(m_aFilename) - strlen(".vb")], ".VB"))
+		m_pSoundFile = new CVbFile(m_aFilename, overrideSampleRate);
 #else
 	if (!strcasecmp(&m_aFilename[strlen(m_aFilename) - strlen(".opus")], ".opus"))
 		m_pSoundFile = new COpusFile(m_aFilename);
@@ -422,7 +1059,7 @@ void CStream::Delete()
 
 bool CStream::HasSource()
 {
-	return m_alSource != AL_NONE;
+	return (m_pAlSources[0] != AL_NONE) && (m_pAlSources[1] != AL_NONE);
 }
 
 bool CStream::IsOpened()
@@ -436,9 +1073,10 @@ bool CStream::IsPlaying()
 	
 	if ( !m_bPaused )
 	{
-		ALint sourceState;
-		alGetSourcei(m_alSource, AL_SOURCE_STATE, &sourceState);
-		if ( m_bActive || sourceState == AL_PLAYING )
+		ALint sourceState[2];
+		alGetSourcei(m_pAlSources[0], AL_SOURCE_STATE, &sourceState[0]);
+		alGetSourcei(m_pAlSources[1], AL_SOURCE_STATE, &sourceState[1]);
+		if ( m_bActive || sourceState[0] == AL_PLAYING || sourceState[1] == AL_PLAYING)
 			return true;
 	}
 	
@@ -449,9 +1087,12 @@ void CStream::Pause()
 {
 	if ( !HasSource() ) return;
 	ALint sourceState = AL_PAUSED;
-	alGetSourcei(m_alSource, AL_SOURCE_STATE, &sourceState);
-	if (sourceState != AL_PAUSED )
-		alSourcePause(m_alSource);
+	alGetSourcei(m_pAlSources[0], AL_SOURCE_STATE, &sourceState);
+	if (sourceState != AL_PAUSED)
+		alSourcePause(m_pAlSources[0]);
+	alGetSourcei(m_pAlSources[1], AL_SOURCE_STATE, &sourceState);
+	if (sourceState != AL_PAUSED)
+		alSourcePause(m_pAlSources[1]);
 }
 
 void CStream::SetPause(bool bPause)
@@ -473,19 +1114,21 @@ void CStream::SetPause(bool bPause)
 void CStream::SetPitch(float pitch)
 {
 	if ( !HasSource() ) return;
-	alSourcef(m_alSource, AL_PITCH, pitch);
+	alSourcef(m_pAlSources[0], AL_PITCH, pitch);
+	alSourcef(m_pAlSources[1], AL_PITCH, pitch);
 }
 
 void CStream::SetGain(float gain)
 {
 	if ( !HasSource() ) return;
-	alSourcef(m_alSource, AL_GAIN, gain);
+	alSourcef(m_pAlSources[0], AL_GAIN, gain);
+	alSourcef(m_pAlSources[1], AL_GAIN, gain);
 }
 
-void CStream::SetPosition(float x, float y, float z)
+void CStream::SetPosition(int i, float x, float y, float z)
 {
 	if ( !HasSource() ) return;
-	alSource3f(m_alSource, AL_POSITION, x, y, z);
+	alSource3f(m_pAlSources[i], AL_POSITION, x, y, z);
 }
 
 void CStream::SetVolume(uint32 nVol)
@@ -496,8 +1139,13 @@ void CStream::SetVolume(uint32 nVol)
 
 void CStream::SetPan(uint8 nPan)
 {
+	m_nPan = clamp((int8)nPan - 63, 0, 63);
+	SetPosition(0, (m_nPan - 63) / 64.0f, 0.0f, Sqrt(1.0f - SQR((m_nPan - 63) / 64.0f)));
+
+	m_nPan = clamp((int8)nPan + 64, 64, 127);
+	SetPosition(1, (m_nPan - 63) / 64.0f, 0.0f, Sqrt(1.0f - SQR((m_nPan - 63) / 64.0f)));
+
 	m_nPan = nPan;
-	SetPosition((nPan - 63)/64.0f, 0.0f, Sqrt(1.0f-SQR((nPan-63)/64.0f)));
 }
 
 void CStream::SetPosMS(uint32 nPos)
@@ -514,10 +1162,10 @@ uint32 CStream::GetPosMS()
 	
