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 static ALvoid ALmodulatorState_Destruct(ALmodulatorState *state);
  47 static ALboolean ALmodulatorState_deviceUpdate(ALmodulatorState *state, ALCdevice *device);
  48 static ALvoid ALmodulatorState_update(ALmodulatorState *state, const ALCdevice *Device, const ALeffectslot *Slot, const ALeffectProps *props);
  49 static ALvoid ALmodulatorState_process(ALmodulatorState *state, ALuint SamplesToDo, const ALfloat (*restrict SamplesIn)[BUFFERSIZE], ALfloat (*restrict SamplesOut)[BUFFERSIZE], ALuint NumChannels);
  50 DECLARE_DEFAULT_ALLOCATORS(ALmodulatorState)
  51
  52 DEFINE_ALEFFECTSTATE_VTABLE(ALmodulatorState);
  53
  54
  55 #define WAVEFORM_FRACBITS  24
  56 #define WAVEFORM_FRACONE   (1<<WAVEFORM_FRACBITS)
  57 #define WAVEFORM_FRACMASK  (WAVEFORM_FRACONE-1)
  58
  59 static inline ALfloat Sin(ALuint index)
  60 {
  61     return sinf(index*(F_TAU/WAVEFORM_FRACONE) - F_PI)*0.5f + 0.5f;
  62 }
  63
  64 static inline ALfloat Saw(ALuint index)
  65 {
  66     return (ALfloat)index / WAVEFORM_FRACONE;
  67 }
  68
  69 static inline ALfloat Square(ALuint index)
  70 {
  71     return (ALfloat)((index >> (WAVEFORM_FRACBITS - 1)) & 1);
  72 }
  73
  74 #define DECL_TEMPLATE(func)                                                   \
  75 static void Modulate##func(ALfloat *restrict dst, const ALfloat *restrict src,\
  76                            ALuint index, const ALuint step, ALuint todo)      \
  77 {                                                                             \
  78     ALuint i;                                                                 \
  79     for(i = 0;i < todo;i++)                                                   \
  80     {                                                                         \
  81         index += step;                                                        \
  82         index &= WAVEFORM_FRACMASK;                                           \
  83         dst[i] = src[i] * func(index);                                        \
  84     }                                                                         \
  85 }
  86
  87 DECL_TEMPLATE(Sin)
  88 DECL_TEMPLATE(Saw)
  89 DECL_TEMPLATE(Square)
  90
  91 #undef DECL_TEMPLATE
  92
  93
  94 static void ALmodulatorState_Construct(ALmodulatorState *state)
  95 {
  96     ALuint i;
  97
  98     ALeffectState_Construct(STATIC_CAST(ALeffectState, state));
  99     SET_VTABLE2(ALmodulatorState, ALeffectState, state);
 100
 101     state->index = 0;
 102     state->step = 1;
 103
 104     for(i = 0;i < MAX_EFFECT_CHANNELS;i++)
 105         ALfilterState_clear(&state->Filter[i]);
 106 }
 107
 108 static ALvoid ALmodulatorState_Destruct(ALmodulatorState *state)
 109 {
 110     ALeffectState_Destruct(STATIC_CAST(ALeffectState,state));
 111 }
 112
 113 static ALboolean ALmodulatorState_deviceUpdate(ALmodulatorState *UNUSED(state), ALCdevice *UNUSED(device))
 114 {
 115     return AL_TRUE;
 116 }
 117
 118 static ALvoid ALmodulatorState_update(ALmodulatorState *state, const ALCdevice *Device, const ALeffectslot *Slot, const ALeffectProps *props)
 119 {
 120     ALfloat cw, a;
 121     ALuint i;
 122
 123     if(props->Modulator.Waveform == AL_RING_MODULATOR_SINUSOID)
 124         state->Process = ModulateSin;
 125     else if(props->Modulator.Waveform == AL_RING_MODULATOR_SAWTOOTH)
 126         state->Process = ModulateSaw;
 127     else /*if(Slot->Params.EffectProps.Modulator.Waveform == AL_RING_MODULATOR_SQUARE)*/
 128         state->Process = ModulateSquare;
 129
 130     state->step = fastf2u(props->Modulator.Frequency*WAVEFORM_FRACONE /
 131                           Device->Frequency);
 132     if(state->step == 0) state->step = 1;
 133
 134     /* Custom filter coeffs, which match the old version instead of a low-shelf. */
 135     cw = cosf(F_TAU * props->Modulator.HighPassCutoff / Device->Frequency);
 136     a = (2.0f-cw) - sqrtf(powf(2.0f-cw, 2.0f) - 1.0f);
 137
 138     for(i = 0;i < MAX_EFFECT_CHANNELS;i++)
 139     {
 140         state->Filter[i].b0 = a;
 141         state->Filter[i].b1 = -a;
 142         state->Filter[i].b2 = 0.0f;
 143         state->Filter[i].a1 = -a;
 144         state->Filter[i].a2 = 0.0f;
 145     }
 146
 147     STATIC_CAST(ALeffectState,state)->OutBuffer = Device->FOAOut.Buffer;
 148     STATIC_CAST(ALeffectState,state)->OutChannels = Device->FOAOut.NumChannels;
 149     for(i = 0;i < MAX_EFFECT_CHANNELS;i++)
 150         ComputeFirstOrderGains(Device->FOAOut, IdentityMatrixf.m[i],
 151                                Slot->Params.Gain, state->Gain[i]);
 152 }
 153
 154 static ALvoid ALmodulatorState_process(ALmodulatorState *state, ALuint SamplesToDo, const ALfloat (*restrict SamplesIn)[BUFFERSIZE], ALfloat (*restrict SamplesOut)[BUFFERSIZE], ALuint NumChannels)
 155 {
 156     const ALuint step = state->step;
 157     ALuint index = state->index;
 158     ALuint base;
 159
 160     for(base = 0;base < SamplesToDo;)
 161     {
 162         ALfloat temps[2][128];
 163         ALuint td = minu(128, SamplesToDo-base);
 164         ALuint i, j, k;
 165
 166         for(j = 0;j < MAX_EFFECT_CHANNELS;j++)
 167         {
 168             ALfilterState_process(&state->Filter[j], temps[0], &SamplesIn[j][base], td);
