update openal-soft

sync point: master-ac5d40e40a0155351fe1be4aab30017b6a13a859

Engine/lib/openal-soft/Alc/effects/chorus.cpp

@@ -0,0 +1,287 @@
+/**
+ * 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.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ * Or go to http://www.gnu.org/copyleft/lgpl.html
+ */
+
+#include "config.h"
+
+#include <algorithm>
+#include <climits>
+#include <cmath>
+#include <cstdlib>
+#include <iterator>
+
+#include "alcmain.h"
+#include "alcontext.h"
+#include "almalloc.h"
+#include "alnumeric.h"
+#include "alspan.h"
+#include "alu.h"
+#include "core/ambidefs.h"
+#include "effects/base.h"
+#include "effectslot.h"
+#include "math_defs.h"
+#include "opthelpers.h"
+#include "vector.h"
+
+
+namespace {
+
+#define MAX_UPDATE_SAMPLES 256
+
+struct ChorusState final : public EffectState {
+    al::vector<float,16> mSampleBuffer;
+    uint mOffset{0};
+
+    uint mLfoOffset{0};
+    uint mLfoRange{1};
+    float mLfoScale{0.0f};
+    uint mLfoDisp{0};
+
+    /* Gains for left and right sides */
+    struct {
+        float Current[MAX_OUTPUT_CHANNELS]{};
+        float Target[MAX_OUTPUT_CHANNELS]{};
+    } mGains[2];
+
+    /* effect parameters */
+    ChorusWaveform mWaveform{};
+    int mDelay{0};
+    float mDepth{0.0f};
+    float mFeedback{0.0f};
+
+    void getTriangleDelays(uint (*delays)[MAX_UPDATE_SAMPLES], const size_t todo);
+    void getSinusoidDelays(uint (*delays)[MAX_UPDATE_SAMPLES], const size_t todo);
+
+    void deviceUpdate(const ALCdevice *device, const Buffer &buffer) override;
+    void update(const ALCcontext *context, const EffectSlot *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(ChorusState)
+};
+
+void ChorusState::deviceUpdate(const ALCdevice *Device, const Buffer&)
+{
+    constexpr float max_delay{maxf(AL_CHORUS_MAX_DELAY, AL_FLANGER_MAX_DELAY)};
+
+    const auto frequency = static_cast<float>(Device->Frequency);
+    const size_t maxlen{NextPowerOf2(float2uint(max_delay*2.0f*frequency) + 1u)};
+    if(maxlen != mSampleBuffer.size())
+        al::vector<float,16>(maxlen).swap(mSampleBuffer);
+
+    std::fill(mSampleBuffer.begin(), mSampleBuffer.end(), 0.0f);
+    for(auto &e : mGains)
+    {
+        std::fill(std::begin(e.Current), std::end(e.Current), 0.0f);
+        std::fill(std::begin(e.Target), std::end(e.Target), 0.0f);
+    }
+}
+
+void ChorusState::update(const ALCcontext *Context, const EffectSlot *Slot,
+    const EffectProps *props, const EffectTarget target)
+{
+    constexpr int mindelay{(MaxResamplerPadding>>1) << MixerFracBits};
+
+    /* The LFO depth is scaled to be relative to the sample delay. Clamp the
+     * delay and depth to allow enough padding for resampling.
+     */
+    const ALCdevice *device{Context->mDevice.get()};
+    const auto frequency = static_cast<float>(device->Frequency);
+
+    mWaveform = props->Chorus.Waveform;
+
+    mDelay = maxi(float2int(props->Chorus.Delay*frequency*MixerFracOne + 0.5f), mindelay);
+    mDepth = minf(props->Chorus.Depth * static_cast<float>(mDelay),
+        static_cast<float>(mDelay - mindelay));
+
+    mFeedback = props->Chorus.Feedback;
+
+    /* Gains for left and right sides */
+    const auto lcoeffs = CalcDirectionCoeffs({-1.0f, 0.0f, 0.0f}, 0.0f);
+    const auto rcoeffs = CalcDirectionCoeffs({ 1.0f, 0.0f, 0.0f}, 0.0f);
+
+    mOutTarget = target.Main->Buffer;
+    ComputePanGains(target.Main, lcoeffs.data(), Slot->Gain, mGains[0].Target);
+    ComputePanGains(target.Main, rcoeffs.data(), Slot->Gain, mGains[1].Target);
+
+    float rate{props->Chorus.Rate};
+    if(!(rate > 0.0f))
+    {
+        mLfoOffset = 0;
+        mLfoRange = 1;
+        mLfoScale = 0.0f;
+        mLfoDisp = 0;
+    }
+    else
+    {
+        /* Calculate LFO coefficient (number of samples per cycle). Limit the
+         * max range to avoid overflow when calculating the displacement.
+         */
+        uint lfo_range{float2uint(minf(frequency/rate + 0.5f, float{INT_MAX/360 - 180}))};
+
+        mLfoOffset = mLfoOffset * lfo_range / mLfoRange;
+        mLfoRange = lfo_range;
+        switch(mWaveform)
+        {
+        case ChorusWaveform::Triangle:
+            mLfoScale = 4.0f / static_cast<float>(mLfoRange);
+            break;
+        case ChorusWaveform::Sinusoid:
+            mLfoScale = al::MathDefs<float>::Tau() / static_cast<float>(mLfoRange);
+            break;
+        }
+
+        /* Calculate lfo phase displacement */
+        int phase{props->Chorus.Phase};
+        if(phase < 0) phase = 360 + phase;
+        mLfoDisp = (mLfoRange*static_cast<uint>(phase) + 180) / 360;
+    }
+}
+
+
+void ChorusState::getTriangleDelays(uint (*delays)[MAX_UPDATE_SAMPLES], const size_t todo)
