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-rw-r--r--Alc/effects/modulator.c306
1 files changed, 306 insertions, 0 deletions
diff --git a/Alc/effects/modulator.c b/Alc/effects/modulator.c
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+/**
+ * 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;
+ }
+}
+
+static void ALmodulatorState_Delete(ALmodulatorState *state)
+{
+ free(state);
+}
+
+DEFINE_ALEFFECTSTATE_VTABLE(ALmodulatorState);
+
+
+typedef struct ALmodulatorStateFactory {
+ DERIVE_FROM_TYPE(ALeffectStateFactory);
+} ALmodulatorStateFactory;
+
+static ALeffectState *ALmodulatorStateFactory_create(ALmodulatorStateFactory *UNUSED(factory))
+{
+ ALmodulatorState *state;
+
+ state = malloc(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);
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