Alc/mixer.c

   1 /**
   2  * OpenAL cross platform audio library
   3  * Copyright (C) 1999-2007 by authors.
   4  * This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Library General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  *  License along with this library; if not, write to the
  16  *  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  *  Boston, MA  02111-1307, USA.
  18  * Or go to http://www.gnu.org/copyleft/lgpl.html
  19  */
  20
  21 #include "config.h"
  22
  23 #include <math.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <ctype.h>
  27 #include <assert.h>
  28
  29 #include "alMain.h"
  30 #include "AL/al.h"
  31 #include "AL/alc.h"
  32 #include "alSource.h"
  33 #include "alBuffer.h"
  34 #include "alListener.h"
  35 #include "alAuxEffectSlot.h"
  36 #include "alu.h"
  37 #include "bs2b.h"
  38
  39
  40 extern inline void InitiatePositionArrays(ALuint frac, ALuint increment, ALuint *frac_arr, ALuint *pos_arr, ALuint size);
  41
  42
  43 static inline ALfloat Sample_ALbyte(ALbyte val)
  44 { return val * (1.0f/127.0f); }
  45
  46 static inline ALfloat Sample_ALshort(ALshort val)
  47 { return val * (1.0f/32767.0f); }
  48
  49 static inline ALfloat Sample_ALfloat(ALfloat val)
  50 { return val; }
  51
  52 #define DECL_TEMPLATE(T)                                                      \
  53 static void Load_##T(ALfloat *dst, const T *src, ALuint srcstep, ALuint samples)\
  54 {                                                                             \
  55     ALuint i;                                                                 \
  56     for(i = 0;i < samples;i++)                                                \
  57         dst[i] = Sample_##T(src[i*srcstep]);                                  \
  58 }
  59
  60 DECL_TEMPLATE(ALbyte)
  61 DECL_TEMPLATE(ALshort)
  62 DECL_TEMPLATE(ALfloat)
  63
  64 #undef DECL_TEMPLATE
  65
  66 static void LoadData(ALfloat *dst, const ALvoid *src, ALuint srcstep, enum FmtType srctype, ALuint samples)
  67 {
  68     switch(srctype)
  69     {
  70         case FmtByte:
  71             Load_ALbyte(dst, src, srcstep, samples);
  72             break;
  73         case FmtShort:
  74             Load_ALshort(dst, src, srcstep, samples);
  75             break;
  76         case FmtFloat:
  77             Load_ALfloat(dst, src, srcstep, samples);
  78             break;
  79     }
  80 }
  81
  82 static void SilenceData(ALfloat *dst, ALuint samples)
  83 {
  84     ALuint i;
  85     for(i = 0;i < samples;i++)
  86         dst[i] = 0.0f;
  87 }
  88
  89
  90 static const ALfloat *DoFilters(ALfilterState *lpfilter, ALfilterState *hpfilter,
  91                                 ALfloat *restrict dst, const ALfloat *restrict src,
  92                                 ALuint numsamples, enum ActiveFilters type)
  93 {
  94     ALuint i;
  95     switch(type)
  96     {
  97         case AF_None:
  98             break;
  99
 100         case AF_LowPass:
 101             ALfilterState_process(lpfilter, dst, src, numsamples);
 102             return dst;
 103         case AF_HighPass:
 104             ALfilterState_process(hpfilter, dst, src, numsamples);
 105             return dst;
 106
 107         case AF_BandPass:
 108             for(i = 0;i < numsamples;)
 109             {
 110                 ALfloat temp[64];
 111                 ALuint todo = minu(64, numsamples-i);
 112
 113                 ALfilterState_process(lpfilter, temp, src+i, todo);
 114                 ALfilterState_process(hpfilter, dst+i, temp, todo);
 115                 i += todo;
 116             }
 117             return dst;
 118     }
 119     return src;
 120 }
 121
 122
 123 ALvoid MixSource(ALactivesource *src, ALCdevice *Device, ALuint SamplesToDo)
 124 {
 125     ALsource *Source = src->Source;
 126     ALbufferlistitem *BufferListItem;
 127     ALuint DataPosInt, DataPosFrac;
 128     ALboolean Looping;
 129     ALuint increment;
 130     enum Resampler Resampler;
 131     ALenum State;
 132     ALuint OutPos;
 133     ALuint NumChannels;
 134     ALuint SampleSize;
 135     ALint64 DataSize64;
 136     ALuint chan, j;
 137
 138     /* Get source info */
 139     State          = Source->state;
 140     BufferListItem = Source->current_buffer;
 141     DataPosInt     = Source->position;
 142     DataPosFrac    = Source->position_fraction;
 143     Looping        = Source->Looping;
 144     increment      = src->Step;
