sound.c

   1 #include "glob.h"
   2 #include "files.h"
   3 #include "sound.h"
   4 #include <SDL.h>
   5 #include <SDL_mixer.h>
   6
   7 #define NUM_CHANNELS 16
   8 #define NUM_CHUNKS 300
   9
  10 short snd_vol = 50;
  11
  12 int snddisabled = 1;
  13
  14 struct {
  15     snd_t *s;
  16     Mix_Chunk *c;
  17 } chunks[NUM_CHUNKS];
  18
  19 void S_init(void)
  20 {
  21     if (!SDL_WasInit(SDL_INIT_AUDIO)) {
  22         if (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0) {
  23             fprintf(stderr, "\nUnable to initialize audio:  %s\n", SDL_GetError());
  24             snddisabled=1;
  25             return;
  26         }
  27
  28         if (Mix_OpenAudio(22050, AUDIO_S16, 1, 1000) < 0) {
  29             fprintf(stderr, "Error initializing SDL_mixer: %s\n", Mix_GetError());
  30             snddisabled=1;
  31             return;
  32         }
  33
  34         if (Mix_AllocateChannels(NUM_CHANNELS)!=NUM_CHANNELS) {
  35             fprintf(stderr, "Error allocation channels: %s\n", Mix_GetError());
  36             snddisabled=1;
  37             return;
  38         }
  39     }
  40
  41     int i;
  42     for (i=0; i<NUM_CHUNKS; i++) {
  43         chunks[i].s = NULL;
  44         chunks[i].c = NULL;
  45     }
  46
  47     snddisabled = (snd_vol==0);
  48
  49    S_volume(snd_vol);
  50 }
  51
  52 void S_done(void)
  53 {
  54     free_chunks();
  55     Mix_CloseAudio();
  56     SDL_QuitSubSystem(SDL_INIT_AUDIO);
  57 }
  58
  59 Mix_Chunk * get_chunk(snd_t *s, int r, int v)
  60 {
  61     int i, fi = -1;
  62     for(i=0; i<NUM_CHUNKS; i++) {
  63         if (chunks[i].s == s) return chunks[i].c;
  64         if (chunks[i].s == NULL && fi==-1) fi = i;
  65     }
  66
  67     if (fi==-1) return NULL;
  68
  69   Uint8 *data = (Uint8*)s+sizeof(snd_t);
  70   Uint32 dlen = s->len;
  71   SDL_AudioCVT cvt;
  72   SDL_BuildAudioCVT(&cvt, AUDIO_S8, 1, s->rate, AUDIO_S16, 1, 22050);
  73   if (!(cvt.buf = malloc(dlen*cvt.len_mult))) ERR_fatal("Out of memory\n");;
  74   memcpy(cvt.buf, data, dlen);
  75   cvt.len = dlen;
  76   SDL_ConvertAudio(&cvt);
  77
  78     Mix_Chunk *chunk;
  79     if (!(chunk = malloc(sizeof(Mix_Chunk)))) ERR_fatal("Out of memory\n");;
  80     chunk->abuf=cvt.buf;
  81     chunk->alen=cvt.len_cvt;
  82     chunk->allocated=0;
  83     chunk->volume=(float)v/255*SDL_MIX_MAXVOLUME;
  84
  85     chunks[fi].s = s;
  86     chunks[fi].c = chunk;
  87
  88     return chunk;
  89 }
  90
  91 void free_chunks()
  92 {
  93     if (snddisabled) return;
  94     Mix_HaltChannel(-1);
  95     int i;
  96     for (i=0; i<NUM_CHUNKS; i++) {
  97         if (chunks[i].c) {
  98             free(chunks[i].c->abuf);
  99             free(chunks[i].c);
 100             chunks[i].c = NULL;
 101             chunks[i].s = NULL;
 102         }
 103     }
 104 }
 105
 106 short S_play(snd_t *s,short c,unsigned r,short v)
 107 {
 108     if (snddisabled) return 0;
 109     Mix_Chunk *chunk = get_chunk(s,r,v);
 110     if (chunk==NULL) return 0;
 111     return Mix_PlayChannel(c, chunk, 0);
 112 }
 113
 114 void S_stop(short c)
 115 {
 116     Mix_HaltChannel(c);
 117 }
 118
 119 void S_volume(int v)
 120 {
 121     if (snddisabled) return;
 122     snd_vol=v;
 123     if (snd_vol>128) snd_vol=128;
 124     if (snd_vol<0) snd_vol=0;
 125     Mix_Volume(-1, snd_vol);
 126 }
 127
 128 void S_wait()
 129 {
 130     if (snddisabled) return;
 131     while (Mix_Playing(-1)) {
 132         SDL_Delay(10);
 133     }
 134 }