Alc/effects/chorus.c

   1 /**
   2  * OpenAL cross platform audio library
   3  * Copyright (C) 2013 by Mike Gorchak
   4  * This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Library General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  *  License along with this library; if not, write to the
  16  *  Free Software Foundation, Inc.,
  17  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  * Or go to http://www.gnu.org/copyleft/lgpl.html
  19  */
  20
  21 #include "config.h"
  22
  23 #include <math.h>
  24 #include <stdlib.h>
  25
  26 #include "alMain.h"
  27 #include "alFilter.h"
  28 #include "alAuxEffectSlot.h"
  29 #include "alError.h"
  30 #include "alu.h"
  31
  32
  33 enum ChorusWaveForm {
  34     CWF_Triangle = AL_CHORUS_WAVEFORM_TRIANGLE,
  35     CWF_Sinusoid = AL_CHORUS_WAVEFORM_SINUSOID
  36 };
  37
  38 typedef struct ALchorusState {
  39     DERIVE_FROM_TYPE(ALeffectState);
  40
  41     ALfloat *SampleBuffer[2];
  42     ALuint BufferLength;
  43     ALuint offset;
  44     ALuint lfo_range;
  45     ALfloat lfo_scale;
  46     ALint lfo_disp;
  47
  48     /* Gains for left and right sides */
  49     ALfloat Gain[2][MAX_OUTPUT_CHANNELS];
  50
  51     /* effect parameters */
  52     enum ChorusWaveForm waveform;
  53     ALint delay;
  54     ALfloat depth;
  55     ALfloat feedback;
  56 } ALchorusState;
  57
  58 static ALvoid ALchorusState_Destruct(ALchorusState *state)
  59 {
  60     free(state->SampleBuffer[0]);
  61     state->SampleBuffer[0] = NULL;
  62     state->SampleBuffer[1] = NULL;
  63 }
  64
  65 static ALboolean ALchorusState_deviceUpdate(ALchorusState *state, ALCdevice *Device)
  66 {
  67     ALuint maxlen;
  68     ALuint it;
  69
  70     maxlen = fastf2u(AL_CHORUS_MAX_DELAY * 3.0f * Device->Frequency) + 1;
  71     maxlen = NextPowerOf2(maxlen);
  72
  73     if(maxlen != state->BufferLength)
  74     {
  75         void *temp;
  76
  77         temp = realloc(state->SampleBuffer[0], maxlen * sizeof(ALfloat) * 2);
  78         if(!temp) return AL_FALSE;
  79         state->SampleBuffer[0] = temp;
  80         state->SampleBuffer[1] = state->SampleBuffer[0] + maxlen;
  81
  82         state->BufferLength = maxlen;
  83     }
  84
  85     for(it = 0;it < state->BufferLength;it++)
  86     {
  87         state->SampleBuffer[0][it] = 0.0f;
  88         state->SampleBuffer[1][it] = 0.0f;
  89     }
  90
  91     return AL_TRUE;
  92 }
  93
  94 static ALvoid ALchorusState_update(ALchorusState *state, const ALCdevice *Device, const ALeffectslot *Slot)
  95 {
  96     ALfloat frequency = (ALfloat)Device->Frequency;
  97     ALfloat coeffs[MAX_AMBI_COEFFS];
  98     ALfloat rate;
  99     ALint phase;
 100
 101     switch(Slot->EffectProps.Chorus.Waveform)
 102     {
 103         case AL_CHORUS_WAVEFORM_TRIANGLE:
 104             state->waveform = CWF_Triangle;
 105             break;
 106         case AL_CHORUS_WAVEFORM_SINUSOID:
 107             state->waveform = CWF_Sinusoid;
 108             break;
 109     }
 110     state->depth = Slot->EffectProps.Chorus.Depth;
 111     state->feedback = Slot->EffectProps.Chorus.Feedback;
 112     state->delay = fastf2i(Slot->EffectProps.Chorus.Delay * frequency);
 113
 114     /* Gains for left and right sides */
 115     CalcXYZCoeffs(-1.0f, 0.0f, 0.0f, coeffs);
 116     ComputePanningGains(Device->Dry.AmbiCoeffs, Device->Dry.NumChannels, coeffs, Slot->Gain, state->Gain[0]);
 117     CalcXYZCoeffs( 1.0f, 0.0f, 0.0f, coeffs);
 118     ComputePanningGains(Device->Dry.AmbiCoeffs, Device->Dry.NumChannels, coeffs, Slot->Gain, state->Gain[1]);
 119
 120     phase = Slot->EffectProps.Chorus.Phase;
 121     rate = Slot->EffectProps.Chorus.Rate;
 122     if(!(rate > 0.0f))
 123     {
 124         state->lfo_scale = 0.0f;
 125         state->lfo_range = 1;
 126         state->lfo_disp = 0;
 127     }
 128     else
 129     {
 130         /* Calculate LFO coefficient */
 131         state->lfo_range = fastf2u(frequency/rate + 0.5f);
 132         switch(state->waveform)
 133         {
 134             case CWF_Triangle:
 135                 state->lfo_scale = 4.0f / state->lfo_range;
 136                 break;
 137             case CWF_Sinusoid:
 138                 state->lfo_scale = F_TAU / state->lfo_range;
 139                 break;
 140         }
 141
 142         /* Calculate lfo phase displacement */
 143         state->lfo_disp = fastf2i(state->lfo_range * (phase/360.0f));
 144     }
 145 }
 146
 147 static inline void Triangle(ALint *delay_left, ALint *delay_right, ALuint offset, const ALchorusState *state)
 148 {
 149     ALfloat lfo_value;
 150
 151     lfo_value = 2.0f - fabsf(2.0f - state->lfo_scale*(offset%state->lfo_range));
 152     lfo_value *= state->depth * state->delay;
 153     *delay_left = fastf2i(lfo_value) + state->delay;
 154
