36 lines
1.1 KiB
C++
36 lines
1.1 KiB
C++
#include "synthisizer.h"
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#include <cmath>
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#include "midicontainers.h"
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constexpr double pi = std::acos(-1);
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void Synthisizer::writeSamples(frame_t *begin, frame_t *end)
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{
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const auto frequency = m_frequency;
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if (frequency)
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std::transform(begin, end, begin, [&](frame_t frame){
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std::transform(std::cbegin(frame), std::cend(frame), std::begin(frame),
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[value=std::sin(m_phase)](const sample_t &sample) { return sample + value; });
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m_phase += pi*2./frameRate*m_actualFrequency;
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if (m_phase >= pi*2.)
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m_phase -= pi*2.;
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return frame;
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});
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m_actualFrequency = float(m_actualFrequency+m_frequency)/2.f;
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}
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void Synthisizer::messageReceived(const midi::MidiMessage &message)
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{
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if (message.cmd == midi::Command::NoteOn)
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m_frequency = 440.*std::pow(std::pow(2., 1./12.), message.note-48);
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else if (message.cmd == midi::Command::NoteOff)
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{
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if (m_frequency == int16_t(440.*std::pow(std::pow(2., 1./12.), message.note-48)))
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m_frequency = 0;
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}
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}
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