 	ALint offset;
 	//alGetSourcei(m_alSource, AL_SAMPLE_OFFSET, &offset);
-	alGetSourcei(m_alSource, AL_BYTE_OFFSET, &offset);
+	alGetSourcei(m_pAlSources[0], AL_BYTE_OFFSET, &offset);
 
 	return m_pSoundFile->Tell()
-		- m_pSoundFile->samples2ms(m_pSoundFile->GetBufferSamples() * (NUM_STREAMBUFFERS-1)) / m_pSoundFile->GetChannels()
+		- m_pSoundFile->samples2ms(m_pSoundFile->GetBufferSamples() * (NUM_STREAMBUFFERS/2-1)) / m_pSoundFile->GetChannels()
 		+ m_pSoundFile->samples2ms(offset/m_pSoundFile->GetSampleSize()) / m_pSoundFile->GetChannels();
 }
 
@@ -527,33 +1175,41 @@ uint32 CStream::GetLengthMS()
 	return m_pSoundFile->GetLength();
 }
 
-bool CStream::FillBuffer(ALuint alBuffer)
+bool CStream::FillBuffer(ALuint *alBuffer)
 {
 	if ( !HasSource() )
 		return false;
 	if ( !IsOpened() )
 		return false;
-	if ( !(alBuffer != AL_NONE && alIsBuffer(alBuffer)) )
+	if ( !(alBuffer[0] != AL_NONE && alIsBuffer(alBuffer[0])) )
+		return false;
+	if ( !(alBuffer[1] != AL_NONE && alIsBuffer(alBuffer[1])) )
 		return false;
 	
 	uint32 size = m_pSoundFile->Decode(m_pBuffer);
 	if( size == 0 )
 		return false;
 	
-	alBufferData(alBuffer, m_pSoundFile->GetChannels() == 1 ? AL_FORMAT_MONO16 : AL_FORMAT_STEREO16,
-		m_pBuffer, size, m_pSoundFile->GetSampleRate());
-	
+	uint32 channelSize = size / m_pSoundFile->GetChannels();
+
+	alBufferData(alBuffer[0], AL_FORMAT_MONO16, m_pBuffer, channelSize, m_pSoundFile->GetSampleRate());
+	// TODO: use just one buffer if we play mono
+	if (m_pSoundFile->GetChannels() == 1)
+		alBufferData(alBuffer[1], AL_FORMAT_MONO16, m_pBuffer, channelSize, m_pSoundFile->GetSampleRate());
+	else
+		alBufferData(alBuffer[1], AL_FORMAT_MONO16, (uint8*)m_pBuffer + channelSize, channelSize, m_pSoundFile->GetSampleRate());
 	return true;
 }
 
 int32 CStream::FillBuffers()
 {
 	int32 i = 0;
-	for ( i = 0; i < NUM_STREAMBUFFERS; i++ )
+	for ( i = 0; i < NUM_STREAMBUFFERS/2; i++ )
 	{
-		if ( !FillBuffer(m_alBuffers[i]) )
+		if ( !FillBuffer(&m_alBuffers[i*2]) )
 			break;
-		alSourceQueueBuffers(m_alSource, 1, &m_alBuffers[i]);
+		alSourceQueueBuffers(m_pAlSources[0], 1, &m_alBuffers[i*2]);
+		alSourceQueueBuffers(m_pAlSources[1], 1, &m_alBuffers[i*2+1]);
 	}
 	
 	return i;
@@ -563,12 +1219,15 @@ void CStream::ClearBuffers()
 {
 	if ( !HasSource() ) return;
 	
