AuroraOpenALSoft/Alc/effects/modulator.c
2014-03-21 23:56:18 -07:00

304 lines
11 KiB
C

/**
* OpenAL cross platform audio library
* Copyright (C) 2009 by Chris Robinson.
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
* Or go to http://www.gnu.org/copyleft/lgpl.html
*/
#include "config.h"
#include <math.h>
#include <stdlib.h>
#include "alMain.h"
#include "alFilter.h"
#include "alAuxEffectSlot.h"
#include "alError.h"
#include "alu.h"
typedef struct ALmodulatorState {
DERIVE_FROM_TYPE(ALeffectState);
enum {
SINUSOID,
SAWTOOTH,
SQUARE
} Waveform;
ALuint index;
ALuint step;
ALfloat Gain[MaxChannels];
ALfilterState Filter;
} ALmodulatorState;
#define WAVEFORM_FRACBITS 24
#define WAVEFORM_FRACONE (1<<WAVEFORM_FRACBITS)
#define WAVEFORM_FRACMASK (WAVEFORM_FRACONE-1)
static inline ALfloat Sin(ALuint index)
{
return sinf(index*(F_2PI/WAVEFORM_FRACONE) - F_PI)*0.5f + 0.5f;
}
static inline ALfloat Saw(ALuint index)
{
return (ALfloat)index / WAVEFORM_FRACONE;
}
static inline ALfloat Square(ALuint index)
{
return (ALfloat)((index >> (WAVEFORM_FRACBITS - 1)) & 1);
}
#define DECL_TEMPLATE(func) \
static void Process##func(ALmodulatorState *state, ALuint SamplesToDo, \
const ALfloat *restrict SamplesIn, \
ALfloat (*restrict SamplesOut)[BUFFERSIZE]) \
{ \
const ALuint step = state->step; \
ALuint index = state->index; \
ALuint base; \
\
for(base = 0;base < SamplesToDo;) \
{ \
ALfloat temps[64]; \
ALuint td = minu(SamplesToDo-base, 64); \
ALuint i, k; \
\
for(i = 0;i < td;i++) \
{ \
ALfloat samp; \
samp = SamplesIn[base+i]; \
samp = ALfilterState_processSingle(&state->Filter, samp); \
\
index += step; \
index &= WAVEFORM_FRACMASK; \
temps[i] = samp * func(index); \
} \
\
for(k = 0;k < MaxChannels;k++) \
{ \
ALfloat gain = state->Gain[k]; \
if(!(gain > GAIN_SILENCE_THRESHOLD)) \
continue; \
\
for(i = 0;i < td;i++) \
SamplesOut[k][base+i] += gain * temps[i]; \
} \
\
base += td; \
} \
state->index = index; \
}
DECL_TEMPLATE(Sin)
DECL_TEMPLATE(Saw)
DECL_TEMPLATE(Square)
#undef DECL_TEMPLATE
static ALvoid ALmodulatorState_Destruct(ALmodulatorState *UNUSED(state))
{
}
static ALboolean ALmodulatorState_deviceUpdate(ALmodulatorState *UNUSED(state), ALCdevice *UNUSED(device))
{
return AL_TRUE;
}
static ALvoid ALmodulatorState_update(ALmodulatorState *state, ALCdevice *Device, const ALeffectslot *Slot)
{
ALfloat gain, cw, a;
if(Slot->EffectProps.Modulator.Waveform == AL_RING_MODULATOR_SINUSOID)
state->Waveform = SINUSOID;
else if(Slot->EffectProps.Modulator.Waveform == AL_RING_MODULATOR_SAWTOOTH)
state->Waveform = SAWTOOTH;
else if(Slot->EffectProps.Modulator.Waveform == AL_RING_MODULATOR_SQUARE)
state->Waveform = SQUARE;
state->step = fastf2u(Slot->EffectProps.Modulator.Frequency*WAVEFORM_FRACONE /
Device->Frequency);
if(state->step == 0) state->step = 1;
/* Custom filter coeffs, which match the old version instead of a low-shelf. */
cw = cosf(F_2PI * Slot->EffectProps.Modulator.HighPassCutoff / Device->Frequency);
a = (2.0f-cw) - sqrtf(powf(2.0f-cw, 2.0f) - 1.0f);
state->Filter.b[0] = a;
state->Filter.b[1] = -a;
state->Filter.b[2] = 0.0f;
state->Filter.a[0] = 1.0f;
state->Filter.a[1] = -a;
state->Filter.a[2] = 0.0f;
gain = sqrtf(1.0f/Device->NumChan) * Slot->Gain;
SetGains(Device, gain, state->Gain);
}
static ALvoid ALmodulatorState_process(ALmodulatorState *state, ALuint SamplesToDo, const ALfloat *restrict SamplesIn, ALfloat (*restrict SamplesOut)[BUFFERSIZE])
{
switch(state->Waveform)
{
case SINUSOID:
ProcessSin(state, SamplesToDo, SamplesIn, SamplesOut);
break;
case SAWTOOTH:
ProcessSaw(state, SamplesToDo, SamplesIn, SamplesOut);
break;
case SQUARE:
