Alc/effects/modulator.c

   1 /**
   2  * OpenAL cross platform audio library
   3  * Copyright (C) 2009 by Chris Robinson.
   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 typedef struct ALmodulatorState {
  34     DERIVE_FROM_TYPE(ALeffectState);
  35
  36     void (*Process)(ALfloat*, const ALfloat*, ALuint, const ALuint, ALuint);
  37
  38     ALuint index;
  39     ALuint step;
  40
  41     ALfloat Gain[MAX_EFFECT_CHANNELS][MAX_OUTPUT_CHANNELS];
  42
  43     ALfilterState Filter[MAX_EFFECT_CHANNELS];
  44 } ALmodulatorState;
  45
  46 #define WAVEFORM_FRACBITS  24
  47 #define WAVEFORM_FRACONE   (1<<WAVEFORM_FRACBITS)
  48 #define WAVEFORM_FRACMASK  (WAVEFORM_FRACONE-1)
  49
  50 static inline ALfloat Sin(ALuint index)
  51 {
  52     return sinf(index*(F_TAU/WAVEFORM_FRACONE) - F_PI)*0.5f + 0.5f;
  53 }
  54
  55 static inline ALfloat Saw(ALuint index)
  56 {
  57     return (ALfloat)index / WAVEFORM_FRACONE;
  58 }
  59
  60 static inline ALfloat Square(ALuint index)
  61 {
  62     return (ALfloat)((index >> (WAVEFORM_FRACBITS - 1)) & 1);
  63 }
  64
  65 #define DECL_TEMPLATE(func)                                                   \
  66 static void Modulate##func(ALfloat *restrict dst, const ALfloat *restrict src,\
  67                            ALuint index, const ALuint step, ALuint todo)      \
  68 {                                                                             \
  69     ALuint i;                                                                 \
  70     for(i = 0;i < todo;i++)                                                   \
  71     {                                                                         \
  72         index += step;                                                        \
  73         index &= WAVEFORM_FRACMASK;                                           \
  74         dst[i] = src[i] * func(index);                                        \
  75     }                                                                         \
  76 }
  77
  78 DECL_TEMPLATE(Sin)
  79 DECL_TEMPLATE(Saw)
  80 DECL_TEMPLATE(Square)
  81
  82 #undef DECL_TEMPLATE
  83
  84
  85 static ALvoid ALmodulatorState_Destruct(ALmodulatorState *state)
  86 {
  87     ALeffectState_Destruct(STATIC_CAST(ALeffectState,state));
  88 }
  89
  90 static ALboolean ALmodulatorState_deviceUpdate(ALmodulatorState *UNUSED(state), ALCdevice *UNUSED(device))
  91 {
  92     return AL_TRUE;
  93 }
  94
  95 static ALvoid ALmodulatorState_update(ALmodulatorState *state, const ALCdevice *Device, const ALeffectslot *Slot, const ALeffectProps *props)
  96 {
  97     aluMatrixf matrix;
  98     ALfloat cw, a;
  99     ALuint i;
 100
 101     if(props->Modulator.Waveform == AL_RING_MODULATOR_SINUSOID)
 102         state->Process = ModulateSin;
 103     else if(props->Modulator.Waveform == AL_RING_MODULATOR_SAWTOOTH)
 104         state->Process = ModulateSaw;
 105     else /*if(Slot->Params.EffectProps.Modulator.Waveform == AL_RING_MODULATOR_SQUARE)*/
 106         state->Process = ModulateSquare;
 107
 108     state->step = fastf2u(props->Modulator.Frequency*WAVEFORM_FRACONE /
 109                           Device->Frequency);
 110     if(state->step == 0) state->step = 1;
 111
 112     /* Custom filter coeffs, which match the old version instead of a low-shelf. */
 113     cw = cosf(F_TAU * props->Modulator.HighPassCutoff / Device->Frequency);
 114     a = (2.0f-cw) - sqrtf(powf(2.0f-cw, 2.0f) - 1.0f);
 115
 116     for(i = 0;i < MAX_EFFECT_CHANNELS;i++)
 117     {
 118         state->Filter[i].a1 = -a;
 119         state->Filter[i].a2 = 0.0f;
 120         state->Filter[i].b0 = a;
 121         state->Filter[i].b1 = -a;
 122         state->Filter[i].b2 = 0.0f;
 123         state->Filter[i].process = ALfilterState_processC;
 124     }
 125
 126     aluMatrixfSet(&matrix,
 127         1.0f, 0.0f, 0.0f, 0.0f,
 128         0.0f, 1.0f, 0.0f, 0.0f,
 129         0.0f, 0.0f, 1.0f, 0.0f,
 130         0.0f, 0.0f, 0.0f, 1.0f
 131     );
 132
 133     STATIC_CAST(ALeffectState,state)->OutBuffer = Device->FOAOut.Buffer;
 134     STATIC_CAST(ALeffectState,state)->OutChannels = Device->FOAOut.NumChannels;
 135     for(i = 0;i < MAX_EFFECT_CHANNELS;i++)
 136         ComputeFirstOrderGains(Device->FOAOut, matrix.m[i], Slot->Params.Gain,
 137                                state->Gain[i]);
 138 }
 139
 140 static ALvoid ALmodulatorState_process(ALmodulatorState *state, ALuint SamplesToDo, const ALfloat (*restrict SamplesIn)[BUFFERSIZE], ALfloat (*restrict SamplesOut)[BUFFERSIZE], ALuint NumChannels)
 141 {
 142     const ALuint step = state->step;
 143     ALuint index = state->index;
 144     ALuint base;
 145
 146     for(base = 0;base < SamplesToDo;)
 147     {
 148         ALfloat temps[2][128];
 149         ALuint td = minu(128, SamplesToDo-base);
 150         ALuint i, j, k;
 151
 152         for(j = 0;j < MAX_EFFECT_CHANNELS;j++)
 153         {
 154             ALfilterState_process(&state->Filter[j], temps[0], &SamplesIn[j][base], td);
 155             state->Process(temps[1], temps[0], index, step, td);
 156
 157             for(k = 0;k < NumChannels;k++)
 158             {
 159                 ALfloat gain = state->Gain[j][k];
 160                 if(!(fabsf(gain) > GAIN_SILENCE_THRESHOLD))
