vg_audio_synth_bird.h

   1 #ifndef VG_AUDIO_SYNTH_BIRD_H
   2 #define VG_AUDIO_SYNTH_BIRD_H
   3
   4 #include "vg_binstr.h"
   5 #include "vg_stdint.h"
   6
   7 #ifndef BIRD_SAMPLE_RATE
   8  #define BIRD_SAMPLE_RATE 44100
   9 #endif
  10
  11 struct synth_bird_signature
  12 {
  13    float length, pause,  /* timings in seconds */
  14          x0,x1,x2,x3,    /* polynomial coefficients for the fundemental */
  15          v0,v1,v2,v3;    /* volume of each oscillator */
  16
  17    int   lfo_hz;         /* LFO frequency (30-60hz) */
  18    float fm;             /* LFO modulation depth (+/- hz) */
  19 };
  20
  21 struct synth_bird
  22 {
  23    struct
  24    {
  25       int osc_main[4],
  26           osc_lfo;
  27       float volume[4];
  28
  29       float fundamental;
  30       int x, length,       /* position/length of signature in samples */
  31           gate, adsr,      /* adsr ranges 0->44100 */
  32           frame;           /* current frame of the pattern */
  33
  34       int   lfo_hz;
  35       float fm_depth;
  36
  37       int adsr_rise,
  38           adsr_fall;
  39    }
  40    rt;
  41
  42    struct synth_bird_settings
  43    {
  44       int tones[4][2];        /* fraction of the fundemental tone
  45                                  for each oscillator */
  46       float adsr_rise,        /* rise/fall in seconds */
  47             adsr_fall;
  48
  49       enum bird_lfo_wave
  50       {
  51          k_bird_lfo_sine_approx,
  52          k_bird_lfo_bipolar_poly
  53       }
  54       type;
  55
  56       int pattern_length;
  57       struct synth_bird_signature pattern[];
  58    }
  59    settings;
  60 };
  61
  62 #define DEFAULT_VOL 1.0f,0.5f,0.2f,0.125f
  63 #define DEFAULT_TONES { {1,1}, {6,5}, {8,7}, {13,12} }
  64 #define DEFAULT_RISE 0.00090702947f
  65 #define DEFAULT_FALL 0.00226757369f
  66
  67 static struct synth_bird_settings synth_bird__default_settings =
  68 {
  69    .tones = DEFAULT_TONES,
  70    .type  = k_bird_lfo_sine_approx,
  71    .adsr_rise = DEFAULT_RISE,
  72    .adsr_fall = DEFAULT_FALL
  73 };
  74
  75 static struct synth_bird_signature synth_bird__warbling_vireo[] =
  76 {
  77    /* timing    fundemental            volumes       lfo hz,depth */
  78    {0.13,0.10,  4000,100,100,0,        DEFAULT_VOL,  60,200 },
  79    {0.10,0.05,  4200,-500,1700,0,      DEFAULT_VOL,  60,96  },
  80    {0.10,0.00,  2400,-1200,1000,1700,  DEFAULT_VOL,  60,96  },
  81    {0.06,0.04,  3100,200,-10,-1100,    DEFAULT_VOL,  60,90  },
  82    {0.13,0.07,  4600,-2000,0,1300,     DEFAULT_VOL,  60,10  },
  83    {0.05,0.00,  2700,-300,700,800,     DEFAULT_VOL,  60,10  },
  84    {0.09,0.07,  3600,-300,0,0,         DEFAULT_VOL,  60,20  },
  85    {0.05,0.07,  4800,1240,300,0,       DEFAULT_VOL,  60,20  },
  86    {0.08,0.02,  2700,-800,150,1000,    DEFAULT_VOL,  60,160 },
  87    {0.12,0.08,  2700,-800,150,1000,    DEFAULT_VOL,  60,160 },
  88    {0.10,0.04,  6300,-100,-3200,1000,  DEFAULT_VOL,  60,100 },
  89    {0.16,0.10,  4260,-200,300,1100,    DEFAULT_VOL,  60,20  }
  90 };
  91
  92 static struct synth_bird_signature synth_bird__pied_monarch[] =
  93 {
  94    /* timing    fundemental       volumes        lfo hz,depth */
  95    {0.18,0.13,  2200,700,-300,0,  0.6,0.05,0,0,  60,0  },
