snd_mix.c

   1 /*
   2 Copyright (C) 1996-1997 Id Software, Inc.
   3
   4 This program is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU General Public License
   6 as published by the Free Software Foundation; either version 2
   7 of the License, or (at your option) any later version.
   8
   9 This program 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.
  12
  13 See the GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18
  19 */
  20
  21 #include "quakedef.h"
  22 #include "snd_main.h"
  23
  24
  25 typedef struct portable_samplepair_s
  26 {
  27         int sample[SND_LISTENERS];
  28 } portable_sampleframe_t;
  29
  30 // LordHavoc: was 512, expanded to 2048
  31 #define PAINTBUFFER_SIZE 2048
  32 portable_sampleframe_t paintbuffer[PAINTBUFFER_SIZE];
  33
  34
  35 extern void SCR_CaptureVideo_SoundFrame(unsigned char *bufstereo16le, size_t length, int rate);
  36 static void S_CaptureAVISound(size_t length)
  37 {
  38         size_t i;
  39         unsigned char out[PAINTBUFFER_SIZE * 4];
  40         unsigned char* out_ptr;
  41
  42         if (!cls.capturevideo.active)
  43                 return;
  44
  45         // write the sound buffer as little endian 16bit interleaved stereo
  46         for(i = 0, out_ptr = out; i < length; i++, out_ptr += 4)
  47         {
  48                 int n0, n1;
  49
  50                 n0 = paintbuffer[i].sample[0];
  51                 n0 = bound(-32768, n0, 32767);
  52                 out_ptr[0] = (unsigned char)n0;
  53                 out_ptr[1] = (unsigned char)(n0 >> 8);
  54
  55                 n1 = paintbuffer[i].sample[1];
  56                 n1 = bound(-32768, n1, 32767);
  57                 out_ptr[2] = (unsigned char)n1;
  58                 out_ptr[3] = (unsigned char)(n1 >> 8);
  59         }
  60         SCR_CaptureVideo_SoundFrame(out, length, snd_renderbuffer->format.speed);
  61 }
  62
  63 static unsigned int S_TransferPaintBuffer(snd_ringbuffer_t* rb, unsigned int starttime, unsigned int endtime)
  64 {
  65         unsigned int partialend;
  66
  67         // Lock submitbuffer
  68         if (!simsound && !SndSys_LockRenderBuffer())
  69                 return 0;
  70
  71         partialend = starttime;
  72         while (partialend < endtime)  // handle recirculating buffer issues
  73         {
  74                 unsigned int startoffset, maxframes, nbframes, i;
  75                 void *rb_ptr;
  76                 portable_sampleframe_t *painted_ptr;
  77                 int val;
  78
  79                 startoffset = partialend % rb->maxframes;
  80                 maxframes = rb->maxframes - startoffset;
  81                 nbframes = endtime - partialend;
  82                 if (nbframes > maxframes)
  83                         nbframes = maxframes;
  84
  85                 rb_ptr = &rb->ring[startoffset * rb->format.width * rb->format.channels];
  86                 painted_ptr = &paintbuffer[partialend - starttime];
  87
  88                 if (rb->format.width == 2)  // 16bit
  89                 {
  90                         short *snd_out = (short*)rb_ptr;
  91                         if (rb->format.channels == 8)  // 7.1 surround
  92                         {
  93                                 for (i = 0;i < nbframes;i++, painted_ptr++)
  94                                 {
  95                                         *snd_out++ = bound(-32768, painted_ptr->sample[0], 32767);
  96                                         *snd_out++ = bound(-32768, painted_ptr->sample[1], 32767);
  97                                         *snd_out++ = bound(-32768, painted_ptr->sample[2], 32767);
  98                                         *snd_out++ = bound(-32768, painted_ptr->sample[3], 32767);
  99                                         *snd_out++ = bound(-32768, painted_ptr->sample[4], 32767);
 100                                         *snd_out++ = bound(-32768, painted_ptr->sample[5], 32767);
 101                                         *snd_out++ = bound(-32768, painted_ptr->sample[6], 32767);
 102                                         *snd_out++ = bound(-32768, painted_ptr->sample[7], 32767);
 103                                 }
 104                         }
 105                         else if (rb->format.channels == 6)  // 5.1 surround
 106                         {
 107                                 for (i = 0; i < nbframes; i++, painted_ptr++)
 108                                 {
 109                                         *snd_out++ = bound(-32768, painted_ptr->sample[0], 32767);
 110                                         *snd_out++ = bound(-32768, painted_ptr->sample[1], 32767);
 111                                         *snd_out++ = bound(-32768, painted_ptr->sample[2], 32767);
 112                                         *snd_out++ = bound(-32768, painted_ptr->sample[3], 32767);
 113                                         *snd_out++ = bound(-32768, painted_ptr->sample[4], 32767);
 114                                         *snd_out++ = bound(-32768, painted_ptr->sample[5], 32767);
 115                                 }
 116                         }
 117                         else if (rb->format.channels == 4)  // 4.0 surround
 118                         {
 119                                 for (i = 0; i < nbframes; i++, painted_ptr++)
 120                                 {
 121                                         *snd_out++ = bound(-32768, painted_ptr->sample[0], 32767);
 122                                         *snd_out++ = bound(-32768, painted_ptr->sample[1], 32767);
 123                                         *snd_out++ = bound(-32768, painted_ptr->sample[2], 32767);
 124                                         *snd_out++ = bound(-32768, painted_ptr->sample[3], 32767);
 125                                 }
