1 files changed, 332 insertions, 0 deletions
diff --git a/alc/effects/fshifter.cpp b/alc/effects/fshifter.cpp
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--- /dev/null
+++ b/alc/effects/fshifter.cpp
@@ -0,0 +1,332 @@
+/**
+ * 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 <cmath>
+#include <cstdlib>
+#include <array>
+#include <complex>
+#include <algorithm>
+
+#include "al/auxeffectslot.h"
+#include "alcmain.h"
+#include "alcontext.h"
+#include "alu.h"
+
+#include "alcomplex.h"
+
+namespace {
+
+using complex_d = std::complex<double>;
+
+#define HIL_SIZE 1024
+#define OVERSAMP (1<<2)
+
+#define HIL_STEP     (HIL_SIZE / OVERSAMP)
+#define FIFO_LATENCY (HIL_STEP * (OVERSAMP-1))
+
+/* Define a Hann window, used to filter the HIL input and output. */
+/* Making this constexpr seems to require C++14. */
+std::array<ALdouble,HIL_SIZE> InitHannWindow()
+{
+    std::array<ALdouble,HIL_SIZE> ret;
+    /* Create lookup table of the Hann window for the desired size, i.e. HIL_SIZE */
+    for(size_t i{0};i < HIL_SIZE>>1;i++)
+    {
+        constexpr double scale{al::MathDefs<double>::Pi() / double{HIL_SIZE-1}};
+        const double val{std::sin(static_cast<double>(i) * scale)};
+        ret[i] = ret[HIL_SIZE-1-i] = val * val;
+    }
+    return ret;
+}
+alignas(16) const std::array<ALdouble,HIL_SIZE> HannWindow = InitHannWindow();
+
+
+struct FshifterState final : public EffectState {
+    /* Effect parameters */
+    size_t   mCount{};
+    ALsizei  mPhaseStep[2]{};
+    ALsizei  mPhase[2]{};
+    ALdouble mSign[2]{};
+
+
+    /*Effects buffers*/ 
+    ALfloat   mInFIFO[HIL_SIZE]{};
+    complex_d mOutFIFO[HIL_SIZE]{};
+    complex_d mOutputAccum[HIL_SIZE]{};
+    complex_d mAnalytic[HIL_SIZE]{};
+    complex_d mOutdata[BUFFERSIZE]{};
+
+    alignas(16) ALfloat mBufferOut[BUFFERSIZE]{};
+
+    /* Effect gains for each output channel */
+    struct {
+        ALfloat Current[MAX_OUTPUT_CHANNELS]{};
+        ALfloat Target[MAX_OUTPUT_CHANNELS]{};
+    } mGains[2];
+
+
+    ALboolean deviceUpdate(const ALCdevice *device) override;
+    void update(const ALCcontext *context, const ALeffectslot *slot, const EffectProps *props, const EffectTarget target) override;
+    void process(const size_t samplesToDo, const al::span<const FloatBufferLine> samplesIn, const al::span<FloatBufferLine> samplesOut) override;
+
+    DEF_NEWDEL(FshifterState)
+};
+
+ALboolean FshifterState::deviceUpdate(const ALCdevice*)
+{
+    /* (Re-)initializing parameters and clear the buffers. */
+    mCount = FIFO_LATENCY;
+
+    std::fill(std::begin(mPhaseStep),   std::end(mPhaseStep),   0);
+    std::fill(std::begin(mPhase),       std::end(mPhase),       0);
+    std::fill(std::begin(mSign),        std::end(mSign),        1.0);
+    std::fill(std::begin(mInFIFO),      std::end(mInFIFO),      0.0f);
+    std::fill(std::begin(mOutFIFO),     std::end(mOutFIFO),     complex_d{});
+    std::fill(std::begin(mOutputAccum), std::end(mOutputAccum), complex_d{});
+    std::fill(std::begin(mAnalytic),    std::end(mAnalytic),    complex_d{});
+
+    for(auto &gain : mGains)
+    {
+        std::fill(std::begin(gain.Current), std::end(gain.Current), 0.0f);
+        std::fill(std::begin(gain.Target), std::end(gain.Target), 0.0f);
+    }
+
+    return AL_TRUE;
+}
+
+void FshifterState::update(const ALCcontext *context, const ALeffectslot *slot, const EffectProps *props, const EffectTarget target)
+{
+    const ALCdevice *device{context->mDevice.get()};
+
+    ALfloat step{props->Fshifter.Frequency / static_cast<ALfloat>(device->Frequency)};
+    mPhaseStep[0] = mPhaseStep[1] = fastf2i(minf(step, 0.5f) * FRACTIONONE);
+
+    switch(props->Fshifter.LeftDirection)
+    {
