Alc/ALu.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 "alThunk.h"
  35 #include "alListener.h"
  36 #include "alAuxEffectSlot.h"
  37 #include "alu.h"
  38 #include "bs2b.h"
  39
  40 #if defined(HAVE_STDINT_H)
  41 #include <stdint.h>
  42 typedef int64_t ALint64;
  43 #elif defined(HAVE___INT64)
  44 typedef __int64 ALint64;
  45 #elif (SIZEOF_LONG == 8)
  46 typedef long ALint64;
  47 #elif (SIZEOF_LONG_LONG == 8)
  48 typedef long long ALint64;
  49 #endif
  50
  51 #define FRACTIONBITS 14
  52 #define FRACTIONMASK ((1L<<FRACTIONBITS)-1)
  53 #define MAX_PITCH 65536
  54
  55 /* Minimum ramp length in milliseconds. The value below was chosen to
  56  * adequately reduce clicks and pops from harsh gain changes. */
  57 #define MIN_RAMP_LENGTH  16
  58
  59 ALboolean DuplicateStereo = AL_FALSE;
  60
  61
  62 static __inline ALfloat aluF2F(ALfloat Value)
  63 {
  64     if(Value < 0.f) return Value/32768.f;
  65     if(Value > 0.f) return Value/32767.f;
  66     return 0.f;
  67 }
  68
  69 static __inline ALshort aluF2S(ALfloat Value)
  70 {
  71     ALint i;
  72
  73     i = (ALint)Value;
  74     i = __min( 32767, i);
  75     i = __max(-32768, i);
  76     return ((ALshort)i);
  77 }
  78
  79 static __inline ALubyte aluF2UB(ALfloat Value)
  80 {
  81     ALshort i = aluF2S(Value);
  82     return (i>>8)+128;
  83 }
  84
  85
  86 static __inline ALvoid aluCrossproduct(const ALfloat *inVector1, const ALfloat *inVector2, ALfloat *outVector)
  87 {
  88     outVector[0] = inVector1[1]*inVector2[2] - inVector1[2]*inVector2[1];
  89     outVector[1] = inVector1[2]*inVector2[0] - inVector1[0]*inVector2[2];
  90     outVector[2] = inVector1[0]*inVector2[1] - inVector1[1]*inVector2[0];
  91 }
  92
  93 static __inline ALfloat aluDotproduct(const ALfloat *inVector1, const ALfloat *inVector2)
  94 {
  95     return inVector1[0]*inVector2[0] + inVector1[1]*inVector2[1] +
  96            inVector1[2]*inVector2[2];
  97 }
  98
  99 static __inline ALvoid aluNormalize(ALfloat *inVector)
 100 {
 101     ALfloat length, inverse_length;
 102
 103     length = aluSqrt(aluDotproduct(inVector, inVector));
 104     if(length != 0.0f)
 105     {
 106         inverse_length = 1.0f/length;
 107         inVector[0] *= inverse_length;
 108         inVector[1] *= inverse_length;
 109         inVector[2] *= inverse_length;
 110     }
 111 }
 112
 113 static __inline ALvoid aluMatrixVector(ALfloat *vector,ALfloat w,ALfloat matrix[4][4])
 114 {
 115     ALfloat temp[4] = {
 116         vector[0], vector[1], vector[2], w
 117     };
 118
 119     vector[0] = temp[0]*matrix[0][0] + temp[1]*matrix[1][0] + temp[2]*matrix[2][0] + temp[3]*matrix[3][0];
 120     vector[1] = temp[0]*matrix[0][1] + temp[1]*matrix[1][1] + temp[2]*matrix[2][1] + temp[3]*matrix[3][1];
 121     vector[2] = temp[0]*matrix[0][2] + temp[1]*matrix[1][2] + temp[2]*matrix[2][2] + temp[3]*matrix[3][2];
 122 }
 123
 124 static ALvoid SetSpeakerArrangement(const char *name, ALfloat SpeakerAngle[OUTPUTCHANNELS],
 125                                     ALint Speaker2Chan[OUTPUTCHANNELS], ALint chans)
 126 {
 127     const char *confkey;
 128     const char *next;
 129     const char *sep;
 130     const char *end;
 131     int i, val;
 132
 133     confkey = GetConfigValue(NULL, name, "");
 134     next = confkey;
 135     while(next && *next)
 136     {
 137         confkey = next;
 138         next = strchr(confkey, ',');
 139         if(next)
 140         {
 141             do {
 142                 next++;
 143             } while(isspace(*next));
 144         }
 145
 146         sep = strchr(confkey, '=');
 147         if(!sep || confkey == sep)
 148             continue;
 149
 150         end = sep - 1;
 151         while(isspace(*end) && end != confkey)
 152             end--;
 153         end++;
 154
 155         if(strncmp(confkey, "fl", end-confkey) == 0)
 156             val = FRONT_LEFT;
 157         else if(strncmp(confkey, "fr", end-confkey) == 0)
 158             val = FRONT_RIGHT;
 159         else if(strncmp(confkey, "fc", end-confkey) == 0)
 160             val = FRONT_CENTER;
 161         else if(strncmp(confkey, "bl", end-confkey) == 0)
 162             val = BACK_LEFT;
 163         else if(strncmp(confkey, "br", end-confkey) == 0)
 164             val = BACK_RIGHT;
 165         else if(strncmp(confkey, "bc", end-confkey) == 0)
 166             val = BACK_CENTER;
 167         else if(strncmp(confkey, "sl", end-confkey) == 0)
 168             val = SIDE_LEFT;
 169         else if(strncmp(confkey, "sr", end-confkey) == 0)
 170             val = SIDE_RIGHT;
 171         else
 172         {
 173             AL_PRINT("Unknown speaker for %s: \"%c%c\"\n", name, confkey[0], confkey[1]);
 174             continue;
 175         }
 176
 177         sep++;
 178         while(isspace(*sep))
 179             sep++;
 180
 181         for(i = 0;i < chans;i++)
 182         {
 183             if(Speaker2Chan[i] == val)
 184             {
 185                 val = strtol(sep, NULL, 10);
 186                 if(val >= -180 && val <= 180)
 187                     SpeakerAngle[i] = val * M_PI/180.0f;
 188                 else
 189                     AL_PRINT("Invalid angle for speaker \"%c%c\": %d\n", confkey[0], confkey[1], val);
 190                 break;
 191             }
 192         }
 193     }
 194
 195     for(i = 1;i < chans;i++)
 196     {
 197         if(SpeakerAngle[i] <= SpeakerAngle[i-1])
 198         {
 199             AL_PRINT("Speaker %d of %d does not follow previous: %f > %f\n", i, chans,
 200                      SpeakerAngle[i-1] * 180.0f/M_PI, SpeakerAngle[i] * 180.0f/M_PI);
 201             SpeakerAngle[i] = SpeakerAngle[i-1] + 1 * 180.0f/M_PI;
 202         }
 203     }
 204 }
 205
 206 static __inline ALfloat aluLUTpos2Angle(ALint pos)
 207 {
 208     if(pos < QUADRANT_NUM)
 209         return aluAtan((ALfloat)pos / (ALfloat)(QUADRANT_NUM - pos));
 210     if(pos < 2 * QUADRANT_NUM)
 211         return M_PI_2 + aluAtan((ALfloat)(pos - QUADRANT_NUM) / (ALfloat)(2 * QUADRANT_NUM - pos));
 212     if(pos < 3 * QUADRANT_NUM)
 213         return aluAtan((ALfloat)(pos - 2 * QUADRANT_NUM) / (ALfloat)(3 * QUADRANT_NUM - pos)) - M_PI;
 214     return aluAtan((ALfloat)(pos - 3 * QUADRANT_NUM) / (ALfloat)(4 * QUADRANT_NUM - pos)) - M_PI_2;
 215 }
 216
 217 ALvoid aluInitPanning(ALCcontext *Context)
 218 {
 219     ALint pos, offset, s;
 220     ALfloat Alpha, Theta;
 221     ALfloat SpeakerAngle[OUTPUTCHANNELS];
 222     ALint Speaker2Chan[OUTPUTCHANNELS];
 223
 224     for(s = 0;s < OUTPUTCHANNELS;s++)
 225     {
 226         int s2;
 227         for(s2 = 0;s2 < OUTPUTCHANNELS;s2++)
 228             Context->ChannelMatrix[s][s2] = ((s==s2) ? 1.0f : 0.0f);
 229     }
 230
 231     switch(Context->Device->Format)
 232     {
 233         /* Mono is rendered as stereo, then downmixed during post-process */
 234         case AL_FORMAT_MONO8:
 235         case AL_FORMAT_MONO16:
 236         case AL_FORMAT_MONO_FLOAT32:
 237             Context->ChannelMatrix[FRONT_CENTER][FRONT_LEFT]  = aluSqrt(0.5);
 238             Context->ChannelMatrix[FRONT_CENTER][FRONT_RIGHT] = aluSqrt(0.5);
 239             Context->ChannelMatrix[SIDE_LEFT][FRONT_LEFT]     = 1.0f;
 240             Context->ChannelMatrix[SIDE_RIGHT][FRONT_RIGHT]   = 1.0f;
 241             Context->ChannelMatrix[BACK_LEFT][FRONT_LEFT]     = 1.0f;