 155     offset += state->lfo_disp;
 156     lfo_value = 2.0f - fabsf(2.0f - state->lfo_scale*(offset%state->lfo_range));
 157     lfo_value *= state->depth * state->delay;
 158     *delay_right = fastf2i(lfo_value) + state->delay;
 159 }
 160
 161 static inline void Sinusoid(ALint *delay_left, ALint *delay_right, ALuint offset, const ALchorusState *state)
 162 {
 163     ALfloat lfo_value;
 164
 165     lfo_value = 1.0f + sinf(state->lfo_scale*(offset%state->lfo_range));
 166     lfo_value *= state->depth * state->delay;
 167     *delay_left = fastf2i(lfo_value) + state->delay;
 168
 169     offset += state->lfo_disp;
 170     lfo_value = 1.0f + sinf(state->lfo_scale*(offset%state->lfo_range));
 171     lfo_value *= state->depth * state->delay;
 172     *delay_right = fastf2i(lfo_value) + state->delay;
 173 }
 174
 175 #define DECL_TEMPLATE(Func)                                                   \
 176 static void Process##Func(ALchorusState *state, const ALuint SamplesToDo,     \
 177   const ALfloat *restrict SamplesIn, ALfloat (*restrict out)[2])              \
 178 {                                                                             \
 179     const ALuint bufmask = state->BufferLength-1;                             \
 180     ALfloat *restrict leftbuf = state->SampleBuffer[0];                       \
 181     ALfloat *restrict rightbuf = state->SampleBuffer[1];                      \
 182     ALuint offset = state->offset;                                            \
 183     const ALfloat feedback = state->feedback;                                 \
 184     ALuint it;                                                                \
 185                                                                               \
 186     for(it = 0;it < SamplesToDo;it++)                                         \
 187     {                                                                         \
 188         ALint delay_left, delay_right;                                        \
 189         Func(&delay_left, &delay_right, offset, state);                       \
 190                                                                               \
 191         out[it][0] = leftbuf[(offset-delay_left)&bufmask];                    \
 192         leftbuf[offset&bufmask] = (out[it][0]+SamplesIn[it]) * feedback;      \
 193                                                                               \
 194         out[it][1] = rightbuf[(offset-delay_right)&bufmask];                  \
 195         rightbuf[offset&bufmask] = (out[it][1]+SamplesIn[it]) * feedback;     \
 196                                                                               \
 197         offset++;                                                             \
 198     }                                                                         \
 199     state->offset = offset;                                                   \
 200 }
 201
 202 DECL_TEMPLATE(Triangle)
 203 DECL_TEMPLATE(Sinusoid)
 204
 205 #undef DECL_TEMPLATE
 206
 207 static ALvoid ALchorusState_process(ALchorusState *state, ALuint SamplesToDo, const ALfloat (*restrict SamplesIn)[BUFFERSIZE], ALfloat (*restrict SamplesOut)[BUFFERSIZE], ALuint NumChannels)
 208 {
 209     ALuint it, kt;
 210     ALuint base;
 211
 212     for(base = 0;base < SamplesToDo;)
 213     {
 214         ALfloat temps[128][2];
 215         ALuint td = minu(128, SamplesToDo-base);
 216
 217         switch(state->waveform)
 218         {
 219             case CWF_Triangle:
 220                 ProcessTriangle(state, td, SamplesIn[0]+base, temps);
 221                 break;
 222             case CWF_Sinusoid:
 223                 ProcessSinusoid(state, td, SamplesIn[0]+base, temps);
 224                 break;
 225         }
 226
 227         for(kt = 0;kt < NumChannels;kt++)
 228         {
 229             ALfloat gain = state->Gain[0][kt];
 230             if(fabsf(gain) > GAIN_SILENCE_THRESHOLD)
 231             {
 232                 for(it = 0;it < td;it++)
 233                     SamplesOut[kt][it+base] += temps[it][0] * gain;
 234             }
 235
 236             gain = state->Gain[1][kt];
 237             if(fabsf(gain) > GAIN_SILENCE_THRESHOLD)
 238             {
 239                 for(it = 0;it < td;it++)
 240                     SamplesOut[kt][it+base] += temps[it][1] * gain;
 241             }
 242         }
 243
 244         base += td;
 245     }
 246 }
 247
 248 DECLARE_DEFAULT_ALLOCATORS(ALchorusState)
 249
 250 DEFINE_ALEFFECTSTATE_VTABLE(ALchorusState);
 251
 252
 253 typedef struct ALchorusStateFactory {
 254     DERIVE_FROM_TYPE(ALeffectStateFactory);
 255 } ALchorusStateFactory;
 256
 257 static ALeffectState *ALchorusStateFactory_create(ALchorusStateFactory *UNUSED(factory))
 258 {
 259     ALchorusState *state;
 260