 169             state->Process(temps[1], temps[0], index, step, td);
 170
 171             for(k = 0;k < NumChannels;k++)
 172             {
 173                 ALfloat gain = state->Gain[j][k];
 174                 if(!(fabsf(gain) > GAIN_SILENCE_THRESHOLD))
 175                     continue;
 176
 177                 for(i = 0;i < td;i++)
 178                     SamplesOut[k][base+i] += gain * temps[1][i];
 179             }
 180         }
 181
 182         for(i = 0;i < td;i++)
 183         {
 184             index += step;
 185             index &= WAVEFORM_FRACMASK;
 186         }
 187         base += td;
 188     }
 189     state->index = index;
 190 }
 191
 192
 193 typedef struct ALmodulatorStateFactory {
 194     DERIVE_FROM_TYPE(ALeffectStateFactory);
 195 } ALmodulatorStateFactory;
 196
 197 static ALeffectState *ALmodulatorStateFactory_create(ALmodulatorStateFactory *UNUSED(factory))
 198 {
 199     ALmodulatorState *state;
 200
 201     NEW_OBJ0(state, ALmodulatorState)();
 202     if(!state) return NULL;
 203
 204     return STATIC_CAST(ALeffectState, state);
 205 }
 206
 207 DEFINE_ALEFFECTSTATEFACTORY_VTABLE(ALmodulatorStateFactory);
 208
 209 ALeffectStateFactory *ALmodulatorStateFactory_getFactory(void)
 210 {
 211     static ALmodulatorStateFactory ModulatorFactory = { { GET_VTABLE2(ALmodulatorStateFactory, ALeffectStateFactory) } };
 212
 213     return STATIC_CAST(ALeffectStateFactory, &ModulatorFactory);
 214 }
 215
 216
 217 void ALmodulator_setParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val)
 218 {
 219     ALeffectProps *props = &effect->Props;
 220     switch(param)
 221     {
 222         case AL_RING_MODULATOR_FREQUENCY:
 223             if(!(val >= AL_RING_MODULATOR_MIN_FREQUENCY && val <= AL_RING_MODULATOR_MAX_FREQUENCY))
 224                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 225             props->Modulator.Frequency = val;
 226             break;
 227
 228         case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
 229             if(!(val >= AL_RING_MODULATOR_MIN_HIGHPASS_CUTOFF && val <= AL_RING_MODULATOR_MAX_HIGHPASS_CUTOFF))
 230                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 231             props->Modulator.HighPassCutoff = val;
 232             break;
 233
 234         default:
 235             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 236     }
 237 }
 238 void ALmodulator_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals)
 239 {
 240     ALmodulator_setParamf(effect, context, param, vals[0]);
 241 }
 242 void ALmodulator_setParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val)
 243 {
 244     ALeffectProps *props = &effect->Props;
 245     switch(param)
 246     {
 247         case AL_RING_MODULATOR_FREQUENCY:
 248         case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
 249             ALmodulator_setParamf(effect, context, param, (ALfloat)val);
 250             break;
 251
 252         case AL_RING_MODULATOR_WAVEFORM:
 253             if(!(val >= AL_RING_MODULATOR_MIN_WAVEFORM && val <= AL_RING_MODULATOR_MAX_WAVEFORM))
 254                 SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
 255             props->Modulator.Waveform = val;
 256             break;
 257
 258         default:
 259             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 260     }
 261 }
 262 void ALmodulator_setParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals)
 263 {
 264     ALmodulator_setParami(effect, context, param, vals[0]);
 265 }
 266
 267 void ALmodulator_getParami(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *val)
 268 {
 269     const ALeffectProps *props = &effect->Props;
 270     switch(param)
 271     {
 272         case AL_RING_MODULATOR_FREQUENCY:
 273             *val = (ALint)props->Modulator.Frequency;
 274             break;
 275         case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
 276             *val = (ALint)props->Modulator.HighPassCutoff;
 277             break;
 278         case AL_RING_MODULATOR_WAVEFORM:
 279             *val = props->Modulator.Waveform;
 280             break;
 281
 282         default:
 283             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 284     }
 285 }
 286 void ALmodulator_getParamiv(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals)
 287 {
 288     ALmodulator_getParami(effect, context, param, vals);
 289 }
 290 void ALmodulator_getParamf(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val)
 291 {
 292     const ALeffectProps *props = &effect->Props;
 293     switch(param)
 294     {
 295         case AL_RING_MODULATOR_FREQUENCY:
 296             *val = props->Modulator.Frequency;
 297             break;
 298         case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
 299             *val = props->Modulator.HighPassCutoff;
 300             break;
 301
 302         default:
 303             SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
 304     }
 305 }
 306 void ALmodulator_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals)
 307 {
 308     ALmodulator_getParamf(effect, context, param, vals);
 309 }
 310
 311 DEFINE_ALEFFECT_VTABLE(ALmodulator);