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-rw-r--r--Alc/effects/flanger.c411
1 files changed, 411 insertions, 0 deletions
diff --git a/Alc/effects/flanger.c b/Alc/effects/flanger.c
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+++ b/Alc/effects/flanger.c
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+/**
+ * OpenAL cross platform audio library
+ * Copyright (C) 2013 by Mike Gorchak
+ * 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 ALflangerStateFactory {
+ DERIVE_FROM_TYPE(ALeffectStateFactory);
+} ALflangerStateFactory;
+
+static ALflangerStateFactory FlangerFactory;
+
+
+typedef struct ALflangerState {
+ DERIVE_FROM_TYPE(ALeffectState);
+
+ ALfloat *SampleBufferLeft;
+ ALfloat *SampleBufferRight;
+ ALuint BufferLength;
+ ALint offset;
+ ALfloat lfo_coeff;
+ ALint lfo_disp;
+
+ /* Gains for left and right sides */
+ ALfloat Gain[2][MaxChannels];
+
+ /* effect parameters */
+ ALint waveform;
+ ALint delay;
+ ALfloat depth;
+ ALfloat feedback;
+} ALflangerState;
+
+static ALvoid ALflangerState_Destruct(ALflangerState *state)
+{
+ free(state->SampleBufferLeft);
+ state->SampleBufferLeft = NULL;
+
+ free(state->SampleBufferRight);
+ state->SampleBufferRight = NULL;
+}
+
+static ALboolean ALflangerState_DeviceUpdate(ALflangerState *state, ALCdevice *Device)
+{
+ ALuint maxlen;
+ ALuint it;
+
+ maxlen = fastf2u(AL_FLANGER_MAX_DELAY * 3.0f * Device->Frequency) + 1;
+ maxlen = NextPowerOf2(maxlen);
+
+ if(maxlen != state->BufferLength)
+ {
+ void *temp;
+
+ temp = realloc(state->SampleBufferLeft, maxlen * sizeof(ALfloat));
+ if(!temp) return AL_FALSE;
+ state->SampleBufferLeft = temp;
+
+ temp = realloc(state->SampleBufferRight, maxlen * sizeof(ALfloat));
+ if(!temp) return AL_FALSE;
+ state->SampleBufferRight = temp;
+
+ state->BufferLength = maxlen;
+ }
+
+ for(it = 0;it < state->BufferLength;it++)
+ {
+ state->SampleBufferLeft[it] = 0.0f;
+ state->SampleBufferRight[it] = 0.0f;
+ }
+
+ return AL_TRUE;
+}
+
+static ALvoid ALflangerState_Update(ALflangerState *state, ALCdevice *Device, const ALeffectslot *Slot)
+{
+ ALfloat frequency = (ALfloat)Device->Frequency;
+ ALfloat rate;
+ ALint phase;
+ ALuint it;
+
+ for(it = 0;it < MaxChannels;it++)
+ {
+ state->Gain[0][it] = 0.0f;
+ state->Gain[1][it] = 0.0f;
+ }
+
+ state->waveform = Slot->effect.Flanger.Waveform;
+ state->depth = Slot->effect.Flanger.Depth;
+ state->feedback = Slot->effect.Flanger.Feedback;
+ state->delay = fastf2i(Slot->effect.Flanger.Delay * frequency);
+
+ /* Gains for left and right sides */
+ ComputeAngleGains(Device, atan2f(-1.0f, 0.0f), 0.0f, Slot->Gain, state->Gain[0]);
+ ComputeAngleGains(Device, atan2f(+1.0f, 0.0f), 0.0f, Slot->Gain, state->Gain[1]);
+
+ phase = Slot->effect.Flanger.Phase;
+ rate = Slot->effect.Flanger.Rate;
+
+ /* Calculate LFO coefficient */
+ switch(state->waveform)
+ {
+ case AL_FLANGER_WAVEFORM_TRIANGLE:
+ if(rate == 0.0f)
+ state->lfo_coeff = 0.0f;
+ else
+ state->lfo_coeff = 1.0f / (frequency / rate);
+ break;
+ case AL_FLANGER_WAVEFORM_SINUSOID:
+ if(rate == 0.0f)
+ state->lfo_coeff = 0.0f;
+ else
+ state->lfo_coeff = F_PI * 2.0f / (frequency / rate);
+ break;
+ }
+
+ /* Calculate lfo phase displacement */
+ if(phase == 0 || rate == 0.0f)
+ state->lfo_disp = 0;
+ else
+ state->lfo_disp = fastf2i(frequency / rate / (360.0f/phase));
+}
+