 242             Context->ChannelMatrix[BACK_RIGHT][FRONT_RIGHT]   = 1.0f;
 243             Context->ChannelMatrix[BACK_CENTER][FRONT_LEFT]   = aluSqrt(0.5);
 244             Context->ChannelMatrix[BACK_CENTER][FRONT_RIGHT]  = aluSqrt(0.5);
 245             Context->NumChan = 2;
 246             Speaker2Chan[0] = FRONT_LEFT;
 247             Speaker2Chan[1] = FRONT_RIGHT;
 248             SpeakerAngle[0] = -90.0f * M_PI/180.0f;
 249             SpeakerAngle[1] =  90.0f * M_PI/180.0f;
 250             break;
 251
 252         case AL_FORMAT_STEREO8:
 253         case AL_FORMAT_STEREO16:
 254         case AL_FORMAT_STEREO_FLOAT32:
 255             Context->ChannelMatrix[FRONT_CENTER][FRONT_LEFT]  = aluSqrt(0.5);
 256             Context->ChannelMatrix[FRONT_CENTER][FRONT_RIGHT] = aluSqrt(0.5);
 257             Context->ChannelMatrix[SIDE_LEFT][FRONT_LEFT]     = 1.0f;
 258             Context->ChannelMatrix[SIDE_RIGHT][FRONT_RIGHT]   = 1.0f;
 259             Context->ChannelMatrix[BACK_LEFT][FRONT_LEFT]     = 1.0f;
 260             Context->ChannelMatrix[BACK_RIGHT][FRONT_RIGHT]   = 1.0f;
 261             Context->ChannelMatrix[BACK_CENTER][FRONT_LEFT]   = aluSqrt(0.5);
 262             Context->ChannelMatrix[BACK_CENTER][FRONT_RIGHT]  = aluSqrt(0.5);
 263             Context->NumChan = 2;
 264             Speaker2Chan[0] = FRONT_LEFT;
 265             Speaker2Chan[1] = FRONT_RIGHT;
 266             SpeakerAngle[0] = -90.0f * M_PI/180.0f;
 267             SpeakerAngle[1] =  90.0f * M_PI/180.0f;
 268             SetSpeakerArrangement("layout_STEREO", SpeakerAngle, Speaker2Chan, Context->NumChan);
 269             break;
 270
 271         case AL_FORMAT_QUAD8:
 272         case AL_FORMAT_QUAD16:
 273         case AL_FORMAT_QUAD32:
 274             Context->ChannelMatrix[FRONT_CENTER][FRONT_LEFT]  = aluSqrt(0.5);
 275             Context->ChannelMatrix[FRONT_CENTER][FRONT_RIGHT] = aluSqrt(0.5);
 276             Context->ChannelMatrix[SIDE_LEFT][FRONT_LEFT]     = aluSqrt(0.5);
 277             Context->ChannelMatrix[SIDE_LEFT][BACK_LEFT]      = aluSqrt(0.5);
 278             Context->ChannelMatrix[SIDE_RIGHT][FRONT_RIGHT]   = aluSqrt(0.5);
 279             Context->ChannelMatrix[SIDE_RIGHT][BACK_RIGHT]    = aluSqrt(0.5);
 280             Context->ChannelMatrix[BACK_CENTER][BACK_LEFT]    = aluSqrt(0.5);
 281             Context->ChannelMatrix[BACK_CENTER][BACK_RIGHT]   = aluSqrt(0.5);
 282             Context->NumChan = 4;
 283             Speaker2Chan[0] = BACK_LEFT;
 284             Speaker2Chan[1] = FRONT_LEFT;
 285             Speaker2Chan[2] = FRONT_RIGHT;
 286             Speaker2Chan[3] = BACK_RIGHT;
 287             SpeakerAngle[0] = -135.0f * M_PI/180.0f;
 288             SpeakerAngle[1] =  -45.0f * M_PI/180.0f;
 289             SpeakerAngle[2] =   45.0f * M_PI/180.0f;
 290             SpeakerAngle[3] =  135.0f * M_PI/180.0f;
 291             SetSpeakerArrangement("layout_QUAD", SpeakerAngle, Speaker2Chan, Context->NumChan);
 292             break;
 293
 294         case AL_FORMAT_51CHN8:
 295         case AL_FORMAT_51CHN16:
 296         case AL_FORMAT_51CHN32:
 297             Context->ChannelMatrix[SIDE_LEFT][FRONT_LEFT]   = aluSqrt(0.5);
 298             Context->ChannelMatrix[SIDE_LEFT][BACK_LEFT]    = aluSqrt(0.5);
 299             Context->ChannelMatrix[SIDE_RIGHT][FRONT_RIGHT] = aluSqrt(0.5);
 300             Context->ChannelMatrix[SIDE_RIGHT][BACK_RIGHT]  = aluSqrt(0.5);
 301             Context->ChannelMatrix[BACK_CENTER][BACK_LEFT]  = aluSqrt(0.5);
 302             Context->ChannelMatrix[BACK_CENTER][BACK_RIGHT] = aluSqrt(0.5);
 303             Context->NumChan = 5;
 304             Speaker2Chan[0] = BACK_LEFT;
 305             Speaker2Chan[1] = FRONT_LEFT;
 306             Speaker2Chan[2] = FRONT_CENTER;
 307             Speaker2Chan[3] = FRONT_RIGHT;
 308             Speaker2Chan[4] = BACK_RIGHT;
 309             SpeakerAngle[0] = -110.0f * M_PI/180.0f;
 310             SpeakerAngle[1] =  -30.0f * M_PI/180.0f;
 311             SpeakerAngle[2] =    0.0f * M_PI/180.0f;
 312             SpeakerAngle[3] =   30.0f * M_PI/180.0f;
 313             SpeakerAngle[4] =  110.0f * M_PI/180.0f;
 314             SetSpeakerArrangement("layout_51CHN", SpeakerAngle, Speaker2Chan, Context->NumChan);
 315             break;
 316
 317         case AL_FORMAT_61CHN8:
 318         case AL_FORMAT_61CHN16:
 319         case AL_FORMAT_61CHN32:
 320             Context->ChannelMatrix[BACK_LEFT][BACK_CENTER]  = aluSqrt(0.5);
 321             Context->ChannelMatrix[BACK_LEFT][SIDE_LEFT]    = aluSqrt(0.5);
 322             Context->ChannelMatrix[BACK_RIGHT][BACK_CENTER] = aluSqrt(0.5);
 323             Context->ChannelMatrix[BACK_RIGHT][SIDE_RIGHT]  = aluSqrt(0.5);
 324             Context->NumChan = 6;
 325             Speaker2Chan[0] = SIDE_LEFT;
 326             Speaker2Chan[1] = FRONT_LEFT;
 327             Speaker2Chan[2] = FRONT_CENTER;
 328             Speaker2Chan[3] = FRONT_RIGHT;
 329             Speaker2Chan[4] = SIDE_RIGHT;
 330             Speaker2Chan[5] = BACK_CENTER;
 331             SpeakerAngle[0] = -90.0f * M_PI/180.0f;
 332             SpeakerAngle[1] = -30.0f * M_PI/180.0f;
 333             SpeakerAngle[2] =   0.0f * M_PI/180.0f;
 334             SpeakerAngle[3] =  30.0f * M_PI/180.0f;
 335             SpeakerAngle[4] =  90.0f * M_PI/180.0f;
 336             SpeakerAngle[5] = 180.0f * M_PI/180.0f;
 337             SetSpeakerArrangement("layout_61CHN", SpeakerAngle, Speaker2Chan, Context->NumChan);
 338             break;
 339
 340         case AL_FORMAT_71CHN8:
 341         case AL_FORMAT_71CHN16:
 342         case AL_FORMAT_71CHN32:
 343             Context->ChannelMatrix[BACK_CENTER][BACK_LEFT]  = aluSqrt(0.5);
 344             Context->ChannelMatrix[BACK_CENTER][BACK_RIGHT] = aluSqrt(0.5);
 345             Context->NumChan = 7;
 346             Speaker2Chan[0] = BACK_LEFT;
 347             Speaker2Chan[1] = SIDE_LEFT;
 348             Speaker2Chan[2] = FRONT_LEFT;
 349             Speaker2Chan[3] = FRONT_CENTER;
 350             Speaker2Chan[4] = FRONT_RIGHT;
 351             Speaker2Chan[5] = SIDE_RIGHT;
 352             Speaker2Chan[6] = BACK_RIGHT;
 353             SpeakerAngle[0] = -150.0f * M_PI/180.0f;
 354             SpeakerAngle[1] =  -90.0f * M_PI/180.0f;
 355             SpeakerAngle[2] =  -30.0f * M_PI/180.0f;
 356             SpeakerAngle[3] =    0.0f * M_PI/180.0f;
 357             SpeakerAngle[4] =   30.0f * M_PI/180.0f;
 358             SpeakerAngle[5] =   90.0f * M_PI/180.0f;
 359             SpeakerAngle[6] =  150.0f * M_PI/180.0f;
 360             SetSpeakerArrangement("layout_71CHN", SpeakerAngle, Speaker2Chan, Context->NumChan);
 361             break;
 362
 363         default:
 364             assert(0);
 365     }
 366
 367     for(pos = 0; pos < LUT_NUM; pos++)
 368     {
 369         /* source angle */
 370         Theta = aluLUTpos2Angle(pos);
 371
 372         /* clear all values */
 373         offset = OUTPUTCHANNELS * pos;
 374         for(s = 0; s < OUTPUTCHANNELS; s++)
 375             Context->PanningLUT[offset+s] = 0.0f;
 376
 377         /* set panning values */
 378         for(s = 0; s < Context->NumChan - 1; s++)
 379         {
 380             if(Theta >= SpeakerAngle[s] && Theta < SpeakerAngle[s+1])
 381             {
