AuroraOpenALSoft/Alc/mixer.c
2012-09-14 04:16:49 -07:00

439 lines
14 KiB
C

/**
* OpenAL cross platform audio library
* Copyright (C) 1999-2007 by authors.
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
* Or go to http://www.gnu.org/copyleft/lgpl.html
*/
#include "config.h"
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <assert.h>
#include "alMain.h"
#include "AL/al.h"
#include "AL/alc.h"
#include "alSource.h"
#include "alBuffer.h"
#include "alListener.h"
#include "alAuxEffectSlot.h"
#include "alu.h"
#include "bs2b.h"
static __inline ALfloat Sample_ALbyte(ALbyte val)
{ return val * (1.0f/127.0f); }
static __inline ALfloat Sample_ALshort(ALshort val)
{ return val * (1.0f/32767.0f); }
static __inline ALfloat Sample_ALfloat(ALfloat val)
{ return val; }
#define DECL_TEMPLATE(T) \
static void Load_##T(ALfloat *dst, const T *src, ALuint samples) \
{ \
ALuint i; \
for(i = 0;i < samples;i++) \
dst[i] = Sample_##T(src[i]); \
}
DECL_TEMPLATE(ALbyte)
DECL_TEMPLATE(ALshort)
DECL_TEMPLATE(ALfloat)
#undef DECL_TEMPLATE
static void LoadStack(ALfloat *dst, const ALvoid *src, enum FmtType srctype, ALuint samples)
{
switch(srctype)
{
case FmtByte:
Load_ALbyte(dst, src, samples);
break;
case FmtShort:
Load_ALshort(dst, src, samples);
break;
case FmtFloat:
Load_ALfloat(dst, src, samples);
break;
}
}
static void SilenceStack(ALfloat *dst, ALuint samples)
{
ALuint i;
for(i = 0;i < samples;i++)
dst[i] = 0.0f;
}
static void Filter2P(FILTER *filter, ALuint chan, ALfloat *RESTRICT dst,
const ALfloat *RESTRICT src, ALuint numsamples)
{
ALuint i;
for(i = 0;i < numsamples;i++)
dst[i] = lpFilter2P(filter, chan, src[i]);
dst[i] = lpFilter2PC(filter, chan, src[i]);
}
ALvoid MixSource(ALsource *Source, ALCdevice *Device, ALuint SamplesToDo)
{
ALbufferlistitem *BufferListItem;
ALuint DataPosInt, DataPosFrac;
ALuint BuffersPlayed;
ALboolean Looping;
ALuint increment;
enum Resampler Resampler;
ALenum State;
ALuint OutPos;
ALuint NumChannels;
ALuint FrameSize;
ALint64 DataSize64;
ALuint i, j;
/* Get source info */
State = Source->state;
BuffersPlayed = Source->BuffersPlayed;
DataPosInt = Source->position;
DataPosFrac = Source->position_fraction;
Looping = Source->Looping;
increment = Source->Params.Step;
Resampler = Source->Resampler;
NumChannels = Source->NumChannels;
FrameSize = NumChannels * Source->SampleSize;
/* Get current buffer queue item */
BufferListItem = Source->queue;
for(i = 0;i < BuffersPlayed;i++)
BufferListItem = BufferListItem->next;
OutPos = 0;
do {
const ALuint BufferPrePadding = ResamplerPrePadding[Resampler];
const ALuint BufferPadding = ResamplerPadding[Resampler];
ALfloat StackData[BUFFERSIZE];
ALfloat *SrcData = StackData;
ALuint SrcDataSize = 0;
ALuint BufferSize;
/* Figure out how many buffer bytes will be needed */
DataSize64 = SamplesToDo-OutPos+1;
DataSize64 *= increment;
DataSize64 += DataPosFrac+FRACTIONMASK;
DataSize64 >>= FRACTIONBITS;
DataSize64 += BufferPadding+BufferPrePadding;
DataSize64 *= NumChannels;
BufferSize = (ALuint)mini64(DataSize64, BUFFERSIZE);
BufferSize /= NumChannels;
if(Source->SourceType == AL_STATIC)
{