 126                         }
 127                         else if (rb->format.channels == 2)  // 2.0 stereo
 128                         {
 129                                 for (i = 0; i < nbframes; i++, painted_ptr++)
 130                                 {
 131                                         *snd_out++ = bound(-32768, painted_ptr->sample[0], 32767);
 132                                         *snd_out++ = bound(-32768, painted_ptr->sample[1], 32767);
 133                                 }
 134                         }
 135                         else if (rb->format.channels == 1)  // 1.0 mono
 136                         {
 137                                 for (i = 0; i < nbframes; i++, painted_ptr++)
 138                                 {
 139                                         val = (painted_ptr->sample[0] + painted_ptr->sample[1]) >> 1;
 140                                         *snd_out++ = bound(-32768, val, 32767);
 141                                 }
 142                         }
 143                 }
 144                 else  // 8bit
 145                 {
 146                         unsigned char *snd_out = (unsigned char*)rb_ptr;
 147                         if (rb->format.channels == 8)  // 7.1 surround
 148                         {
 149                                 for (i = 0; i < nbframes; i++, painted_ptr++)
 150                                 {
 151                                         val = (painted_ptr->sample[0] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 152                                         val = (painted_ptr->sample[1] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 153                                         val = (painted_ptr->sample[2] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 154                                         val = (painted_ptr->sample[3] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 155                                         val = (painted_ptr->sample[4] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 156                                         val = (painted_ptr->sample[5] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 157                                         val = (painted_ptr->sample[6] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 158                                         val = (painted_ptr->sample[7] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 159                                 }
 160                         }
 161                         else if (rb->format.channels == 6)  // 5.1 surround
 162                         {
 163                                 for (i = 0; i < nbframes; i++, painted_ptr++)
 164                                 {
 165                                         val = (painted_ptr->sample[0] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 166                                         val = (painted_ptr->sample[1] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 167                                         val = (painted_ptr->sample[2] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 168                                         val = (painted_ptr->sample[3] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 169                                         val = (painted_ptr->sample[4] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 170                                         val = (painted_ptr->sample[5] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 171                                 }
 172                         }
 173                         else if (rb->format.channels == 4)  // 4.0 surround
 174                         {
 175                                 for (i = 0; i < nbframes; i++, painted_ptr++)
 176                                 {
 177                                         val = (painted_ptr->sample[0] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 178                                         val = (painted_ptr->sample[1] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 179                                         val = (painted_ptr->sample[2] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 180                                         val = (painted_ptr->sample[3] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 181                                 }
 182                         }
 183                         else if (rb->format.channels == 2)  // 2.0 stereo
 184                         {
 185                                 for (i = 0; i < nbframes; i++, painted_ptr++)
 186                                 {
 187                                         val = (painted_ptr->sample[0] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 188                                         val = (painted_ptr->sample[1] >> 8) + 128; *snd_out++ = bound(0, val, 255);
 189                                 }
 190                         }
 191                         else if (rb->format.channels == 1)  // 1.0 mono
 192                         {
 193                                 for (i = 0;i < nbframes;i++, painted_ptr++)
 194                                 {
 195                                         val = ((painted_ptr->sample[0] + painted_ptr->sample[1]) >> 9) + 128;
 196                                         *snd_out++ = bound(0, val, 255);
 197                                 }
 198                         }
 199                 }
 200
 201                 partialend += nbframes;
 202         }
 203
 204         rb->endframe = endtime;
 205
 206         // Remove outdated samples from the ring buffer, if any
 207         if (rb->startframe < soundtime)
 208                 rb->startframe = soundtime;
 209
 210         if (!simsound)
 211                 SndSys_UnlockRenderBuffer();
 212
 213         return endtime - starttime;