 382                 /* source between speaker s and speaker s+1 */
 383                 Alpha = M_PI_2 * (Theta-SpeakerAngle[s]) /
 384                                  (SpeakerAngle[s+1]-SpeakerAngle[s]);
 385                 Context->PanningLUT[offset + Speaker2Chan[s]]   = cos(Alpha);
 386                 Context->PanningLUT[offset + Speaker2Chan[s+1]] = sin(Alpha);
 387                 break;
 388             }
 389         }
 390         if(s == Context->NumChan - 1)
 391         {
 392             /* source between last and first speaker */
 393             if(Theta < SpeakerAngle[0])
 394                 Theta += 2.0f * M_PI;
 395             Alpha = M_PI_2 * (Theta-SpeakerAngle[s]) /
 396                              (2.0f * M_PI + SpeakerAngle[0]-SpeakerAngle[s]);
 397             Context->PanningLUT[offset + Speaker2Chan[s]] = cos(Alpha);
 398             Context->PanningLUT[offset + Speaker2Chan[0]] = sin(Alpha);
 399         }
 400     }
 401 }
 402
 403 static ALvoid CalcSourceParams(const ALCcontext *ALContext, ALsource *ALSource,
 404                                ALboolean isMono)
 405 {
 406     ALfloat InnerAngle,OuterAngle,Angle,Distance,DryMix;
 407     ALfloat Direction[3],Position[3],SourceToListener[3];
 408     ALfloat Velocity[3],ListenerVel[3];
 409     ALfloat MinVolume,MaxVolume,MinDist,MaxDist,Rolloff,OuterGainHF;
 410     ALfloat ConeVolume,ConeHF,SourceVolume,ListenerGain;
 411     ALfloat DopplerFactor, DopplerVelocity, flSpeedOfSound;
 412     ALfloat Matrix[4][4];
 413     ALfloat flAttenuation;
 414     ALfloat RoomAttenuation[MAX_SENDS];
 415     ALfloat MetersPerUnit;
 416     ALfloat RoomRolloff[MAX_SENDS];
 417     ALfloat DryGainHF = 1.0f;
 418     ALfloat WetGain[MAX_SENDS];
 419     ALfloat WetGainHF[MAX_SENDS];
 420     ALfloat DirGain, AmbientGain;
 421     ALfloat length;
 422     const ALfloat *SpeakerGain;
 423     ALuint Frequency;
 424     ALint NumSends;
 425     ALint pos, s, i;
 426     ALfloat cw, a, g;
 427
 428     //Get context properties
 429     DopplerFactor   = ALContext->DopplerFactor * ALSource->DopplerFactor;
 430     DopplerVelocity = ALContext->DopplerVelocity;
 431     flSpeedOfSound  = ALContext->flSpeedOfSound;
 432     NumSends        = ALContext->Device->NumAuxSends;
 433     Frequency       = ALContext->Device->Frequency;
 434
 435     //Get listener properties
 436     ListenerGain = ALContext->Listener.Gain;
 437     MetersPerUnit = ALContext->Listener.MetersPerUnit;
 438     memcpy(ListenerVel, ALContext->Listener.Velocity, sizeof(ALContext->Listener.Velocity));
 439
 440     //Get source properties
 441     SourceVolume = ALSource->flGain;
 442     memcpy(Position,  ALSource->vPosition,    sizeof(ALSource->vPosition));
 443     memcpy(Direction, ALSource->vOrientation, sizeof(ALSource->vOrientation));
 444     memcpy(Velocity,  ALSource->vVelocity,    sizeof(ALSource->vVelocity));
 445     MinVolume    = ALSource->flMinGain;
 446     MaxVolume    = ALSource->flMaxGain;
 447     MinDist      = ALSource->flRefDistance;
 448     MaxDist      = ALSource->flMaxDistance;
 449     Rolloff      = ALSource->flRollOffFactor;
 450     InnerAngle   = ALSource->flInnerAngle;
 451     OuterAngle   = ALSource->flOuterAngle;
 452     OuterGainHF  = ALSource->OuterGainHF;
 453
 454     //Only apply 3D calculations for mono buffers
 455     if(isMono == AL_FALSE)
 456     {
 457         //1. Multi-channel buffers always play "normal"
 458         ALSource->Params.Pitch = ALSource->flPitch;
 459
 460         DryMix = SourceVolume;
 461         DryMix = __min(DryMix,MaxVolume);
 462         DryMix = __max(DryMix,MinVolume);
 463
 464         switch(ALSource->DirectFilter.type)
 465         {
 466             case AL_FILTER_LOWPASS:
 467                 DryMix *= ALSource->DirectFilter.Gain;
 468                 DryGainHF *= ALSource->DirectFilter.GainHF;
 469                 break;
 470         }
 471
 472         ALSource->Params.DryGains[FRONT_LEFT]   = DryMix * ListenerGain;
 473         ALSource->Params.DryGains[FRONT_RIGHT]  = DryMix * ListenerGain;
 474         ALSource->Params.DryGains[SIDE_LEFT]    = DryMix * ListenerGain;
 475         ALSource->Params.DryGains[SIDE_RIGHT]   = DryMix * ListenerGain;
 476         ALSource->Params.DryGains[BACK_LEFT]    = DryMix * ListenerGain;
 477         ALSource->Params.DryGains[BACK_RIGHT]   = DryMix * ListenerGain;
 478         ALSource->Params.DryGains[FRONT_CENTER] = DryMix * ListenerGain;
 479         ALSource->Params.DryGains[BACK_CENTER]  = DryMix * ListenerGain;
 480         ALSource->Params.DryGains[LFE]          = DryMix * ListenerGain;
 481         for(i = 0;i < MAX_SENDS;i++)
 482             ALSource->Params.WetGains[i] = 0.0f;
 483
 484         /* Update filter coefficients. Calculations based on the I3DL2
 485          * spec. */
 486         cw = cos(2.0*M_PI * LOWPASSFREQCUTOFF / Frequency);
 487         /* We use two chained one-pole filters, so we need to take the
 488          * square root of the squared gain, which is the same as the base
 489          * gain. */
 490         g = __max(DryGainHF, 0.01f);
 491         a = 0.0f;
 492         /* Be careful with gains < 0.0001, as that causes the coefficient
 493          * head towards 1, which will flatten the signal */
 494         if(g < 0.9999f) /* 1-epsilon */
 495             a = (1 - g*cw - aluSqrt(2*g*(1-cw) - g*g*(1 - cw*cw))) /
 496                 (1 - g);
 497         ALSource->Params.iirFilter.coeff = a;
 498         for(i = 0;i < MAX_SENDS;i++)
 499             ALSource->Params.Send[i].iirFilter.coeff = 0.0f;
 500
 501         return;
 502     }
 503
 504     //1. Translate Listener to origin (convert to head relative)
 505     if(ALSource->bHeadRelative==AL_FALSE)
 506     {
 507         ALfloat U[3],V[3],N[3],P[3];
 508
 509         // Build transform matrix
 510         memcpy(N, ALContext->Listener.Forward, sizeof(N));  // At-vector
 511         aluNormalize(N);  // Normalized At-vector
 512         memcpy(V, ALContext->Listener.Up, sizeof(V));  // Up-vector
 513         aluNormalize(V);  // Normalized Up-vector
 514         aluCrossproduct(N, V, U); // Right-vector
 515         aluNormalize(U);  // Normalized Right-vector
 516         P[0] = -(ALContext->Listener.Position[0]*U[0] + // Translation
 517                  ALContext->Listener.Position[1]*U[1] +
 518                  ALContext->Listener.Position[2]*U[2]);
 519         P[1] = -(ALContext->Listener.Position[0]*V[0] +
 520                  ALContext->Listener.Position[1]*V[1] +
 521                  ALContext->Listener.Position[2]*V[2]);
 522         P[2] = -(ALContext->Listener.Position[0]*-N[0] +
 523                  ALContext->Listener.Position[1]*-N[1] +
 524                  ALContext->Listener.Position[2]*-N[2]);
 525         Matrix[0][0] = U[0]; Matrix[0][1] = V[0]; Matrix[0][2] = -N[0]; Matrix[0][3] = 0.0f;
 526         Matrix[1][0] = U[1]; Matrix[1][1] = V[1]; Matrix[1][2] = -N[1]; Matrix[1][3] = 0.0f;
 527         Matrix[2][0] = U[2]; Matrix[2][1] = V[2]; Matrix[2][2] = -N[2]; Matrix[2][3] = 0.0f;
 528         Matrix[3][0] = P[0]; Matrix[3][1] = P[1]; Matrix[3][2] =  P[2]; Matrix[3][3] = 1.0f;
 529
 530         // Transform source position and direction into listener space
 531         aluMatrixVector(Position, 1.0f, Matrix);
 532         aluMatrixVector(Direction, 0.0f, Matrix);
