horizont/Source/Knob.cpp

#include "Knob.h"

Knob::Knob (const juce::String& title,
            juce::AudioProcessorValueTreeState& apvts,
            const juce::String& paramID,
            float defaultValue,
            std::function<juce::String (float)> formatFn,
            const juce::String& tooltip)
    : format (std::move (formatFn))
{
    nameLabel.setText (title, juce::dontSendNotification);
    nameLabel.setJustificationType (juce::Justification::centred);
    nameLabel.setFont (juce::Font (juce::FontOptions (11.0f, juce::Font::bold)));
    nameLabel.setColour (juce::Label::textColourId, juce::Colour (0xFFB8CCCC));
    nameLabel.setInterceptsMouseClicks (false, false);
    addAndMakeVisible (nameLabel);

    valueLabel.setJustificationType (juce::Justification::centred);
    valueLabel.setFont (juce::Font (juce::FontOptions (11.0f, juce::Font::bold)));
    valueLabel.setColour (juce::Label::textColourId, juce::Colour (0xFF3CE0C8));
    valueLabel.setInterceptsMouseClicks (false, false);
    addAndMakeVisible (valueLabel);

    slider.setSliderStyle (juce::Slider::RotaryHorizontalVerticalDrag);
    slider.setTextBoxStyle (juce::Slider::NoTextBox, true, 0, 0);
    slider.setDoubleClickReturnValue (true, defaultValue);
    slider.setWantsKeyboardFocus (true);
    slider.setScrollWheelEnabled (true);
    slider.setTooltip (tooltip);
    slider.onValueChange = [this] { updateValueLabel(); };
    addAndMakeVisible (slider);

    attachment = std::make_unique<juce::AudioProcessorValueTreeState::SliderAttachment> (apvts, paramID, slider);

    updateValueLabel();
}

void Knob::setScaleFactor (float scale)
{
    scaleFactor = scale;
    resized();
}

void Knob::updateValueLabel()
{
    valueLabel.setText (format (slider.getValue()), juce::dontSendNotification);
}

void Knob::paint (juce::Graphics& g)
{
    auto b = slider.getBounds().toFloat();
    auto shadow = b.translated (0.0f, b.getHeight() * 0.05f).expanded (b.getWidth() * 0.05f);
    auto shadowCentre = shadow.getCentre().withY (shadow.getCentre().getY() + b.getHeight() * 0.4f);
    auto grad = juce::ColourGradient (juce::Colour (0x60000000), shadowCentre,
                                      juce::Colour (0x00000000), shadowCentre.translated (shadow.getWidth() * 0.7f, 0.0f),
                                      true);
    grad.addColour (0.55f, juce::Colour (0x20000000));
    g.setGradientFill (grad);
    g.fillEllipse (shadow);
}

void Knob::resized()
{
    auto bounds = getLocalBounds();
    const float s = scaleFactor;

    const int nameH = juce::roundToInt (18.0f * s);
    const int valueH = juce::roundToInt (16.0f * s);
    const int maxKnobSize = juce::roundToInt (84.0f * s);

    auto nameArea = bounds.removeFromTop (nameH);
    auto valueArea = bounds.removeFromBottom (valueH);
    nameLabel.setBounds (nameArea);
    valueLabel.setBounds (valueArea);

    nameLabel.setFont (juce::Font (juce::FontOptions (juce::roundToInt (11.0f * s), juce::Font::bold)));
    valueLabel.setFont (juce::Font (juce::FontOptions (juce::roundToInt (11.0f * s), juce::Font::bold)));

    const int knobSize = jmin (bounds.getWidth(), bounds.getHeight(), maxKnobSize);
    slider.setBounds (bounds.getCentreX() - knobSize / 2, bounds.getCentreY() - knobSize / 2, knobSize, knobSize);
}