ProcessSquare(state, SamplesToDo, SamplesIn, SamplesOut);
break;
}
}
DECLARE_DEFAULT_ALLOCATORS(ALmodulatorState)
DEFINE_ALEFFECTSTATE_VTABLE(ALmodulatorState);
typedef struct ALmodulatorStateFactory {
DERIVE_FROM_TYPE(ALeffectStateFactory);
} ALmodulatorStateFactory;
static ALeffectState *ALmodulatorStateFactory_create(ALmodulatorStateFactory *UNUSED(factory))
{
ALmodulatorState *state;
state = ALmodulatorState_New(sizeof(*state));
if(!state) return NULL;
SET_VTABLE2(ALmodulatorState, ALeffectState, state);
state->index = 0;
state->step = 1;
ALfilterState_clear(&state->Filter);
return STATIC_CAST(ALeffectState, state);
}
DEFINE_ALEFFECTSTATEFACTORY_VTABLE(ALmodulatorStateFactory);
ALeffectStateFactory *ALmodulatorStateFactory_getFactory(void)
{
static ALmodulatorStateFactory ModulatorFactory = { { GET_VTABLE2(ALmodulatorStateFactory, ALeffectStateFactory) } };
return STATIC_CAST(ALeffectStateFactory, &ModulatorFactory);
}
void ALmodulator_setParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val)
{
ALeffectProps *props = &effect->Props;
switch(param)
{
case AL_RING_MODULATOR_FREQUENCY:
if(!(val >= AL_RING_MODULATOR_MIN_FREQUENCY && val <= AL_RING_MODULATOR_MAX_FREQUENCY))
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
props->Modulator.Frequency = val;
break;
case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
if(!(val >= AL_RING_MODULATOR_MIN_HIGHPASS_CUTOFF && val <= AL_RING_MODULATOR_MAX_HIGHPASS_CUTOFF))
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
props->Modulator.HighPassCutoff = val;
break;
default:
SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
}
}
void ALmodulator_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals)
{
ALmodulator_setParamf(effect, context, param, vals[0]);
}
void ALmodulator_setParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val)
{
ALeffectProps *props = &effect->Props;
switch(param)
{
case AL_RING_MODULATOR_FREQUENCY:
case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
ALmodulator_setParamf(effect, context, param, (ALfloat)val);
break;
case AL_RING_MODULATOR_WAVEFORM:
if(!(val >= AL_RING_MODULATOR_MIN_WAVEFORM && val <= AL_RING_MODULATOR_MAX_WAVEFORM))
SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
props->Modulator.Waveform = val;
break;
default:
SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
}
}
void ALmodulator_setParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals)
{
ALmodulator_setParami(effect, context, param, vals[0]);
}
void ALmodulator_getParami(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *val)
{
const ALeffectProps *props = &effect->Props;
switch(param)
{
case AL_RING_MODULATOR_FREQUENCY:
*val = (ALint)props->Modulator.Frequency;
break;
case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
*val = (ALint)props->Modulator.HighPassCutoff;
break;
case AL_RING_MODULATOR_WAVEFORM:
*val = props->Modulator.Waveform;
break;
default:
SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
}
}
void ALmodulator_getParamiv(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals)
{
ALmodulator_getParami(effect, context, param, vals);
}
void ALmodulator_getParamf(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val)
{
const ALeffectProps *props = &effect->Props;
switch(param)
{
case AL_RING_MODULATOR_FREQUENCY:
*val = props->Modulator.Frequency;
break;
case AL_RING_MODULATOR_HIGHPASS_CUTOFF:
*val = props->Modulator.HighPassCutoff;
break;
default:
SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
}
}
void ALmodulator_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals)
{
ALmodulator_getParamf(effect, context, param, vals);
}
DEFINE_ALEFFECT_VTABLE(ALmodulator);