+static __inline void Triangle(ALint *delay_left, ALint *delay_right, ALint offset, const ALflangerState *state)
+{
+ ALfloat lfo_value;
+
+ lfo_value = 2.0f - fabsf(2.0f - fmodf(state->lfo_coeff * offset * 4.0f, 4.0f));
+ lfo_value *= state->depth * state->delay;
+ *delay_left = fastf2i(lfo_value) + state->delay;
+
+ lfo_value = 2.0f - fabsf(2.0f - fmodf(state->lfo_coeff *
+ (offset+state->lfo_disp) * 4.0f,
+ 4.0f));
+ lfo_value *= state->depth * state->delay;
+ *delay_right = fastf2i(lfo_value) + state->delay;
+}
+
+static __inline void Sinusoid(ALint *delay_left, ALint *delay_right, ALint offset, const ALflangerState *state)
+{
+ ALfloat lfo_value;
+
+ lfo_value = 1.0f + sinf(fmodf(state->lfo_coeff * offset, 2.0f*F_PI));
+ lfo_value *= state->depth * state->delay;
+ *delay_left = fastf2i(lfo_value) + state->delay;
+
+ lfo_value = 1.0f + sinf(fmodf(state->lfo_coeff * (offset+state->lfo_disp),
+ 2.0f*F_PI));
+ lfo_value *= state->depth * state->delay;
+ *delay_right = fastf2i(lfo_value) + state->delay;
+}
+
+#define DECL_TEMPLATE(func) \
+static void Process##func(ALflangerState *state, ALuint SamplesToDo, \
+ const ALfloat *restrict SamplesIn, \
+ ALfloat (*restrict SamplesOut)[BUFFERSIZE]) \
+{ \
+ const ALint mask = state->BufferLength-1; \
+ ALint offset = state->offset; \
+ ALuint it, kt; \
+ ALuint base; \
+ \
+ for(base = 0;base < SamplesToDo;) \
+ { \
+ ALfloat temps[64][2]; \
+ ALuint td = minu(SamplesToDo-base, 64); \
+ \
+ for(it = 0;it < td;it++,offset++) \
+ { \
+ ALint delay_left, delay_right; \
+ (func)(&delay_left, &delay_right, offset, state); \
+ \
+ temps[it][0] = state->SampleBufferLeft[(offset-delay_left)&mask]; \
+ state->SampleBufferLeft[offset&mask] = (temps[it][0] + \
+ SamplesIn[it+base]) * \
+ state->feedback; \
+ \
+ temps[it][1] = state->SampleBufferRight[(offset-delay_right)&mask];\
+ state->SampleBufferRight[offset&mask] = (temps[it][1] + \
+ SamplesIn[it+base]) * \
+ state->feedback; \
+ } \
+ \
+ for(kt = 0;kt < MaxChannels;kt++) \
+ { \
+ ALfloat gain = state->Gain[0][kt]; \
+ if(gain > 0.00001f) \
+ { \
+ for(it = 0;it < td;it++) \
+ SamplesOut[kt][it+base] += temps[it][0] * gain; \
+ } \
+ \
+ gain = state->Gain[1][kt]; \
+ if(gain > 0.00001f) \
+ { \
+ for(it = 0;it < td;it++) \
+ SamplesOut[kt][it+base] += temps[it][1] * gain; \
+ } \
+ } \
+ \
+ base += td; \
+ } \
+ \
+ state->offset = offset; \
+}
+
+DECL_TEMPLATE(Triangle)
+DECL_TEMPLATE(Sinusoid)
+
+#undef DECL_TEMPLATE
+
+static ALvoid ALflangerState_Process(ALflangerState *state, ALuint SamplesToDo, const ALfloat *restrict SamplesIn, ALfloat (*restrict SamplesOut)[BUFFERSIZE])
+{
+ if(state->waveform == AL_FLANGER_WAVEFORM_TRIANGLE)
+ ProcessTriangle(state, SamplesToDo, SamplesIn, SamplesOut);
+ else if(state->waveform == AL_FLANGER_WAVEFORM_SINUSOID)
+ ProcessSinusoid(state, SamplesToDo, SamplesIn, SamplesOut);
+}
+
+static ALeffectStateFactory *ALflangerState_getCreator(void)
+{
+ return STATIC_CAST(ALeffectStateFactory, &FlangerFactory);
+}
+
+DEFINE_ALEFFECTSTATE_VTABLE(ALflangerState);
+
+
+ALeffectState *ALflangerStateFactory_create(void)
+{
+ ALflangerState *state;
+
+ state = malloc(sizeof(*state));
+ if(!state) return NULL;
+ SET_VTABLE2(ALflangerState, ALeffectState, state);
+
+ state->BufferLength = 0;
+ state->SampleBufferLeft = NULL;
+ state->SampleBufferRight = NULL;
+ state->offset = 0;
+
+ return STATIC_CAST(ALeffectState, state);
+}
+
