org.c

   1 /*
   2 org.c
   3 various software synths and samples
   4
   5 Copyright (C) 2009 Evan Rinehart
   6
   7 This software comes with no warranty.
   8 1. This software can be used for any purpose, good or evil.
   9 2. Modifications must retain this license, at least in spirit.
  10 */
  11
  12 #include <stdlib.h>
  13 #include <math.h>
  14
  15 #include <audio.h> /* to have SAMPLE_RATE */
  16 #include <org.h>
  17
  18
  19 instrument make_cool() {
  20         instrument ins;
  21         ins.mix = NULL;
  22         ins.control = NULL;
  23         ins.cleanup = NULL;
  24         ins.data = NULL;
  25         return ins;
  26 }
  27
  28 float note2f(int note){
  29         return 440*3.14159*2*pow(2, note/12.0)/SAMPLE_RATE;
  30 }
  31
  32 struct foo {
  33         int on;
  34         float t;
  35         float f;
  36 };
  37
  38 void foo_mix(void* data, float out[], int count){
  39         struct foo* foo = data;
  40         int i;
  41
  42         if(foo->on == 0) return;
  43
  44         for(i=0; i<count; i++){
  45                 out[i] += sin(foo->t);
  46                 foo->t += foo->f;
  47                 while(foo->t > 2*3.14159){
  48                         foo->t -= 2*3.14159;
  49                 }
  50         }
  51 }
  52
  53 void foo_control(void* data, int type, int val1, int val2, int val){
  54         struct foo* foo = data;
  55         switch(type){
  56                 case 0: foo->on = 1; break;
  57                 case 2: foo->on = 0; break;
  58                 case 1: foo->f = note2f(val1); break;
  59         }
  60 }
  61
  62 void foo_cleanup(void* data){ free(data); }
  63
  64 instrument make_foo(){
  65         instrument ins;
  66         ins.mix = foo_mix;
  67         ins.control = foo_control;
  68         ins.cleanup = foo_cleanup;
  69         ins.data = malloc(sizeof(struct foo));
  70         return ins;
  71 }
  72
  73 instrument load_instrument(enum instrument_name name){
  74         switch(name){
  75                 case ORG_FOO: return make_foo();
  76                 case ORG_COOL: return make_cool();
  77                 default: return make_foo();
  78         }
  79 }