const ALbuffer *ALBuffer = Source->queue->buffer;
const ALubyte *Data = ALBuffer->data;
ALuint DataSize;
ALuint pos;
/* If current pos is beyond the loop range, do not loop */
if(Looping == AL_FALSE || DataPosInt >= (ALuint)ALBuffer->LoopEnd)
{
Looping = AL_FALSE;
if(DataPosInt >= BufferPrePadding)
pos = DataPosInt - BufferPrePadding;
else
{
DataSize = BufferPrePadding - DataPosInt;
DataSize = minu(BufferSize, DataSize);
SilenceStack(&SrcData[SrcDataSize*NumChannels],
DataSize*NumChannels);
SrcDataSize += DataSize;
BufferSize -= DataSize;
pos = 0;
}
/* Copy what's left to play in the source buffer, and clear the
* rest of the temp buffer */
DataSize = ALBuffer->SampleLen - pos;
DataSize = minu(BufferSize, DataSize);
LoadStack(&SrcData[SrcDataSize*NumChannels], &Data[pos*FrameSize],
ALBuffer->FmtType, DataSize*NumChannels);
SrcDataSize += DataSize;
BufferSize -= DataSize;
SilenceStack(&SrcData[SrcDataSize*NumChannels],
BufferSize*NumChannels);
SrcDataSize += BufferSize;
BufferSize -= BufferSize;
}
else
{
ALuint LoopStart = ALBuffer->LoopStart;
ALuint LoopEnd = ALBuffer->LoopEnd;
if(DataPosInt >= LoopStart)
{
pos = DataPosInt-LoopStart;
while(pos < BufferPrePadding)
pos += LoopEnd-LoopStart;
pos -= BufferPrePadding;
pos += LoopStart;
}
else if(DataPosInt >= BufferPrePadding)
pos = DataPosInt - BufferPrePadding;
else
{
DataSize = BufferPrePadding - DataPosInt;
DataSize = minu(BufferSize, DataSize);
SilenceStack(&SrcData[SrcDataSize*NumChannels], DataSize*NumChannels);
SrcDataSize += DataSize;
BufferSize -= DataSize;
pos = 0;
}
/* Copy what's left of this loop iteration, then copy repeats
* of the loop section */
DataSize = LoopEnd - pos;
DataSize = minu(BufferSize, DataSize);
LoadStack(&SrcData[SrcDataSize*NumChannels], &Data[pos*FrameSize],
ALBuffer->FmtType, DataSize*NumChannels);
SrcDataSize += DataSize;
BufferSize -= DataSize;
DataSize = LoopEnd-LoopStart;
while(BufferSize > 0)
{
DataSize = minu(BufferSize, DataSize);
LoadStack(&SrcData[SrcDataSize*NumChannels], &Data[LoopStart*FrameSize],
ALBuffer->FmtType, DataSize*NumChannels);
SrcDataSize += DataSize;
BufferSize -= DataSize;
}
}
}
else
{
/* Crawl the buffer queue to fill in the temp buffer */
ALbufferlistitem *tmpiter = BufferListItem;
ALuint pos;
if(DataPosInt >= BufferPrePadding)
pos = DataPosInt - BufferPrePadding;
else
{
pos = BufferPrePadding - DataPosInt;
while(pos > 0)
{
if(!tmpiter->prev && !Looping)
{
ALuint DataSize = minu(BufferSize, pos);
SilenceStack(&SrcData[SrcDataSize*NumChannels], DataSize*NumChannels);
SrcDataSize += DataSize;
BufferSize -= DataSize;
pos = 0;
break;
}
if(tmpiter->prev)
tmpiter = tmpiter->prev;
else
{
while(tmpiter->next)
tmpiter = tmpiter->next;
}
if(tmpiter->buffer)
{
if((ALuint)tmpiter->buffer->SampleLen > pos)
{
pos = tmpiter->buffer->SampleLen - pos;
break;
}
pos -= tmpiter->buffer->SampleLen;
}
}
}
while(tmpiter && BufferSize > 0)
{
const ALbuffer *ALBuffer;
if((ALBuffer=tmpiter->buffer) != NULL)
{
const ALubyte *Data = ALBuffer->data;
ALuint DataSize = ALBuffer->SampleLen;
/* Skip the data already played */
if(DataSize <= pos)
pos -= DataSize;