 533         // Transform source and listener velocity into listener space
 534         aluMatrixVector(Velocity, 0.0f, Matrix);
 535         aluMatrixVector(ListenerVel, 0.0f, Matrix);
 536     }
 537     else
 538         ListenerVel[0] = ListenerVel[1] = ListenerVel[2] = 0.0f;
 539
 540     SourceToListener[0] = -Position[0];
 541     SourceToListener[1] = -Position[1];
 542     SourceToListener[2] = -Position[2];
 543     aluNormalize(SourceToListener);
 544     aluNormalize(Direction);
 545
 546     //2. Calculate distance attenuation
 547     Distance = aluSqrt(aluDotproduct(Position, Position));
 548
 549     flAttenuation = 1.0f;
 550     for(i = 0;i < MAX_SENDS;i++)
 551     {
 552         RoomAttenuation[i] = 1.0f;
 553
 554         RoomRolloff[i] = ALSource->RoomRolloffFactor;
 555         if(ALSource->Send[i].Slot &&
 556            (ALSource->Send[i].Slot->effect.type == AL_EFFECT_REVERB ||
 557             ALSource->Send[i].Slot->effect.type == AL_EFFECT_EAXREVERB))
 558             RoomRolloff[i] += ALSource->Send[i].Slot->effect.Reverb.RoomRolloffFactor;
 559     }
 560
 561     switch(ALSource->DistanceModel)
 562     {
 563         case AL_INVERSE_DISTANCE_CLAMPED:
 564             Distance=__max(Distance,MinDist);
 565             Distance=__min(Distance,MaxDist);
 566             if(MaxDist < MinDist)
 567                 break;
 568             //fall-through
 569         case AL_INVERSE_DISTANCE:
 570             if(MinDist > 0.0f)
 571             {
 572                 if((MinDist + (Rolloff * (Distance - MinDist))) > 0.0f)
 573                     flAttenuation = MinDist / (MinDist + (Rolloff * (Distance - MinDist)));
 574                 for(i = 0;i < NumSends;i++)
 575                 {
 576                     if((MinDist + (RoomRolloff[i] * (Distance - MinDist))) > 0.0f)
 577                         RoomAttenuation[i] = MinDist / (MinDist + (RoomRolloff[i] * (Distance - MinDist)));
 578                 }
 579             }
 580             break;
 581
 582         case AL_LINEAR_DISTANCE_CLAMPED:
 583             Distance=__max(Distance,MinDist);
 584             Distance=__min(Distance,MaxDist);
 585             if(MaxDist < MinDist)
 586                 break;
 587             //fall-through
 588         case AL_LINEAR_DISTANCE:
 589             Distance=__min(Distance,MaxDist);
 590             if(MaxDist != MinDist)
 591             {
 592                 flAttenuation = 1.0f - (Rolloff*(Distance-MinDist)/(MaxDist - MinDist));
 593                 for(i = 0;i < NumSends;i++)
 594                     RoomAttenuation[i] = 1.0f - (RoomRolloff[i]*(Distance-MinDist)/(MaxDist - MinDist));
 595             }
 596             break;
 597
 598         case AL_EXPONENT_DISTANCE_CLAMPED:
 599             Distance=__max(Distance,MinDist);
 600             Distance=__min(Distance,MaxDist);
 601             if(MaxDist < MinDist)
 602                 break;
 603             //fall-through
 604         case AL_EXPONENT_DISTANCE:
 605             if(Distance > 0.0f && MinDist > 0.0f)
 606             {
 607                 flAttenuation = (ALfloat)pow(Distance/MinDist, -Rolloff);
 608                 for(i = 0;i < NumSends;i++)
 609                     RoomAttenuation[i] = (ALfloat)pow(Distance/MinDist, -RoomRolloff[i]);
 610             }
 611             break;
 612
 613         case AL_NONE:
 614             break;
 615     }
 616
 617     // Source Gain + Attenuation and clamp to Min/Max Gain
 618     DryMix = SourceVolume * flAttenuation;
 619     DryMix = __min(DryMix,MaxVolume);
 620     DryMix = __max(DryMix,MinVolume);
 621
 622     for(i = 0;i < NumSends;i++)
 623     {
 624         ALfloat WetMix = SourceVolume * RoomAttenuation[i];
 625         WetMix = __min(WetMix,MaxVolume);
 626         WetGain[i] = __max(WetMix,MinVolume);
 627         WetGainHF[i] = 1.0f;
 628     }
 629
 630     // Distance-based air absorption
 631     if(ALSource->AirAbsorptionFactor > 0.0f && flAttenuation < 1.0f)
 632     {
 633         ALfloat absorb = 0.0f;
 634
 635         // Absorption calculation is done in dB
 636         if(flAttenuation > 0.0f)
 637         {
 638             absorb = (MinDist/flAttenuation - MinDist)*MetersPerUnit *
 639                      (ALSource->AirAbsorptionFactor*AIRABSORBGAINDBHF);
 640             // Convert dB to linear gain before applying
 641             absorb = pow(10.0, absorb/20.0);
 642         }
 643         DryGainHF *= absorb;
 644         for(i = 0;i < MAX_SENDS;i++)
 645             WetGainHF[i] *= absorb;
 646     }
 647
 648     //3. Apply directional soundcones
 649     Angle = aluAcos(aluDotproduct(Direction,SourceToListener)) * 180.0f/M_PI;
 650     if(Angle >= InnerAngle && Angle <= OuterAngle)
 651     {
 652         ALfloat scale = (Angle-InnerAngle) / (OuterAngle-InnerAngle);
 653         ConeVolume = (1.0f+(ALSource->flOuterGain-1.0f)*scale);
 654         ConeHF = (1.0f+(OuterGainHF-1.0f)*scale);
 655         DryMix *= ConeVolume;
 656         if(ALSource->DryGainHFAuto)
 657             DryGainHF *= ConeHF;
 658     }
 659     else if(Angle > OuterAngle)
 660     {
 661         ConeVolume = (1.0f+(ALSource->flOuterGain-1.0f));
 662         ConeHF = (1.0f+(OuterGainHF-1.0f));
 663         DryMix *= ConeVolume;
 664         if(ALSource->DryGainHFAuto)
 665             DryGainHF *= ConeHF;
 666     }
 667     else
 668     {
 669         ConeVolume = 1.0f;
 670         ConeHF = 1.0f;
 671     }
 672
 673     //4. Calculate Velocity
 674     if(DopplerFactor != 0.0f)
 675     {
 676         ALfloat flVSS, flVLS;
 677         ALfloat flMaxVelocity = (DopplerVelocity * flSpeedOfSound) /
 678                                 DopplerFactor;
 679
 680         flVSS = aluDotproduct(Velocity, SourceToListener);
 681         if(flVSS >= flMaxVelocity)
 682             flVSS = (flMaxVelocity - 1.0f);
 683         else if(flVSS <= -flMaxVelocity)
 684             flVSS = -flMaxVelocity + 1.0f;
 685
 686         flVLS = aluDotproduct(ListenerVel, SourceToListener);
 687         if(flVLS >= flMaxVelocity)
 688             flVLS = (flMaxVelocity - 1.0f);
 689         else if(flVLS <= -flMaxVelocity)
 690             flVLS = -flMaxVelocity + 1.0f;
 691
 692         ALSource->Params.Pitch = ALSource->flPitch *
 693             ((flSpeedOfSound * DopplerVelocity) - (DopplerFactor * flVLS)) /
 694             ((flSpeedOfSound * DopplerVelocity) - (DopplerFactor * flVSS));
 695     }
 696     else
 697         ALSource->Params.Pitch = ALSource->flPitch;
 698
 699     for(i = 0;i < NumSends;i++)
 700     {
 701         if(ALSource->Send[i].Slot &&
 702            ALSource->Send[i].Slot->effect.type != AL_EFFECT_NULL)
 703         {
 704             if(ALSource->Send[i].Slot->AuxSendAuto)
 705             {
 706                 if(ALSource->WetGainAuto)
 707                     WetGain[i] *= ConeVolume;
 708                 if(ALSource->WetGainHFAuto)
 709                     WetGainHF[i] *= ConeHF;
 710
 711                 if(ALSource->Send[i].Slot->effect.type == AL_EFFECT_REVERB ||
 712                    ALSource->Send[i].Slot->effect.type == AL_EFFECT_EAXREVERB)
 713                 {
 714                     /* Apply a decay-time transformation to the wet path,
 715                      * based on the attenuation of the dry path.  This should
 716                      * better approximate the statistical attenuation model