-	ALint buffersQueued;
-	alGetSourcei(m_alSource, AL_BUFFERS_QUEUED, &buffersQueued);
+	ALint buffersQueued[2];
+	alGetSourcei(m_pAlSources[0], AL_BUFFERS_QUEUED, &buffersQueued[0]);
+	alGetSourcei(m_pAlSources[1], AL_BUFFERS_QUEUED, &buffersQueued[1]);
 
 	ALuint value;
-	while (buffersQueued--)
-		alSourceUnqueueBuffers(m_alSource, 1, &value);
+	while (buffersQueued[0]--)
+		alSourceUnqueueBuffers(m_pAlSources[0], 1, &value);
+	while (buffersQueued[1]--)
+		alSourceUnqueueBuffers(m_pAlSources[1], 1, &value);
 }
 
 bool CStream::Setup()
@@ -576,7 +1235,6 @@ bool CStream::Setup()
 	if ( IsOpened() )
 	{
 		m_pSoundFile->Seek(0);
-		alSourcei(m_alSource, AL_SOURCE_RELATIVE, AL_TRUE);
 		//SetPosition(0.0f, 0.0f, 0.0f);
 		SetPitch(1.0f);
 		//SetPan(m_nPan);
@@ -592,17 +1250,29 @@ void CStream::SetPlay(bool state)
 	if ( state )
 	{
 		ALint sourceState = AL_PLAYING;
-		alGetSourcei(m_alSource, AL_SOURCE_STATE, &sourceState);
+		alGetSourcei(m_pAlSources[0], AL_SOURCE_STATE, &sourceState);
 		if (sourceState != AL_PLAYING )
-			alSourcePlay(m_alSource);
+			alSourcePlay(m_pAlSources[0]);
+
+		sourceState = AL_PLAYING;
+		alGetSourcei(m_pAlSources[1], AL_SOURCE_STATE, &sourceState);
+		if (sourceState != AL_PLAYING)
+			alSourcePlay(m_pAlSources[1]);
+
 		m_bActive = true;
 	}
 	else
 	{
 		ALint sourceState = AL_STOPPED;
-		alGetSourcei(m_alSource, AL_SOURCE_STATE, &sourceState);
+		alGetSourcei(m_pAlSources[0], AL_SOURCE_STATE, &sourceState);
 		if (sourceState != AL_STOPPED )
-			alSourceStop(m_alSource);
+			alSourceStop(m_pAlSources[0]);
+
+		sourceState = AL_STOPPED;
+		alGetSourcei(m_pAlSources[1], AL_SOURCE_STATE, &sourceState);
+		if (sourceState != AL_STOPPED)
+			alSourceStop(m_pAlSources[1]);
+
 		m_bActive = false;
 	}
 }
@@ -633,35 +1303,51 @@ void CStream::Update()
 	
 	if ( !m_bPaused )
 	{
-		ALint sourceState;
-		ALint buffersProcessed = 0;
+		ALint sourceState[2];
+		ALint buffersProcessed[2] = { 0, 0 };
 		
-		alGetSourcei(m_alSource, AL_SOURCE_STATE, &sourceState);
-		alGetSourcei(m_alSource, AL_BUFFERS_PROCESSED, &buffersProcessed);
+		// Relying a lot on left buffer states in here
+
+		do
+		{
+			//alSourcef(m_pAlSources[0], AL_ROLLOFF_FACTOR, 0.0f);
+			alGetSourcei(m_pAlSources[0], AL_SOURCE_STATE, &sourceState[0]);
+			alGetSourcei(m_pAlSources[0], AL_BUFFERS_PROCESSED, &buffersProcessed[0]);
+			//alSourcef(m_pAlSources[1], AL_ROLLOFF_FACTOR, 0.0f);
+			alGetSourcei(m_pAlSources[1], AL_SOURCE_STATE, &sourceState[1]);
+			alGetSourcei(m_pAlSources[1], AL_BUFFERS_PROCESSED, &buffersProcessed[1]);
+		} while (buffersProcessed[0] != buffersProcessed[1]);
 		
