Alc/panning.c

   1 /**
   2  * OpenAL cross platform audio library
   3  * Copyright (C) 1999-2010 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 "alu.h"
  33
  34 static void SetSpeakerArrangement(const char *name, ALfloat SpeakerAngle[MAXCHANNELS],
  35                                   Channel Speaker2Chan[MAXCHANNELS], ALint chans)
  36 {
  37     char layout_str[256];
  38     char *confkey, *next;
  39     char *sep, *end;
  40     Channel val;
  41     int i;
  42
  43     if(!ConfigValueExists(NULL, name))
  44         name = "layout";
  45
  46     strncpy(layout_str, GetConfigValue(NULL, name, ""), sizeof(layout_str));
  47     layout_str[sizeof(layout_str)-1] = 0;
  48
  49     if(!layout_str[0])
  50         return;
  51
  52     next = confkey = layout_str;
  53     while(next && *next)
  54     {
  55         confkey = next;
  56         next = strchr(confkey, ',');
  57         if(next)
  58         {
  59             *next = 0;
  60             do {
  61                 next++;
  62             } while(isspace(*next) || *next == ',');
  63         }
  64
  65         sep = strchr(confkey, '=');
  66         if(!sep || confkey == sep)
  67             continue;
  68
  69         end = sep - 1;
  70         while(isspace(*end) && end != confkey)
  71             end--;
  72         *(++end) = 0;
  73
  74         if(strcmp(confkey, "fl") == 0 || strcmp(confkey, "front-left") == 0)
  75             val = FRONT_LEFT;
  76         else if(strcmp(confkey, "fr") == 0 || strcmp(confkey, "front-right") == 0)
  77             val = FRONT_RIGHT;
  78         else if(strcmp(confkey, "fc") == 0 || strcmp(confkey, "front-center") == 0)
  79             val = FRONT_CENTER;
  80         else if(strcmp(confkey, "bl") == 0 || strcmp(confkey, "back-left") == 0)
  81             val = BACK_LEFT;
  82         else if(strcmp(confkey, "br") == 0 || strcmp(confkey, "back-right") == 0)
  83             val = BACK_RIGHT;
  84         else if(strcmp(confkey, "bc") == 0 || strcmp(confkey, "back-center") == 0)
  85             val = BACK_CENTER;
  86         else if(strcmp(confkey, "sl") == 0 || strcmp(confkey, "side-left") == 0)
  87             val = SIDE_LEFT;
  88         else if(strcmp(confkey, "sr") == 0 || strcmp(confkey, "side-right") == 0)
  89             val = SIDE_RIGHT;
  90         else
  91         {
  92             AL_PRINT("Unknown speaker for %s: \"%s\"\n", name, confkey);
  93             continue;
  94         }
  95
  96         *(sep++) = 0;
  97         while(isspace(*sep))
  98             sep++;
  99
 100         for(i = 0;i < chans;i++)
 101         {
 102             if(Speaker2Chan[i] == val)
 103             {
 104                 long angle = strtol(sep, NULL, 10);
 105                 if(angle >= -180 && angle <= 180)
 106                     SpeakerAngle[i] = angle * M_PI/180.0f;
 107                 else
 108                     AL_PRINT("Invalid angle for speaker \"%s\": %ld\n", confkey, angle);
 109                 break;
 110             }
 111         }
 112     }
 113
 114     for(i = 0;i < chans;i++)
 115     {
 116         int min = i;
 117         int i2;
 118
 119         for(i2 = i+1;i2 < chans;i2++)
 120         {
 121             if(SpeakerAngle[i2] < SpeakerAngle[min])
 122                 min = i2;
 123         }
 124
 125         if(min != i)
 126         {
 127             ALfloat tmpf;