 717                      * for the reverb effect.
 718                      *
 719                      * This simple equation converts the distance attenuation
 720                      * into the time it would take to reach -60 dB. From
 721                      * there it establishes an origin (0.333s; the decay time
 722                      * that will produce equal attenuation) and applies the
 723                      * current decay time.  Finally, it converts the result
 724                      * back to an attenuation for the reverb path.
 725                      */
 726                     WetGain[i] *= pow(10.0f, log10(flAttenuation) * 0.333f /
 727                         ALSource->Send[i].Slot->effect.Reverb.DecayTime);
 728                 }
 729             }
 730             else
 731             {
 732                 // If the slot's auxiliary send auto is off, the data sent to
 733                 // the effect slot is the same as the dry path, sans filter
 734                 // effects
 735                 WetGain[i] = DryMix;
 736                 WetGainHF[i] = DryGainHF;
 737             }
 738
 739             switch(ALSource->Send[i].WetFilter.type)
 740             {
 741                 case AL_FILTER_LOWPASS:
 742                     WetGain[i] *= ALSource->Send[i].WetFilter.Gain;
 743                     WetGainHF[i] *= ALSource->Send[i].WetFilter.GainHF;
 744                     break;
 745             }
 746             ALSource->Params.WetGains[i] = WetGain[i] * ListenerGain;
 747         }
 748         else
 749         {
 750             ALSource->Params.WetGains[i] = 0.0f;
 751             WetGainHF[i] = 1.0f;
 752         }
 753     }
 754     for(i = NumSends;i < MAX_SENDS;i++)
 755     {
 756         ALSource->Params.WetGains[i] = 0.0f;
 757         WetGainHF[i] = 1.0f;
 758     }
 759
 760     //5. Apply filter gains and filters
 761     switch(ALSource->DirectFilter.type)
 762     {
 763         case AL_FILTER_LOWPASS:
 764             DryMix *= ALSource->DirectFilter.Gain;
 765             DryGainHF *= ALSource->DirectFilter.GainHF;
 766             break;
 767     }
 768     DryMix *= ListenerGain;
 769
 770     // Use energy-preserving panning algorithm for multi-speaker playback
 771     length = aluSqrt(Position[0]*Position[0] + Position[1]*Position[1] +
 772                      Position[2]*Position[2]);
 773     length = __max(length, MinDist);
 774     if(length > 0.0f)
 775     {
 776         ALfloat invlen = 1.0f/length;
 777         Position[0] *= invlen;
 778         Position[1] *= invlen;
 779         Position[2] *= invlen;
 780     }
 781
 782     pos = aluCart2LUTpos(-Position[2], Position[0]);
 783     SpeakerGain = &ALContext->PanningLUT[OUTPUTCHANNELS * pos];
 784
 785     DirGain = aluSqrt(Position[0]*Position[0] + Position[2]*Position[2]);
 786     // elevation adjustment for directional gain. this sucks, but
 787     // has low complexity
 788     AmbientGain = 1.0/aluSqrt(ALContext->NumChan) * (1.0-DirGain);
 789     for(s = 0; s < OUTPUTCHANNELS; s++)
 790     {
 791         ALfloat gain = SpeakerGain[s]*DirGain + AmbientGain;
 792         ALSource->Params.DryGains[s] = DryMix * gain;
 793     }
 794
 795     /* Update filter coefficients. */
 796     cw = cos(2.0*M_PI * LOWPASSFREQCUTOFF / Frequency);
 797     /* Spatialized sources use four chained one-pole filters, so we need to
 798      * take the fourth root of the squared gain, which is the same as the
 799      * square root of the base gain. */
 800     g = aluSqrt(__max(DryGainHF, 0.0001f));
 801     a = 0.0f;
 802     if(g < 0.9999f) /* 1-epsilon */
 803         a = (1 - g*cw - aluSqrt(2*g*(1-cw) - g*g*(1 - cw*cw))) /
 804             (1 - g);
 805     ALSource->Params.iirFilter.coeff = a;
 806
 807     for(i = 0;i < NumSends;i++)
 808     {
 809         /* The wet path uses two chained one-pole filters, so take the
 810          * base gain (square root of the squared gain) */
 811         g = __max(WetGainHF[i], 0.01f);
 812         a = 0.0f;
 813         if(g < 0.9999f) /* 1-epsilon */
 814             a = (1 - g*cw - aluSqrt(2*g*(1-cw) - g*g*(1 - cw*cw))) /
 815                 (1 - g);
 816         ALSource->Params.Send[i].iirFilter.coeff = a;
 817     }
 818 }
 819
 820 static __inline ALshort lerp(ALshort val1, ALshort val2, ALint frac)
 821 {
 822     return val1 + (((val2-val1)*frac)>>FRACTIONBITS);
 823 }
 824
 825 static void MixSomeSources(ALCcontext *ALContext, float (*DryBuffer)[OUTPUTCHANNELS], ALuint SamplesToDo)
 826 {
 827     static float DummyBuffer[BUFFERSIZE];
 828     ALfloat *WetBuffer[MAX_SENDS];
 829     ALfloat (*Matrix)[OUTPUTCHANNELS] = ALContext->ChannelMatrix;
 830     ALfloat DrySend[OUTPUTCHANNELS];
 831     ALfloat dryGainStep[OUTPUTCHANNELS];
 832     ALfloat wetGainStep[MAX_SENDS];
 833     ALuint i, j, k, out;
 834     ALsource *ALSource;
 835     ALfloat value;
 836     ALbufferlistitem *BufferListItem;
 837     ALint64 DataSize64,DataPos64;
 838     FILTER *DryFilter, *WetFilter[MAX_SENDS];
 839     ALfloat WetSend[MAX_SENDS];
 840     ALuint rampLength;
 841     ALuint DeviceFreq;
 842     ALint increment;
 843     ALuint DataPosInt, DataPosFrac;
 844     ALuint Channels, Bytes;
 845     ALuint Frequency;
 846     ALuint BuffersPlayed;
 847     ALfloat Pitch;
 848     ALenum State;
 849
 850     if(!(ALSource=ALContext->Source))
 851         return;
 852
 853     DeviceFreq = ALContext->Device->Frequency;
 854
 855     rampLength = DeviceFreq * MIN_RAMP_LENGTH / 1000;
 856     rampLength = max(rampLength, SamplesToDo);
 857
 858 another_source:
 859     State = ALSource->state;
 860     if(State != AL_PLAYING)
 861     {
 862         if((ALSource=ALSource->next) != NULL)
 863             goto another_source;
 864         return;
 865     }
 866     j = 0;
 867
 868     /* Find buffer format */
 869     Frequency = 0;
 870     Channels = 0;
 871     Bytes = 0;
 872     BufferListItem = ALSource->queue;
 873     while(BufferListItem != NULL)
 874     {
 875         ALbuffer *ALBuffer;
 876         if((ALBuffer=BufferListItem->buffer) != NULL)
 877         {
 878             Channels  = aluChannelsFromFormat(ALBuffer->format);
 879             Bytes     = aluBytesFromFormat(ALBuffer->format);
 880             Frequency = ALBuffer->frequency;
 881             break;
 882         }
 883         BufferListItem = BufferListItem->next;
 884     }
 885
 886     /* Get source info */
 887     BuffersPlayed = ALSource->BuffersPlayed;
 888     DataPosInt    = ALSource->position;
 889     DataPosFrac   = ALSource->position_fraction;
 890
 891     CalcSourceParams(ALContext, ALSource, (Channels==1)?AL_TRUE:AL_FALSE);
 892
 893     /* Compute 18.14 fixed point step */
 894     Pitch = (ALSource->Params.Pitch*Frequency) / DeviceFreq;
 895     if(Pitch > (float)MAX_PITCH)  Pitch = (float)MAX_PITCH;
 896     increment = (ALint)(Pitch*(ALfloat)(1L<<FRACTIONBITS));
 897     if(increment <= 0)  increment = (1<<FRACTIONBITS);
 898
 899     /* Compute the gain steps for each output channel */
 900     if(ALSource->FirstStart)
 901     {
 902         for(i = 0;i < OUTPUTCHANNELS;i++)
 903             DrySend[i] = ALSource->Params.DryGains[i];
 904         for(i = 0;i < MAX_SENDS;i++)
 905             WetSend[i] = ALSource->Params.WetGains[i];
 906     }
