gelyk/Source/PluginProcessor.cpp

#include "PluginProcessor.h"
#include "PluginEditor.h"
#include "GitInfo.h"

namespace gelyk
{

namespace
{
juce::AudioProcessorValueTreeState::ParameterLayout createParameterLayout()
{
    juce::AudioProcessorValueTreeState::ParameterLayout layout;

    auto addGain = [&](juce::String id, juce::String name, float def)
    {
        layout.add(std::make_unique<juce::AudioParameterFloat>(
            id, name, juce::NormalisableRange<float>(-24.0f, 24.0f, 0.01f), def));
    };

    auto addQ = [&](juce::String id, juce::String name, float def)
    {
        layout.add(std::make_unique<juce::AudioParameterFloat>(
            id, name, juce::NormalisableRange<float>(0.1f, 6.0f, 0.01f), def));
    };

    auto addFreq = [&](juce::String id, juce::String name, float def)
    {
        auto range = juce::NormalisableRange<float>(20.0f, 20000.0f, 0.5f);
        range.setSkewForCentre(1000.0f);
        layout.add(std::make_unique<juce::AudioParameterFloat>(id, name, range, def));
    };

    addGain("gain0", "Low Shelf Gain", 0.0f);
    addGain("gain1", "Low Gain",      0.0f);
    addGain("gain2", "Low-Mid Gain",  0.0f);
    addGain("gain3", "Mid Gain",      0.0f);
    addGain("gain4", "High-Mid Gain", 0.0f);
    addGain("gain5", "High Gain",     0.0f);
    addGain("gain6", "High Shelf Gain", 0.0f);

    addQ("q0", "Low Shelf Q", 0.71f);
    addQ("q1", "Low Q",       1.0f);
    addQ("q2", "Low-Mid Q",   1.0f);
    addQ("q3", "Mid Q",       1.0f);
    addQ("q4", "High-Mid Q",  1.0f);
    addQ("q5", "High Q",      1.0f);
    addQ("q6", "High Shelf Q", 0.71f);

    addFreq("freq0", "Low Shelf Freq", 60.0f);
    addFreq("freq1", "Low Freq",       160.0f);
    addFreq("freq2", "Low-Mid Freq",   400.0f);
    addFreq("freq3", "Mid Freq",       800.0f);
    addFreq("freq4", "High-Mid Freq",  1600.0f);
    addFreq("freq5", "High Freq",      4000.0f);
    addFreq("freq6", "High Shelf Freq", 10000.0f);

    layout.add(std::make_unique<juce::AudioParameterFloat>(
        "master", "Master", juce::NormalisableRange<float>(-24.0f, 24.0f, 0.01f), 0.0f));

    layout.add(std::make_unique<juce::AudioParameterBool>(
        "analyserEnabled", "Analyser", true));

    return layout;
}

const char* const bandTypes[7] = { "lowShelf", "peak", "peak", "peak", "peak", "peak", "highShelf" };
const float bandFreqs[7] = { 60.0f, 160.0f, 400.0f, 800.0f, 1600.0f, 4000.0f, 10000.0f };
} // namespace

GelykEQAudioProcessor::GelykEQAudioProcessor()
    : AudioProcessor(BusesProperties()
                         .withInput("Input", juce::AudioChannelSet::stereo(), true)
                         .withOutput("Output", juce::AudioChannelSet::stereo(), true)),
      apvts(*this, nullptr, "Parameters", createParameterLayout())
{
    buildVersion = ProjectInfo::versionString;

    gitInfo = juce::String(GELYK_GIT_BRANCH) + " @ " + juce::String(GELYK_GIT_SHA) +
              (juce::String(GELYK_GIT_DIRTY_STR).isNotEmpty() ? " (dirty)" : "") +
              "  |  " + juce::String(GELYK_BUILD_DATE_STR);
}