 214 }
 215
 216
 217 /*
 218 ===============================================================================
 219
 220 CHANNEL MIXING
 221
 222 ===============================================================================
 223 */
 224
 225 static qboolean SND_PaintChannel (channel_t *ch, unsigned int count)
 226 {
 227         int snd_vol, vol[SND_LISTENERS];
 228         const snd_buffer_t *sb;
 229         unsigned int i, sb_offset;
 230
 231         // If this channel manages its own volume
 232         if (ch->flags & CHANNELFLAG_FULLVOLUME)
 233                 snd_vol = 256;
 234         else
 235                 snd_vol = (int)(volume.value * 256);
 236
 237         for (i = 0;i < SND_LISTENERS;i++)
 238                 vol[i] = ch->listener_volume[i] * snd_vol;
 239
 240         sb_offset = ch->pos;
 241         sb = ch->sfx->fetcher->getsb (ch, &sb_offset, count);
 242         if (sb == NULL)
 243         {
 244                 Con_DPrintf("SND_PaintChannel: ERROR: can't get sound buffer from sfx \"%s\"\n",
 245                                         ch->sfx->name); // , count); // or add this? FIXME
 246         }
 247         else
 248         {
 249 #if SND_LISTENERS != 8
 250 #               error the following code only supports up to 8 channels, update it
 251 #endif
 252                 if (sb->format.width == 1)
 253                 {
 254                         const signed char *samples = (signed char*)sb->samples + (ch->pos - sb_offset) * sb->format.channels;
 255
 256                         // Stereo sound support
 257                         if (sb->format.channels == 2)
 258                         {
 259                                 if (vol[6] + vol[7] > 0)
 260                                 {
 261                                         for (i = 0;i < count;i++)
 262                                         {
 263                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 8;
 264                                                 paintbuffer[i].sample[1] += (samples[1] * vol[1]) >> 8;
 265                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 8;
 266                                                 paintbuffer[i].sample[3] += (samples[1] * vol[3]) >> 8;
 267                                                 paintbuffer[i].sample[4] += ((samples[0] + samples[1]) * vol[4]) >> 9;
 268                                                 paintbuffer[i].sample[5] += ((samples[0] + samples[1]) * vol[5]) >> 9;
 269                                                 paintbuffer[i].sample[6] += (samples[0] * vol[6]) >> 8;
 270                                                 paintbuffer[i].sample[7] += (samples[1] * vol[7]) >> 8;
 271                                                 samples += 2;
 272                                         }
 273                                 }
 274                                 else if (vol[4] + vol[5] > 0)
 275                                 {
 276                                         for (i = 0;i < count;i++)
 277                                         {
 278                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 8;
 279                                                 paintbuffer[i].sample[1] += (samples[1] * vol[1]) >> 8;
 280                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 8;
 281                                                 paintbuffer[i].sample[3] += (samples[1] * vol[3]) >> 8;
 282                                                 paintbuffer[i].sample[4] += ((samples[0] + samples[1]) * vol[4]) >> 9;
 283                                                 paintbuffer[i].sample[5] += ((samples[0] + samples[1]) * vol[5]) >> 9;
 284                                                 samples += 2;
 285                                         }
 286                                 }
 287                                 else if (vol[2] + vol[3] > 0)
 288                                 {
 289                                         for (i = 0;i < count;i++)
 290                                         {
 291                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 8;
 292                                                 paintbuffer[i].sample[1] += (samples[1] * vol[1]) >> 8;
 293                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 8;
 294                                                 paintbuffer[i].sample[3] += (samples[1] * vol[3]) >> 8;
 295                                                 samples += 2;
 296                                         }
 297                                 }
 298                                 else if (vol[0] + vol[1] > 0)
 299                                 {
 300                                         for (i = 0;i < count;i++)
 301                                         {
 302                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 8;
 303                                                 paintbuffer[i].sample[1] += (samples[1] * vol[1]) >> 8;
 304                                                 samples += 2;
 305                                         }
 306                                 }
 307                         }
 308                         else if (sb->format.channels == 1)
 309                         {
 310                                 if (vol[6] + vol[7] > 0)
 311                                 {
 312                                         for (i = 0;i < count;i++)
 313                                         {
 314                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 8;
 315                                                 paintbuffer[i].sample[1] += (samples[0] * vol[1]) >> 8;
 316                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 8;
 317                                                 paintbuffer[i].sample[3] += (samples[0] * vol[3]) >> 8;
