1 files changed, 326 insertions, 0 deletions
diff --git a/Alc/effects/autowah.cpp b/Alc/effects/autowah.cpp
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+++ b/Alc/effects/autowah.cpp
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+/**
+ * OpenAL cross platform audio library
+ * Copyright (C) 2018 by Raul Herraiz.
+ * 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.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ * Or go to http://www.gnu.org/copyleft/lgpl.html
+ */
+
+#include "config.h"
+
+#include <math.h>
+#include <stdlib.h>
+
+#include "alMain.h"
+#include "alAuxEffectSlot.h"
+#include "alError.h"
+#include "alu.h"
+#include "filters/defs.h"
+
+#define MIN_FREQ 20.0f
+#define MAX_FREQ 2500.0f
+#define Q_FACTOR 5.0f
+
+struct ALautowahState final : public ALeffectState {
+    /* Effect parameters */
+    ALfloat AttackRate;
+    ALfloat ReleaseRate;
+    ALfloat ResonanceGain;
+    ALfloat PeakGain;
+    ALfloat FreqMinNorm;
+    ALfloat BandwidthNorm;
+    ALfloat env_delay;
+
+    /* Filter components derived from the envelope. */
+    struct {
+        ALfloat cos_w0;
+        ALfloat alpha;
+    } Env[BUFFERSIZE];
+
+    struct {
+        /* Effect filters' history. */
+        struct {
+            ALfloat z1, z2;
+        } Filter;
+
+        /* Effect gains for each output channel */
+        ALfloat CurrentGains[MAX_OUTPUT_CHANNELS];
+        ALfloat TargetGains[MAX_OUTPUT_CHANNELS];
+    } Chans[MAX_EFFECT_CHANNELS];
+
+    /* Effects buffers */
+    alignas(16) ALfloat BufferOut[BUFFERSIZE];
+};
+
+static ALvoid ALautowahState_Destruct(ALautowahState *state);
+static ALboolean ALautowahState_deviceUpdate(ALautowahState *state, ALCdevice *device);
+static ALvoid ALautowahState_update(ALautowahState *state, const ALCcontext *context, const ALeffectslot *slot, const ALeffectProps *props);
+static ALvoid ALautowahState_process(ALautowahState *state, ALsizei SamplesToDo, const ALfloat (*RESTRICT SamplesIn)[BUFFERSIZE], ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE], ALsizei NumChannels);
+DECLARE_DEFAULT_ALLOCATORS(ALautowahState)
+
+DEFINE_ALEFFECTSTATE_VTABLE(ALautowahState);
+
+static void ALautowahState_Construct(ALautowahState *state)
+{
+    new (state) ALautowahState{};
+    ALeffectState_Construct(STATIC_CAST(ALeffectState, state));
+    SET_VTABLE2(ALautowahState, ALeffectState, state);
+}
+
+static ALvoid ALautowahState_Destruct(ALautowahState *state)
+{
+    ALeffectState_Destruct(STATIC_CAST(ALeffectState,state));
+    state->~ALautowahState();
+}
+
+static ALboolean ALautowahState_deviceUpdate(ALautowahState *state, ALCdevice *UNUSED(device))
+{
+    /* (Re-)initializing parameters and clear the buffers. */
+    ALsizei i, j;
+
+    state->AttackRate    = 1.0f;
+    state->ReleaseRate   = 1.0f;
+    state->ResonanceGain = 10.0f;
+    state->PeakGain      = 4.5f;
+    state->FreqMinNorm   = 4.5e-4f;
+    state->BandwidthNorm = 0.05f;
+    state->env_delay     = 0.0f;
+
+    memset(state->Env, 0, sizeof(state->Env));
+
+    for(i = 0;i < MAX_EFFECT_CHANNELS;i++)
+    {
+        for(j = 0;j < MAX_OUTPUT_CHANNELS;j++)
+            state->Chans[i].CurrentGains[j] = 0.0f;
+        state->Chans[i].Filter.z1 = 0.0f;
+        state->Chans[i].Filter.z2 = 0.0f;
+    }
+
+    return AL_TRUE;
+}
+
+static ALvoid ALautowahState_update(ALautowahState *state, const ALCcontext *context, const ALeffectslot *slot, const ALeffectProps *props)
+{
+    const ALCdevice *device = context->Device;
+    ALfloat ReleaseTime;
+    ALsizei i;
+
+    ReleaseTime = clampf(props->Autowah.ReleaseTime, 0.001f, 1.0f);
+
+    state->AttackRate    = expf(-1.0f / (props->Autowah.AttackTime*device->Frequency));
+    state->ReleaseRate   = expf(-1.0f / (ReleaseTime*device->Frequency));
+    /* 0-20dB Resonance Peak gain */
