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-rw-r--r--Alc/effects/chorus.c381
1 files changed, 381 insertions, 0 deletions
diff --git a/Alc/effects/chorus.c b/Alc/effects/chorus.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 ALchorusState {
+ DERIVE_FROM_TYPE(ALeffectState);
+
+ ALfloat *SampleBuffer[2];
+ ALuint BufferLength;
+ ALuint offset;
+ ALuint lfo_range;
+ ALfloat lfo_scale;
+ ALint lfo_disp;
+
+ /* Gains for left and right sides */
+ ALfloat Gain[2][MaxChannels];
+
+ /* effect parameters */
+ ALint waveform;
+ ALint delay;
+ ALfloat depth;
+ ALfloat feedback;
+} ALchorusState;
+
+static ALvoid ALchorusState_Destruct(ALchorusState *state)
+{
+ free(state->SampleBuffer[0]);
+ state->SampleBuffer[0] = NULL;
+ state->SampleBuffer[1] = NULL;
+}
+
+static ALboolean ALchorusState_deviceUpdate(ALchorusState *state, ALCdevice *Device)
+{
+ ALuint maxlen;
+ ALuint it;
+
+ maxlen = fastf2u(AL_CHORUS_MAX_DELAY * 3.0f * Device->Frequency) + 1;
+ maxlen = NextPowerOf2(maxlen);
+
+ if(maxlen != state->BufferLength)
+ {
+ void *temp;
+
+ temp = realloc(state->SampleBuffer[0], maxlen * sizeof(ALfloat) * 2);
+ if(!temp) return AL_FALSE;
+ state->SampleBuffer[0] = temp;
+ state->SampleBuffer[1] = state->SampleBuffer[0] + maxlen;
+
+ state->BufferLength = maxlen;
+ }
+
+ for(it = 0;it < state->BufferLength;it++)
+ {
+ state->SampleBuffer[0][it] = 0.0f;
+ state->SampleBuffer[1][it] = 0.0f;
+ }
+
+ return AL_TRUE;
+}
+
+static ALvoid ALchorusState_update(ALchorusState *state, ALCdevice *Device, const ALeffectslot *Slot)
+{
+ ALfloat frequency = (ALfloat)Device->Frequency;
+ ALfloat rate;
+ ALint phase;
+
+ state->waveform = Slot->EffectProps.Chorus.Waveform;
+ state->depth = Slot->EffectProps.Chorus.Depth;
+ state->feedback = Slot->EffectProps.Chorus.Feedback;
+ state->delay = fastf2i(Slot->EffectProps.Chorus.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->EffectProps.Chorus.Phase;
+ rate = Slot->EffectProps.Chorus.Rate;
+ if(!(rate > 0.0f))
+ {
+ state->lfo_scale = 0.0f;
+ state->lfo_range = 1;
+ state->lfo_disp = 0;
+ }
+ else
+ {
+ /* Calculate LFO coefficient */
+ state->lfo_range = fastf2u(frequency/rate + 0.5f);
+ switch(state->waveform)
+ {
+ case AL_CHORUS_WAVEFORM_TRIANGLE:
+ state->lfo_scale = 4.0f / state->lfo_range;
+ break;
+ case AL_CHORUS_WAVEFORM_SINUSOID:
+ state->lfo_scale = F_2PI / state->lfo_range;
+ break;
+ }
+
+ /* Calculate lfo phase displacement */
+ state->lfo_disp = fastf2i(state->lfo_range * (phase/360.0f));
+ }
+}
+
+static inline void Triangle(ALint *delay_left, ALint *delay_right, ALuint offset, const ALchorusState *state)
+{
+ ALfloat lfo_value;
+
+ lfo_value = 2.0f - fabsf(2.0f - state->lfo_scale*(offset%state->lfo_range));
+ lfo_value *= state->depth * state->delay;
+ *delay_left = fastf2i(lfo_value) + state->delay;
+
+ offset += state->lfo_disp;
+ lfo_value = 2.0f - fabsf(2.0f - state->lfo_scale*(offset%state->lfo_range));
+ lfo_value *= state->depth * state->delay;
+ *delay_right = fastf2i(lfo_value) + state->delay;
+}
+
+static inline void Sinusoid(ALint *delay_left, ALint *delay_right, ALuint offset, const ALchorusState *state)
+{