  96    {0.17,0.12,  2200,700,-300,0,  0.8,0.05,0,0,  60,0  },
  97    {0.16,0.11,  2200,700,-300,0,  0.9,0.05,0,0,  60,0  },
  98    {0.14,0.09,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
  99    {0.12,0.07,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 100    {0.11,0.06,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 101    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 102    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 103    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 104    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 105    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 106    {0.10,0.10,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  }
 107 };
 108
 109 static struct synth_bird_signature synth_bird__bridled_honeyeater[] =
 110 {
 111    /* timing    fundemental        volumes               lfo hz,depth */
 112    {0.10,0.10,  2000,-1000,600,0,  1.00,0.00,0.00,0.00,  30,60},
 113    {0.10,0.10,  4000,0,-200,-200,  0.80,0.25,0.25,0.25,  30,60},
 114    {0.06,0.01,  4000,0,-700,-800,  0.90,0.10,0.00,0.00,  60,20},
 115    {0.07,0.01,  3950,0,-700,-800,  0.90,0.10,0.00,0.00,  60,20},
 116    {0.08,0.01,  3900,0,-700,-800,  0.90,0.10,0.00,0.00,  60,20},
 117    {0.09,0.01,  3850,0,-700,-800,  0.90,0.10,0.00,0.00,  60,20},
 118    {0.10,0.02,  3800,0,-700,-800,  0.90,0.20,0.10,0.00,  60,20},
 119    {0.11,0.05,  3750,0,-700,-800,  0.90,0.40,0.20,0.00,  60,20},
 120    {0.12,0.20,  3700,0,-700,-800,  0.30,0.10,0.00,0.00,  60,20},
 121    {0.10,0.10,  2600,1300,600,0,   0.97,0.03,0.00,0.00,  60,20},
 122 };
 123
 124 static struct synth_bird_signature synth_bird__cricket[] =
 125 {
 126    /* timing   fundemental   volumes              lfo hz, depth */
 127    {0.10,0.15, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 128    {0.11,0.14, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 129    {0.13,0.15, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 130    {0.09,0.16, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 131    {0.10,0.12, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 132    {0.10,0.15, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 133    {0.11,0.14, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 134    {0.13,0.15, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 135    {0.09,0.16, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 136    {0.10,0.12, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200}
 137 };
 138
 139 static struct synth_bird_signature synth_bird__gray_shrikethrush[] =
 140 {
 141    /* timing   fundemental         volumes             lfo hz, depth */
 142    { 0.13,0.1, 2600,-200,-100,200, 0.9,0.1,0.05,0.001, 60,10 }
 143 };
 144
 145 static struct synth_bird_signature synth_bird__boobook[] =
 146 {
 147    /* timing  fundemental     volumes           lfo hz, depth */
 148    {0.3,0.14, 700,0,-100,100, 0.9,0.14,0.0,0.2, 30,18},
 149    {0.3,1.20, 630,0,-100,100, 0.9,0.00,0.3,0.0, 30,18}
 150 };
 151
 152 static struct synth_bird_signature synth_bird__shrike_tit[] =
 153 {
 154    /* timing   fundemental         volumes           lfo hz, depth */
 155    {0.6,1.4,   2300,-300,-100,100, 1.0,0.14,0.0,0.1, 60,5 }
 156 };
 157
 158 /* sine functions over the range [0, 44100] : [-pi, pi].