void GelykEQAudioProcessor::prepareToPlay(double sampleRate, int samplesPerBlock)
{
    currentSampleRate = sampleRate;

    for (int i = 0; i < numBands; ++i)
    {
        bands[i].type = (FilterBand::Type)
            (juce::String(bandTypes[i]) == "lowShelf" ? 0 :
             (juce::String(bandTypes[i]) == "highShelf" ? 2 : 1));
        bands[i].freq = bandFreqs[i];
        bands[i].prepare(sampleRate, samplesPerBlock);
        bands[i].reset();
    }

    analyser.prepare(sampleRate, samplesPerBlock);
    analyser.startBackground();

    rebuildCoefficients();
}

void GelykEQAudioProcessor::releaseResources()
{
    analyser.stopBackground();
}

void GelykEQAudioProcessor::rebuildCoefficients()
{
    for (int i = 0; i < numBands; ++i)
    {
        float gain = apvts.getRawParameterValue("gain" + juce::String(i))->load();
        float q     = apvts.getRawParameterValue("q" + juce::String(i))->load();
        bands[i].gainDb = gain;
        bands[i].q = q;
        bands[i].prepare(currentSampleRate, 512);
    }
}

void GelykEQAudioProcessor::processBlock(juce::AudioBuffer<float>& buffer, juce::MidiBuffer&)
{
    juce::ScopedNoDenormals noDenormals;

    const int numChannels = buffer.getNumChannels();
    const int numSamples = buffer.getNumSamples();

    if (numChannels < 1)
        return;

    // Feed the analyser with the input.
    if (apvts.getRawParameterValue("analyserEnabled")->load() > 0.5f)
    {
        const float* chans[2] = { buffer.getReadPointer(0),
                                  numChannels > 1 ? buffer.getReadPointer(1) : buffer.getReadPointer(0) };
        analyser.push(chans, numChannels > 1 ? 2 : 1, numSamples);
    }

    // Refresh band coefficients (cheap) from smoothed params each block.
    for (int i = 0; i < numBands; ++i)
    {
        float gain = apvts.getRawParameterValue("gain" + juce::String(i))->load();
        float q     = apvts.getRawParameterValue("q" + juce::String(i))->load();
        float freq  = apvts.getRawParameterValue("freq" + juce::String(i))->load();
        if (std::abs(gain - bands[i].gainDb) > 0.001f ||
            std::abs(q - bands[i].q) > 0.001f ||
            std::abs(freq - bands[i].freq) > 0.5f)
        {
            bands[i].gainDb = gain;
            bands[i].q = q;
            bands[i].freq = freq;
            bands[i].prepare(currentSampleRate, numSamples);
        }
    }

    juce::dsp::AudioBlock<float> block(buffer);

    for (int i = 0; i < numBands; ++i)
        bands[i].process(block);

    float master = apvts.getRawParameterValue("master")->load();
    if (std::abs(master) > 0.001f)
        buffer.applyGain(juce::Decibels::decibelsToGain(master));
}

void GelykEQAudioProcessor::getStateInformation(juce::MemoryBlock& destData)
{
    auto state = apvts.copyState();
    std::unique_ptr<juce::XmlElement> xml(state.createXml());
    copyXmlToBinary(*xml, destData);
}

void GelykEQAudioProcessor::setStateInformation(const void* data, int sizeInBytes)
{
    std::unique_ptr<juce::XmlElement> xml(getXmlFromBinary(data, sizeInBytes));
    if (xml != nullptr && xml->hasTagName(apvts.state.getType()))
        apvts.replaceState(juce::ValueTree::fromXml(*xml));
}

juce::AudioProcessorEditor* GelykEQAudioProcessor::createEditor()
{
    return new GelykEQAudioProcessorEditor(*this);
}

} // namespace gelyk

juce::AudioProcessor* JUCE_CALLTYPE createPluginFilter()
{
    return new gelyk::GelykEQAudioProcessor();
}