 128             Channel tmpc;
 129
 130             tmpf = SpeakerAngle[i];
 131             SpeakerAngle[i] = SpeakerAngle[min];
 132             SpeakerAngle[min] = tmpf;
 133
 134             tmpc = Speaker2Chan[i];
 135             Speaker2Chan[i] = Speaker2Chan[min];
 136             Speaker2Chan[min] = tmpc;
 137         }
 138     }
 139 }
 140
 141 static ALfloat aluLUTpos2Angle(ALint pos)
 142 {
 143     if(pos < QUADRANT_NUM)
 144         return aluAtan((ALfloat)pos / (ALfloat)(QUADRANT_NUM - pos));
 145     if(pos < 2 * QUADRANT_NUM)
 146         return M_PI_2 + aluAtan((ALfloat)(pos - QUADRANT_NUM) / (ALfloat)(2 * QUADRANT_NUM - pos));
 147     if(pos < 3 * QUADRANT_NUM)
 148         return aluAtan((ALfloat)(pos - 2 * QUADRANT_NUM) / (ALfloat)(3 * QUADRANT_NUM - pos)) - M_PI;
 149     return aluAtan((ALfloat)(pos - 3 * QUADRANT_NUM) / (ALfloat)(4 * QUADRANT_NUM - pos)) - M_PI_2;
 150 }
 151
 152 ALint aluCart2LUTpos(ALfloat re, ALfloat im)
 153 {
 154     ALint pos = 0;
 155     ALfloat denom = aluFabs(re) + aluFabs(im);
 156     if(denom > 0.0f)
 157         pos = (ALint)(QUADRANT_NUM*aluFabs(im) / denom + 0.5);
 158
 159     if(re < 0.0)
 160         pos = 2 * QUADRANT_NUM - pos;
 161     if(im < 0.0)
 162         pos = LUT_NUM - pos;
 163     return pos%LUT_NUM;
 164 }
 165
 166 ALvoid aluInitPanning(ALCdevice *Device)
 167 {
 168     ALfloat SpeakerAngle[MAXCHANNELS];
 169     ALfloat (*Matrix)[MAXCHANNELS];
 170     Channel *Speaker2Chan;
 171     ALfloat Alpha, Theta;
 172     ALfloat *PanningLUT;
 173     ALint pos, offset;
 174     ALuint s, s2;
 175
 176     for(s = 0;s < MAXCHANNELS;s++)
 177     {
 178         for(s2 = 0;s2 < MAXCHANNELS;s2++)
 179             Device->ChannelMatrix[s][s2] = ((s==s2) ? 1.0f : 0.0f);
 180     }
 181
 182     Speaker2Chan = Device->Speaker2Chan;
 183     Matrix = Device->ChannelMatrix;
 184     switch(Device->FmtChans)
 185     {
 186         case DevFmtMono:
 187             Matrix[FRONT_LEFT][FRONT_CENTER]  = aluSqrt(0.5);
 188             Matrix[FRONT_RIGHT][FRONT_CENTER] = aluSqrt(0.5);
 189             Matrix[SIDE_LEFT][FRONT_CENTER]   = aluSqrt(0.5);
 190             Matrix[SIDE_RIGHT][FRONT_CENTER]  = aluSqrt(0.5);
 191             Matrix[BACK_LEFT][FRONT_CENTER]   = aluSqrt(0.5);
 192             Matrix[BACK_RIGHT][FRONT_CENTER]  = aluSqrt(0.5);
 193             Matrix[BACK_CENTER][FRONT_CENTER] = 1.0f;
 194             Device->NumChan = 1;
 195             Speaker2Chan[0] = FRONT_CENTER;
 196             SpeakerAngle[0] = 0.0f * M_PI/180.0f;
 197             break;
 198
 199         case DevFmtStereo:
 200             Matrix[FRONT_CENTER][FRONT_LEFT]  = aluSqrt(0.5);
 201             Matrix[FRONT_CENTER][FRONT_RIGHT] = aluSqrt(0.5);
 202             Matrix[SIDE_LEFT][FRONT_LEFT]     = 1.0f;
 203             Matrix[SIDE_RIGHT][FRONT_RIGHT]   = 1.0f;
 204             Matrix[BACK_LEFT][FRONT_LEFT]     = 1.0f;
 205             Matrix[BACK_RIGHT][FRONT_RIGHT]   = 1.0f;
 206             Matrix[BACK_CENTER][FRONT_LEFT]   = aluSqrt(0.5);
 207             Matrix[BACK_CENTER][FRONT_RIGHT]  = aluSqrt(0.5);
 208             Device->NumChan = 2;
 209             Speaker2Chan[0] = FRONT_LEFT;
 210             Speaker2Chan[1] = FRONT_RIGHT;
 211             SpeakerAngle[0] = -90.0f * M_PI/180.0f;
 212             SpeakerAngle[1] =  90.0f * M_PI/180.0f;