+    state->ResonanceGain = sqrtf(log10f(props->Autowah.Resonance)*10.0f / 3.0f);
+    state->PeakGain      = 1.0f - log10f(props->Autowah.PeakGain/AL_AUTOWAH_MAX_PEAK_GAIN);
+    state->FreqMinNorm   = MIN_FREQ / device->Frequency;
+    state->BandwidthNorm = (MAX_FREQ-MIN_FREQ) / device->Frequency;
+
+    STATIC_CAST(ALeffectState,state)->OutBuffer = device->FOAOut.Buffer;
+    STATIC_CAST(ALeffectState,state)->OutChannels = device->FOAOut.NumChannels;
+    for(i = 0;i < MAX_EFFECT_CHANNELS;i++)
+        ComputePanGains(&device->FOAOut, IdentityMatrixf.m[i], slot->Params.Gain,
+                        state->Chans[i].TargetGains);
+}
+
+static ALvoid ALautowahState_process(ALautowahState *state, ALsizei SamplesToDo, const ALfloat (*RESTRICT SamplesIn)[BUFFERSIZE], ALfloat (*RESTRICT SamplesOut)[BUFFERSIZE], ALsizei NumChannels)
+{
+    const ALfloat attack_rate = state->AttackRate;
+    const ALfloat release_rate = state->ReleaseRate;
+    const ALfloat res_gain = state->ResonanceGain;
+    const ALfloat peak_gain = state->PeakGain;
+    const ALfloat freq_min = state->FreqMinNorm;
+    const ALfloat bandwidth = state->BandwidthNorm;
+    ALfloat env_delay;
+    ALsizei c, i;
+
+    env_delay = state->env_delay;
+    for(i = 0;i < SamplesToDo;i++)
+    {
+        ALfloat w0, sample, a;
+
+        /* Envelope follower described on the book: Audio Effects, Theory,
+         * Implementation and Application.
+         */
+        sample = peak_gain * fabsf(SamplesIn[0][i]);
+        a = (sample > env_delay) ? attack_rate : release_rate;
+        env_delay = lerp(sample, env_delay, a);
+
+        /* Calculate the cos and alpha components for this sample's filter. */
+        w0 = minf((bandwidth*env_delay + freq_min), 0.46f) * F_TAU;
+        state->Env[i].cos_w0 = cosf(w0);
+        state->Env[i].alpha = sinf(w0)/(2.0f * Q_FACTOR);
+    }
+    state->env_delay = env_delay;
+
+    for(c = 0;c < MAX_EFFECT_CHANNELS; c++)
+    {
+        /* This effectively inlines BiquadFilter_setParams for a peaking
+         * filter and BiquadFilter_processC. The alpha and cosine components
+         * for the filter coefficients were previously calculated with the
+         * envelope. Because the filter changes for each sample, the
+         * coefficients are transient and don't need to be held.
+         */
+        ALfloat z1 = state->Chans[c].Filter.z1;
+        ALfloat z2 = state->Chans[c].Filter.z2;
+
+        for(i = 0;i < SamplesToDo;i++)
+        {
+            const ALfloat alpha = state->Env[i].alpha;
+            const ALfloat cos_w0 = state->Env[i].cos_w0;
+            ALfloat input, output;
+            ALfloat a[3], b[3];
+
+            b[0] =  1.0f + alpha*res_gain;
+            b[1] = -2.0f * cos_w0;
+            b[2] =  1.0f - alpha*res_gain;
+            a[0] =  1.0f + alpha/res_gain;
+            a[1] = -2.0f * cos_w0;
+            a[2] =  1.0f - alpha/res_gain;
+
+            input = SamplesIn[c][i];
+            output = input*(b[0]/a[0]) + z1;
+            z1 = input*(b[1]/a[0]) - output*(a[1]/a[0]) + z2;
+            z2 = input*(b[2]/a[0]) - output*(a[2]/a[0]);
+            state->BufferOut[i] = output;
+        }
+        state->Chans[c].Filter.z1 = z1;
+        state->Chans[c].Filter.z2 = z2;
+
+        /* Now, mix the processed sound data to the output. */
+        MixSamples(state->BufferOut, NumChannels, SamplesOut, state->Chans[c].CurrentGains,
+                   state->Chans[c].TargetGains, SamplesToDo, 0, SamplesToDo);
+    }
+}
+
+struct AutowahStateFactory final : public EffectStateFactory {
+    AutowahStateFactory() noexcept;
+};
+
+static ALeffectState *AutowahStateFactory_create(AutowahStateFactory *UNUSED(factory))
+{
+    ALautowahState *state;
+
+    NEW_OBJ0(state, ALautowahState)();
+    if(!state) return NULL;