+{
+    const uint lfo_range{mLfoRange};
+    const float lfo_scale{mLfoScale};
+    const float depth{mDepth};
+    const int delay{mDelay};
+
+    ASSUME(lfo_range > 0);
+    ASSUME(todo > 0);
+
+    uint offset{mLfoOffset};
+    auto gen_lfo = [&offset,lfo_range,lfo_scale,depth,delay]() -> uint
+    {
+        offset = (offset+1)%lfo_range;
+        const float offset_norm{static_cast<float>(offset) * lfo_scale};
+        return static_cast<uint>(fastf2i((1.0f-std::abs(2.0f-offset_norm)) * depth) + delay);
+    };
+    std::generate_n(delays[0], todo, gen_lfo);
+
+    offset = (mLfoOffset+mLfoDisp) % lfo_range;
+    std::generate_n(delays[1], todo, gen_lfo);
+
+    mLfoOffset = static_cast<uint>(mLfoOffset+todo) % lfo_range;
+}
+
+void ChorusState::getSinusoidDelays(uint (*delays)[MAX_UPDATE_SAMPLES], const size_t todo)
+{
+    const uint lfo_range{mLfoRange};
+    const float lfo_scale{mLfoScale};
+    const float depth{mDepth};
+    const int delay{mDelay};
+
+    ASSUME(lfo_range > 0);
+    ASSUME(todo > 0);
+
+    uint offset{mLfoOffset};
+    auto gen_lfo = [&offset,lfo_range,lfo_scale,depth,delay]() -> uint
+    {
+        offset = (offset+1)%lfo_range;
+        const float offset_norm{static_cast<float>(offset) * lfo_scale};
+        return static_cast<uint>(fastf2i(std::sin(offset_norm)*depth) + delay);
+    };
+    std::generate_n(delays[0], todo, gen_lfo);
+
+    offset = (mLfoOffset+mLfoDisp) % lfo_range;
+    std::generate_n(delays[1], todo, gen_lfo);
+
+    mLfoOffset = static_cast<uint>(mLfoOffset+todo) % lfo_range;
+}
+
+void ChorusState::process(const size_t samplesToDo, const al::span<const FloatBufferLine> samplesIn, const al::span<FloatBufferLine> samplesOut)
+{
+    const size_t bufmask{mSampleBuffer.size()-1};
+    const float feedback{mFeedback};
+    const uint avgdelay{(static_cast<uint>(mDelay) + (MixerFracOne>>1)) >> MixerFracBits};
+    float *RESTRICT delaybuf{mSampleBuffer.data()};
+    uint offset{mOffset};
+
+    for(size_t base{0u};base < samplesToDo;)
+    {
+        const size_t todo{minz(MAX_UPDATE_SAMPLES, samplesToDo-base)};
+
+        uint moddelays[2][MAX_UPDATE_SAMPLES];
+        if(mWaveform == ChorusWaveform::Sinusoid)
+            getSinusoidDelays(moddelays, todo);
+        else /*if(mWaveform == ChorusWaveform::Triangle)*/
+            getTriangleDelays(moddelays, todo);
+
+        alignas(16) float temps[2][MAX_UPDATE_SAMPLES];
+        for(size_t i{0u};i < todo;++i)
+        {
+            // Feed the buffer's input first (necessary for delays < 1).
+            delaybuf[offset&bufmask] = samplesIn[0][base+i];
+
+            // Tap for the left output.
+            uint delay{offset - (moddelays[0][i]>>MixerFracBits)};
+            float mu{static_cast<float>(moddelays[0][i]&MixerFracMask) * (1.0f/MixerFracOne)};
+            temps[0][i] = cubic(delaybuf[(delay+1) & bufmask], delaybuf[(delay  ) & bufmask],
+                delaybuf[(delay-1) & bufmask], delaybuf[(delay-2) & bufmask], mu);
+
+            // Tap for the right output.
+            delay = offset - (moddelays[1][i]>>MixerFracBits);
+            mu = static_cast<float>(moddelays[1][i]&MixerFracMask) * (1.0f/MixerFracOne);
+            temps[1][i] = cubic(delaybuf[(delay+1) & bufmask], delaybuf[(delay  ) & bufmask],
+                delaybuf[(delay-1) & bufmask], delaybuf[(delay-2) & bufmask], mu);
+
+            // Accumulate feedback from the average delay of the taps.
+            delaybuf[offset&bufmask] += delaybuf[(offset-avgdelay) & bufmask] * feedback;
+            ++offset;
+        }
+
+        for(ALsizei c{0};c < 2;++c)
+            MixSamples({temps[c], todo}, samplesOut, mGains[c].Current, mGains[c].Target,
+                samplesToDo-base, base);
+
+        base += todo;
+    }
+
+    mOffset = offset;
+}
+
+
+struct ChorusStateFactory final : public EffectStateFactory {
+    al::intrusive_ptr<EffectState> create() override
+    { return al::intrusive_ptr<EffectState>{new ChorusState{}}; }
+};
+
+
+/* Flanger is basically a chorus with a really short delay. They can both use
+ * the same processing functions, so piggyback flanger on the chorus functions.
+ */
+struct FlangerStateFactory final : public EffectStateFactory {
+    al::intrusive_ptr<EffectState> create() override
+    { return al::intrusive_ptr<EffectState>{new ChorusState{}}; }
+};
+
+} // namespace
+
+EffectStateFactory *ChorusStateFactory_getFactory()
+{
+    static ChorusStateFactory ChorusFactory{};
+    return &ChorusFactory;
+}
+
+EffectStateFactory *FlangerStateFactory_getFactory()
+{
+    static FlangerStateFactory FlangerFactory{};
+    return &FlangerFactory;
+}