+    case AL_FREQUENCY_SHIFTER_DIRECTION_DOWN:
+        mSign[0] = -1.0;
+        break;
+
+    case AL_FREQUENCY_SHIFTER_DIRECTION_UP:
+        mSign[0] = 1.0;
+        break;
+
+    case AL_FREQUENCY_SHIFTER_DIRECTION_OFF:
+        mPhase[0]     = 0;
+        mPhaseStep[0] = 0;
+        break;
+    }
+
+    switch (props->Fshifter.RightDirection)
+    {
+    case AL_FREQUENCY_SHIFTER_DIRECTION_DOWN:
+        mSign[1] = -1.0;
+        break;
+
+    case AL_FREQUENCY_SHIFTER_DIRECTION_UP:
+        mSign[1] = 1.0;
+        break;
+
+    case AL_FREQUENCY_SHIFTER_DIRECTION_OFF:
+        mPhase[1]     = 0;
+        mPhaseStep[1] = 0;
+        break;
+    }
+
+    ALfloat coeffs[2][MAX_AMBI_CHANNELS];
+    CalcDirectionCoeffs({-1.0f, 0.0f, -1.0f}, 0.0f, coeffs[0]);
+    CalcDirectionCoeffs({ 1.0f, 0.0f, -1.0f}, 0.0f, coeffs[1]);
+
+    mOutTarget = target.Main->Buffer;
+    ComputePanGains(target.Main, coeffs[0], slot->Params.Gain, mGains[0].Target);
+    ComputePanGains(target.Main, coeffs[1], slot->Params.Gain, mGains[1].Target);
+}
+
+void FshifterState::process(const size_t samplesToDo, const al::span<const FloatBufferLine> samplesIn, const al::span<FloatBufferLine> samplesOut)
+{
+    static constexpr complex_d complex_zero{0.0, 0.0};
+    ALfloat *RESTRICT BufferOut = mBufferOut;
+    size_t j, k;
+
+    for(size_t base{0u};base < samplesToDo;)
+    {
+        const size_t todo{minz(HIL_SIZE-mCount, samplesToDo-base)};
+
+        ASSUME(todo > 0);
+
+        /* Fill FIFO buffer with samples data */
+        k = mCount;
+        for(j = 0;j < todo;j++,k++)
+        {
+            mInFIFO[k] = samplesIn[0][base+j];
+            mOutdata[base+j] = mOutFIFO[k-FIFO_LATENCY];
+        }
+        mCount += todo;
+        base += todo;
+
+        /* Check whether FIFO buffer is filled */
+        if(mCount < HIL_SIZE) continue;
+        mCount = FIFO_LATENCY;
+
+        /* Real signal windowing and store in Analytic buffer */
+        for(k = 0;k < HIL_SIZE;k++)
+        {
+            mAnalytic[k].real(mInFIFO[k] * HannWindow[k]);
+            mAnalytic[k].imag(0.0);
+        }
+
+        /* Processing signal by Discrete Hilbert Transform (analytical signal). */
+        complex_hilbert(mAnalytic);
+
+        /* Windowing and add to output accumulator */
+        for(k = 0;k < HIL_SIZE;k++)
+            mOutputAccum[k] += 2.0/OVERSAMP*HannWindow[k]*mAnalytic[k];
+
+        /* Shift accumulator, input & output FIFO */
+        for(k = 0;k < HIL_STEP;k++) mOutFIFO[k] = mOutputAccum[k];
+        for(j = 0;k < HIL_SIZE;k++,j++) mOutputAccum[j] = mOutputAccum[k];
+        for(;j < HIL_SIZE;j++) mOutputAccum[j] = complex_zero;
+        for(k = 0;k < FIFO_LATENCY;k++)
+            mInFIFO[k] = mInFIFO[k+HIL_STEP];
+    }
+
+    /* Process frequency shifter using the analytic signal obtained. */
+    for(ALsizei c{0};c < 2;++c)
+    {
+        for(k = 0;k < samplesToDo;++k)
+        {
+            double phase = mPhase[c] * ((1.0 / FRACTIONONE) * al::MathDefs<double>::Tau());
+            BufferOut[k] = static_cast<float>(mOutdata[k].real()*std::cos(phase) +
+                mOutdata[k].imag()*std::sin(phase)*mSign[c]);
+
+            mPhase[c] += mPhaseStep[c];
+            mPhase[c] &= FRACTIONMASK;
+        }
+
+        /* Now, mix the processed sound data to the output. */
+        MixSamples({BufferOut, samplesToDo}, samplesOut, mGains[c].Current, mGains[c].Target,
+            maxz(samplesToDo, 512), 0);
+    }
+}
+
+
+void Fshifter_setParamf(EffectProps *props, ALCcontext *context, ALenum param, ALfloat val)
+{
+    switch(param)
+    {
+        case AL_FREQUENCY_SHIFTER_FREQUENCY:
+            if(!(val >= AL_FREQUENCY_SHIFTER_MIN_FREQUENCY && val <= AL_FREQUENCY_SHIFTER_MAX_FREQUENCY))