 261     state = ALchorusState_New(sizeof(*state));
 262     if(!state) return NULL;
 263     SET_VTABLE2(ALchorusState, ALeffectState, state);
 264
 265     state->BufferLength = 0;
 266     state->SampleBuffer[0] = NULL;
 267     state->SampleBuffer[1] = NULL;
 268     state->offset = 0;
 269     state->lfo_range = 1;
 270     state->waveform = CWF_Triangle;
 271
 272     return STATIC_CAST(ALeffectState, state);
 273 }
 274
 275 DEFINE_ALEFFECTSTATEFACTORY_VTABLE(ALchorusStateFactory);
 276
 277
 278 ALeffectStateFactory *ALchorusStateFactory_getFactory(void)
 279 {
 280     static ALchorusStateFactory ChorusFactory = { { GET_VTABLE2(ALchorusStateFactory, ALeffectStateFactory) } };
 281
 282     return STATIC_CAST(ALeffectStateFactory, &ChorusFactory);
 283 }
 284
 285
 286 void ALchorus_setParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val)
 287 {
 288     ALeffectProps *props = &effect->Props;
 289     switch(param)
 290     {
 291         case AL_CHORUS_WAVEFORM:
 292             if(!(val >= AL_CHORUS_MIN_WAVEFORM && val <= AL_CHORUS_MAX_WAVEFORM))
 293                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 294             props->Chorus.Waveform = val;
 295             break;
 296
 297         case AL_CHORUS_PHASE:
 298             if(!(val >= AL_CHORUS_MIN_PHASE && val <= AL_CHORUS_MAX_PHASE))
 299                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 300             props->Chorus.Phase = val;
 301             break;
 302
 303         default:
 304             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 305     }
 306 }
 307 void ALchorus_setParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals)
 308 {
 309     ALchorus_setParami(effect, context, param, vals[0]);
 310 }
 311 void ALchorus_setParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val)
 312 {
 313     ALeffectProps *props = &effect->Props;
 314     switch(param)
 315     {
 316         case AL_CHORUS_RATE:
 317             if(!(val >= AL_CHORUS_MIN_RATE && val <= AL_CHORUS_MAX_RATE))
 318                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 319             props->Chorus.Rate = val;
 320             break;
 321
 322         case AL_CHORUS_DEPTH:
 323             if(!(val >= AL_CHORUS_MIN_DEPTH && val <= AL_CHORUS_MAX_DEPTH))
 324                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 325             props->Chorus.Depth = val;
 326             break;
 327
 328         case AL_CHORUS_FEEDBACK:
 329             if(!(val >= AL_CHORUS_MIN_FEEDBACK && val <= AL_CHORUS_MAX_FEEDBACK))
 330                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 331             props->Chorus.Feedback = val;
 332             break;
 333
 334         case AL_CHORUS_DELAY:
 335             if(!(val >= AL_CHORUS_MIN_DELAY && val <= AL_CHORUS_MAX_DELAY))
 336                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 337             props->Chorus.Delay = val;
 338             break;
 339
 340         default:
 341             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 342     }
 343 }
 344 void ALchorus_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals)
 345 {
 346     ALchorus_setParamf(effect, context, param, vals[0]);
 347 }
 348
 349 void ALchorus_getParami(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *val)
 350 {
 351     const ALeffectProps *props = &effect->Props;
 352     switch(param)
 353     {
 354         case AL_CHORUS_WAVEFORM:
 355             *val = props->Chorus.Waveform;
 356             break;
 357
 358         case AL_CHORUS_PHASE:
 359             *val = props->Chorus.Phase;
 360             break;
 361
 362         default:
 363             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 364     }
 365 }
 366 void ALchorus_getParamiv(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals)
 367 {
 368     ALchorus_getParami(effect, context, param, vals);
 369 }
 370 void ALchorus_getParamf(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val)
 371 {
 372     const ALeffectProps *props = &effect->Props;
 373     switch(param)
 374     {
 375         case AL_CHORUS_RATE:
 376             *val = props->Chorus.Rate;
 377             break;
 378
 379         case AL_CHORUS_DEPTH:
 380             *val = props->Chorus.Depth;
 381             break;
 382
 383         case AL_CHORUS_FEEDBACK:
 384             *val = props->Chorus.Feedback;
 385             break;
 386
 387         case AL_CHORUS_DELAY:
 388             *val = props->Chorus.Delay;
 389             break;
 390
 391         default:
 392             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 393     }
 394 }
 395 void ALchorus_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals)
 396 {
 397     ALchorus_getParamf(effect, context, param, vals);
 398 }
 399
 400 DEFINE_ALEFFECT_VTABLE(ALchorus);