 145     Resampler      = (increment==FRACTIONONE) ? PointResampler : Source->Resampler;
 146     NumChannels    = Source->NumChannels;
 147     SampleSize     = Source->SampleSize;
 148
 149     /* Get current buffer queue item */
 150
 151     OutPos = 0;
 152     do {
 153         const ALuint BufferPrePadding = ResamplerPrePadding[Resampler];
 154         const ALuint BufferPadding = ResamplerPadding[Resampler];
 155         ALuint SrcBufferSize, DstBufferSize;
 156
 157         /* Figure out how many buffer samples will be needed */
 158         DataSize64  = SamplesToDo-OutPos;
 159         DataSize64 *= increment;
 160         DataSize64 += DataPosFrac+FRACTIONMASK;
 161         DataSize64 >>= FRACTIONBITS;
 162         DataSize64 += BufferPadding+BufferPrePadding;
 163
 164         SrcBufferSize = (ALuint)mini64(DataSize64, BUFFERSIZE);
 165
 166         /* Figure out how many samples we can actually mix from this. */
 167         DataSize64  = SrcBufferSize;
 168         DataSize64 -= BufferPadding+BufferPrePadding;
 169         DataSize64 <<= FRACTIONBITS;
 170         DataSize64 -= DataPosFrac;
 171
 172         DstBufferSize = (ALuint)((DataSize64+(increment-1)) / increment);
 173         DstBufferSize = minu(DstBufferSize, (SamplesToDo-OutPos));
 174
 175         /* Some mixers like having a multiple of 4, so try to give that unless
 176          * this is the last update. */
 177         if(OutPos+DstBufferSize < SamplesToDo)
 178             DstBufferSize &= ~3;
 179
 180         for(chan = 0;chan < NumChannels;chan++)
 181         {
 182             const ALfloat *ResampledData;
 183             ALfloat *SrcData = Device->SourceData;
 184             ALuint SrcDataSize = 0;
 185
 186             if(Source->SourceType == AL_STATIC)
 187             {
 188                 const ALbuffer *ALBuffer = BufferListItem->buffer;
 189                 const ALubyte *Data = ALBuffer->data;
 190                 ALuint DataSize;
 191                 ALuint pos;
 192
 193                 /* If current pos is beyond the loop range, do not loop */
 194                 if(Looping == AL_FALSE || DataPosInt >= (ALuint)ALBuffer->LoopEnd)
 195                 {
 196                     Looping = AL_FALSE;
 197
 198                     if(DataPosInt >= BufferPrePadding)
 199                         pos = DataPosInt - BufferPrePadding;
 200                     else
 201                     {
 202                         DataSize = BufferPrePadding - DataPosInt;
 203                         DataSize = minu(SrcBufferSize - SrcDataSize, DataSize);
 204
 205                         SilenceData(&SrcData[SrcDataSize], DataSize);
 206                         SrcDataSize += DataSize;
 207
 208                         pos = 0;
 209                     }
 210
 211                     /* Copy what's left to play in the source buffer, and clear the
 212                      * rest of the temp buffer */
 213                     DataSize = minu(SrcBufferSize - SrcDataSize, ALBuffer->SampleLen - pos);
 214
 215                     LoadData(&SrcData[SrcDataSize], &Data[(pos*NumChannels + chan)*SampleSize],
 216                              NumChannels, ALBuffer->FmtType, DataSize);
 217                     SrcDataSize += DataSize;
 218
 219                     SilenceData(&SrcData[SrcDataSize], SrcBufferSize - SrcDataSize);
 220                     SrcDataSize += SrcBufferSize - SrcDataSize;
 221                 }
 222                 else
 223                 {
 224                     ALuint LoopStart = ALBuffer->LoopStart;
 225                     ALuint LoopEnd   = ALBuffer->LoopEnd;
 226
 227                     if(DataPosInt >= LoopStart)
 228                     {
 229                         pos = DataPosInt-LoopStart;
 230                         while(pos < BufferPrePadding)
 231                             pos += LoopEnd-LoopStart;
 232                         pos -= BufferPrePadding;
 233                         pos += LoopStart;
 234                     }
 235                     else if(DataPosInt >= BufferPrePadding)
 236                         pos = DataPosInt - BufferPrePadding;
 237                     else
 238                     {
 239                         DataSize = BufferPrePadding - DataPosInt;
 240                         DataSize = minu(SrcBufferSize - SrcDataSize, DataSize);
 241
 242                         SilenceData(&SrcData[SrcDataSize], DataSize);