 159  * Not accurate! */
 160
 161 static float sine_1second_1( int o )
 162 {
 163    float s = (o<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 164    float t = ((float)o*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s*0.5f;
 165    float t2 = t*t;
 166    float t4 = t2*t2;
 167    return s*(5.0f*t2-4.0f*t4-1.0f);
 168 }
 169
 170 static void sine_1second_4( int o[4], float v[4] )
 171 {
 172    float s[4],t[4],t2[4],t4[4];
 173    s[0] = (o[0]<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 174    s[1] = (o[1]<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 175    s[2] = (o[2]<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 176    s[3] = (o[3]<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 177
 178    t[0] = ((float)o[0]*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s[0]*0.5f;
 179    t[1] = ((float)o[1]*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s[1]*0.5f;
 180    t[2] = ((float)o[2]*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s[2]*0.5f;
 181    t[3] = ((float)o[3]*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s[3]*0.5f;
 182
 183    t2[0] = t[0]*t[0];
 184    t2[1] = t[1]*t[1];
 185    t2[2] = t[2]*t[2];
 186    t2[3] = t[3]*t[3];
 187
 188    t4[0] = t2[0]*t2[0];
 189    t4[1] = t2[1]*t2[1];
 190    t4[2] = t2[2]*t2[2];
 191    t4[3] = t2[3]*t2[3];
 192
 193    v[0] = s[0]*(5.0f*t2[0]-4.0f*t4[0]-1.0f);
 194    v[1] = s[1]*(5.0f*t2[1]-4.0f*t4[1]-1.0f);
 195    v[2] = s[2]*(5.0f*t2[2]-4.0f*t4[2]-1.0f);
 196    v[3] = s[3]*(5.0f*t2[3]-4.0f*t4[3]-1.0f);
 197 }
 198
 199 static float saw_1second_1( int o )
 200 {
 201    float t = ((float)o*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f,
 202          tt = t*t,
 203          ttt = tt*t;
 204
 205    return -2.5f*ttt+2.5f*t;
 206 }
 207
 208 static u32 synth_bird_get_length_in_samples( struct synth_bird *bird )
 209 {
 210    u32 total = 0;
 211
 212    for( int i=0; i<bird->settings.pattern_length; i ++ )
 213    {
 214       struct synth_bird_signature *sig = &bird->settings.pattern[i];
 215
 216       u32 l = sig->length * (float)BIRD_SAMPLE_RATE,
 217           p = sig->pause  * (float)BIRD_SAMPLE_RATE;
 218
 219       total += l+p;
 220    }
 221
 222    return total;
 223 }
 224
 225 static void synth_bird_reset( struct synth_bird *bird )
 226 {
 227    bird->rt.osc_main[0] = 0;
 228    bird->rt.osc_main[1] = 0;
 229    bird->rt.osc_main[2] = 0;
 230    bird->rt.osc_main[3] = 0;
 231    bird->rt.osc_lfo = 0;
 232
 233    bird->rt.volume[0] = 0.0f;
 234    bird->rt.volume[1] = 0.0f;
 235    bird->rt.volume[2] = 0.0f;
 236    bird->rt.volume[3] = 0.0f;
 237
 238    bird->rt.fundamental = 0.0f;
 239    bird->rt.x = 0;
 240    bird->rt.length = bird->settings.pattern[0].length * (float)BIRD_SAMPLE_RATE;
 241    bird->rt.gate = 1;
 242    bird->rt.adsr = 0;
 243    bird->rt.frame = 0;
 244    bird->rt.lfo_hz = 0;
 245    bird->rt.fm_depth = 0.0f;
 246
 247    bird->rt.adsr_rise = bird->settings.adsr_rise * (float)BIRD_SAMPLE_RATE;
 248    bird->rt.adsr_fall = bird->settings.adsr_fall * (float)BIRD_SAMPLE_RATE;
 249 }
 250
 251 static u32 synth_bird_save_size( struct synth_bird *bird )
 252 {
 253    return sizeof(struct synth_bird_signature) * bird->settings.pattern_length +
 254           sizeof(struct synth_bird_settings);
 255 }
 256
 257 static void synth_bird_save( struct synth_bird *bird, void *txt )
 258 {
 259    void *src = &bird->settings;
 260    vg_bin_str( src, txt, synth_bird_save_size( bird ) );
 261 }
 262
 263 static void synth_bird_load( struct synth_bird *bird,
 264                              const char *txt, u32 length )
