src/sound_medium.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <assert.h>
   4
   5 #include <SDL2/SDL.h>
   6 #include <SDL2/SDL_mixer.h>
   7
   8 #include "./sound_medium.h"
   9 #include "./lt.h"
  10 #include "./error.h"
  11 #include "./pi.h"
  12 #include "./algo.h"
  13
  14 struct sound_medium_t
  15 {
  16     lt_t *lt;
  17     Mix_Chunk **samples;
  18     size_t samples_count;
  19     int paused;
  20     int lower_channel;
  21     int upper_channel;
  22     size_t channels_count;
  23 };
  24
  25 static int mix_get_free_channel(int lower_channel,
  26                                 int upper_channel)
  27 {
  28     assert(lower_channel >= 0);
  29     assert(upper_channel >= 0);
  30     assert(lower_channel <= upper_channel);
  31
  32     for (int i = lower_channel; i < upper_channel; ++i) {
  33         if (!Mix_Playing(i)) {
  34             return i;
  35         }
  36     }
  37
  38     return -1;
  39 }
  40
  41 sound_medium_t *create_sound_medium(Mix_Chunk **samples,
  42                                     size_t samples_count,
  43                                     int lower_channel,
  44                                     int upper_channel)
  45 {
  46     assert(samples);
  47     assert(samples_count > 0);
  48     assert(lower_channel >= 0);
  49     assert(upper_channel >= 0);
  50     assert(lower_channel <= upper_channel);
  51
  52     lt_t *lt = create_lt();
  53     if (lt == NULL) {
  54         return NULL;
  55     }
  56
  57     sound_medium_t *sound_medium = PUSH_LT(lt, malloc(sizeof(sound_medium_t)), free);
  58     if (sound_medium == NULL) {
  59         throw_error(ERROR_TYPE_LIBC);
  60         RETURN_LT(lt, NULL);
  61     }
  62
  63     sound_medium->channels_count = (size_t) (upper_channel - lower_channel + 1);
  64     sound_medium->samples = samples;
  65     sound_medium->samples_count = samples_count;
  66     sound_medium->paused = 0;
  67     sound_medium->lower_channel = lower_channel;
  68     sound_medium->upper_channel = upper_channel;
  69
  70     sound_medium->lt = lt;
  71
  72     return sound_medium;
  73 }
  74
  75 void destroy_sound_medium(sound_medium_t *sound_medium)
  76 {
  77     assert(sound_medium);
  78     RETURN_LT0(sound_medium->lt);
  79 }
  80
  81 int sound_medium_play_sound(sound_medium_t *sound_medium,
  82                             size_t sound_index,
  83                             point_t position,
  84                             int loops)
  85 {
  86     assert(sound_medium);
  87     (void) sound_index;
  88     (void) position;
  89
  90     if (sound_index < sound_medium->samples_count) {
  91         const int free_channel = mix_get_free_channel(sound_medium->lower_channel,
  92                                                       sound_medium->upper_channel);
  93
  94         printf("Found free channel: %d\n", free_channel);
  95
  96         if (free_channel >= 0) {
  97             return Mix_PlayChannel(free_channel, sound_medium->samples[sound_index], loops);
  98         }
  99     }
 100
 101     return 0;
 102 }
 103
 104 int sound_medium_toggle_pause(sound_medium_t *sound_medium)
 105 {
 106     assert(sound_medium);
 107
 108     if (sound_medium->paused) {
 109         Mix_Resume(-1);
 110     } else {
 111         Mix_Pause(-1);
 112     }
 113
 114     sound_medium->paused = !sound_medium->paused;
 115
 116     return 0;
 117 }