 318                                                 paintbuffer[i].sample[4] += (samples[0] * vol[4]) >> 8;
 319                                                 paintbuffer[i].sample[5] += (samples[0] * vol[5]) >> 8;
 320                                                 paintbuffer[i].sample[6] += (samples[0] * vol[6]) >> 8;
 321                                                 paintbuffer[i].sample[7] += (samples[0] * vol[7]) >> 8;
 322                                                 samples += 1;
 323                                         }
 324                                 }
 325                                 else if (vol[4] + vol[5] > 0)
 326                                 {
 327                                         for (i = 0;i < count;i++)
 328                                         {
 329                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 8;
 330                                                 paintbuffer[i].sample[1] += (samples[0] * vol[1]) >> 8;
 331                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 8;
 332                                                 paintbuffer[i].sample[3] += (samples[0] * vol[3]) >> 8;
 333                                                 paintbuffer[i].sample[4] += (samples[0] * vol[4]) >> 8;
 334                                                 paintbuffer[i].sample[5] += (samples[0] * vol[5]) >> 8;
 335                                                 samples += 1;
 336                                         }
 337                                 }
 338                                 else if (vol[2] + vol[3] > 0)
 339                                 {
 340                                         for (i = 0;i < count;i++)
 341                                         {
 342                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 8;
 343                                                 paintbuffer[i].sample[1] += (samples[0] * vol[1]) >> 8;
 344                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 8;
 345                                                 paintbuffer[i].sample[3] += (samples[0] * vol[3]) >> 8;
 346                                                 samples += 1;
 347                                         }
 348                                 }
 349                                 else if (vol[0] + vol[1] > 0)
 350                                 {
 351                                         for (i = 0;i < count;i++)
 352                                         {
 353                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 8;
 354                                                 paintbuffer[i].sample[1] += (samples[0] * vol[1]) >> 8;
 355                                                 samples += 1;
 356                                         }
 357                                 }
 358                         }
 359                         else
 360                                 return false; // unsupported number of channels in sound
 361                 }
 362                 else if (sb->format.width == 2)
 363                 {
 364                         const signed short *samples = (signed short*)sb->samples + (ch->pos - sb_offset) * sb->format.channels;
 365
 366                         // Stereo sound support
 367                         if (sb->format.channels == 2)
 368                         {
 369                                 if (vol[6] + vol[7] > 0)
 370                                 {
 371                                         for (i = 0;i < count;i++)
 372                                         {
 373                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 16;
 374                                                 paintbuffer[i].sample[1] += (samples[1] * vol[1]) >> 16;
 375                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 16;
 376                                                 paintbuffer[i].sample[3] += (samples[1] * vol[3]) >> 16;
 377                                                 paintbuffer[i].sample[4] += ((samples[0] + samples[1]) * vol[4]) >> 17;
 378                                                 paintbuffer[i].sample[5] += ((samples[0] + samples[1]) * vol[5]) >> 17;
 379                                                 paintbuffer[i].sample[6] += (samples[0] * vol[6]) >> 16;
 380                                                 paintbuffer[i].sample[7] += (samples[1] * vol[7]) >> 16;
 381                                                 samples += 2;
 382                                         }
 383                                 }
 384                                 else if (vol[4] + vol[5] > 0)
 385                                 {
 386                                         for (i = 0;i < count;i++)
 387                                         {
 388                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 16;
 389                                                 paintbuffer[i].sample[1] += (samples[1] * vol[1]) >> 16;
 390                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 16;
 391                                                 paintbuffer[i].sample[3] += (samples[1] * vol[3]) >> 16;
 392                                                 paintbuffer[i].sample[4] += ((samples[0] + samples[1]) * vol[4]) >> 17;
 393                                                 paintbuffer[i].sample[5] += ((samples[0] + samples[1]) * vol[5]) >> 17;
 394                                                 samples += 2;
 395                                         }
 396                                 }
 397                                 else if (vol[2] + vol[3] > 0)
 398                                 {
 399                                         for (i = 0;i < count;i++)
 400                                         {