else
{
Data += pos*FrameSize;
DataSize -= pos;
pos -= pos;
DataSize = minu(BufferSize, DataSize);
LoadStack(&SrcData[SrcDataSize*NumChannels], Data,
ALBuffer->FmtType, DataSize*NumChannels);
SrcDataSize += DataSize;
BufferSize -= DataSize;
}
}
tmpiter = tmpiter->next;
if(!tmpiter && Looping)
tmpiter = Source->queue;
else if(!tmpiter)
{
SilenceStack(&SrcData[SrcDataSize*NumChannels], BufferSize*NumChannels);
SrcDataSize += BufferSize;
BufferSize -= BufferSize;
}
}
}
/* Figure out how many samples we can mix. */
DataSize64 = SrcDataSize;
DataSize64 -= BufferPadding+BufferPrePadding;
DataSize64 <<= FRACTIONBITS;
DataSize64 -= increment;
DataSize64 -= DataPosFrac;
BufferSize = (ALuint)((DataSize64+(increment-1)) / increment);
BufferSize = minu(BufferSize, (SamplesToDo-OutPos));
/* Some mixers like having a multiple of 4, so try to give that unless
* this is the last update. */
if(OutPos+BufferSize < SamplesToDo)
BufferSize &= ~3;
SrcData += BufferPrePadding*NumChannels;
for(i = 0;i < NumChannels;i++)
{
DirectParams *directparms = &Source->Params.Direct;
ALIGN(16) ALfloat FilteredData[BUFFERSIZE];
ALIGN(16) ALfloat ResampledData[BUFFERSIZE];
Source->Params.Resample(SrcData+i, DataPosFrac, increment,
NumChannels, ResampledData, BufferSize);
Filter2P(&directparms->iirFilter, i, FilteredData, ResampledData,
BufferSize);
Source->Params.DryMix(Source, Device, directparms,
FilteredData, i, OutPos, SamplesToDo,
BufferSize);
for(j = 0;j < Device->NumAuxSends;j++)
{
SendParams *sendparms = &Source->Params.Send[j];
if(!sendparms->Slot)
continue;
Filter2P(&sendparms->iirFilter, i, FilteredData, ResampledData,
BufferSize);
Source->Params.WetMix(sendparms, FilteredData, OutPos,
SamplesToDo, BufferSize);
}
}
for(i = 0;i < BufferSize;i++)
{
DataPosFrac += increment;
DataPosInt += DataPosFrac>>FRACTIONBITS;
DataPosFrac &= FRACTIONMASK;
OutPos++;
}
/* Handle looping sources */
while(1)
{
const ALbuffer *ALBuffer;
ALuint DataSize = 0;
ALuint LoopStart = 0;
ALuint LoopEnd = 0;
if((ALBuffer=BufferListItem->buffer) != NULL)
{
DataSize = ALBuffer->SampleLen;
LoopStart = ALBuffer->LoopStart;
LoopEnd = ALBuffer->LoopEnd;
if(LoopEnd > DataPosInt)
break;
}
if(Looping && Source->SourceType == AL_STATIC)
{
DataPosInt = ((DataPosInt-LoopStart)%(LoopEnd-LoopStart)) + LoopStart;
break;
}
if(DataSize > DataPosInt)
break;
if(BufferListItem->next)
{
BufferListItem = BufferListItem->next;
BuffersPlayed++;
}
else if(Looping)
{
BufferListItem = Source->queue;
BuffersPlayed = 0;
}
else
{
State = AL_STOPPED;
BufferListItem = Source->queue;
BuffersPlayed = Source->BuffersInQueue;
DataPosInt = 0;
DataPosFrac = 0;
break;
}
DataPosInt -= DataSize;
}
} while(State == AL_PLAYING && OutPos < SamplesToDo);
/* Update source info */
Source->state = State;
Source->BuffersPlayed = BuffersPlayed;
Source->position = DataPosInt;
Source->position_fraction = DataPosFrac;
Source->Hrtf.Offset += OutPos;
if(State == AL_PLAYING)
{
Source->Hrtf.Counter = maxu(Source->Hrtf.Counter, OutPos) - OutPos;
Source->Hrtf.Moving = AL_TRUE;
}
else
{
Source->Hrtf.Counter = 0;
Source->Hrtf.Moving = AL_FALSE;
}
}