+ ALfloat lfo_value;
+
+ lfo_value = 1.0f + sinf(state->lfo_scale*(offset%state->lfo_range));
+ lfo_value *= state->depth * state->delay;
+ *delay_left = fastf2i(lfo_value) + state->delay;
+
+ offset += state->lfo_disp;
+ lfo_value = 1.0f + sinf(state->lfo_scale*(offset%state->lfo_range));
+ lfo_value *= state->depth * state->delay;
+ *delay_right = fastf2i(lfo_value) + state->delay;
+}
+
+#define DECL_TEMPLATE(Func) \
+static void Process##Func(ALchorusState *state, const ALuint SamplesToDo, \
+ const ALfloat *restrict SamplesIn, ALfloat (*restrict out)[2]) \
+{ \
+ const ALuint bufmask = state->BufferLength-1; \
+ ALfloat *restrict leftbuf = state->SampleBuffer[0]; \
+ ALfloat *restrict rightbuf = state->SampleBuffer[1]; \
+ ALuint offset = state->offset; \
+ const ALfloat feedback = state->feedback; \
+ ALuint it; \
+ \
+ for(it = 0;it < SamplesToDo;it++) \
+ { \
+ ALint delay_left, delay_right; \
+ Func(&delay_left, &delay_right, offset, state); \
+ \
+ out[it][0] = leftbuf[(offset-delay_left)&bufmask]; \
+ leftbuf[offset&bufmask] = (out[it][0]+SamplesIn[it]) * feedback; \
+ \
+ out[it][1] = rightbuf[(offset-delay_right)&bufmask]; \
+ rightbuf[offset&bufmask] = (out[it][1]+SamplesIn[it]) * feedback; \
+ \
+ offset++; \
+ } \
+ state->offset = offset; \
+}
+
+DECL_TEMPLATE(Triangle)
+DECL_TEMPLATE(Sinusoid)
+
+#undef DECL_TEMPLATE
+
+static ALvoid ALchorusState_process(ALchorusState *state, ALuint SamplesToDo, const ALfloat *restrict SamplesIn, ALfloat (*restrict SamplesOut)[BUFFERSIZE])
+{
+ ALuint it, kt;
+ ALuint base;
+
+ for(base = 0;base < SamplesToDo;)
+ {
+ ALfloat temps[64][2];
+ ALuint td = minu(SamplesToDo-base, 64);
+
+ if(state->waveform == AL_CHORUS_WAVEFORM_TRIANGLE)
+ ProcessTriangle(state, td, SamplesIn+base, temps);
+ else if(state->waveform == AL_CHORUS_WAVEFORM_SINUSOID)
+ ProcessSinusoid(state, td, SamplesIn+base, temps);
+
+ for(kt = 0;kt < MaxChannels;kt++)
+ {
+ ALfloat gain = state->Gain[0][kt];
+ if(gain > GAIN_SILENCE_THRESHOLD)
+ {
+ for(it = 0;it < td;it++)
+ SamplesOut[kt][it+base] += temps[it][0] * gain;
+ }
+
+ gain = state->Gain[1][kt];
+ if(gain > GAIN_SILENCE_THRESHOLD)
+ {
+ for(it = 0;it < td;it++)
+ SamplesOut[kt][it+base] += temps[it][1] * gain;
+ }
+ }
+
+ base += td;
+ }
+}
+
+static void ALchorusState_Delete(ALchorusState *state)
+{
+ free(state);
+}
+
+DEFINE_ALEFFECTSTATE_VTABLE(ALchorusState);
+
+
+typedef struct ALchorusStateFactory {
+ DERIVE_FROM_TYPE(ALeffectStateFactory);
+} ALchorusStateFactory;
+
+static ALeffectState *ALchorusStateFactory_create(ALchorusStateFactory *UNUSED(factory))
+{
+ ALchorusState *state;
+
+ state = malloc(sizeof(*state));
+ if(!state) return NULL;
+ SET_VTABLE2(ALchorusState, ALeffectState, state);
+
+ state->BufferLength = 0;
+ state->SampleBuffer[0] = NULL;
+ state->SampleBuffer[1] = NULL;
+ state->offset = 0;
+ state->lfo_range = 1;
+
+ return STATIC_CAST(ALeffectState, state);
+}
+
+DEFINE_ALEFFECTSTATEFACTORY_VTABLE(ALchorusStateFactory);
+
+
+ALeffectStateFactory *ALchorusStateFactory_getFactory(void)
+{
+ static ALchorusStateFactory ChorusFactory = { { GET_VTABLE2(ALchorusStateFactory, ALeffectStateFactory) } };