+                SETERR_RETURN(context, AL_INVALID_VALUE,,"Frequency shifter frequency out of range");
+            props->Fshifter.Frequency = val;
+            break;
+
+        default:
+            context->setError(AL_INVALID_ENUM, "Invalid frequency shifter float property 0x%04x",
+                param);
+    }
+}
+void Fshifter_setParamfv(EffectProps *props, ALCcontext *context, ALenum param, const ALfloat *vals)
+{ Fshifter_setParamf(props, context, param, vals[0]); }
+
+void Fshifter_setParami(EffectProps *props, ALCcontext *context, ALenum param, ALint val)
+{
+    switch(param)
+    {
+        case AL_FREQUENCY_SHIFTER_LEFT_DIRECTION:
+            if(!(val >= AL_FREQUENCY_SHIFTER_MIN_LEFT_DIRECTION && val <= AL_FREQUENCY_SHIFTER_MAX_LEFT_DIRECTION))
+                SETERR_RETURN(context, AL_INVALID_VALUE,,"Frequency shifter left direction out of range");
+            props->Fshifter.LeftDirection = val;
+            break;
+
+        case AL_FREQUENCY_SHIFTER_RIGHT_DIRECTION:
+            if(!(val >= AL_FREQUENCY_SHIFTER_MIN_RIGHT_DIRECTION && val <= AL_FREQUENCY_SHIFTER_MAX_RIGHT_DIRECTION))
+                SETERR_RETURN(context, AL_INVALID_VALUE,,"Frequency shifter right direction out of range");
+            props->Fshifter.RightDirection = val;
+            break;
+
+        default:
+            context->setError(AL_INVALID_ENUM, "Invalid frequency shifter integer property 0x%04x",
+                param);
+    }
+}
+void Fshifter_setParamiv(EffectProps *props, ALCcontext *context, ALenum param, const ALint *vals)
+{ Fshifter_setParami(props, context, param, vals[0]); }
+
+void Fshifter_getParami(const EffectProps *props, ALCcontext *context, ALenum param, ALint *val)
+{
+    switch(param)
+    {
+        case AL_FREQUENCY_SHIFTER_LEFT_DIRECTION:
+            *val = props->Fshifter.LeftDirection;
+            break;
+        case AL_FREQUENCY_SHIFTER_RIGHT_DIRECTION:
+            *val = props->Fshifter.RightDirection;
+            break;
+        default:
+            context->setError(AL_INVALID_ENUM, "Invalid frequency shifter integer property 0x%04x",
+                param);
+    }
+}
+void Fshifter_getParamiv(const EffectProps *props, ALCcontext *context, ALenum param, ALint *vals)
+{ Fshifter_getParami(props, context, param, vals); }
+
+void Fshifter_getParamf(const EffectProps *props, ALCcontext *context, ALenum param, ALfloat *val)
+{
+    switch(param)
+    {
+        case AL_FREQUENCY_SHIFTER_FREQUENCY:
+            *val = props->Fshifter.Frequency;
+            break;
+
+        default:
+            context->setError(AL_INVALID_ENUM, "Invalid frequency shifter float property 0x%04x",
+                param);
+    }
+}
+void Fshifter_getParamfv(const EffectProps *props, ALCcontext *context, ALenum param, ALfloat *vals)
+{ Fshifter_getParamf(props, context, param, vals); }
+
+DEFINE_ALEFFECT_VTABLE(Fshifter);
+
+
+struct FshifterStateFactory final : public EffectStateFactory {
+    EffectState *create() override { return new FshifterState{}; }
+    EffectProps getDefaultProps() const noexcept override;
+    const EffectVtable *getEffectVtable() const noexcept override { return &Fshifter_vtable; }
+};
+
+EffectProps FshifterStateFactory::getDefaultProps() const noexcept
+{
+    EffectProps props{};
+    props.Fshifter.Frequency      = AL_FREQUENCY_SHIFTER_DEFAULT_FREQUENCY;
+    props.Fshifter.LeftDirection  = AL_FREQUENCY_SHIFTER_DEFAULT_LEFT_DIRECTION;
+    props.Fshifter.RightDirection = AL_FREQUENCY_SHIFTER_DEFAULT_RIGHT_DIRECTION;
+    return props;
+}
+
+} // namespace
+
+EffectStateFactory *FshifterStateFactory_getFactory()
+{
+    static FshifterStateFactory FshifterFactory{};
+    return &FshifterFactory;
+}