effects.c

   1 #include "effects.h"
   2 #include "effect.h"
   3 #include "math.h"
   4 #include "stdlib.h"
   5
   6 struct silly_effect {
   7     struct effect e;
   8 };
   9
  10 int silly_effect_process(struct effect *ef, void **buf, long n_samples)
  11 {
  12     short *bufp;
  13     int i;
  14
  15     if (!*buf){
  16         // we're not a source
  17         return 1;
  18     }
  19
  20     bufp = *buf;
  21     for (i = 0; i < n_samples; ++i){
  22         bufp[i * 2] *= cos((i * 2 * M_PI) / 441.0);
  23         bufp[i * 2 + 1] *= cos((i * 2 * M_PI) / 441.0);
  24     }
  25     return 0;
  26 }
  27
  28 static const struct effect_vtab silly_effect_vtab = {
  29     process: silly_effect_process,
  30 };
  31
  32 struct effect *silly_effect_create(void)
  33 {
  34     struct silly_effect *se;
  35     se = malloc(sizeof *se);
  36     if (!se){
  37         return NULL;
  38     }
  39     se->e.vtab = &silly_effect_vtab;
  40     return &se->e;
  41 }
  42
  43 void silly_effect_free(struct effect *e)
  44 {
  45     free(e);
  46 }