 		ALint looping = AL_FALSE;
-		alGetSourcei(m_alSource, AL_LOOPING, &looping);
+		alGetSourcei(m_pAlSources[0], AL_LOOPING, &looping);
 		
 		if ( looping == AL_TRUE )
 		{
 			TRACE("stream set looping");
-			alSourcei(m_alSource, AL_LOOPING, AL_TRUE);
+			alSourcei(m_pAlSources[0], AL_LOOPING, AL_TRUE);
+			alSourcei(m_pAlSources[1], AL_LOOPING, AL_TRUE);
 		}
 		
-		while( buffersProcessed-- )
+		assert(buffersProcessed[0] == buffersProcessed[1]);
+
+		while( buffersProcessed[0]-- )
 		{
-			ALuint buffer;
+			ALuint buffer[2];
 			
-			alSourceUnqueueBuffers(m_alSource, 1, &buffer);
+			alSourceUnqueueBuffers(m_pAlSources[0], 1, &buffer[0]);
+			alSourceUnqueueBuffers(m_pAlSources[1], 1, &buffer[1]);
 			
-			if ( m_bActive && FillBuffer(buffer) )
-				alSourceQueueBuffers(m_alSource, 1, &buffer);
+			if (m_bActive && FillBuffer(buffer))
+			{
+				alSourceQueueBuffers(m_pAlSources[0], 1, &buffer[0]);
+				alSourceQueueBuffers(m_pAlSources[1], 1, &buffer[1]);
+			}
 		}
 		
-		if ( sourceState != AL_PLAYING )
+		if ( sourceState[0] != AL_PLAYING )
 		{
-			alGetSourcei(m_alSource, AL_BUFFERS_PROCESSED, &buffersProcessed);
-			SetPlay(buffersProcessed!=0);
+			alGetSourcei(m_pAlSources[0], AL_BUFFERS_PROCESSED, &buffersProcessed[0]);
+			SetPlay(buffersProcessed[0]!=0);
 		}
 	}
 }
diff --git a/src/audio/oal/stream.h b/src/audio/oal/stream.h
index 2476abcc..bcbc5e54 100644
--- a/src/audio/oal/stream.h
+++ b/src/audio/oal/stream.h
@@ -3,7 +3,7 @@
 #ifdef AUDIO_OAL
 #include <AL/al.h>
 
-#define NUM_STREAMBUFFERS 4
+#define NUM_STREAMBUFFERS 8
 
 class IDecoder
 {
@@ -57,7 +57,7 @@ public:
 class CStream
 {
 	char     m_aFilename[128];
-	ALuint  &m_alSource;
+	ALuint  *m_pAlSources;
 	ALuint (&m_alBuffers)[NUM_STREAMBUFFERS];
 	
 	bool     m_bPaused;
@@ -73,20 +73,20 @@ class CStream
 	IDecoder *m_pSoundFile;
 	
 	bool HasSource();
-	void SetPosition(float x, float y, float z);
+	void SetPosition(int i, float x, float y, float z);
 	void SetPitch(float pitch);
 	void SetGain(float gain);
 	void   Pause();
 	void   SetPlay(bool state);
 	
-	bool   FillBuffer(ALuint alBuffer);
+	bool   FillBuffer(ALuint *alBuffer);
 	int32  FillBuffers();
 	void   ClearBuffers();
 public:
 	static void Initialise();
 	static void Terminate();
 	
-	CStream(char *filename, ALuint &source, ALuint (&buffers)[NUM_STREAMBUFFERS]);
+	CStream(char *filename, ALuint *sources, ALuint (&buffers)[NUM_STREAMBUFFERS], uint32 overrideSampleRate = 32000);
 	~CStream();
 	void   Delete();