 907     else
 908     {
 909         for(i = 0;i < OUTPUTCHANNELS;i++)
 910             DrySend[i] = ALSource->DryGains[i];
 911         for(i = 0;i < MAX_SENDS;i++)
 912             WetSend[i] = ALSource->WetGains[i];
 913     }
 914
 915     DryFilter = &ALSource->Params.iirFilter;
 916     for(i = 0;i < MAX_SENDS;i++)
 917     {
 918         WetFilter[i] = &ALSource->Params.Send[i].iirFilter;
 919         WetBuffer[i] = (ALSource->Send[i].Slot ?
 920                         ALSource->Send[i].Slot->WetBuffer :
 921                         DummyBuffer);
 922     }
 923
 924     if(DuplicateStereo && Channels == 2)
 925     {
 926         Matrix[FRONT_LEFT][SIDE_LEFT]   = 1.0f;
 927         Matrix[FRONT_RIGHT][SIDE_RIGHT] = 1.0f;
 928         Matrix[FRONT_LEFT][BACK_LEFT]   = 1.0f;
 929         Matrix[FRONT_RIGHT][BACK_RIGHT] = 1.0f;
 930     }
 931     else if(DuplicateStereo)
 932     {
 933         Matrix[FRONT_LEFT][SIDE_LEFT]   = 0.0f;
 934         Matrix[FRONT_RIGHT][SIDE_RIGHT] = 0.0f;
 935         Matrix[FRONT_LEFT][BACK_LEFT]   = 0.0f;
 936         Matrix[FRONT_RIGHT][BACK_RIGHT] = 0.0f;
 937     }
 938
 939     /* Get current buffer queue item */
 940     BufferListItem = ALSource->queue;
 941     for(i = 0;i < BuffersPlayed && BufferListItem;i++)
 942         BufferListItem = BufferListItem->next;
 943
 944     while(State == AL_PLAYING && j < SamplesToDo)
 945     {
 946         ALuint DataSize = 0;
 947         ALbuffer *ALBuffer;
 948         ALshort *Data;
 949         ALuint BufferSize;
 950
 951         /* Get buffer info */
 952         if((ALBuffer=BufferListItem->buffer) != NULL)
 953         {
 954             Data      = ALBuffer->data;
 955             DataSize  = ALBuffer->size;
 956             DataSize /= Channels * Bytes;
 957         }
 958         if(DataPosInt >= DataSize)
 959             goto skipmix;
 960
 961         if(BufferListItem->next)
 962         {
 963             ALbuffer *NextBuf = BufferListItem->next->buffer;
 964             if(NextBuf && NextBuf->data)
 965             {
 966                 ALint ulExtraSamples = BUFFER_PADDING*Channels*Bytes;
 967                 ulExtraSamples = min(NextBuf->size, ulExtraSamples);
 968                 memcpy(&Data[DataSize*Channels], NextBuf->data, ulExtraSamples);
 969             }
 970         }
 971         else if(ALSource->bLooping)
 972         {
 973             ALbuffer *NextBuf = ALSource->queue->buffer;
 974             if(NextBuf && NextBuf->data)
 975             {
 976                 ALint ulExtraSamples = BUFFER_PADDING*Channels*Bytes;
 977                 ulExtraSamples = min(NextBuf->size, ulExtraSamples);
 978                 memcpy(&Data[DataSize*Channels], NextBuf->data, ulExtraSamples);
 979             }
 980         }
 981         else
 982             memset(&Data[DataSize*Channels], 0, (BUFFER_PADDING*Channels*Bytes));
 983
 984         /* Compute the gain steps for each output channel */
 985         for(i = 0;i < OUTPUTCHANNELS;i++)
 986             dryGainStep[i] = (ALSource->Params.DryGains[i]-
 987                               DrySend[i]) / rampLength;
 988         for(i = 0;i < MAX_SENDS;i++)
 989             wetGainStep[i] = (ALSource->Params.WetGains[i]-
 990                               WetSend[i]) / rampLength;
 991
 992         /* Figure out how many samples we can mix. */
 993         DataSize64 = DataSize;
 994         DataSize64 <<= FRACTIONBITS;
 995         DataPos64 = DataPosInt;
 996         DataPos64 <<= FRACTIONBITS;
 997         DataPos64 += DataPosFrac;
 998         BufferSize = (ALuint)((DataSize64-DataPos64+(increment-1)) / increment);
 999
1000         BufferSize = min(BufferSize, (SamplesToDo-j));
1001
1002         /* Actual sample mixing loop */
1003         k = 0;
1004         Data += DataPosInt*Channels;
1005
1006         if(Channels == 1) /* Mono */
1007         {
1008             ALfloat outsamp;
1009
1010             while(BufferSize--)
1011             {
1012                 for(i = 0;i < OUTPUTCHANNELS;i++)
1013                     DrySend[i] += dryGainStep[i];
1014                 for(i = 0;i < MAX_SENDS;i++)
1015                     WetSend[i] += wetGainStep[i];
1016
1017                 /* First order interpolator */
1018                 value = lerp(Data[k], Data[k+1], DataPosFrac);
1019
1020                 /* Direct path final mix buffer and panning */
1021                 outsamp = lpFilter4P(DryFilter, 0, value);
1022                 DryBuffer[j][FRONT_LEFT]   += outsamp*DrySend[FRONT_LEFT];
1023                 DryBuffer[j][FRONT_RIGHT]  += outsamp*DrySend[FRONT_RIGHT];
1024                 DryBuffer[j][SIDE_LEFT]    += outsamp*DrySend[SIDE_LEFT];
1025                 DryBuffer[j][SIDE_RIGHT]   += outsamp*DrySend[SIDE_RIGHT];
1026                 DryBuffer[j][BACK_LEFT]    += outsamp*DrySend[BACK_LEFT];
1027                 DryBuffer[j][BACK_RIGHT]   += outsamp*DrySend[BACK_RIGHT];
1028                 DryBuffer[j][FRONT_CENTER] += outsamp*DrySend[FRONT_CENTER];
1029                 DryBuffer[j][BACK_CENTER]  += outsamp*DrySend[BACK_CENTER];
1030
1031                 /* Room path final mix buffer and panning */
1032                 for(i = 0;i < MAX_SENDS;i++)
1033                 {
1034                     outsamp = lpFilter2P(WetFilter[i], 0, value);
1035                     WetBuffer[i][j] += outsamp*WetSend[i];
1036                 }
1037
1038                 DataPosFrac += increment;
1039                 k += DataPosFrac>>FRACTIONBITS;
1040                 DataPosFrac &= FRACTIONMASK;
1041                 j++;
1042             }
1043         }
1044         else if(Channels == 2) /* Stereo */
1045         {
1046             const int chans[] = {
1047                 FRONT_LEFT, FRONT_RIGHT
1048             };
1049
1050 #define DO_MIX() do { \
1051     for(i = 0;i < MAX_SENDS;i++) \
1052         WetSend[i] += wetGainStep[i]*BufferSize; \
1053     while(BufferSize--) \
1054     { \
1055         for(i = 0;i < OUTPUTCHANNELS;i++) \
1056             DrySend[i] += dryGainStep[i]; \
1057  \
1058         for(i = 0;i < Channels;i++) \
1059         { \
1060             value = lerp(Data[k*Channels + i], Data[(k+1)*Channels + i], DataPosFrac); \
1061             value = lpFilter2P(DryFilter, chans[i]*2, value)*DrySend[chans[i]]; \
1062             for(out = 0;out < OUTPUTCHANNELS;out++) \
1063                 DryBuffer[j][out] += value*Matrix[chans[i]][out]; \
1064         } \
1065  \
1066         DataPosFrac += increment; \
1067         k += DataPosFrac>>FRACTIONBITS; \
1068         DataPosFrac &= FRACTIONMASK; \
1069         j++; \
1070     } \
1071 } while(0)
1072
1073             DO_MIX();
1074         }
1075         else if(Channels == 4) /* Quad */
1076         {
1077             const int chans[] = {
1078                 FRONT_LEFT, FRONT_RIGHT,
1079                 BACK_LEFT,  BACK_RIGHT
1080             };
1081
1082             DO_MIX();
1083         }
1084         else if(Channels == 6) /* 5.1 */
1085         {
1086             const int chans[] = {
1087                 FRONT_LEFT,   FRONT_RIGHT,
1088                 FRONT_CENTER, LFE,
1089                 BACK_LEFT,    BACK_RIGHT
1090             };
1091
1092             DO_MIX();
1093         }
1094         else if(Channels == 7) /* 6.1 */
1095         {
1096             const int chans[] = {