 243                         SrcDataSize += DataSize;
 244
 245                         pos = 0;
 246                     }
 247
 248                     /* Copy what's left of this loop iteration, then copy repeats
 249                      * of the loop section */
 250                     DataSize = LoopEnd - pos;
 251                     DataSize = minu(SrcBufferSize - SrcDataSize, DataSize);
 252
 253                     LoadData(&SrcData[SrcDataSize], &Data[(pos*NumChannels + chan)*SampleSize],
 254                              NumChannels, ALBuffer->FmtType, DataSize);
 255                     SrcDataSize += DataSize;
 256
 257                     DataSize = LoopEnd-LoopStart;
 258                     while(SrcBufferSize > SrcDataSize)
 259                     {
 260                         DataSize = minu(SrcBufferSize - SrcDataSize, DataSize);
 261
 262                         LoadData(&SrcData[SrcDataSize], &Data[(LoopStart*NumChannels + chan)*SampleSize],
 263                                  NumChannels, ALBuffer->FmtType, DataSize);
 264                         SrcDataSize += DataSize;
 265                     }
 266                 }
 267             }
 268             else
 269             {
 270                 /* Crawl the buffer queue to fill in the temp buffer */
 271                 ALbufferlistitem *tmpiter = BufferListItem;
 272                 ALuint pos;
 273
 274                 if(DataPosInt >= BufferPrePadding)
 275                     pos = DataPosInt - BufferPrePadding;
 276                 else
 277                 {
 278                     pos = BufferPrePadding - DataPosInt;
 279                     while(pos > 0)
 280                     {
 281                         ALbufferlistitem *prev;
 282                         if((prev=tmpiter->prev) != NULL)
 283                             tmpiter = prev;
 284                         else if(Looping)
 285                         {
 286                             while(tmpiter->next)
 287                                 tmpiter = tmpiter->next;
 288                         }
 289                         else
 290                         {
 291                             ALuint DataSize = minu(SrcBufferSize - SrcDataSize, pos);
 292
 293                             SilenceData(&SrcData[SrcDataSize], DataSize);
 294                             SrcDataSize += DataSize;
 295
 296                             pos = 0;
 297                             break;
 298                         }
 299
 300                         if(tmpiter->buffer)
 301                         {
 302                             if((ALuint)tmpiter->buffer->SampleLen > pos)
 303                             {
 304                                 pos = tmpiter->buffer->SampleLen - pos;
 305                                 break;
 306                             }
 307                             pos -= tmpiter->buffer->SampleLen;
 308                         }
 309                     }
 310                 }
 311
 312                 while(tmpiter && SrcBufferSize > SrcDataSize)
 313                 {
 314                     const ALbuffer *ALBuffer;
 315                     if((ALBuffer=tmpiter->buffer) != NULL)
 316                     {
 317                         const ALubyte *Data = ALBuffer->data;
 318                         ALuint DataSize = ALBuffer->SampleLen;
 319
 320                         /* Skip the data already played */
 321                         if(DataSize <= pos)
 322                             pos -= DataSize;
 323                         else
 324                         {
 325                             Data += (pos*NumChannels + chan)*SampleSize;
 326                             DataSize -= pos;
 327                             pos -= pos;
 328
 329                             DataSize = minu(SrcBufferSize - SrcDataSize, DataSize);
 330                             LoadData(&SrcData[SrcDataSize], Data, NumChannels,
 331                                      ALBuffer->FmtType, DataSize);
 332                             SrcDataSize += DataSize;
 333                         }
 334                     }
 335                     tmpiter = tmpiter->next;
 336                     if(!tmpiter && Looping)
 337                         tmpiter = Source->queue;
 338                     else if(!tmpiter)
 339                     {
 340                         SilenceData(&SrcData[SrcDataSize], SrcBufferSize - SrcDataSize);