+static ALvoid ALflangerStateFactory_destroy(ALeffectState *effect)
+{
+ ALflangerState *state = STATIC_UPCAST(ALflangerState, ALeffectState, effect);
+ ALflangerState_Destruct(state);
+ free(state);
+}
+
+DEFINE_ALEFFECTSTATEFACTORY_VTABLE(ALflangerStateFactory);
+
+
+static void init_flanger_factory(void)
+{
+ SET_VTABLE2(ALflangerStateFactory, ALeffectStateFactory, &FlangerFactory);
+}
+
+ALeffectStateFactory *ALflangerStateFactory_getFactory(void)
+{
+ static pthread_once_t once = PTHREAD_ONCE_INIT;
+ pthread_once(&once, init_flanger_factory);
+ return STATIC_CAST(ALeffectStateFactory, &FlangerFactory);
+}
+
+
+void flanger_SetParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val)
+{
+ switch(param)
+ {
+ case AL_FLANGER_WAVEFORM:
+ if(val >= AL_FLANGER_MIN_WAVEFORM && val <= AL_FLANGER_MAX_WAVEFORM)
+ effect->Flanger.Waveform = val;
+ else
+ alSetError(context, AL_INVALID_VALUE);
+ break;
+
+ case AL_FLANGER_PHASE:
+ if(val >= AL_FLANGER_MIN_PHASE && val <= AL_FLANGER_MAX_PHASE)
+ effect->Flanger.Phase = val;
+ else
+ alSetError(context, AL_INVALID_VALUE);
+ break;
+
+ default:
+ alSetError(context, AL_INVALID_ENUM);
+ break;
+ }
+}
+void flanger_SetParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals)
+{
+ flanger_SetParami(effect, context, param, vals[0]);
+}
+void flanger_SetParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val)
+{
+ switch(param)
+ {
+ case AL_FLANGER_RATE:
+ if(val >= AL_FLANGER_MIN_RATE && val <= AL_FLANGER_MAX_RATE)
+ effect->Flanger.Rate = val;
+ else
+ alSetError(context, AL_INVALID_VALUE);
+ break;
+
+ case AL_FLANGER_DEPTH:
+ if(val >= AL_FLANGER_MIN_DEPTH && val <= AL_FLANGER_MAX_DEPTH)
+ effect->Flanger.Depth = val;
+ else
+ alSetError(context, AL_INVALID_VALUE);
+ break;
+
+ case AL_FLANGER_FEEDBACK:
+ if(val >= AL_FLANGER_MIN_FEEDBACK && val <= AL_FLANGER_MAX_FEEDBACK)
+ effect->Flanger.Feedback = val;
+ else
+ alSetError(context, AL_INVALID_VALUE);
+ break;
+
+ case AL_FLANGER_DELAY:
+ if(val >= AL_FLANGER_MIN_DELAY && val <= AL_FLANGER_MAX_DELAY)
+ effect->Flanger.Delay = val;
+ else
+ alSetError(context, AL_INVALID_VALUE);
+ break;
+
+ default:
+ alSetError(context, AL_INVALID_ENUM);
+ break;
+ }
+}
+void flanger_SetParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals)
+{
+ flanger_SetParamf(effect, context, param, vals[0]);
+}
+
+void flanger_GetParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint *val)
+{
+ switch(param)
+ {
+ case AL_FLANGER_WAVEFORM:
+ *val = effect->Flanger.Waveform;
+ break;
+
+ case AL_FLANGER_PHASE:
+ *val = effect->Flanger.Phase;
+ break;
+
+ default:
+ alSetError(context, AL_INVALID_ENUM);
+ break;
+ }
+}
+void flanger_GetParamiv(ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals)
+{
+ flanger_GetParami(effect, context, param, vals);
+}
+void flanger_GetParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val)
+{
+ switch(param)
+ {
+ case AL_FLANGER_RATE:
+ *val = effect->Flanger.Rate;
+ break;
+
+ case AL_FLANGER_DEPTH:
+ *val = effect->Flanger.Depth;
+ break;
+
+ case AL_FLANGER_FEEDBACK:
+ *val = effect->Flanger.Feedback;
+ break;
+
+ case AL_FLANGER_DELAY:
+ *val = effect->Flanger.Delay;
+ break;
+
+ default:
+ alSetError(context, AL_INVALID_ENUM);
+ break;
+ }
+}
+void flanger_GetParamfv(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals)
+{
+ flanger_GetParamf(effect, context, param, vals);
+}