 265 {
 266    vg_str_bin( txt, &bird->settings, length );
 267    synth_bird_reset( bird );
 268 }
 269
 270 /* expects a null terminated string */
 271 static u32 synth_bird_memory_requirement( u32 string_length )
 272 {
 273    return (string_length/2) +
 274             sizeof(struct synth_bird) - sizeof(struct synth_bird_settings);
 275 }
 276
 277 #ifdef SYNTH_BIRD_STDLIB
 278 #include "stdlib.h"
 279 #include "string.h"
 280
 281 static struct synth_bird *synth_bird_create(
 282                            struct synth_bird_settings *settings,
 283                            struct synth_bird_signature *pattern,
 284                            u32 pattern_length )
 285 {
 286    u32 pattern_size = sizeof( struct synth_bird_signature ) * pattern_length;
 287    u32 total_size = sizeof( struct synth_bird ) + pattern_size;
 288    struct synth_bird *bird = malloc( total_size );
 289
 290    bird->settings = *settings;
 291
 292    memcpy( bird->settings.pattern, pattern, pattern_size );
 293    bird->settings.pattern_length = pattern_length;
 294
 295    synth_bird_reset( bird );
 296    return bird;
 297 }
 298
 299 #endif
 300
 301 static void synth_bird_think( struct synth_bird *bird )
 302 {
 303    struct synth_bird_signature *sig = &bird->settings.pattern[ bird->rt.frame ];
 304
 305    bird->rt.x ++;
 306    if( bird->rt.x >= bird->rt.length )
 307    {
 308       if( bird->rt.gate && (sig->pause != 0.0f) )
 309       {
 310          bird->rt.gate = 0;
 311          bird->rt.length = sig->pause * (float)BIRD_SAMPLE_RATE;
 312       }
 313       else
 314       {
 315          bird->rt.frame ++;
 316
 317          if( bird->rt.frame >= bird->settings.pattern_length )
 318             bird->rt.frame = 0;
 319
 320          sig = &bird->settings.pattern[ bird->rt.frame ];
 321
 322          bird->rt.gate = 1;
 323          bird->rt.length = sig->length * (float)BIRD_SAMPLE_RATE;
 324       }
 325
 326       bird->rt.x = 0;
 327    }
 328
 329    if( bird->rt.gate )
 330    {
 331       bird->rt.adsr += bird->rt.adsr_rise;
 332       if( bird->rt.adsr > BIRD_SAMPLE_RATE )
 333          bird->rt.adsr = BIRD_SAMPLE_RATE;
 334    }
 335    else
 336    {
 337       bird->rt.adsr -= bird->rt.adsr_fall;
 338       if( bird->rt.adsr < 0 )
 339          bird->rt.adsr = 0;
 340    }
 341
 342    if( bird->rt.gate )
 343    {
 344       float l = (float)bird->rt.length,
 345             t = ((float)bird->rt.x * (1.0f/l))*2.0f - 1.0f,
 346             tt = t*t,
 347             ttt = tt*t;
 348
 349       bird->rt.fundamental = sig->x0 + t*sig->x1 + tt*sig->x2 + ttt*sig->x3;
 350    }
 351
 352    float vol = (float)bird->rt.adsr * (1.0f/(float)BIRD_SAMPLE_RATE);
 353
 354    bird->rt.fm_depth  = sig->fm;
 355    bird->rt.lfo_hz    = sig->lfo_hz;
 356    bird->rt.volume[0] = sig->v0 * vol;
 357    bird->rt.volume[1] = sig->v1 * vol;
 358    bird->rt.volume[2] = sig->v2 * vol;
 359    bird->rt.volume[3] = sig->v3 * vol;
 360 }
 361
 362 static inline void int_add_mod( int *a, int const b )
 363 {
 364    *a += b;
 365
 366    if( *a > BIRD_SAMPLE_RATE )
 367       *a -= BIRD_SAMPLE_RATE;
 368 }
 369
 370 static void synth_bird_generate_samples( struct synth_bird *bird,
 371                                         float *stereo_buffer, int samples )
 372 {
 373    for( int _=0; _<samples; _++ )
 374    {
 375       synth_bird_think( bird );
 376
 377       int_add_mod( &bird->rt.osc_lfo, bird->rt.lfo_hz );
 378       float fm = sine_1second_1( bird->rt.osc_lfo ) * bird->rt.fm_depth;
 379
 380       int freq = bird->rt.fundamental + fm;
 381       int hz[4] =