 213             SetSpeakerArrangement("layout_STEREO", SpeakerAngle, Speaker2Chan, Device->NumChan);
 214             break;
 215
 216         case DevFmtQuad:
 217             Matrix[FRONT_CENTER][FRONT_LEFT]  = aluSqrt(0.5);
 218             Matrix[FRONT_CENTER][FRONT_RIGHT] = aluSqrt(0.5);
 219             Matrix[SIDE_LEFT][FRONT_LEFT]     = aluSqrt(0.5);
 220             Matrix[SIDE_LEFT][BACK_LEFT]      = aluSqrt(0.5);
 221             Matrix[SIDE_RIGHT][FRONT_RIGHT]   = aluSqrt(0.5);
 222             Matrix[SIDE_RIGHT][BACK_RIGHT]    = aluSqrt(0.5);
 223             Matrix[BACK_CENTER][BACK_LEFT]    = aluSqrt(0.5);
 224             Matrix[BACK_CENTER][BACK_RIGHT]   = aluSqrt(0.5);
 225             Device->NumChan = 4;
 226             Speaker2Chan[0] = BACK_LEFT;
 227             Speaker2Chan[1] = FRONT_LEFT;
 228             Speaker2Chan[2] = FRONT_RIGHT;
 229             Speaker2Chan[3] = BACK_RIGHT;
 230             SpeakerAngle[0] = -135.0f * M_PI/180.0f;
 231             SpeakerAngle[1] =  -45.0f * M_PI/180.0f;
 232             SpeakerAngle[2] =   45.0f * M_PI/180.0f;
 233             SpeakerAngle[3] =  135.0f * M_PI/180.0f;
 234             SetSpeakerArrangement("layout_QUAD", SpeakerAngle, Speaker2Chan, Device->NumChan);
 235             break;
 236
 237         case DevFmtX51:
 238             Matrix[SIDE_LEFT][FRONT_LEFT]   = aluSqrt(0.5);
 239             Matrix[SIDE_LEFT][BACK_LEFT]    = aluSqrt(0.5);
 240             Matrix[SIDE_RIGHT][FRONT_RIGHT] = aluSqrt(0.5);
 241             Matrix[SIDE_RIGHT][BACK_RIGHT]  = aluSqrt(0.5);
 242             Matrix[BACK_CENTER][BACK_LEFT]  = aluSqrt(0.5);
 243             Matrix[BACK_CENTER][BACK_RIGHT] = aluSqrt(0.5);
 244             Device->NumChan = 5;
 245             Speaker2Chan[0] = BACK_LEFT;
 246             Speaker2Chan[1] = FRONT_LEFT;
 247             Speaker2Chan[2] = FRONT_CENTER;
 248             Speaker2Chan[3] = FRONT_RIGHT;
 249             Speaker2Chan[4] = BACK_RIGHT;
 250             SpeakerAngle[0] = -110.0f * M_PI/180.0f;
 251             SpeakerAngle[1] =  -30.0f * M_PI/180.0f;
 252             SpeakerAngle[2] =    0.0f * M_PI/180.0f;
 253             SpeakerAngle[3] =   30.0f * M_PI/180.0f;
 254             SpeakerAngle[4] =  110.0f * M_PI/180.0f;
 255             SetSpeakerArrangement("layout_51CHN", SpeakerAngle, Speaker2Chan, Device->NumChan);
 256             break;
 257
 258         case DevFmtX61:
 259             Matrix[BACK_LEFT][BACK_CENTER]  = aluSqrt(0.5);
 260             Matrix[BACK_LEFT][SIDE_LEFT]    = aluSqrt(0.5);
 261             Matrix[BACK_RIGHT][BACK_CENTER] = aluSqrt(0.5);
 262             Matrix[BACK_RIGHT][SIDE_RIGHT]  = aluSqrt(0.5);
 263             Device->NumChan = 6;
 264             Speaker2Chan[0] = SIDE_LEFT;
 265             Speaker2Chan[1] = FRONT_LEFT;
 266             Speaker2Chan[2] = FRONT_CENTER;
 267             Speaker2Chan[3] = FRONT_RIGHT;
 268             Speaker2Chan[4] = SIDE_RIGHT;
 269             Speaker2Chan[5] = BACK_CENTER;
 270             SpeakerAngle[0] = -90.0f * M_PI/180.0f;
 271             SpeakerAngle[1] = -30.0f * M_PI/180.0f;
 272             SpeakerAngle[2] =   0.0f * M_PI/180.0f;
 273             SpeakerAngle[3] =  30.0f * M_PI/180.0f;
 274             SpeakerAngle[4] =  90.0f * M_PI/180.0f;
 275             SpeakerAngle[5] = 180.0f * M_PI/180.0f;
 276             SetSpeakerArrangement("layout_61CHN", SpeakerAngle, Speaker2Chan, Device->NumChan);