 341                         SrcDataSize += SrcBufferSize - SrcDataSize;
 342                     }
 343                 }
 344             }
 345
 346             /* Now resample, then filter and mix to the appropriate outputs. */
 347             ResampledData = src->Resample(
 348                 &SrcData[BufferPrePadding], DataPosFrac, increment,
 349                 Device->ResampledData, DstBufferSize
 350             );
 351             {
 352                 DirectParams *parms = &src->Direct;
 353                 const ALfloat *samples;
 354
 355                 samples = DoFilters(
 356                     &parms->Filters[chan].LowPass, &parms->Filters[chan].HighPass,
 357                     Device->FilteredData, ResampledData, DstBufferSize,
 358                     parms->Filters[chan].ActiveType
 359                 );
 360                 if(!src->IsHrtf)
 361                     src->Mix(samples, MaxChannels, parms->OutBuffer, parms->Mix.Gains[chan],
 362                              parms->Counter, OutPos, DstBufferSize);
 363                 else
 364                     src->HrtfMix(
 365                         parms->OutBuffer, samples, parms->Counter, src->Offset,
 366                         OutPos, parms->Mix.Hrtf.IrSize, &parms->Mix.Hrtf.Params[chan],
 367                         &parms->Mix.Hrtf.State[chan], DstBufferSize
 368                     );
 369             }
 370
 371             for(j = 0;j < Device->NumAuxSends;j++)
 372             {
 373                 SendParams *parms = &src->Send[j];
 374                 const ALfloat *samples;
 375
 376                 if(!parms->OutBuffer)
 377                     continue;
 378
 379                 samples = DoFilters(
 380                     &parms->Filters[chan].LowPass, &parms->Filters[chan].HighPass,
 381                     Device->FilteredData, ResampledData, DstBufferSize,
 382                     parms->Filters[chan].ActiveType
 383                 );
 384                 src->Mix(samples, 1, parms->OutBuffer, &parms->Gain,
 385                          parms->Counter, OutPos, DstBufferSize);
 386             }
 387         }
 388         /* Update positions */
 389         DataPosFrac += increment*DstBufferSize;
 390         DataPosInt  += DataPosFrac>>FRACTIONBITS;
 391         DataPosFrac &= FRACTIONMASK;
 392
 393         OutPos += DstBufferSize;
 394         src->Offset += DstBufferSize;
 395         src->Direct.Counter = maxu(src->Direct.Counter, DstBufferSize) - DstBufferSize;
 396         for(j = 0;j < Device->NumAuxSends;j++)
 397             src->Send[j].Counter = maxu(src->Send[j].Counter, DstBufferSize) - DstBufferSize;
 398
 399         /* Handle looping sources */
 400         while(1)
 401         {
 402             const ALbuffer *ALBuffer;
 403             ALuint DataSize = 0;
 404             ALuint LoopStart = 0;
 405             ALuint LoopEnd = 0;
 406
 407             if((ALBuffer=BufferListItem->buffer) != NULL)
 408             {
 409                 DataSize = ALBuffer->SampleLen;
 410                 LoopStart = ALBuffer->LoopStart;
 411                 LoopEnd = ALBuffer->LoopEnd;
 412                 if(LoopEnd > DataPosInt)
 413                     break;
 414             }
 415
 416             if(Looping && Source->SourceType == AL_STATIC)
 417             {
 418                 assert(LoopEnd > LoopStart);
 419                 DataPosInt = ((DataPosInt-LoopStart)%(LoopEnd-LoopStart)) + LoopStart;
 420                 break;
 421             }
 422
 423             if(DataSize > DataPosInt)
 424                 break;
 425
 426             if(BufferListItem->next)
 427                 BufferListItem = BufferListItem->next;
 428             else if(Looping)
 429                 BufferListItem = Source->queue;
 430             else
 431             {
 432                 State = AL_STOPPED;
 433                 BufferListItem = NULL;
 434                 DataPosInt = 0;
 435                 DataPosFrac = 0;
 436                 break;
 437             }
 438
 439             DataPosInt -= DataSize;
 440         }
 441     } while(State == AL_PLAYING && OutPos < SamplesToDo);
 442
 443     /* Update source info */
 444     Source->state             = State;
 445     Source->current_buffer    = BufferListItem;
 446     Source->position          = DataPosInt;
 447     Source->position_fraction = DataPosFrac;
 448 }