 401                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 16;
 402                                                 paintbuffer[i].sample[1] += (samples[1] * vol[1]) >> 16;
 403                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 16;
 404                                                 paintbuffer[i].sample[3] += (samples[1] * vol[3]) >> 16;
 405                                                 samples += 2;
 406                                         }
 407                                 }
 408                                 else if (vol[0] + vol[1] > 0)
 409                                 {
 410                                         for (i = 0;i < count;i++)
 411                                         {
 412                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 16;
 413                                                 paintbuffer[i].sample[1] += (samples[1] * vol[1]) >> 16;
 414                                                 samples += 2;
 415                                         }
 416                                 }
 417                         }
 418                         else if (sb->format.channels == 1)
 419                         {
 420                                 if (vol[6] + vol[7] > 0)
 421                                 {
 422                                         for (i = 0;i < count;i++)
 423                                         {
 424                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 16;
 425                                                 paintbuffer[i].sample[1] += (samples[0] * vol[1]) >> 16;
 426                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 16;
 427                                                 paintbuffer[i].sample[3] += (samples[0] * vol[3]) >> 16;
 428                                                 paintbuffer[i].sample[4] += (samples[0] * vol[4]) >> 16;
 429                                                 paintbuffer[i].sample[5] += (samples[0] * vol[5]) >> 16;
 430                                                 paintbuffer[i].sample[6] += (samples[0] * vol[6]) >> 16;
 431                                                 paintbuffer[i].sample[7] += (samples[0] * vol[7]) >> 16;
 432                                                 samples += 1;
 433                                         }
 434                                 }
 435                                 else if (vol[4] + vol[5] > 0)
 436                                 {
 437                                         for (i = 0;i < count;i++)
 438                                         {
 439                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 16;
 440                                                 paintbuffer[i].sample[1] += (samples[0] * vol[1]) >> 16;
 441                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 16;
 442                                                 paintbuffer[i].sample[3] += (samples[0] * vol[3]) >> 16;
 443                                                 paintbuffer[i].sample[4] += (samples[0] * vol[4]) >> 16;
 444                                                 paintbuffer[i].sample[5] += (samples[0] * vol[5]) >> 16;
 445                                                 samples += 1;
 446                                         }
 447                                 }
 448                                 else if (vol[2] + vol[3] > 0)
 449                                 {
 450                                         for (i = 0;i < count;i++)
 451                                         {
 452                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 16;
 453                                                 paintbuffer[i].sample[1] += (samples[0] * vol[1]) >> 16;
 454                                                 paintbuffer[i].sample[2] += (samples[0] * vol[2]) >> 16;
 455                                                 paintbuffer[i].sample[3] += (samples[0] * vol[3]) >> 16;
 456                                                 samples += 1;
 457                                         }
 458                                 }
 459                                 else if (vol[0] + vol[1] > 0)
 460                                 {
 461                                         for (i = 0;i < count;i++)
 462                                         {
 463                                                 paintbuffer[i].sample[0] += (samples[0] * vol[0]) >> 16;
 464                                                 paintbuffer[i].sample[1] += (samples[0] * vol[1]) >> 16;
 465                                                 samples += 1;
 466                                         }
 467                                 }
 468                         }
 469                         else
 470                                 return false; // unsupported number of channels in sound
 471                 }
 472         }
 473
 474         ch->pos += count;
 475         return true;
 476 }
 477
 478 void S_PaintChannels (snd_ringbuffer_t* rb, unsigned int starttime, unsigned int endtime)
 479 {
 480         unsigned int paintedtime;
 481
 482         paintedtime = starttime;
 483         while (paintedtime < endtime)
 484         {
 485                 unsigned int partialend, i, framecount;
 486                 channel_t *ch;
 487
 488                 // if paintbuffer is too small
 489                 if (endtime > paintedtime + PAINTBUFFER_SIZE)
 490                         partialend = paintedtime + PAINTBUFFER_SIZE;
 491                 else
 492                         partialend = endtime;
 493
 494                 // clear the paint buffer
 495                 memset (paintbuffer, 0, (partialend - paintedtime) * sizeof (paintbuffer[0]));
 496
 497                 // paint in the channels.
