openal-soft/OpenAL32/Include/alAuxEffectSlot.h

#ifndef _AL_AUXEFFECTSLOT_H_
#define _AL_AUXEFFECTSLOT_H_

#include "alMain.h"
#include "alEffect.h"

#include "almalloc.h"
#include "atomic.h"


struct ALeffectslot;

struct EffectTarget {
    MixParams *Main;
    MixParams *FOAOut;
    RealMixParams *RealOut;
};

struct EffectState {
    RefCount mRef{1u};

    ALfloat (*mOutBuffer)[BUFFERSIZE]{nullptr};
    ALsizei mOutChannels{0};


    virtual ~EffectState() = default;

    virtual ALboolean deviceUpdate(const ALCdevice *device) = 0;
    virtual void update(const ALCcontext *context, const ALeffectslot *slot, const ALeffectProps *props, const EffectTarget target) = 0;
    virtual void process(ALsizei samplesToDo, const ALfloat (*RESTRICT samplesIn)[BUFFERSIZE], ALfloat (*RESTRICT samplesOut)[BUFFERSIZE], ALsizei numChannels) = 0;

    void IncRef() noexcept;
    void DecRef() noexcept;
};


struct EffectStateFactory {
    virtual ~EffectStateFactory() { }

    virtual EffectState *create() = 0;
};


#define MAX_EFFECT_CHANNELS (4)


using ALeffectslotArray = al::FlexArray<ALeffectslot*>;


struct ALeffectslotProps {
    ALfloat   Gain;
    ALboolean AuxSendAuto;
    ALeffectslot *Target;

    ALenum Type;
    ALeffectProps Props;

    EffectState *State;

    std::atomic<ALeffectslotProps*> next;
};


struct ALeffectslot {
    ALfloat   Gain{1.0f};
    ALboolean AuxSendAuto{AL_TRUE};
    ALeffectslot *Target{nullptr};

    struct {
        ALenum Type{AL_EFFECT_NULL};
        ALeffectProps Props{};

        EffectState *State{nullptr};
    } Effect;

    std::atomic_flag PropsClean;

    RefCount ref{0u};

    std::atomic<ALeffectslotProps*> Update{nullptr};

    struct {
        ALfloat   Gain{1.0f};
        ALboolean AuxSendAuto{AL_TRUE};
        ALeffectslot *Target{nullptr};

        ALenum EffectType{AL_EFFECT_NULL};
        ALeffectProps EffectProps{};
        EffectState *mEffectState{nullptr};

        ALfloat RoomRolloff{0.0f}; /* Added to the source's room rolloff, not multiplied. */
        ALfloat DecayTime{0.0f};
        ALfloat DecayLFRatio{0.0f};
        ALfloat DecayHFRatio{0.0f};
        ALboolean DecayHFLimit{AL_FALSE};
        ALfloat AirAbsorptionGainHF{1.0f};
    } Params;

    /* Self ID */
    ALuint id{};

    ALsizei NumChannels{};
    BFChannelConfig ChanMap[MAX_EFFECT_CHANNELS];
    /* Wet buffer configuration is ACN channel order with N3D scaling:
     * * Channel 0 is the unattenuated mono signal.
     * * Channel 1 is OpenAL -X * sqrt(3)
     * * Channel 2 is OpenAL Y * sqrt(3)
     * * Channel 3 is OpenAL -Z * sqrt(3)
     * Consequently, effects that only want to work with mono input can use
     * channel 0 by itself. Effects that want multichannel can process the
     * ambisonics signal and make a B-Format source pan for first-order device
     * output (FOAOut).
     */
    alignas(16) ALfloat WetBuffer[MAX_EFFECT_CHANNELS][BUFFERSIZE];

    ALeffectslot() { PropsClean.test_and_set(); }
    ALeffectslot(const ALeffectslot&) = delete;
    ALeffectslot& operator=(const ALeffectslot&) = delete;
    ~ALeffectslot();

    static ALeffectslotArray *CreatePtrArray(size_t count) noexcept;

    DEF_NEWDEL(ALeffectslot)
};

ALenum InitEffectSlot(ALeffectslot *slot);
void UpdateEffectSlotProps(ALeffectslot *slot, ALCcontext *context);
void UpdateAllEffectSlotProps(ALCcontext *context);


EffectStateFactory *NullStateFactory_getFactory(void);
EffectStateFactory *ReverbStateFactory_getFactory(void);
EffectStateFactory *AutowahStateFactory_getFactory(void);
EffectStateFactory *ChorusStateFactory_getFactory(void);
EffectStateFactory *CompressorStateFactory_getFactory(void);
EffectStateFactory *DistortionStateFactory_getFactory(void);
EffectStateFactory *EchoStateFactory_getFactory(void);
EffectStateFactory *EqualizerStateFactory_getFactory(void);
EffectStateFactory *FlangerStateFactory_getFactory(void);
EffectStateFactory *FshifterStateFactory_getFactory(void);
EffectStateFactory *ModulatorStateFactory_getFactory(void);
EffectStateFactory *PshifterStateFactory_getFactory(void);

EffectStateFactory *DedicatedStateFactory_getFactory(void);


ALenum InitializeEffect(ALCcontext *Context, ALeffectslot *EffectSlot, ALeffect *effect);

#endif