 277             break;
 278
 279         case DevFmtX71:
 280             Matrix[BACK_CENTER][BACK_LEFT]  = aluSqrt(0.5);
 281             Matrix[BACK_CENTER][BACK_RIGHT] = aluSqrt(0.5);
 282             Device->NumChan = 7;
 283             Speaker2Chan[0] = BACK_LEFT;
 284             Speaker2Chan[1] = SIDE_LEFT;
 285             Speaker2Chan[2] = FRONT_LEFT;
 286             Speaker2Chan[3] = FRONT_CENTER;
 287             Speaker2Chan[4] = FRONT_RIGHT;
 288             Speaker2Chan[5] = SIDE_RIGHT;
 289             Speaker2Chan[6] = BACK_RIGHT;
 290             SpeakerAngle[0] = -150.0f * M_PI/180.0f;
 291             SpeakerAngle[1] =  -90.0f * M_PI/180.0f;
 292             SpeakerAngle[2] =  -30.0f * M_PI/180.0f;
 293             SpeakerAngle[3] =    0.0f * M_PI/180.0f;
 294             SpeakerAngle[4] =   30.0f * M_PI/180.0f;
 295             SpeakerAngle[5] =   90.0f * M_PI/180.0f;
 296             SpeakerAngle[6] =  150.0f * M_PI/180.0f;
 297             SetSpeakerArrangement("layout_71CHN", SpeakerAngle, Speaker2Chan, Device->NumChan);
 298             break;
 299     }
 300
 301     if(GetConfigValueBool(NULL, "scalemix", 0))
 302     {
 303         ALfloat maxout = 1.0f;
 304         for(s = 0;s < MAXCHANNELS;s++)
 305         {
 306             ALfloat out = 0.0f;
 307             for(s2 = 0;s2 < MAXCHANNELS;s2++)
 308                 out += Device->ChannelMatrix[s2][s];
 309             maxout = __max(maxout, out);
 310         }
 311
 312         maxout = 1.0f/maxout;
 313         for(s = 0;s < MAXCHANNELS;s++)
 314         {
 315             for(s2 = 0;s2 < MAXCHANNELS;s2++)
 316                 Device->ChannelMatrix[s2][s] *= maxout;
 317         }
 318     }
 319
 320     PanningLUT = Device->PanningLUT;
 321     for(pos = 0; pos < LUT_NUM; pos++)
 322     {
 323         /* clear all values */
 324         offset = MAXCHANNELS * pos;
 325         for(s = 0; s < MAXCHANNELS; s++)
 326             PanningLUT[offset+s] = 0.0f;
 327
 328         if(Device->NumChan == 1)
 329         {
 330             PanningLUT[offset + Speaker2Chan[0]] = 1.0f;
 331             continue;
 332         }
 333
 334         /* source angle */
 335         Theta = aluLUTpos2Angle(pos);
 336
 337         /* set panning values */
 338         for(s = 0; s < Device->NumChan - 1; s++)
 339         {
 340             if(Theta >= SpeakerAngle[s] && Theta < SpeakerAngle[s+1])
 341             {
 342                 /* source between speaker s and speaker s+1 */
 343                 Alpha = M_PI_2 * (Theta-SpeakerAngle[s]) /
 344                                  (SpeakerAngle[s+1]-SpeakerAngle[s]);
 345                 PanningLUT[offset + Speaker2Chan[s]]   = cos(Alpha);
 346                 PanningLUT[offset + Speaker2Chan[s+1]] = sin(Alpha);
 347                 break;
 348             }
 349         }
 350         if(s == Device->NumChan - 1)
 351         {
 352             /* source between last and first speaker */
 353             if(Theta < SpeakerAngle[0])
 354                 Theta += 2.0f * M_PI;
 355             Alpha = M_PI_2 * (Theta-SpeakerAngle[s]) /
 356                              (2.0f * M_PI + SpeakerAngle[0]-SpeakerAngle[s]);
 357             PanningLUT[offset + Speaker2Chan[s]] = cos(Alpha);
 358             PanningLUT[offset + Speaker2Chan[0]] = sin(Alpha);
 359         }
 360     }
 361 }