 498                 ch = channels;
 499                 for (i = 0; i < total_channels ; i++, ch++)
 500                 {
 501                         sfx_t *sfx;
 502                         unsigned int ltime, j;
 503
 504                         sfx = ch->sfx;
 505                         if (sfx == NULL)
 506                                 continue;
 507                         for (j = 0;j < SND_LISTENERS;j++)
 508                                 if (ch->listener_volume[j])
 509                                         break;
 510                         if (j == SND_LISTENERS)
 511                                 continue;
 512                         if (!S_LoadSound (sfx, true))
 513                                 continue;
 514
 515                         // if the channel is paused
 516                         if (ch->flags & CHANNELFLAG_PAUSED)
 517                         {
 518                                 int pausedtime = partialend - paintedtime;
 519                                 ch->lastptime += pausedtime;
 520                                 ch->end += pausedtime;
 521                                 continue;
 522                         }
 523
 524                         // if the sound hasn't been painted last time, update his position
 525                         if (ch->lastptime < paintedtime)
 526                         {
 527                                 ch->pos += paintedtime - ch->lastptime;
 528
 529                                 // If the sound should have ended by then
 530                                 if ((unsigned int)ch->pos > sfx->total_length)
 531                                 {
 532                                         int loopstart;
 533
 534                                         if (sfx->loopstart >= 0)
 535                                                 loopstart = bound(0, sfx->loopstart, (int)sfx->total_length - 1);
 536                                         else
 537                                         {
 538                                                 if (ch->flags & CHANNELFLAG_FORCELOOP)
 539                                                         loopstart = 0;
 540                                                 else
 541                                                         loopstart = -1;
 542                                         }
 543
 544                                         // If the sound is looped
 545                                         if (loopstart >= 0)
 546                                                 ch->pos = (ch->pos - sfx->total_length) % (sfx->total_length - loopstart) + loopstart;
 547                                         else
 548                                                 ch->pos = sfx->total_length;
 549                                         ch->end = paintedtime + sfx->total_length - ch->pos;
 550                                 }
 551                         }
 552
 553                         ltime = paintedtime;
 554                         while (ltime < partialend)
 555                         {
 556                                 int count;
 557                                 qboolean stop_paint;
 558
 559                                 // paint up to end
 560                                 if (ch->end < partialend)
 561                                         count = ch->end - ltime;
 562                                 else
 563                                         count = partialend - ltime;
 564
 565                                 if (count > 0)
 566                                 {
 567                                         for (j = 0; j < SND_LISTENERS; j++)
 568                                                 ch->listener_volume[j] = bound(0, ch->listener_volume[j], 255);
 569
 570                                         stop_paint = !SND_PaintChannel (ch, (unsigned int)count);
 571                                         if (!stop_paint)
 572                                         {
 573                                                 ltime += count;
 574                                                 ch->lastptime = ltime;
 575                                         }
 576                                 }
 577                                 else
 578                                         stop_paint = false;
 579
 580                                 if (ltime >= ch->end)
 581                                 {
 582                                         // if at end of loop, restart
 583                                         if ((sfx->loopstart >= 0 || (ch->flags & CHANNELFLAG_FORCELOOP)) && !stop_paint)
 584                                         {
 585                                                 ch->pos = bound(0, sfx->loopstart, (int)sfx->total_length - 1);
 586                                                 ch->end = ltime + sfx->total_length - ch->pos;
 587                                         }
 588                                         // channel just stopped
 589                                         else
 590                                                 stop_paint = true;
 591                                 }
 592
 593                                 if (stop_paint)
 594                                 {
 595                                         S_StopChannel (ch - channels);
 596                                         break;
 597                                 }
 598                         }
 599                 }
 600
 601                 S_CaptureAVISound (partialend - paintedtime);
 602                 framecount = S_TransferPaintBuffer (rb, paintedtime, partialend);
 603                 paintedtime += framecount;
 604
 605                 // If there was not enough free space in the sound buffer, stop here
 606                 if (paintedtime != partialend)
 607                 {
 608                         Con_DPrintf(">> S_PaintChannels: Not enough free space in the sound buffer ( %u != %u)\n", paintedtime, partialend);
 609                         break;
 610                 }
 611         }
 612 }