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#include "../utility/dsp.h"
#include "variablesawosc.h"
#include <math.h>
using namespace daisysp;
void VariableSawOscillator::Init(float sample_rate)
{
sample_rate_ = sample_rate;
phase_ = 0.0f;
next_sample_ = 0.0f;
previous_pw_ = 0.5f;
high_ = false;
SetFreq(220.f);
SetPW(0.f);
SetWaveshape(1.f);
}
float VariableSawOscillator::Process()
{
float next_sample = next_sample_;
float this_sample = next_sample;
next_sample = 0.0f;
const float triangle_amount = waveshape_;
const float notch_amount = 1.0f - waveshape_;
const float slope_up = 1.0f / (pw_);
const float slope_down = 1.0f / (1.0f - pw_);
phase_ += frequency_;
if(!high_ && phase_ >= pw_)
{
const float triangle_step
= (slope_up + slope_down) * frequency_ * triangle_amount;
const float notch
= (kVariableSawNotchDepth + 1.0f - pw_) * notch_amount;
const float t = (phase_ - pw_) / (previous_pw_ - pw_ + frequency_);
this_sample += notch * ThisBlepSample(t);
next_sample += notch * NextBlepSample(t);
this_sample -= triangle_step * ThisIntegratedBlepSample(t);
next_sample -= triangle_step * NextIntegratedBlepSample(t);
high_ = true;
}
else if(phase_ >= 1.0f)
{
phase_ -= 1.0f;
const float triangle_step
= (slope_up + slope_down) * frequency_ * triangle_amount;
const float notch = (kVariableSawNotchDepth + 1.0f) * notch_amount;
const float t = phase_ / frequency_;
this_sample -= notch * ThisBlepSample(t);
next_sample -= notch * NextBlepSample(t);
this_sample += triangle_step * ThisIntegratedBlepSample(t);
next_sample += triangle_step * NextIntegratedBlepSample(t);
high_ = false;
}
next_sample += ComputeNaiveSample(
phase_, pw_, slope_up, slope_down, triangle_amount, notch_amount);
previous_pw_ = pw_;
next_sample_ = next_sample;
return (2.0f * this_sample - 1.0f) / (1.0f + kVariableSawNotchDepth);
}
void VariableSawOscillator::SetFreq(float frequency)
{
frequency = frequency / sample_rate_;
frequency = frequency >= .25f ? .25f : frequency;
pw_ = frequency >= .25f ? .5f : pw_;
frequency_ = frequency;
}
void VariableSawOscillator::SetPW(float pw)
{
if(frequency_ >= .25f)
{
pw_ = .5f;
}
else
{
pw_ = fclamp(pw, frequency_ * 2.0f, 1.0f - 2.0f * frequency_);
}
}
void VariableSawOscillator::SetWaveshape(float waveshape)
{
waveshape_ = waveshape;
}
float VariableSawOscillator::ComputeNaiveSample(float phase,
float pw,
float slope_up,
float slope_down,
float triangle_amount,
float notch_amount)
{
float notch_saw = phase < pw ? phase : 1.0f + kVariableSawNotchDepth;
float triangle
= phase < pw ? phase * slope_up : 1.0f - (phase - pw) * slope_down;
return notch_saw * notch_amount + triangle * triangle_amount;
}