+
+    return STATIC_CAST(ALeffectState, state);
+}
+
+DEFINE_EFFECTSTATEFACTORY_VTABLE(AutowahStateFactory);
+
+AutowahStateFactory::AutowahStateFactory() noexcept
+  : EffectStateFactory{GET_VTABLE2(AutowahStateFactory, EffectStateFactory)}
+{
+}
+
+EffectStateFactory *AutowahStateFactory_getFactory(void)
+{
+    static AutowahStateFactory AutowahFactory{};
+
+    return STATIC_CAST(EffectStateFactory, &AutowahFactory);
+}
+
+void ALautowah_setParamf(ALeffect *effect, ALCcontext *context, ALenum param, ALfloat val)
+{
+    ALeffectProps *props = &effect->Props;
+    switch(param)
+    {
+        case AL_AUTOWAH_ATTACK_TIME:
+            if(!(val >= AL_AUTOWAH_MIN_ATTACK_TIME && val <= AL_AUTOWAH_MAX_ATTACK_TIME))
+                SETERR_RETURN(context, AL_INVALID_VALUE,,"Autowah attack time out of range");
+            props->Autowah.AttackTime = val;
+            break;
+
+        case AL_AUTOWAH_RELEASE_TIME:
+            if(!(val >= AL_AUTOWAH_MIN_RELEASE_TIME && val <= AL_AUTOWAH_MAX_RELEASE_TIME))
+                SETERR_RETURN(context, AL_INVALID_VALUE,,"Autowah release time out of range");
+            props->Autowah.ReleaseTime = val;
+            break;
+
+        case AL_AUTOWAH_RESONANCE:
+            if(!(val >= AL_AUTOWAH_MIN_RESONANCE && val <= AL_AUTOWAH_MAX_RESONANCE))
+                SETERR_RETURN(context, AL_INVALID_VALUE,,"Autowah resonance out of range");
+            props->Autowah.Resonance = val;
+            break;
+
+        case AL_AUTOWAH_PEAK_GAIN:
+            if(!(val >= AL_AUTOWAH_MIN_PEAK_GAIN && val <= AL_AUTOWAH_MAX_PEAK_GAIN))
+                SETERR_RETURN(context, AL_INVALID_VALUE,,"Autowah peak gain out of range");
+            props->Autowah.PeakGain = val;
+            break;
+
+        default:
+            alSetError(context, AL_INVALID_ENUM, "Invalid autowah float property 0x%04x", param);
+    }
+}
+
+void ALautowah_setParamfv(ALeffect *effect, ALCcontext *context, ALenum param, const ALfloat *vals)
+{
+    ALautowah_setParamf(effect, context, param, vals[0]);
+}
+
+void ALautowah_setParami(ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint UNUSED(val))
+{
+    alSetError(context, AL_INVALID_ENUM, "Invalid autowah integer property 0x%04x", param);
+}
+
+void ALautowah_setParamiv(ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, const ALint *UNUSED(vals))
+{
+    alSetError(context, AL_INVALID_ENUM, "Invalid autowah integer vector property 0x%04x", param);
+}
+
+void ALautowah_getParami(const ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint *UNUSED(val))
+{
+    alSetError(context, AL_INVALID_ENUM, "Invalid autowah integer property 0x%04x", param);
+}
+void ALautowah_getParamiv(const ALeffect *UNUSED(effect), ALCcontext *context, ALenum param, ALint *UNUSED(vals))
+{
+    alSetError(context, AL_INVALID_ENUM, "Invalid autowah integer vector property 0x%04x", param);
+}
+
+void ALautowah_getParamf(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *val)
+{
+
+    const ALeffectProps *props = &effect->Props;
+    switch(param)
+    {
+        case AL_AUTOWAH_ATTACK_TIME:
+            *val = props->Autowah.AttackTime;
+            break;
+
+        case AL_AUTOWAH_RELEASE_TIME:
+            *val = props->Autowah.ReleaseTime;
+            break;
+
+        case AL_AUTOWAH_RESONANCE:
+            *val = props->Autowah.Resonance;
+            break;
+
+        case AL_AUTOWAH_PEAK_GAIN:
+            *val = props->Autowah.PeakGain;
+            break;
+
+        default:
+            alSetError(context, AL_INVALID_ENUM, "Invalid autowah float property 0x%04x", param);
+    }
+
+}
+
+void ALautowah_getParamfv(const ALeffect *effect, ALCcontext *context, ALenum param, ALfloat *vals)
+{
+    ALautowah_getParamf(effect, context, param, vals);
+}
+
+DEFINE_ALEFFECT_VTABLE(ALautowah);