 382       {
 383          (freq * bird->settings.tones[0][0]) / bird->settings.tones[0][1],
 384          (freq * bird->settings.tones[1][0]) / bird->settings.tones[1][1],
 385          (freq * bird->settings.tones[2][0]) / bird->settings.tones[2][1],
 386          (freq * bird->settings.tones[3][0]) / bird->settings.tones[3][1],
 387       };
 388
 389       int_add_mod( bird->rt.osc_main + 0, hz[0] );
 390       int_add_mod( bird->rt.osc_main + 1, hz[1] );
 391       int_add_mod( bird->rt.osc_main + 2, hz[2] );
 392       int_add_mod( bird->rt.osc_main + 3, hz[3] );
 393
 394       float v[4];
 395       sine_1second_4( bird->rt.osc_main, v );
 396
 397       float s = v[0] * bird->rt.volume[0] +
 398                 v[1] * bird->rt.volume[1] +
 399                 v[2] * bird->rt.volume[2] +
 400                 v[3] * bird->rt.volume[3] ;
 401
 402       stereo_buffer[ _*2+0 ] = s;
 403       stereo_buffer[ _*2+1 ] = s;
 404    }
 405 }
 406
 407 #ifdef SYNTH_BIRD_STDLIB
 408 #include "stdio.h"
 409
 410 #define KNRM  "\x1B[00m"
 411 #define KRED  "\x1B[31m"
 412 #define KGRN  "\x1B[32m"
 413 #define KYEL  "\x1B[33m"
 414 #define KBLU  "\x1B[34m"
 415 #define KMAG  "\x1B[35m"
 416 #define KCYN  "\x1B[36m"
 417 #define KWHT  "\x1B[37m"
 418
 419 #define LOG_BAR0 "               .               |"
 420 #define LOG_BAR1 "-------+-------+-------+-------+"
 421 #define LOG_BAR2     "                            "
 422
 423 static void synth_bird_log_pattern( struct synth_bird *bird )
 424 {
 425    synth_bird_reset( bird );
 426
 427    char output[][400]= {
 428 KNRM "9k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 429 KNRM "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 430 KNRM "8k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 431 KNRM "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 432 KNRM "7k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 433 KNRM "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 434 KMAG "6k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 435 KMAG "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 436 KCYN "5k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 437 KCYN "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 438 KBLU "4k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 439 KBLU "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 440 KGRN "3k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 441 KGRN "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 442 KYEL "2k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 443 KYEL "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 444 KRED "1k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 445 KRED "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 446 KWHT "  +"   LOG_BAR1      LOG_BAR1      LOG_BAR1      LOG_BAR1      LOG_BAR1
 447 KWHT "  0.0s"LOG_BAR2"0.5s"LOG_BAR2"1.0s"LOG_BAR2"1.5s"LOG_BAR2"2.0s"LOG_BAR2
 448    };
 449
 450    for( int i=0; i<190*8; i++ )
 451    {
 452       for( int j=0; j<BIRD_SAMPLE_RATE/(32*8*2); j++ )
 453          synth_bird_think( bird );
 454
 455       float hz = bird->rt.fundamental / 500.0f;
 456       int j = hz;
 457
 458       if( j < 0 ) j = 0;
 459       if( j > 18 ) j = 18;
 460       j = 18-j;
 461
 462       float level = bird->rt.adsr;
 463             level *= (1.0f/(float)BIRD_SAMPLE_RATE);
 464
 465       int ch = level*3.0f;
 466
 467       if( ch )
 468          output[j][(i/8)+7] = " *###"[ch];
 469    }
 470
 471    for( int i=0; i<20; i++ )
 472    {
 473       puts( output[i] );
 474    }
 475 }
 476 #endif
 477
 478 #endif /* VG_AUDIO_SYNTH_BIRD_H */