snd_mem.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 // snd_mem.c: sound caching
  21
  22 #include "quakedef.h"
  23
  24 int                     cache_full_cycle;
  25
  26 byte *S_Alloc (int size);
  27
  28 /*
  29 ================
  30 ResampleSfx
  31 ================
  32 */
  33 void ResampleSfx (sfx_t *sfx, int inrate, int inwidth, byte *data)
  34 {
  35         int             outcount;
  36         int             srcsample;
  37         float   stepscale;
  38         int             i;
  39         int             sample, samplefrac, fracstep;
  40         sfxcache_t      *sc;
  41
  42         sc = Cache_Check (&sfx->cache);
  43         if (!sc)
  44                 return;
  45
  46         stepscale = (float)inrate / shm->speed; // this is usually 0.5, 1, or 2
  47
  48         outcount = sc->length / stepscale;
  49         sc->length = outcount;
  50         if (sc->loopstart != -1)
  51                 sc->loopstart = sc->loopstart / stepscale;
  52
  53         sc->speed = shm->speed;
  54         if (loadas8bit.value)
  55                 sc->width = 1;
  56         else
  57                 sc->width = inwidth;
  58         sc->stereo = 0;
  59
  60 // resample / decimate to the current source rate
  61
  62         if (stepscale == 1 && inwidth == 1 && sc->width == 1)
  63         {
  64 // fast special case
  65                 for (i=0 ; i<outcount ; i++)
  66                         ((signed char *)sc->data)[i]
  67                         = (int)( (unsigned char)(data[i]) - 128);
  68         }
  69         else
  70         {
  71 // general case
  72                 samplefrac = 0;
  73                 fracstep = stepscale*256;
  74                 for (i=0 ; i<outcount ; i++)
  75                 {
  76                         srcsample = samplefrac >> 8;
  77                         samplefrac += fracstep;
  78                         if (inwidth == 2)
  79                                 sample = LittleShort ( ((short *)data)[srcsample] );
  80                         else
  81                                 sample = (int)( (unsigned char)(data[srcsample]) - 128) << 8;
  82                         if (sc->width == 2)
  83                                 ((short *)sc->data)[i] = sample;
  84                         else
  85                                 ((signed char *)sc->data)[i] = sample >> 8;
  86                 }
  87         }
  88 }
  89
  90 //=============================================================================
  91
  92 /*
  93 ==============
  94 S_LoadSound
  95 ==============
  96 */
  97 sfxcache_t *S_LoadSound (sfx_t *s)
  98 {
  99     char        namebuffer[256];
 100         byte    *data;
 101         wavinfo_t       info;
 102         int             len;
 103         float   stepscale;
 104         sfxcache_t      *sc;
 105         byte    stackbuf[1*1024];               // avoid dirtying the cache heap
 106
 107 // see if still in memory
 108         sc = Cache_Check (&s->cache);
 109         if (sc)
 110                 return sc;
 111
 112 //Con_Printf ("S_LoadSound: %x\n", (int)stackbuf);
 113 // load it in
 114     Q_strcpy(namebuffer, "sound/");
 115     Q_strcat(namebuffer, s->name);
 116
 117 //      Con_Printf ("loading %s\n",namebuffer);
 118
 119         data = COM_LoadStackFile(namebuffer, stackbuf, sizeof(stackbuf));
 120
 121         if (!data)
 122         {
 123                 Con_Printf ("Couldn't load %s\n", namebuffer);
 124                 return NULL;
 125         }
 126
 127         info = GetWavinfo (s->name, data, com_filesize);
 128         if (info.channels != 1)
 129         {
 130                 Con_Printf ("%s is a stereo sample\n",s->name);
 131                 return NULL;
 132         }
 133
 134         stepscale = (float)info.rate / shm->speed;
 135         len = info.samples / stepscale;
 136
 137         len = len * info.width * info.channels;
 138
 139         sc = Cache_Alloc ( &s->cache, len + sizeof(sfxcache_t), s->name);
 140         if (!sc)
 141                 return NULL;
 142
 143         sc->length = info.samples;
 144         sc->loopstart = info.loopstart;
 145         sc->speed = info.rate;
 146         sc->width = info.width;
 147         sc->stereo = info.channels;
 148
 149         ResampleSfx (s, sc->speed, sc->width, data + info.dataofs);
 150
 151         return sc;
 152 }
 153
 154
 155
 156 /*
 157 ===============================================================================
 158
 159 WAV loading
 160
 161 ===============================================================================
 162 */
 163
 164
 165 byte    *data_p;
 166 byte    *iff_end;
 167 byte    *last_chunk;
 168 byte    *iff_data;
 169 int     iff_chunk_len;
 170
 171
 172 short GetLittleShort(void)
 173 {
 174         short val = 0;
 175         val = *data_p;
 176         val = val + (*(data_p+1)<<8);
 177         data_p += 2;
 178         return val;