1097                 FRONT_LEFT,   FRONT_RIGHT,
1098                 FRONT_CENTER, LFE,
1099                 BACK_CENTER,
1100                 SIDE_LEFT,    SIDE_RIGHT
1101             };
1102
1103             DO_MIX();
1104         }
1105         else if(Channels == 8) /* 7.1 */
1106         {
1107             const int chans[] = {
1108                 FRONT_LEFT,   FRONT_RIGHT,
1109                 FRONT_CENTER, LFE,
1110                 BACK_LEFT,    BACK_RIGHT,
1111                 SIDE_LEFT,    SIDE_RIGHT
1112             };
1113
1114             DO_MIX();
1115 #undef DO_MIX
1116         }
1117         else /* Unknown? */
1118         {
1119             for(i = 0;i < OUTPUTCHANNELS;i++)
1120                 DrySend[i] += dryGainStep[i]*BufferSize;
1121             for(i = 0;i < MAX_SENDS;i++)
1122                 WetSend[i] += wetGainStep[i]*BufferSize;
1123             while(BufferSize--)
1124             {
1125                 DataPosFrac += increment;
1126                 k += DataPosFrac>>FRACTIONBITS;
1127                 DataPosFrac &= FRACTIONMASK;
1128                 j++;
1129             }
1130         }
1131         DataPosInt += k;
1132
1133     skipmix:
1134         /* Handle looping sources */
1135         if(DataPosInt >= DataSize)
1136         {
1137             if(BuffersPlayed < (ALSource->BuffersInQueue-1))
1138             {
1139                 BufferListItem = BufferListItem->next;
1140                 BuffersPlayed++;
1141                 DataPosInt -= DataSize;
1142             }
1143             else
1144             {
1145                 if(!ALSource->bLooping)
1146                 {
1147                     State = AL_STOPPED;
1148                     BufferListItem = ALSource->queue;
1149                     BuffersPlayed = ALSource->BuffersInQueue;
1150                     DataPosInt = 0;
1151                     DataPosFrac = 0;
1152                 }
1153                 else
1154                 {
1155                     BufferListItem = ALSource->queue;
1156                     BuffersPlayed = 0;
1157                     if(ALSource->BuffersInQueue == 1)
1158                         DataPosInt %= DataSize;
1159                     else
1160                         DataPosInt -= DataSize;
1161                 }
1162             }
1163         }
1164     }
1165
1166     /* Update source info */
1167     ALSource->state             = State;
1168     ALSource->BuffersPlayed     = BuffersPlayed;
1169     ALSource->position          = DataPosInt;
1170     ALSource->position_fraction = DataPosFrac;
1171     ALSource->Buffer            = BufferListItem->buffer;
1172
1173     for(i = 0;i < OUTPUTCHANNELS;i++)
1174         ALSource->DryGains[i] = DrySend[i];
1175     for(i = 0;i < MAX_SENDS;i++)
1176         ALSource->WetGains[i] = WetSend[i];
1177
1178     ALSource->FirstStart = AL_FALSE;
1179
1180     if((ALSource=ALSource->next) != NULL)
1181         goto another_source;
1182 }
1183
1184 ALvoid aluMixData(ALCdevice *device, ALvoid *buffer, ALsizei size)
1185 {
1186     float (*DryBuffer)[OUTPUTCHANNELS];
1187     ALuint SamplesToDo;
1188     ALeffectslot *ALEffectSlot;
1189     ALCcontext *ALContext;
1190     int fpuState;
1191     ALuint i, c;
1192
1193     SuspendContext(NULL);
1194
1195 #if defined(HAVE_FESETROUND)
1196     fpuState = fegetround();
1197     fesetround(FE_TOWARDZERO);
1198 #elif defined(HAVE__CONTROLFP)
1199     fpuState = _controlfp(0, 0);
1200     _controlfp(_RC_CHOP, _MCW_RC);
1201 #else
1202     (void)fpuState;
1203 #endif
1204
1205     DryBuffer = device->DryBuffer;
1206     while(size > 0)
1207     {
1208         /* Setup variables */
1209         SamplesToDo = min(size, BUFFERSIZE);
1210
1211         /* Clear mixing buffer */
1212         memset(DryBuffer, 0, SamplesToDo*OUTPUTCHANNELS*sizeof(ALfloat));
1213
1214         for(c = 0;c < device->NumContexts;c++)
1215         {
1216             ALContext = device->Contexts[c];
1217             SuspendContext(ALContext);
1218
1219             MixSomeSources(ALContext, DryBuffer, SamplesToDo);
1220
1221             /* effect slot processing */
1222             ALEffectSlot = ALContext->AuxiliaryEffectSlot;
1223             while(ALEffectSlot)
1224             {
1225                 if(ALEffectSlot->EffectState)
1226                     ALEffect_Process(ALEffectSlot->EffectState, ALEffectSlot, SamplesToDo, ALEffectSlot->WetBuffer, DryBuffer);
1227
1228                 for(i = 0;i < SamplesToDo;i++)
1229                     ALEffectSlot->WetBuffer[i] = 0.0f;
1230                 ALEffectSlot = ALEffectSlot->next;
1231             }
1232             ProcessContext(ALContext);
1233         }
1234
1235         //Post processing loop
1236         switch(device->Format)
1237         {
1238 #define CHECK_WRITE_FORMAT(bits, type, func, isWin)                           \
1239         case AL_FORMAT_MONO##bits:                                            \
1240             for(i = 0;i < SamplesToDo;i++)                                    \
1241             {                                                                 \
1242                 ((type*)buffer)[0] = (func)(DryBuffer[i][FRONT_LEFT] +        \
1243                                             DryBuffer[i][FRONT_RIGHT]);       \
1244                 buffer = ((type*)buffer) + 1;                                 \
1245             }                                                                 \
1246             break;                                                            \
1247         case AL_FORMAT_STEREO##bits:                                          \
1248             if(device->Bs2b)                                                  \
1249             {                                                                 \
1250                 for(i = 0;i < SamplesToDo;i++)                                \
1251                 {                                                             \
1252                     float samples[2];                                         \
1253                     samples[0] = DryBuffer[i][FRONT_LEFT];                    \
1254                     samples[1] = DryBuffer[i][FRONT_RIGHT];                   \
1255                     bs2b_cross_feed(device->Bs2b, samples);                   \
1256                     ((type*)buffer)[0] = (func)(samples[0]);                  \
1257                     ((type*)buffer)[1] = (func)(samples[1]);                  \
1258                     buffer = ((type*)buffer) + 2;                             \
1259                 }                                                             \
1260             }                                                                 \
1261             else                                                              \
1262             {                                                                 \
1263                 for(i = 0;i < SamplesToDo;i++)                                \
1264                 {                                                             \
1265                     ((type*)buffer)[0] = (func)(DryBuffer[i][FRONT_LEFT]);    \
1266                     ((type*)buffer)[1] = (func)(DryBuffer[i][FRONT_RIGHT]);   \
1267                     buffer = ((type*)buffer) + 2;                             \
1268                 }                                                             \
