DaisySP_TeensyDaisySP_Teensy/DaisySP/PhysicalModeling/modalvoice.cpp

#include "modalvoice.h"
#include <algorithm>

using namespace daisysp;

void ModalVoice::Init(float sample_rate)
{
    sample_rate_ = sample_rate;
    aux_         = 0.f;

    excitation_filter_.Init();
    resonator_.Init(0.015f, 24, sample_rate_);
    excitation_filter_.Init();
    dust_.Init();

    SetSustain(false);
    SetFreq(440.f);
    SetAccent(.3f);
    SetStructure(.6f);
    SetBrightness(.8f);
    SetDamping(.6f);
}

void ModalVoice::SetSustain(bool sustain)
{
    sustain_ = sustain;
}

void ModalVoice::Trig()
{
    trig_ = true;
}

void ModalVoice::SetFreq(float freq)
{
    resonator_.SetFreq(freq);
    f0_ = freq / sample_rate_;
    f0_ = fclamp(f0_, 0.f, .25f);
}

void ModalVoice::SetAccent(float accent)
{
    accent_ = fclamp(accent, 0.f, 1.f);
}

void ModalVoice::SetStructure(float structure)
{
    resonator_.SetStructure(structure);
}

void ModalVoice::SetBrightness(float brightness)
{
    brightness_ = fclamp(brightness, 0.f, 1.f);
    density_    = brightness_ * brightness_;
}

void ModalVoice::SetDamping(float damping)
{
    damping_ = fclamp(damping, 0.f, 1.f);
}

float ModalVoice::GetAux()
{
    return aux_;
}

float ModalVoice::Process(bool trigger)
{
    float brightness = brightness_ + 0.25f * accent_ * (1.0f - brightness_);
    float damping    = damping_ + 0.25f * accent_ * (1.0f - damping_);

    const float range  = sustain_ ? 36.0f : 60.0f;
    const float f      = sustain_ ? 4.0f * f0_ : 2.0f * f0_;
    const float cutoff = fmin(
        f
            * powf(2.f,
                   kOneTwelfth
                       * ((brightness * (2.0f - brightness) - 0.5f) * range)),
        0.499f);
    const float q = sustain_ ? 0.7f : 1.5f;

    float temp = 0.f;
    // Synthesize excitation signal.
    if(sustain_)
    {
        const float dust_f = 0.00005f + 0.99995f * density_ * density_;
        dust_.SetDensity(dust_f);
        temp = dust_.Process() * (4.0f - dust_f * 3.0f) * accent_;
    }
    else if(trigger || trig_)
    {
        const float attenuation = 1.0f - damping * 0.5f;
        const float amplitude   = (0.12f + 0.08f * accent_) * attenuation;
        temp = amplitude * powf(2.f, kOneTwelfth * (cutoff * cutoff * 24.0f))
               / cutoff;
        trig_ = false;
    }

    const float one = 1.0f;
    excitation_filter_.Process<ResonatorSvf<1>::LOW_PASS, false>(
        &cutoff, &q, &one, temp, &temp);

    aux_ = temp;

    resonator_.SetBrightness(brightness);
    resonator_.SetDamping(damping);

    return resonator_.Process(temp);
}