 161                     continue;
 162
 163                 for(i = 0;i < td;i++)
 164                     SamplesOut[k][base+i] += gain * temps[1][i];
 165             }
 166         }
 167
 168         for(i = 0;i < td;i++)
 169         {
 170             index += step;
 171             index &= WAVEFORM_FRACMASK;
 172         }
 173         base += td;
 174     }
 175     state->index = index;
 176 }
 177
 178 DECLARE_DEFAULT_ALLOCATORS(ALmodulatorState)
 179
 180 DEFINE_ALEFFECTSTATE_VTABLE(ALmodulatorState);
 181
 182
 183 typedef struct ALmodulatorStateFactory {
 184     DERIVE_FROM_TYPE(ALeffectStateFactory);
 185 } ALmodulatorStateFactory;
 186
 187 static ALeffectState *ALmodulatorStateFactory_create(ALmodulatorStateFactory *UNUSED(factory))
 188 {
 189     ALmodulatorState *state;
 190     ALuint i;
 191
 192     state = ALmodulatorState_New(sizeof(*state));
 193     if(!state) return NULL;
 194     SET_VTABLE2(ALmodulatorState, ALeffectState, state);
 195
 196     state->index = 0;
 197     state->step = 1;
 198
 199     for(i = 0;i < MAX_EFFECT_CHANNELS;i++)
 200         ALfilterState_clear(&state->Filter[i]);
 201
 202     return STATIC_CAST(ALeffectState, state);
 203 }
 204
 205 DEFINE_ALEFFECTSTATEFACTORY_VTABLE(ALmodulatorStateFactory);
 206
 207 ALeffectStateFactory *ALmodulatorStateFactory_getFactory(void)
 208 {
 209     static ALmodulatorStateFactory ModulatorFactory = { { GET_VTABLE2(ALmodulatorStateFactory, ALeffectStateFactory) } };
 210
 211     return STATIC_CAST(ALeffectStateFactory, &ModulatorFactory);
 212 }
 213
 214
 215 void ALmodulator_setParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val)
 216 {
 217     ALeffectProps *props = &effect->Props;
 218     switch(param)
 219     {
 220         case AL_RING_MODULATOR_FREQUENCY:
 221             if(!(val >= AL_RING_MODULATOR_MIN_FREQUENCY && val <= AL_RING_MODULATOR_MAX_FREQUENCY))
 222                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 223             props->Modulator.Frequency = val;
 224             break;
 225
 226         case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
 227             if(!(val >= AL_RING_MODULATOR_MIN_HIGHPASS_CUTOFF && val <= AL_RING_MODULATOR_MAX_HIGHPASS_CUTOFF))
 228                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 229             props->Modulator.HighPassCutoff = val;
 230             break;
 231
 232         default:
 233             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 234     }
 235 }
 236 void ALmodulator_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals)
 237 {
 238     ALmodulator_setParamf(effect, context, param, vals[0]);
 239 }
 240 void ALmodulator_setParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val)
 241 {
 242     ALeffectProps *props = &effect->Props;
 243     switch(param)
 244     {
 245         case AL_RING_MODULATOR_FREQUENCY:
 246         case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
 247             ALmodulator_setParamf(effect, context, param, (ALfloat)val);
 248             break;
 249
 250         case AL_RING_MODULATOR_WAVEFORM:
 251             if(!(val >= AL_RING_MODULATOR_MIN_WAVEFORM && val <= AL_RING_MODULATOR_MAX_WAVEFORM))
 252                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 253             props->Modulator.Waveform = val;
 254             break;
 255
 256         default:
 257             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 258     }
 259 }
 260 void ALmodulator_setParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals)
 261 {
 262     ALmodulator_setParami(effect, context, param, vals[0]);
 263 }
 264
 265 void ALmodulator_getParami(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *val)
 266 {
 267     const ALeffectProps *props = &effect->Props;
 268     switch(param)
 269     {
 270         case AL_RING_MODULATOR_FREQUENCY:
 271             *val = (ALint)props->Modulator.Frequency;
 272             break;
 273         case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
 274             *val = (ALint)props->Modulator.HighPassCutoff;
 275             break;
 276         case AL_RING_MODULATOR_WAVEFORM:
 277             *val = props->Modulator.Waveform;
 278             break;
 279
 280         default:
 281             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 282     }
 283 }
 284 void ALmodulator_getParamiv(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals)
 285 {
 286     ALmodulator_getParami(effect, context, param, vals);
 287 }
 288 void ALmodulator_getParamf(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val)
 289 {
 290     const ALeffectProps *props = &effect->Props;
 291     switch(param)
 292     {
 293         case AL_RING_MODULATOR_FREQUENCY:
 294             *val = props->Modulator.Frequency;
 295             break;
 296         case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
 297             *val = props->Modulator.HighPassCutoff;
 298             break;
 299
 300         default:
 301             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 302     }
 303 }
 304 void ALmodulator_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals)
 305 {
 306     ALmodulator_getParamf(effect, context, param, vals);
 307 }
 308
 309 DEFINE_ALEFFECT_VTABLE(ALmodulator);