 179 }
 180
 181 int GetLittleLong(void)
 182 {
 183         int val = 0;
 184         val = *data_p;
 185         val = val + (*(data_p+1)<<8);
 186         val = val + (*(data_p+2)<<16);
 187         val = val + (*(data_p+3)<<24);
 188         data_p += 4;
 189         return val;
 190 }
 191
 192 void FindNextChunk(char *name)
 193 {
 194         while (1)
 195         {
 196                 data_p=last_chunk;
 197
 198                 if (data_p >= iff_end)
 199                 {       // didn't find the chunk
 200                         data_p = NULL;
 201                         return;
 202                 }
 203
 204                 data_p += 4;
 205                 iff_chunk_len = GetLittleLong();
 206                 if (iff_chunk_len < 0)
 207                 {
 208                         data_p = NULL;
 209                         return;
 210                 }
 211 //              if (iff_chunk_len > 1024*1024)
 212 //                      Sys_Error ("FindNextChunk: %i length is past the 1 meg sanity limit", iff_chunk_len);
 213                 data_p -= 8;
 214                 last_chunk = data_p + 8 + ( (iff_chunk_len + 1) & ~1 );
 215                 if (!Q_strncmp(data_p, name, 4))
 216                         return;
 217         }
 218 }
 219
 220 void FindChunk(char *name)
 221 {
 222         last_chunk = iff_data;
 223         FindNextChunk (name);
 224 }
 225
 226
 227 void DumpChunks(void)
 228 {
 229         char    str[5];
 230
 231         str[4] = 0;
 232         data_p=iff_data;
 233         do
 234         {
 235                 memcpy (str, data_p, 4);
 236                 data_p += 4;
 237                 iff_chunk_len = GetLittleLong();
 238                 Con_Printf ("0x%x : %s (%d)\n", (int)(data_p - 4), str, iff_chunk_len);
 239                 data_p += (iff_chunk_len + 1) & ~1;
 240         } while (data_p < iff_end);
 241 }
 242
 243 /*
 244 ============
 245 GetWavinfo
 246 ============
 247 */
 248 wavinfo_t GetWavinfo (char *name, byte *wav, int wavlength)
 249 {
 250         wavinfo_t       info;
 251         int     i;
 252         int     format;
 253         int             samples;
 254
 255         memset (&info, 0, sizeof(info));
 256
 257         if (!wav)
 258                 return info;
 259
 260         iff_data = wav;
 261         iff_end = wav + wavlength;
 262
 263 // find "RIFF" chunk
 264         FindChunk("RIFF");
 265         if (!(data_p && !Q_strncmp(data_p+8, "WAVE", 4)))
 266         {
 267                 Con_Printf("Missing RIFF/WAVE chunks\n");
 268                 return info;
 269         }
 270
 271 // get "fmt " chunk
 272         iff_data = data_p + 12;
 273 // DumpChunks ();
 274
 275         FindChunk("fmt ");
 276         if (!data_p)
 277         {
 278                 Con_Printf("Missing fmt chunk\n");
 279                 return info;
 280         }
 281         data_p += 8;
 282         format = GetLittleShort();
 283         if (format != 1)
 284         {
 285                 Con_Printf("Microsoft PCM format only\n");
 286                 return info;
 287         }
 288
 289         info.channels = GetLittleShort();
 290         info.rate = GetLittleLong();
 291         data_p += 4+2;
 292         info.width = GetLittleShort() / 8;
 293
 294 // get cue chunk
 295         FindChunk("cue ");
 296         if (data_p)
 297         {
 298                 data_p += 32;
 299                 info.loopstart = GetLittleLong();
 300 //              Con_Printf("loopstart=%d\n", sfx->loopstart);
 301
 302         // if the next chunk is a LIST chunk, look for a cue length marker
 303                 FindNextChunk ("LIST");
 304                 if (data_p)
 305                 {
 306                         if (!strncmp (data_p + 28, "mark", 4))
 307                         {       // this is not a proper parse, but it works with cooledit...
 308                                 data_p += 24;
 309                                 i = GetLittleLong ();   // samples in loop
 310                                 info.samples = info.loopstart + i;
 311 //                              Con_Printf("looped length: %i\n", i);
 312                         }
 313                 }
 314         }
 315         else
 316                 info.loopstart = -1;
 317
 318 // find data chunk
 319         FindChunk("data");
 320         if (!data_p)
 321         {
 322                 Con_Printf("Missing data chunk\n");
 323                 return info;
 324         }
 325
 326         data_p += 4;
 327         samples = GetLittleLong () / info.width;
 328
 329         if (info.samples)
 330         {
 331                 if (samples < info.samples)
 332                         Sys_Error ("Sound %s has a bad loop length", name);
 333         }
 334         else
 335                 info.samples = samples;
 336
 337         info.dataofs = data_p - wav;
 338
 339         return info;
 340 }
 341