HRESULT DSW_ZeroEmptySpace( DSoundWrapper *dsw )
{
HRESULT hr;
LPBYTE lpbuf1 = NULL;
LPBYTE lpbuf2 = NULL;
DWORD dwsize1 = 0;
DWORD dwsize2 = 0;
long bytesEmpty;
hr = DSW_QueryOutputSpace( dsw, &bytesEmpty ); // updates dsw_FramesPlayed
if (hr != DS_OK) return hr;
if( bytesEmpty == 0 ) return DS_OK;
// Lock free space in the DS
hr = IDirectSoundBuffer_Lock( dsw->dsw_OutputBuffer, dsw->dsw_WriteOffset, bytesEmpty, (void **) &lpbuf1, &dwsize1,
(void **) &lpbuf2, &dwsize2, 0);
if (hr == DS_OK)
{
// Copy the buffer into the DS
ZeroMemory(lpbuf1, dwsize1);
if(lpbuf2 != NULL)
{
ZeroMemory(lpbuf2, dwsize2);
}
// Update our buffer offset and unlock sound buffer
dsw->dsw_WriteOffset = (dsw->dsw_WriteOffset + dwsize1 + dwsize2) % dsw->dsw_OutputSize;
IDirectSoundBuffer_Unlock( dsw->dsw_OutputBuffer, lpbuf1, dwsize1, lpbuf2, dwsize2);
dsw->dsw_FramesWritten += bytesEmpty / dsw->dsw_BytesPerFrame;
}
return hr;
}
static PaError Pa_TimeSlice( internalPortAudioStream *past )
{
PaError result = 0;
long bytesEmpty = 0;
long bytesFilled = 0;
long bytesToXfer = 0;
long numChunks;
HRESULT hresult;
PaHostSoundControl *pahsc;
short *nativeBufPtr;
past->past_NumCallbacks += 1;
pahsc = (PaHostSoundControl *) past->past_DeviceData;
if( pahsc == NULL ) return paInternalError;
/* How much input data is available? */
#if SUPPORT_AUDIO_CAPTURE
if( past->past_NumInputChannels > 0 )
{
DSW_QueryInputFilled( &pahsc->pahsc_DSoundWrapper, &bytesFilled );
bytesToXfer = bytesFilled;
}
#endif /* SUPPORT_AUDIO_CAPTURE */
/* How much output room is available? */
if( past->past_NumOutputChannels > 0 )
{
DSW_QueryOutputSpace( &pahsc->pahsc_DSoundWrapper, &bytesEmpty );
bytesToXfer = bytesEmpty;
}
AddTraceMessage( "bytesEmpty ", bytesEmpty );
/* Choose smallest value if both are active. */
if( (past->past_NumInputChannels > 0) && (past->past_NumOutputChannels > 0) )
{
bytesToXfer = ( bytesFilled < bytesEmpty ) ? bytesFilled : bytesEmpty;
}
/* printf("bytesFilled = %d, bytesEmpty = %d, bytesToXfer = %d\n",
bytesFilled, bytesEmpty, bytesToXfer);
*/
/* Quantize to multiples of a buffer. */
numChunks = bytesToXfer / pahsc->pahsc_BytesPerBuffer;
if( numChunks > (long)(past->past_NumUserBuffers/2) )
{
numChunks = (long)past->past_NumUserBuffers/2;
}
else if( numChunks < 0 )
{
numChunks = 0;
}
AddTraceMessage( "numChunks ", numChunks );
nativeBufPtr = pahsc->pahsc_NativeBuffer;
if( numChunks > 0 )
{
while( numChunks-- > 0 )
{
/* Measure usage based on time to process one user buffer. */
Pa_StartUsageCalculation( past );
#if SUPPORT_AUDIO_CAPTURE
/* Get native data from DirectSound. */
if( past->past_NumInputChannels > 0 )
{
hresult = DSW_ReadBlock( &pahsc->pahsc_DSoundWrapper, (char *) nativeBufPtr, pahsc->pahsc_BytesPerBuffer );
if( hresult < 0 )
{
ERR_RPT(("DirectSound ReadBlock failed, hresult = 0x%x\n",hresult));
sPaHostError = hresult;
break;
}
}
#endif /* SUPPORT_AUDIO_CAPTURE */
/* Convert 16 bit native data to user data and call user routine. */
result = Pa_CallConvertInt16( past, nativeBufPtr, nativeBufPtr );
if( result != 0) break;
/* Pass native data to DirectSound. */
if( past->past_NumOutputChannels > 0 )
{
/* static short DEBUGHACK = 0;
DEBUGHACK += 0x0049;
nativeBufPtr[0] = DEBUGHACK; /* Make buzz to see if DirectSound still running. */
hresult = DSW_WriteBlock( &pahsc->pahsc_DSoundWrapper, (char *) nativeBufPtr, pahsc->pahsc_BytesPerBuffer );
if( hresult < 0 )
{
ERR_RPT(("DirectSound WriteBlock failed, result = 0x%x\n",hresult));
sPaHostError = hresult;
break;
}
}
Pa_EndUsageCalculation( past );
}
}
return result;
}