1269             }                                                                 \
1270             break;                                                            \
1271         case AL_FORMAT_QUAD##bits:                                            \
1272             for(i = 0;i < SamplesToDo;i++)                                    \
1273             {                                                                 \
1274                 ((type*)buffer)[0] = (func)(DryBuffer[i][FRONT_LEFT]);        \
1275                 ((type*)buffer)[1] = (func)(DryBuffer[i][FRONT_RIGHT]);       \
1276                 ((type*)buffer)[2] = (func)(DryBuffer[i][BACK_LEFT]);         \
1277                 ((type*)buffer)[3] = (func)(DryBuffer[i][BACK_RIGHT]);        \
1278                 buffer = ((type*)buffer) + 4;                                 \
1279             }                                                                 \
1280             break;                                                            \
1281         case AL_FORMAT_51CHN##bits:                                           \
1282             for(i = 0;i < SamplesToDo;i++)                                    \
1283             {                                                                 \
1284                 ((type*)buffer)[0] = (func)(DryBuffer[i][FRONT_LEFT]);        \
1285                 ((type*)buffer)[1] = (func)(DryBuffer[i][FRONT_RIGHT]);       \
1286                 if(isWin) {                                                   \
1287                     /* Of course, Windows can't use the same ordering... */   \
1288                     ((type*)buffer)[2] = (func)(DryBuffer[i][FRONT_CENTER]);  \
1289                     ((type*)buffer)[3] = (func)(DryBuffer[i][LFE]);           \
1290                     ((type*)buffer)[4] = (func)(DryBuffer[i][BACK_LEFT]);     \
1291                     ((type*)buffer)[5] = (func)(DryBuffer[i][BACK_RIGHT]);    \
1292                 } else {                                                      \
1293                     ((type*)buffer)[2] = (func)(DryBuffer[i][BACK_LEFT]);     \
1294                     ((type*)buffer)[3] = (func)(DryBuffer[i][BACK_RIGHT]);    \
1295                     ((type*)buffer)[4] = (func)(DryBuffer[i][FRONT_CENTER]);  \
1296                     ((type*)buffer)[5] = (func)(DryBuffer[i][LFE]);           \
1297                 }                                                             \
1298                 buffer = ((type*)buffer) + 6;                                 \
1299             }                                                                 \
1300             break;                                                            \
1301         case AL_FORMAT_61CHN##bits:                                           \
1302             for(i = 0;i < SamplesToDo;i++)                                    \
1303             {                                                                 \
1304                 ((type*)buffer)[0] = (func)(DryBuffer[i][FRONT_LEFT]);        \
1305                 ((type*)buffer)[1] = (func)(DryBuffer[i][FRONT_RIGHT]);       \
1306                 ((type*)buffer)[2] = (func)(DryBuffer[i][FRONT_CENTER]);      \
1307                 ((type*)buffer)[3] = (func)(DryBuffer[i][LFE]);               \
1308                 ((type*)buffer)[4] = (func)(DryBuffer[i][BACK_CENTER]);       \
1309                 ((type*)buffer)[5] = (func)(DryBuffer[i][SIDE_LEFT]);         \
1310                 ((type*)buffer)[6] = (func)(DryBuffer[i][SIDE_RIGHT]);        \
1311                 buffer = ((type*)buffer) + 7;                                 \
1312             }                                                                 \
1313             break;                                                            \
1314         case AL_FORMAT_71CHN##bits:                                           \
1315             for(i = 0;i < SamplesToDo;i++)                                    \
1316             {                                                                 \
1317                 ((type*)buffer)[0] = (func)(DryBuffer[i][FRONT_LEFT]);        \
1318                 ((type*)buffer)[1] = (func)(DryBuffer[i][FRONT_RIGHT]);       \
1319                 if(isWin) {                                                   \
1320                     ((type*)buffer)[2] = (func)(DryBuffer[i][FRONT_CENTER]);  \
1321                     ((type*)buffer)[3] = (func)(DryBuffer[i][LFE]);           \
1322                     ((type*)buffer)[4] = (func)(DryBuffer[i][BACK_LEFT]);     \
1323                     ((type*)buffer)[5] = (func)(DryBuffer[i][BACK_RIGHT]);    \
1324                 } else {                                                      \
1325                     ((type*)buffer)[2] = (func)(DryBuffer[i][BACK_LEFT]);     \
1326                     ((type*)buffer)[3] = (func)(DryBuffer[i][BACK_RIGHT]);    \
1327                     ((type*)buffer)[4] = (func)(DryBuffer[i][FRONT_CENTER]);  \
1328                     ((type*)buffer)[5] = (func)(DryBuffer[i][LFE]);           \
1329                 }                                                             \
1330                 ((type*)buffer)[6] = (func)(DryBuffer[i][SIDE_LEFT]);         \
1331                 ((type*)buffer)[7] = (func)(DryBuffer[i][SIDE_RIGHT]);        \
1332                 buffer = ((type*)buffer) + 8;                                 \
1333             }                                                                 \
1334             break;
1335
1336 #define AL_FORMAT_MONO32 AL_FORMAT_MONO_FLOAT32
1337 #define AL_FORMAT_STEREO32 AL_FORMAT_STEREO_FLOAT32
1338 #ifdef _WIN32
1339             CHECK_WRITE_FORMAT(8,  ALubyte, aluF2UB, 1)
1340             CHECK_WRITE_FORMAT(16, ALshort, aluF2S, 1)
1341             CHECK_WRITE_FORMAT(32, ALfloat, aluF2F, 1)
1342 #else
1343             CHECK_WRITE_FORMAT(8,  ALubyte, aluF2UB, 0)
1344             CHECK_WRITE_FORMAT(16, ALshort, aluF2S, 0)
1345             CHECK_WRITE_FORMAT(32, ALfloat, aluF2F, 0)
1346 #endif
1347 #undef AL_FORMAT_STEREO32
1348 #undef AL_FORMAT_MONO32
1349 #undef CHECK_WRITE_FORMAT
1350
1351             default:
1352                 break;
1353         }
1354
1355         size -= SamplesToDo;
1356     }
1357
1358 #if defined(HAVE_FESETROUND)
1359     fesetround(fpuState);
1360 #elif defined(HAVE__CONTROLFP)
1361     _controlfp(fpuState, 0xfffff);
1362 #endif
1363
1364     ProcessContext(NULL);
1365 }
1366
1367 ALvoid aluHandleDisconnect(ALCdevice *device)
1368 {
1369     ALuint i;
1370
1371     SuspendContext(NULL);
1372     for(i = 0;i < device->NumContexts;i++)
1373     {
1374         ALsource *source;
1375
1376         SuspendContext(device->Contexts[i]);
1377
1378         source = device->Contexts[i]->Source;
1379         while(source)
1380         {
1381             if(source->state == AL_PLAYING)
1382             {
1383                 source->state = AL_STOPPED;
1384                 source->BuffersPlayed = source->BuffersInQueue;
1385                 source->position = 0;
1386                 source->position_fraction = 0;
1387             }
1388             source = source->next;
1389         }
1390         ProcessContext(device->Contexts[i]);
1391     }
1392
1393     device->Connected = ALC_FALSE;
1394     ProcessContext(NULL);
1395 }