+
+ return STATIC_CAST(ALeffectStateFactory, &ChorusFactory);
+}
+
+
+void ALchorus_setParami(ALeffect *effect, ALCcontext *context, ALenum param, ALint val)
+{
+ ALeffectProps *props = &effect->Props;
+ switch(param)
+ {
+ case AL_CHORUS_WAVEFORM:
+ if(!(val >= AL_CHORUS_MIN_WAVEFORM && val <= AL_CHORUS_MAX_WAVEFORM))
+ SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
+ props->Chorus.Waveform = val;
+ break;
+
+ case AL_CHORUS_PHASE:
+ if(!(val >= AL_CHORUS_MIN_PHASE && val <= AL_CHORUS_MAX_PHASE))
+ SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
+ props->Chorus.Phase = val;
+ break;
+
+ default:
+ SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
+ }
+}
+void ALchorus_setParamiv(ALeffect *effect, ALCcontext *context, ALenum param, const ALint *vals)
+{
+ ALchorus_setParami(effect, context, param, vals[0]);
+}
+void ALchorus_setParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val)
+{
+ ALeffectProps *props = &effect->Props;
+ switch(param)
+ {
+ case AL_CHORUS_RATE:
+ if(!(val >= AL_CHORUS_MIN_RATE && val <= AL_CHORUS_MAX_RATE))
+ SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
+ props->Chorus.Rate = val;
+ break;
+
+ case AL_CHORUS_DEPTH:
+ if(!(val >= AL_CHORUS_MIN_DEPTH && val <= AL_CHORUS_MAX_DEPTH))
+ SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
+ props->Chorus.Depth = val;
+ break;
+
+ case AL_CHORUS_FEEDBACK:
+ if(!(val >= AL_CHORUS_MIN_FEEDBACK && val <= AL_CHORUS_MAX_FEEDBACK))
+ SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
+ props->Chorus.Feedback = val;
+ break;
+
+ case AL_CHORUS_DELAY:
+ if(!(val >= AL_CHORUS_MIN_DELAY && val <= AL_CHORUS_MAX_DELAY))
+ SET_ERROR_AND_RETURN(context, AL_INVALID_VALUE);
+ props->Chorus.Delay = val;
+ break;
+
+ default:
+ SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
+ }
+}
+void ALchorus_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals)
+{
+ ALchorus_setParamf(effect, context, param, vals[0]);
+}
+
+void ALchorus_getParami(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *val)
+{
+ const ALeffectProps *props = &effect->Props;
+ switch(param)
+ {
+ case AL_CHORUS_WAVEFORM:
+ *val = props->Chorus.Waveform;
+ break;
+
+ case AL_CHORUS_PHASE:
+ *val = props->Chorus.Phase;
+ break;
+
+ default:
+ SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
+ }
+}
+void ALchorus_getParamiv(const ALeffect *effect, ALCcontext *context, ALenum param, ALint *vals)
+{
+ ALchorus_getParami(effect, context, param, vals);
+}
+void ALchorus_getParamf(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val)
+{
+ const ALeffectProps *props = &effect->Props;
+ switch(param)
+ {
+ case AL_CHORUS_RATE:
+ *val = props->Chorus.Rate;
+ break;
+
+ case AL_CHORUS_DEPTH:
+ *val = props->Chorus.Depth;
+ break;
+
+ case AL_CHORUS_FEEDBACK:
+ *val = props->Chorus.Feedback;
+ break;
+
+ case AL_CHORUS_DELAY:
+ *val = props->Chorus.Delay;
+ break;
+
+ default:
+ SET_ERROR_AND_RETURN(context, AL_INVALID_ENUM);
+ }
+}
+void ALchorus_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals)
+{
+ ALchorus_getParamf(effect, context, param, vals);
+}
+
+DEFINE_ALEFFECT_VTABLE(ALchorus);